Seasonal weather effects on the common eider, a subarctic capital breeder, in Iceland over 55 years - Jonsson, Jon Einar; Gardarsson, Arnthor; Gill, Jennifer A.; Petersen, Aevar; Gunnarsson, Tomas Gretar (Climate Research, 2009)
Changes in bird populations and their phenology (i.e. timing of nesting and migration) are increasingly linked to global climatic changes, particularly at temperate and Arctic latitudes. These patterns arise from local- and regional-scale effects of weather on demography but long-term time-series data necessary to explore these relationships are rarely available. Colonies of the common eider Somateria mollissima are often monitored annually for nest-down harvesting. We use long-term data from 2 nesting colonies in northwest Iceland (Bildsey, Breidafjordur: 29 yr and Laekur, Dyrafjorour: 55 yr) to examine the effects of weather conditions in each season on breeding numbers, arrival dates and clutch sizes. Numbers of nests in Bildsey increased following warm, wet winters and first nests were produced later following windy and wet winters at Laekur. In spring, windy conditions tended to be followed by earlier female arrivals at Bildsey. Warm, wet springs were positively correlated with larger clutch sizes at Laekur, and clutch sizes at Laekur decreased following especially wet and warm autumns. The overall population trends vary among sites and are likely to be influenced by both climatic and management conditions. These findings indicate that the effects of global climatic changes will depend on the details of changes in local weather conditions within each season. The strong effects on nesting dates and clutch sizes suggest that accumulation of body reserves, which sustain females during incubation and into brood rearing, is a key mechanism that could determine how altered distribution and frequencies of depressions within each season will affect future numbers of this species.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Common Eider; Somateria mollissima; Productivity

Relationships between Long-Term Demography and Weather in a Sub-Arctic Population of Common Eider - Jonsson, J. E.; Gardarsson, A.; Gill, J. A.; Petursdottir, U. K.; Petersen, A.; Gunnarsson, T. G. (Plos One, 2013)
Times Cited: 0 Jonsson, Jon Einar Gardarsson, Arnthor Gill, Jennifer A. Petursdottir, Una Kristin Petersen, Aevar Gunnarsson, Tomas Gretar 0
Keywords: Breeding Season; Abundance, Distribution, and Trends; Somateria mollissima; Productivity; Population Dynamics; Common eider

The early birds and the rest: do first nesters represent the entire colony? - Jonsson, J. E.; Ludviksson, S. J.; Kaller, M. D. (POLAR BIOLOGY, 2017)
Climate change studies have detected earlier spring arrival of breeding birds. However, first nest dates (date first nests were found), which commonly provide the metric for earlier arrival, can be biased by population size or sampling effort. Our aims were to determine if: 1) first nest dates and median nest date (date when at least 50 % of all females have nested) were equivalent predictors for the spring arrival and 2) first nest date or median nest date were related to nest numbers. We recorded first and median nest dates and nest numbers at the common eider (Somateria mollissima) colony at Rif, Iceland, during 1992-2013. First nest date was advanced by 11 days during the study, but median nest date was advanced by only 4 days. First nest date and median nest date were correlated, but this relationship was only a small improvement over the null model (Nagelkerke R (2) = 30 %). We found a relationship with nest count for both first and median nest dates once the analysis had accounted for inter-annual variability. First nest date may not represent the colony as a whole but rather the physically fittest or the most determined individuals, which may be more prone to nest early than the general population. Nesting birds must decide how much to advance breeding based on nest numbers and other non-temporal cues which necessitate earlier breeding. We argue that nest numbers affect the birds in a biological sense and that the advancement was not explained solely by increased nest numbers.
Times Cited in Web of Science Core Collection: 6 Total Times Cited: 6 Cited Reference Count: 64
Keywords: Climate change; EIDERS SOMATERIA-MOLLISSIMA; CLIMATE-CHANGE; CLUTCH-SIZE; COMMON EIDER; LAYING DATE; REPRODUCTIVE CONSEQUENCES; Arrival date; CAPITAL BREEDER; Eider; First nest date; Nest numbers; NESTING SUCCESS; SITE SELECTION; STRESS RESPONSIVENESS

A choice between two adjacent islands: is switching nest sites related to weather or nest density in the Common Eider (Somateria mollissima)? - Jonsson, J. E.; Luoviksson, S. J. (Ornis Fennica, 2013)
Times Cited: 1 Jonsson, Jon Einar Luoviksson, Smari J. 1
Keywords: Behavior; Breeding Season; Somateria mollissima; Common eider; habitat

Population overview of eider ducks - Jonsson, Jon Einar; Petersen, Aevar; Garoarsson, Arnpor; Gunnarsson, Tomas G. (Natturufraedingurinn, 2009)
Seabird populations are much discussed because of possible impacts of global climate change. Eider ducks (Somatereae) are a monophyletic group comprised of four species of specialized ducks that all live along the Arctic coastline. Most populations are listed as of special concern with a few exceptions, notably the Common Eider (Somateria mollissima) in Iceland. The other species are King Eider (S. spectabilis), Spectacled Eider (S. fischeri) and Steller's Eider (Polysticta stelleri). Many populations are hunted, especially those of Common Eider and King Eider, where over-harvest has been implicated as the cause of population declines. All eider duck species face disturbances from human activities, i.e. from oil spills, contaminants, and drowning in gill-nets. Climate change might increase the occurrences of inclement weather at the highest latitudes, which is likely to negatively impact eiders. However, reduced sea ice near breeding grounds could be beneficial on a local scale. Eider duckling survival is relatively low during first days of life because they are sensitive to food shortage, weather and predators during that time. However, there are few data that indicate that production limits eider duck populations because adult survival is the key factor for population stability among long-living species. Future research is critical as future prospects of eider ducks greatly depend on impending changes and human activities throughout their range.
Keywords: Conservation; Somateria fischeri; Spectacled Eider; Common Eider; Somateria mollissima; King Eider; Somateria spectabilis; Polysticta stelleri; Steller's eider

July-August migration of the common scoter, M. nigra - Jorgensen, Jorgen (Dansk Ornithol Foren Tidsskr, 1941)
For 16 years in s. Slesvig the author has seen migrations of common scoters, sometimes in huge flocks, in July and August, moving from the Baltic to North Sea waters, to the coast of England, where they remain to molt the flight feathers. Observations suggest that earlier migrants are young birds, later ones non-breeding adults or those that failed in nesting efforts. Literature on the subject is reviewed. || ABSTRACT AUTHORS: O. J. Murie
Keywords: Nonbreeding Seasons; Molt; Migration; Black Scoter; Melanitta nigra

Organochlorine Compounds and Their Metabolites in Seven Icelandic Seabird Species - a Comparative Study - Jorundsdottir, Hronn; Lofstrand, Karin; Svavarsson, Jorundur; Bignert, Anders; Bergman, Ake (Environmental Science & Technology, 2010)
The present study is designed to assess the occurrence of a few organochlorine contaminants and their metabolites in eggs of different marine bird species in Iceland, a country located in the sub-Arctic of the North-Western Atlantic. Previous investigations from e.g. Sweden and The Netherlands have shown some obvious differences in contaminant concentrations, including e.g. hydroxylated polychlorinated biphenyl metabolites (OH-PCBs) in guillemot (Uria aalge) and other bird species. Eggs from seven marine bird species, Arctic tern (Sterna paradisaea), common eider (Somateria mollissima), guillemot, fulmar (Fulmarus glacialis), great black-backed gull (Larus marinus), lesser black-backed gull (Larus fuscus), and great skua (Stercorarius skua), that all breed in Iceland, were collected and analyzed for several persistent organic compounds and their metabolites. The contaminant levels varied between the species investigated. The highest concentrations were found in eggs from the great skua (18 and 23 mu g/g I.w. of CB-153 and 4,4'-DDE, respectively). The concentration difference was generally 2 orders of magnitude higher in great skua for all organochlorine compounds analyzed with the exception of HCB. HCB did not vary as much between the seven species (ranging from 34 to 710 ng/g I.w). OH-PCB and MeSO2-PCB metabolites congener concentrations and patterns showed differences in metabolic capacity between bird species. Guillemot and great skua seem to distinguish themselves most from other species i.e. with the absence of 4-OH-CB187 and low relative levels of 4-OH-CB146 in guillemot and the low abundance of OH-PCBs in great skua.
Keywords: Breeding Season; Common Eider; Contaminants; Somateria mollissima

Polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD) in seven different marine bird species from Iceland - Jorundsdottir, H.; Lofstrand, K.; Svavarsson, J.; Bignert, A.; Bergman, A. (Chemosphere, 2013)
Times Cited: 0 Jorundsdottir, Hronn Lofstrand, Karin Svavarsson, Jorundur Bignert, Anders Bergman, Ake 0
Keywords: Contaminants; Somateria mollissima; Common eider

The nesting of Steller's Eider in Norway - Jourdain, F. C. R. (Ibis, 1926)
Comments on a letter by H. W. Robinson. || ABSTRACT AUTHORS: W. W. Bowen
Keywords: Breeding Season; Polysticta stelleri; Steller's eider

Community associations of birds with amphibians and fish in wetlands created for biodiversity - Kacergyte, I.; Knape, J.; Zmihorski, M.; Arlt, D.; Part, T. (BIOLOGICAL CONSERVATION, 2023)
Conservation initiatives to support declining water-related biodiversity through wetland creation have increased during the last decades. Multiple studies have evaluated the suitability of created wetlands for birds and amphibians, but only a few have considered the species associations that might also affect the outcome. Using joint species distribution models, we explored species associations of birds, amphibians and fish in 52 created biodiversity wetlands in Sweden. As most of these wetlands were primarily created for increasing bird diversity, we asked whether the occurrence of fish and amphibians relates to bird species richness, pair abundance and chick abundance (as a measure of reproductive success) and whether conservation conflicts or synergies between birds, amphibians and fish can be observed. In general, we found positive bird-amphibian association patterns and negative bird-fish association patterns, although the uncertainties were high for these estimates. In line with previous research, the generally negative bird-fish co-variance indicates potential conservation conflicts between wetland creation for birds and fish, where fish might be introduced for recreational fishing or other ecosystem services. Therefore, our results suggest that it can be hard to benefit bird and fish communities with the same wetland, and separate wetland creation with different goals may be needed. The generally positive birdamphibian species-species associations and the lack of previous studies revealing conflicts indicate synergies between wetland creation for birds and amphibians. However, research needs to further consolidate such synergies, including amphibian reproductive output from bird-rich wetlands.
Times Cited in Web of Science Core Collection: 0 Total Times Cited: 0 Cited Reference Count: 60
Keywords: BUCEPHALA-CLANGULA; Biodiversity assessment; COMPETITION; CONCORDANCE; Constructed pond; CONSTRUCTION; ECOSYSTEM SERVICES; eDNA; Freshwater vertebrates; HMSC; LAKE; RESTORATION; Species interactions; SPECIES RICHNESS; TRENDS; WATERBIRDS

Effects of human disturbance on broods of Red-breasted Mergansers Mergus serrator - Kahlert, Johnny (Wildfowl, 1994)
The effects of human disturbance on broods of Red-breasted Mergansers were studied at three Danish localities. Fast-moving boots (fishermen, windsurfers, and motor boats) were considered to have the greatest impact on Merganser broods as frequency of encounters and rote of disturbance were highest. The presence of fast-moving boots also caused the most significant modifications to time budgets. However, Merganser broods are considered quite resilient to human disturbance as they quickly resumed their former activities after disturbance, and at moderate disturbance levels, interruptions to comfort behaviour were compensated for within 1 1/2 hours. However, on one locality with high disturbance levels and frequent high-speed boating, the survival of ducklings was reduced.
Keywords: Conservation; Behavior; Breeding Season; Mergus serrator; Red-breasted merganser

Winter segregation and timing of pair formation in Red-breasted Merganser Mergus serrator - Kahlert, Johnny; Coupe, Malcolm; Cooke, Fred (Wildfowl, 1999)
During the late winter and spring of 1997, sex-ratios and pairing chronology of Red-breasted Mergansers were studied in the Fraser River Estuary, south west Canada. Until late March at one site, English Bay, there was a strong male-bias, whereas a female bias was evident at the nearby Boundary Bay. This pattern was interpreted as sexual winter segregation. At the male-biased site, antagonistic and kleptoparasitic behaviour initiated by males towards females could not account for the winter segregation. In late March and April, the sex ratios at the two study sites converged to similar values. This trait coincided with an increase in the number of courtship displays and percentage of paired birds. Although the majority of mergansers exhibited this pairing chronology, pairs were observed as early as mid-February, suggesting a gradient in the timing of pair formation. Pairs tended to segregate from flocks. If pairs are able to segregate throughout the winter early pairing may be beneficial as food resources could be monopolised and interference with conspecifics avoided. However, the frequency of interactions with conspecifics tends to be unpredictable, since local population size fluctuated considerably.
Keywords: Behavior; Nonbreeding Seasons; Mergus serrator; Red-breasted merganser

Distribution and behaviour of Common Scoter Melanitta nigra relative to prey resources and environmental parameters - Kaiser, M. J.; Galanidi, M.; Showler, D. A.; Elliott, A. J.; Caldow, R. W. G.; Rees, E. I. S.; Stillman, R. A.; Sutherland, W. J. (Ibis, 2006)
Offshore wind farms are proposed around the coast of the UK and elsewhere in Europe. These sites tend to be located in shallow coastal waters that often coincide with areas used by over-wintering Common Scoter Melanitta nigra. A large-scale study was undertaken to ascertain the relationship of the spatial distribution of Common Scoter in Liverpool Bay with prey abundance and environmental and anthropogenic variables that may affect foraging efficiency. The highest numbers of Common Scoter coincided with sites that had a high abundance and biomass of bivalve prey species. There was strong evidence that the maximum observed biomass of bivalves occurred at a mean depth of c. 14 m off the Lancashire coast and at c. 8 m off the north Wales coast. This coincided well with the distribution of Common Scoter at Shell Flat, but less well with the distribution of birds off North Wales. Common Scoters were observed in lowest numbers or were absent from areas in which anthropogenic disturbance ( shipping activity) was relatively intense, even when these areas held a high prey biomass. Commercial fishing activities did not appear to contribute to this disturbance.
Keywords: Abundance, Distribution, and Trends; Nonbreeding Seasons; Habitat; Black Scoter; Melanitta nigra

Do flocks of great cormorants and goosanders avoid spatial overlap in foraging habitat during the non-breeding season? - Kajtoch, L.; Leso, P.; Matysek, M.; Kata, M.; Gacek, S.; Zontek, C.; Bisztyga, A.; Gwiazda, R. (AQUATIC ECOLOGY, 2017)
Species distribution, ecology, and behaviour are shaped, amongst other things, by interspecific, antagonistic interactions, and this phenomenon is particularly noticeable among predators. We studied the spatial co-distribution of two top piscivorous bird species foraging on inland waters outside breeding season. We considered the hypothesis that goosanders, Mergus merganser, and great cormorants, Phalacrocorax carbo, avoid foraging in close proximity to each other. Data collected on five river-reservoir systems in the Western Carpathians (Poland and Slovakia) during two periods (2014-2015 and 2015-2016) showed that goosander numbers reduced significantly and their foraging areas changed when large flocks of cormorants arrived and began foraging. We also found that inter-flock distances were greatest between flocks of goosanders and cormorants, suggesting that the former species avoided the waters occupied by the latter. Distribution of flocks of both species was additionally determined by the location of foraging place in river-reservoir system, weather, and presence of other piscivorous birds (e.g. grebes) and raptors (e.g. eagles). Together with the results of research in adjacent Bohemia, this study suggests that competition between cormorants and goosanders may arise when bodies of water suitable for piscivorous foraging are scattered and limited in number, as in the mountainous areas of Central Europe.
Times Cited in Web of Science Core Collection: 1 Total Times Cited: 3 Cited Reference Count: 53
Keywords: Mergus merganser; PATTERNS; FOOD; PREY; WATERBIRDS; INTERFERENCE COMPETITION; Interspecific competition; MERGANSER MERGUS-SERRATOR; Phalacrocorax carbo; PHALACROCORAX-CARBO-SINENSIS; Piscivores; PISCIVOROUS BIRDS; PREFERENCES; RED; Spatial ecology

Settlement of the Raba River basin by the Goosander Mergus merganser - Kajtoch, Lukasz; Piestrzynska-Kajtoch, Agata (Notatki Ornitolgiczne, 2005)
A study of the distribution and abundance of a new population of the Goosander was conducted in the Raba River basin (south-eastern Poland) in 2000-2005. In particular years, the number of pairs ranged between 4 and 16. The decrease in the number of breeding pairs recorded for 2002-2004 was caused by cutting of forests and regulation of the river bed. The Goosander populated also the Dobczycki Reservoir and the Stradomka, Tarnawka and Krzyworzeka River valleys in the Wisnicki Foothill, forming the first population in the Polish Carpathian Mts. In 2005 the total abundance of this species was estimated at 20-24 pairs. it probably breeds in burrows and in beech forests, and is likely to spread into other river valleys of the Carpathian Foothills in the future.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Common merganser; Mergus merganser

Are Goosanders good indicators of Carpathian's submontane river valleys naturalness and biodiversity? - Kajtoch, L.; Zmihorski, M. (Acta Biologica Cracoviensia Series Botanica, 2013)
Times Cited: 0 Kajtoch, Lukasz Zmihorski, Michal Kajtoch, Lukasz/B-4236-2012 Kajtoch, Lukasz/0000-0001-7345-9400 0 1
Keywords: Conservation; Breeding Season; Common merganser; Mergus merganser

The Goosander as potential indicator of naturalness and biodiversity in submontane river valleys of northern Carpathians - Kajtoch, L.; Zmihorski, M.; Piestrzynska-Kajtoch, A. (Ecological Indicators, 2014)
Riparian habitats are biodiversity hotspots, however, despite their protection (e.g. in Natura 2000 sites) they are drastically transformed, particularly in more developed countries. The least inventoried, monitored and protected are submontane drainages composed of lowland and mountain habitats and species. Effective evaluation and monitoring of riparian habitat quality and species richness in submontane valleys is difficult and time consuming, but could be overcome by using indicator species. In this work, we verify if Goosander Mergus merganser could be considered as indicators of submontane valleys' naturalness and biodiversity. Data about Goosander occurrence in the Raba drainage (Polish Carpathians) were compared with several environmental variables and information about species richness of selected riparian animals. Goosander distribution and abundance depended on "naturalness" variables (high share of alluvia and scarps in river channels and forests on river banks), but association with hydrogeomorphology and the vicinity of humans was not found. Goosander abundance was found to be significantly correlated with bird species richness (both forest- and river-dwellers) and the presence of aquatic mammals (beavers and otters), but not with a richness of fish. Moreover, Goosander allows a high prediction accuracy to be achieved for the presence of aquatic animals (otters, beavers, woodpeckers and river-dwelling birds), among others, species annexed in EU directives. The correlation of Goosander abundance with the richness of riparian vertebrates, as well as with natural riparian habitats makes this bird a good candidate for an umbrella and flagship species. Moreover, using Goosanders as indicators would be a valuable method for preliminary valorization and further monitoring of habitats and species in Natura 2000 sites of Polish Carpathians. The utility of this species as bioindicator in other parts of the Carpathians should be verified after saturation of available areas by its populations. (C) 2014 Elsevier Ltd. All rights reserved.
Kajtoch, Lukasz Zmihorski, Michal Piestrzynska-Kajtoch, Agata
Keywords: Conservation; Breeding Season; Mergus merganser; Habitat; Abundance, Distribution, & Trends; Common Merganser

Feeding behaviour and diet of goosanders (Mergus merganser) in relation to salmonid seaward migration - Kalas, John Atle; Heggberget, Tor G.; Bjorn, Pal Arne; Reitan, Ole (Aquatic Living Resources, 1993)
Foraging activities of goosanders (Anatidae, Mergus merganser) were studied in relation to seaward migration of smolt in the River Halselva in northern Norway, 1987-1989. Birds aggregated in the estuary in June, during mass migration of smolts. When present in the estuary males and females spent 28.7 and 35.6% of their time feeding. Only 15% of dives resulted in birds' bringing prey to the surface and about 25% of prey found in goosander stomachs were salmonoids. For hatchery-reared smolts released in the estuary, average length taken did not differ from that available; for wild smolts of Arctic char, however, smaller fishes than those available were taken. For 1989, we estimate that goosanders took 1% of the hatchery-reared smolts released in the estuary, and 2% of the wild smolts when smolts passed the estuary during seaward migration. As it is likely that less fit smolts (e. g. sick, injured, small) are most prone to predation we argue that such a level of predation on migrating smolts from goosanders has only a minor impact on salmonid production. Suggestions to reduce predation are discussed.
Keywords: Conservation; Breeding Season; Trophic Interactions; Common merganser; Mergus merganser

Numbers and distribution of wintering divers, grebes and seaducks in the Moray Firth, Scotland, 1998/99-2003/04 - Kalejta-Summers, Bozena; Butterfield, David (Wildfowl, 2006)
Numbers of divers, grebes and seaducks were counted in the Moray Firth during six consecutive winters between 1998/99 and 2003/04, and compared with earlier surveys. Common Scoter Melanitta nigra, Long-tailed Duck Clangula hyentails and Eider Somateria mollissima were the most abundant species, accounting for over 70% of all birds counted. When maximum winter numbers during the study period were compared with published data for earlier years, declines in numbers were apparent for Goosander Mergus merganser, Long-tailed Duck and Eider since the early 1980s, and for Red-breasted Merganser M. serrator since the late 1980s. Counts of Goldeneye Bucephala clangula have increased since the early 1980s and those of Scaup, Common Scoter and Velvet Scoter M. fusca since the late 1980s. There were considerable changes in the distribution of several species within the Moray Firth, probably in response to changes in the food supply attributed to improvements to sewage and distillery discharges and to associated declines in fish and Blue Mussel Mytilus edulis populations. The Moray Firth supports internationally important numbers of two species (Great Northern Diver Gavia immer and Slavonian Grebe Podiceps auritus) and is nationally important for 10 other diver, grebe and seaduck species. The area supports the largest numbers of wintering Long-tailed Duck and the second largest numbers of Great Northern Diver, Red-throated Diver G. stellata, Slavonian Grebe, Common Scoter,Velvet Scoter and Goldeneye in Britain.
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons

Fluoride concentrations in the pineal gland, brain and bone of goosander (Mergus merganser) and its prey in Odra River estuary in Poland - Kalisinska, E.; Bosiacka-Baranowska, I.; Lanocha, N.; Kosik-Bogacka, D.; Krolaczyk, K.; Wilk, A.; Kavetska, K.; Budis, H.; Gutowska, I.; Chlubek, D. (Environmental Geochemistry and Health, 2014)
The aim of the study was to investigate fluoride concentrations in bone, brain and pineal gland of goosander Mergus merganser wintering in the Odra estuary ( Poland) as well as in fish originating from its digestive tract. The fluoride concentrations were determined with potentiometric method. Medians of concentrations in goosander had the highest and the lowest values in pineal gland and brain (>760 and <190 mg/kg, respectively). Fluoride concentration in the pineal gland was significantly greater than in the bone and the brain of the duck. In fish, the fluoride concentration ranged from 37 to 640 mg/kg and significant correlation was revealed between the fluoride concentration and fish weight and length. Based on own results and data of other authors, a daily fluoride intake by the goosander in the Odra estuary was estimated at 15 mg. So high fluoride concentrations like in the duck have not been found in mammal brains.
Kalisinska, Elzbieta Bosiacka-Baranowska, Irena Lanocha, Natalia Kosik-Bogacka, Danuta Krolaczyk, Katarzyna Wilk, Aleksandra Kavetska, Katarzyna Budis, Halina Gutowska, Izabela Chlubek, Dariusz
Keywords: Contaminants; Mergus merganser; Common Merganser

Body condition and mercury concentration in apparently healthy goosander (Mergus merganser) wintering in the Odra estuary, Poland - Kalisinska, Elzbieta; Budis, Halina; Podlasinska, Joanna; Lanocha, Natalia; Kavetska, Katarzyna M. (Ecotoxicology, 2010)
Goosanders (Mergus merganser, ad, adult n = 42: M, males 33 and F, females 9; im, immature n = 17: M 8, F 9) were collected in 2005 at wintering site in the River Odra estuary (Poland). The body size (BM, body mass; BL, body length; KL, keel length), weights of organs (LM, liver; KM, kidneys; EM, encephalon), and two condition-related indices (BM/BL and BM/KL) were determined. Based on BM/BL and BM/KL indices, the birds were divided into 3 condition groups: A (very good), B (good), and C (moderate). Total mercury (Hg) concentrations (mg kg(-1) dry weight) were determined in liver, kidney, brain, breast muscle, and bone of 17 birds (ad, n = 8: 8 M, 1 F; im, n = 9: 6 M, 3 F). The highest Hg concentrations (in n = 17) were recorded in liver and kidney (14.7 and 9.9 mg kg(-1), respectively); the concentrations found in muscle and brain were lower (2.3 and 1.3 mg kg(-1), respectively), the lowest concentrations being typical of bone (0.08 mg kg(-1)). Mercury concentrations in the same organs of immature and adult goosanders, as well as males and females, did not differ significantly. On the other hand, distinct differences in Hg concentrations in the organs studied (except for the liver) were observed between individuals assigned to Group A (n = 11) and C (n = 6). Mercury levels were higher in the birds characterised by very good condition, which was most probably related to those birds being more efficient hunters, consuming higher amounts of Hg-containing fish. Significant and negative correlations between the muscle Hg concentration and the two condition-related indices (r > -0.70) were recorded in Group A only: the higher the concentration, the lower the BM/LM and BM/KL values.
Keywords: Nonbreeding Seasons; Contaminants; Physiology; Common merganser; Mergus merganser

HEPATIC AND NEPHRIC MERCURY AND SELENIUM CONCENTRATIONS IN COMMON MERGANSERS, MERGUS MERGANSER, FROM BALTIC REGION, EUROPE - Kalisinska, E.; Gorecki, J.; Okonska, A.; Pilarczyk, B.; Tomza-Marciniak, A.; Budis, H.; Lanocha, N.; Kosik-Bogacka, D. I.; Kavetska, K. M.; Macherzynski, M.; Golas, J. (Environmental Toxicology and Chemistry, 2014)
The subject of the present study was the piscivorous common mergansers (Mergus merganser). The total mercury (THg), methylmercury (MeHg), selenium (Se) inorganic mercury (InHg; THg - MeHg), percentage of THg that is MeHg (%MeHg), molar ratios (THg:Se, MeHg:Se, InHg:Se), and their mutual relations in livers and kidneys were determined in ducks from an Se-deficient area in Poland. The authors verified a hypothesis that, as a result of living in an Se-deficient region, mergansers from Poland should have higher THg:Se ratios than other waterbirds with similar THg tissue levels. Although a comparison of healthy mergansers from Poland and Canada showed similar THg tissue contents, the group in the present study had a few times lower Se levels and higher THg:Se ratios (overall means >1.7 in both livers and kidneys in all studied individuals) than the Canadian group and other European and North American waterbirds. The authors found significant correlations between various relations, including MeHg-THg, InHg-THg, Se-THg, %MeHg-THg, InHg/%THg-THg, %MeHg/THg-InHg, %InHg/THg-InHg, MeHg:Se-THg:Se, InHg:Se-THg:Se, InHg:Se-MeHg:Se in liver and InHg-THg, Se-THg, Se-InHg, %MeHg-THg, %MeHg-InHg, %InHg/THg-InHg, THg:Se-THg, InHg:Se-THg, MeHg:Se-MeHg, THg:Se-InHg, InHg:Se-InHg, and InHg:Se-THg:Se in kidney. It is likely that the main factor responsible for the high value of THG:Se ratio (>1) in mergansers from Poland is Se deficiency in central and northern Europe. Therefore, this element is unlikely to participate in the detoxification of Hg in these birds. (c) 2013 SETAC
Kalisinska, Elzbieta Gorecki, Jerzy Okonska, Anna Pilarczyk, Bogumila Tomza-Marciniak, Agnieszka Budis, Halina Lanocha, Natalia Kosik-Bogacka, Danuta I. Kavetska, Katarzyna M. Macherzynski, Mariusz Golas, Janusz
Keywords: Contaminants; Mergus merganser; Common Merganser

Mercury and selenium in the muscle of piscivorous common mergansers (Mergus merganser) from a selenium-deficient European country - Kalisinska, E.; Gorecki, J.; Okonska, A.; Pilarczyk, B.; Tomza-Marciniak, A.; Budis, H.; Lanocha, N.; Kosik-Bogacka, D. I.; Kavetska, K. M.; Macherzynski, M.; Golas, J. M. (Ecotoxicology and Environmental Safety, 2014)
Although the relationship between mercury (Hg) and selenium (Se) has been studied in wild birds in areas with sufficient or excessive Se levels, little is known about this relationship in areas where the supply of Se is limited. As Hg detoxification is based on the production of biologically inactive Hg-Se complexes, the aim of this study was to investigate the relationships between the concentrations of total mercury (THg), methylmercury (MeHg), inorganic mercury (InHg=THg-MeHg), percent MeHg of THg, Se and molar ratios (THg:Se, MeHg:Se, InHg:Se) in the breast muscle (n=16) of the piscivorous common mergansers (Mergus merganser) from a Se-deficient and moderately Hg-polluted area in Poland. Mergansers were divided into two groups differing in condition (A very good condition; C moderate condition). Concentrations of THg, MeHg and Se were determined by atomic absorption spectrometry, modified gas chromatography atomic fluorescence spectroscopy, and spectrofluorometric methods, respectively. In all studied mergansers, mean concentrations of THg, MeHg, InHg, and Se in muscle were 2.63, 1.92, 0.46, and 0.54 mu g g(-1) dw, respectively. THg and MeHg concentrations in the muscle of group A mergansers were greater than in group C. The ratio of THg:Se was higher in group A than in group C (2.32 vs 1.36; p < 0.01), as well as the molar ratio of MeHg:Se (A vs C: 1.98 vs 1.03; p < 0.05). Comparisons between mergansers from Poland and Canada showed similar THg and percent MeHg in the muscle, but mergansers from Poland had several times lower Se levels and higher THg:Se ratios ( > 2.0) than the Canadian mergansers and other European and North American waterbirds. We found statistically significant positive correlations (MeHg-THg, percent MeHg/THg-MeHg, percent InHg/THg-InHg, THg:Se-THg, MeHg:Se-THg, THg:Se-MeHg, MeHg:Se-MeHg, InHg:Se-InHg, MeHg:Se-THg:Se) and some negative correlations (percent InHg/THg-MeHg, percent MeHg/THg-InHg, THg:Se-Se, MeHg:Se-Se). As THg and percent MeHg in the studied mergansers were similar to populations living in non-Se-deficient areas, it is likely that different mechanisms of muscle Hg detoxification have evolved in mergansers populations living in Se-deficient areas. (C) 2013 Elsevier Inc. All rights reserved.
Kalisinska, Elzbieta Gorecki, Jerzy Okonska, Anna Pilarczyk, Bogumila Tomza-Marciniak, Agnieszka Budis, Halina Lanocha, Natalia Kosik-Bogacka, Danuta I. Kavetska, Katarzyna M. Macherzynski, Mariusz Golas, Janusz M.
Keywords: Contaminants; Mergus merganser; Common Merganser

Heavy metals in the brain of long-tailed duck (Clangula hyemalis) wintering in the Pomeranian Bay, Poland - Kalisinska, Elzbieta; Szuberla, Urszula (Biological Trace Element Research, 1996)
Males (n = 34) and females (n = 23) of long-tailed duck (Clangula hyemalis) collected on the southern coast of the Baltic Sea in winter were studied to determine brain tissue concentration of iron (Fe), zinc (Zn), copper (Cu), manganese (Mn), and cadmium (Cd). There were no significant differences in the concentration of metals between males and females, except for Cd, the concentration of which in male brains was twice that of the females. In the brains of 20 birds (41% male and 26% female), the lead (Pb) concentration exceeded 1 mu-g/g wet wt. In all the duck brains examined, Spearman correlation coefficients were significant and positive for Zn-Mn, Cu-Mn, Cu-Fe, and Pb-Fe; a negative correlation was found for Pb-Zn. Additionally, female brains showed a positive correlation between Pb and Fe. The results obtained were compared with literature data for diving and nondiving anseriforms and birds of other taxa. It seems that concentration of heavy metals in the brain tissue of birds reflect natural adaptations (e.g., for diving) as well as effects of environmental pollution.
Keywords: Nonbreeding Seasons; Clangula hyemalis; Long-tailed Duck; Contaminants

Interspecific kleptoparasitism by four species of gull Larus spp. in South Sweden - Kallander, Hans (Ornis Svecica, 2006)
Data are presented on interspecific kleptoparasitism by Black-headed Gull Larus ridibundus, Common Gull L. canus, Herring Gull L. argentatus and Great Black-backed Gull L. marinas, collected in South Sweden from the late 1950s to the present day. The basis for the presentation is the various host species exploited by the four gull species. For each host species, information is given on species of gull kleptoparasitising it, seasonal occurrence of kleptoparasitism, details of behaviour and, when available, data on gulls' success rates. The paper is intended as a sort of catalogue. For this reason, relevant literature is reviewed under each of the host-species headings. Gulls' success rates varied between 55% for Black-headed Gulls and Common Gulls parasitising Northern Lapwings Vanellus vanellus, the most often observed kleptoparasitic association, and 15% on the few occasions that Black-headed Gulls parasitised Curlews Numenius arquata in grassland. When the same two gull species parasitised Common Starlings Sturnus vulgaris, their success rate varied with robbing tactic used (16% vs Abstract 45%). Beside the association of the two small gull species with Lapwings and Golden Plovers Pluvialis apricaria, the most frequently observed associations were those of Herring Gulls with Common Eiders Somateria mollissima and Great Black-backed Gulls and Herring Gulls with diving fish-eaters (Great Cormorant Phalacrocorax carbo, mergansers Mergus spp.). Kleptoparasitism often occurred during periods of food scarcity, being most common in harsh winter conditions (the two large gull species) and during cold spells in early spring (some associations of the two small gull species). As in other studies, gulls' success rate was strongly dependent on the size of hosts' prey, and thus, normally on handling time. It is suggested that success rate can often be used as a substitute for profitability in studies of kleptoparasitism.
Keywords: Common Eider; Nonbreeding Seasons; Somateria mollissima; Trophic Interactions; Common merganser; Mergus merganser

Avian Wildlife Reservoir of Campylobacter-Fetus-Ssp-Jejuni Yersinia-Spp and Salmonella-Spp in Norway - Kapperud, G.; Rosef, O. (Applied and Environmental Microbiology, 1983)
Cloacal swabs from 540 wild-living birds were cultured for C. fetus ssp. jejuni, Yersinia spp. and Salmonella spp. The carrier rates detected were as follows: C. fetus ssp. jejuni, 28.4%; Yersinia spp., 1.2%; and Salmonella spp., 0.8%. All birds were apparently healthy when captured. C. fetus ssp. jejuni was isolated from 11 of the 40 bird species examined. Among birds inhabiting the city of Oslo, the highest isolation rate was found in crows (Corvus corone cornix) (89.8%), followed by gulls (Larus spp.) (50.0%) and domestic pigeons (Columba livia domestica) (4.2%). The gulls and crows scavenge on refuse dumps. High carrier rates were also detected among the following birds from nonurban, coastal areas: puffin (Fratercula arctica), (51.3%), common tern (Sterna hirundo) (5.6%), common gull (L. canus) (18.9%), black-headed gull (L. ridibundus) (13.2%) and herring gull (L. argentatus) (4.2%). The list of species harboring C. fetus ssp. jejuni also includes the Ural owl (Strix uralensis), goldeneye (Bucephala clangula) and reed bunting (Emberiza schoeniclus). The following 5 Yersinia strains were isolated: Y. kristensenii (2 strains), Y. intermedia (2 strains) and Yersinia X2 (1 stain). Four Salmonella strains were isolated from 3 different species of gulls. These isolates were identified as S. typhimurium, S. indiana and S. djugu. The results indicate that campylobacters are a normal component of the intestinal flora in several bird species whereas Salmonella and Yersinia carriers are more sporadic.
Keywords: Bucephala clangula; Common Goldeneye; Disease

First Record of a Hooded Merganser Nest in a Red-cockaded Woodpecker Cavity - Kappes, J. J. (SOUTHEASTERN NATURALIST, 2020)
Dryobates borealis (Red-cockaded Woodpecker) is considered a keystone cavity excavator, endemic to the fire-maintained Pinus (pine) forests of the southeastern US. This species excavates its roost and nest cavities in living pines. Larger woodpecker species sometimes enlarge these cavities, rendering the holes unsuitable for the Red-cockaded Woodpecker but suitable for larger cavity-nesting species. Here I report the first record of a Lophodytes cucullatus (Hooded Merganser) nesting in such a cavity at the Brosnan Forest on the Coastal Plain of South Carolina. In previous annual spring censuses, this enlarged Red-cockaded Woodpecker cavity was occupied by Aix sponsa L. (Wood Duck) (3 censuses), Sciurus niger (Fox Squirrel) (2 censuses), and a Pantherophis alleghaniensis (Eastern Rat Snake) (1 census).
Times Cited in Web of Science Core Collection: 1 Total Times Cited: 1 Cited Reference Count: 8

Heavy Metals Cadmium Copper Lead and Mercury in Common Eiders Somateria-Mollissima from Denmark - Karlog, O.; Elvestad, K.; Clausen, B. (Nordisk Veterinaermedicin, 1983)
The Cd, Cu, Pb and Hg content in livers and kidneys of Danish eiders was determined. Toxic levels of Pb were found in some of the birds, and the liver Cd content seemed high from a consumer's point of view.
Keywords: Common Eider; Contaminants; Somateria mollissima

Year-round spatiotemporal distribution pattern of a threatened sea duck species breeding on Kolguev Island, south-eastern Barents Sea - Karwinkel, T.; Pollet, I. L.; Vardeh, S.; Kruckenberg, H.; Glazov, P.; Loshchagina, J.; Kondratyev, A.; Merkel, B.; Bellebaum, J.; Quillfeldt, P. (BMC ECOLOGY, 2020)
Background The long-tailed duck (Clangula hyemalis) was categorized as ' Vulnerable` by the IUCN after a study revealed a rapid wintering population decline of 65% between 1992-1993 and 2007-2009 in the Baltic Sea. As knowledge about the European long-tailed duck's life cycle and movement ecology is limited, we investigate its year-round spatiotemporal distribution patterns. Specifically, we aimed to identify the wintering grounds, timing of migration and staging of this population via light-level geolocation. Results Of the 48 female long-tailed ducks tagged on Kolguev Island (western Russian Arctic), 19 were recaptured to obtain data. After breeding and moulting at freshwater lakes, ducks went out to sea around Kolguev Island and to marine waters ranging from the White Sea to Novaya Zemlya Archipelago for 33 +/- 10 days. After a rapid autumn migration, 18 of 19 birds spent their winter in the Baltic Sea and one bird in the White Sea, where they stayed for 212 +/- 3 days. There, they used areas known to host long-tailed ducks, but areas differed among individuals. After a rapid spring migration in mid-May, the birds spent 23 +/- 3 days at sea in coastal areas between the White Sea and Kolguev Island, before returning to their freshwater breeding habitats in June. Conclusions The Baltic Sea represents the most important wintering area for female long-tailed ducks from Kolguev Island. Important spring and autumn staging areas include the Barents Sea and the White Sea. Climate change will render these habitats more exposed to human impacts in the form of fisheries, marine traffic and oil exploitation in near future. Threats that now operate in the wintering areas may thus spread to the higher latitude staging areas and further increase the pressure on long-tailed ducks.
Times Cited in Web of Science Core Collection: 5 Total Times Cited: 6 Cited Reference Count: 97
Keywords: Conservation; Clangula hyemalis; Long-tailed duck; MOVEMENTS; CLANGULA-HYEMALIS; LONG-TAILED DUCKS; BYCATCH; SEABIRDS; GILLNET FISHERIES; EIDERS; Sea duck; Baltic Sea; MIGRATION; Geolocation; MARKING; NUMBERS; Russian Arctic

Population trends of common wintering waterfowl in Japan: participatory monitoring data from 1996 to 2009 - Kasahara, Satoe; Koyama, Kazuo (Ornithological Science, 2010)
We analyzed population trends of 13 waterfowl (Anseriformes) species wintering in Japan during a 14-year period (1996-2009). We used data from annual volunteer-participatory waterfowl count surveys which were conducted in Japan by the Ministry of the Environment and local prefectural governments. Population indices and long-term trends of each species were calculated using TRIM (TRends and Indices for Monitoring data). TRIM is a freeware program developed for analysis of time series count data with missing observations. During the 14 years, seven species exhibited significant long-term declines, while four species showed long-term increases. Most of the species that showed long term declines were characterized as being water-surface foraging species, species breeding in both middle and high latitude regions, or species using rice fields. Most species that showed long-term increases were characterized as diving species, species breeding at high latitude or species rarely using rice fields. We calculated composite indices for these groups. The group of water-surface foraging species showed declines in river, natural lakes and artificial lakes, except reservoirs, when each habitat was analyzed separately. In contrast, the group of diving foraging species showed an increase in estuarine habitat. We suggest that changes in: water quality, breeding habitat in the middle latitude region, and in cultivation methods in rice fields, have affected population changes of some species and groups.
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons

Removal of medium-sized predators and the breeding success of ducks in Finland - Kauhala, Kaarina (Folia Zoologica, 2004)
A predator removal study was done in Finland to reveal the possible effects of mammalian predators on the breeding success of ducks. Predator removal/protection from hunting was most effective in northern Finland. Also in eastern Finland predator removal had sonic influence on predator numbers, whereas its impact on predator numbers was not so evident in southern Finland. In southern Finland, no increase in the breeding success of ducks was observed in the predator removal area, whereas in northern Finland the relative reproduction rate of diving ducks increased in the removal area and that of dabbling ducks declined in the control area. In eastern Finland, the breeding success of ducks declined in both areas. There was a positive relationship between the raccoon dog index and the relative reproduction rate of dabbling ducks in southern Finland, indicating that raccoon dog numbers probably are of minor importance for the breeding success of ducks. On the contrary. there was a negative relation-ship between the fox and marten indices and the breeding success of ducks in some areas. Marten and fox removal may thus have a positive effect on the breeding success of ducks in Finland. The effect of the American mink could not be verified in this study.
Keywords: Breeding Season; Sea Ducks - General; Productivity; Trophic Interactions

Factors affecting changes in waterfowl populations in eutrophic wetlands in the Finnish lake district - Kauppinen, Jukka; Vaananen, Veli-Matti (Wildlife Biology, 1999)
From the 1970s to the 1990s, changes in breeding waterfowl populations were monitored at 26 well-vegetated lakes in southern Finland. Extreme total population levels were found to differ by 40%, but between successive years fluctuations did not exceed 20%, the most unstable populations being garganey Anas querquedula, tufted duck Aythya fuligula, coot Fulica atra and pochard Aythya ferina. Multiple regression analysis was used to determine the effects of weather factors during wintering, spring and brood seasons on the variation in breeding waterfowl populations. The following weather factors were statistically significant in explaining fluctuations observed in four species; in garganey: spring temperature; in pintail Anas acuta: brood season temperature, winter severity in France and spring temperature; in goldeneye Bucephala clangula: winter severity in the Baltic and spring temperature; and in mallard Anas platyrhynchos: brood season temperature of the previous year. Mallard, teal Anas crecca, wigeon Anas penelope and goldeneye were shot in larger numbers than would be expected considering their respective proportions of the breeding waterfowl community. Hunting pressure on mallard, tufted duck and goldeneye was clearly higher in our study area than in other parts of Finland. Our results indicate that the level of hunting pressure in our study area may affect population densities of mallard.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Sea Ducks - General

Distraction displays made by female common eiders, Somateria mollissima borealis, in response to human disturbance - Kay, Maureen F.; Gilchrist, H. Grant (Canadian Field-Naturalist, 1998)
A high frequency of distraction displays was observed among Common Eiders (Somateria mollissima borealis) nesting on an island in East Bay, Southampton Island, Northwest Territories. Although this anti-predator behavior is common among ground-nesting birds, it appears to be rare among Common Eiders. This may be because Common Eiders nest on offshore islands where terrestrial predators are limited and/or because this type of behaviour increases the risk of predation for the female. Eiders at the East Bay colony, however, are subjected to Arctic Foxes (Alopex lagopus) during egg-laying and early incubation and this may have influenced the frequency with which distraction display behaviors are expressed.
Keywords: Behavior; Breeding Season; Common Eider; Somateria mollissima

The Adaptive Significance of Creching Behavior in the White-Winged Scoter Melanitta-Fusca-Deglandi - Kehoe, F. P. (Canadian Journal of Zoology, 1989)
I tested several hypotheses regarding the adaptive significance of creching behaviour using white-winged scoters (Melanitta fusca delgnadi) at Redberry Lake, Saskatchewan [Canada]. Scoter creches consist of a single female tending the young of one or more conspecifics. There was no relationship between a female's weight at the end of incubation and whether she stayed with ducklings. Therefore, there is no evidence that females in poor condition abandon their young more frequently than other females. No relationship was found between a female's age and her association with ducklings. Therefore, creching does not appear to be related female age or experience. Observations of color-marked ducklings in 1985 showed that 7 out of 10 females tended creches that were composed entirely of forestered young. The survival of ducklings from large groups was greater than that from small groups, so creching does not appear to be a strategy that enhances individual fitness of creche-tending females. However, because of the high degree of philopatry by female scoters, creching could enhance inclusive fitness if creches contain the young of related individuals. This hypothesis could not be tested.
Keywords: Behavior; Breeding Season; Melanitta fusca; White-winged Scoter

Survival and Longevity of White-Winged Scoters Nesting in Central Saskatchewan Canada - Kehoe, F. P.; Brown, P. W.; Houston, C. S. (Journal of Field Ornithology, 1989)
Female white-winged scoters (Melanitta fusca) banded at Redberry Lake, Saskatchewan, have an annual survival rate of 78.2 .+-. 2.0%. One female captured in July 1985 was at least 18 yr old, a new longevity record for the species.
Keywords: Breeding Season; Melanitta fusca; White-winged Scoter; Survival

The Goosander Mergus merganser population breeding in the Alps and its connections to the rest of Europe - Keller, Verena (Wildfowl, 2009)
The main range of the Goosander Mergus merganser in Europe stretches from Norway to northern Russia. Outside this main range, breeding populations exist in Iceland, Britain and the Balkans. In the Alps, the birds breed mainly in Switzerland and southern Germany (Bavaria). This paper compiles evidence from different disciplines to determine the conservation status of the Central-West European (Alpine) population of Goosander, in particular whether it is isolated from other Goosander populations. Recoveries of ringed birds showed that the Goosanders breeding in the Alpine region, estimated at c. 1,000-1,400 pairs in 1998, are augmented by birds from northern Europe during the winter months. Molecular analysis of female-inherited mtDNA indicated a strong genetic differentiation among European breeding populations, whereas no significant differences were found at nuclear DNA markers, indicating at least some interchange between populations. The evidence from the various studies reinforces the view that the Central-West European (Alpine) population of Goosandcr should be considered as a separate population and conservation unit.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Nonbreeding Seasons; Common merganser; Mergus merganser; Population Delineation

Breeding biology of king eiders nesting on Karrak Lake, Northwest Territories - Kellett, Dana K.; Alisauskas, Ray T. (Arctic, 1997)
We studied various aspects of the breeding biology of king eiders (Somateria spectabilis) nesting at Karrak Lake, south of Queen Maud Gulf in the central Canadian Arctic. We found 41 nests distributed among 10 islands in Karrak Lake; to our knowledge, this represents the largest number of king eider nests studied at one site. We suspect that island nesting by king eiders is more common than has been previously reported. King eiders favoured mid-sized islands (0.002-0.081 km-2) over very small (less than 0.002 km-2) or very large (greater than 0.081 km-2) islands. Mean clutch size was 5.4 +- 1.7 (SD) eggs. Apparent nest success was 69.4%, with a composite Mayfield estimate of nest success over egg laying and incubation of 48.7% (95% CI: 47.4-50.0%). Nest success was uncorrelated with date of nest initiation or island size, but eiders nesting on islands farther from the mainland had greater success than those nesting on islands closer to the mainland. Additionally, nest success was greater on islands with more nesting eiders and on islands with nesting arctic terns (Sterna paradisaea).
Keywords: Breeding Season; Productivity; King Eider; Somateria spectabilis

Body-mass dynamics of King Eiders during incubation - Kellett, Dana K.; Alisauskas, Ray T. (Auk, 2000)
Keywords: Breeding Season; King Eider; Somateria spectabilis; Energetics and Nutrition

Nest-site selection, interspecific associations, and nest success of king eiders - Kellett, Dana K.; Alisauskas, Ray T.; Mehl, Katherine R. (Condor, 2003)
We investigated factors influencing nest success in King Eiders (Somateria spectabilis) at Karrak Lake, Nunavut, Canada, during 1995-2001. Island-nesting King Eiders had higher nest success (range 30-89%) than that reported for mainland-nesting populations, and nested at much higher densities (46-198 nests km-2) than on mainland, where they were detected infrequently (usually <1 nest km-2). Predation was the main cause of nest failure, and King Eider nest success was greater on isolated islands (smaller islands, and larger islands farther from the mainland) that were presumably less accessible to mammalian predators. King Eiders did not derive protection from predators by nesting near gulls (Larus spp.) and Arctic Terns (Sterna paradisaea).
Keywords: Breeding Season; Productivity; King Eider; Somateria spectabilis

Body mass of long-tailed ducks (Clangula hyemalis) during incubation - Kellett, Dana K.; Alisauskas, Ray T.; Mehl, Katherine R.; Drake, Kiel L.; Traylor, Joshua J.; Lawson, Shona L. (Auk, 2005)
We investigated body-mass dynamics during incubation of Long-tailed Ducks (Clangula hyemalis) nesting in Canada's central Arctic, 1998-2003. Long-tailed Duck females (n = 37) lost 7% of pre-incubation body mass during incubation; on average, females weighed 618 +/- 15 g (mean SE) at clutch completion and 575 +/- 11 g at hatch. Given the differences in body size, Long-tailed Ducks relied less on endogenous reserves than sympatric King Eiders (Somateria spectabilis), but lost less mass than similar-sized waterfowl species nesting in temperate climates. Preliminary data suggest that Long-tailed Ducks maintain similar or higher nest-attendance rates than temperate-nesting waterfowl of similar size, and we suggest that access to locally abundant, high-quality foods enable Long-tailed Duck females to maintain high incubation constancy without sacrificing female body condition. Nevertheless, Long-tailed Ducks appear to differ widely from most Arctic-nesting waterfowl in nutritional strategy for nesting.
Keywords: Breeding Season; Clangula hyemalis; Long-tailed Duck; Energetics and Nutrition

Modeling spring migration patterns of scoters and loons in the Bay of Fundy - Kelley, J. D.; Major, H. L. (JOURNAL OF FIELD ORNITHOLOGY, 2020)
Populations of scoter and loon species that winter in the Atlantic are understudied in North America, but coastal observatories may provide the data required to fill some of the knowledge gaps. The migration of scoters and loons has been monitored at the Point Lepreau Bird Observatory (PLBO) in the Bay of Fundy every spring since 1996, but little peer-reviewed research based on the resultant database has been published. Using data collected over 18 years at the Bay of Fundy (2000-2017), our objectives were to (1) determine the most accurate method of modeling hourly migration rates for Surf (Melanitta perspicillata), White-winged (M. deglandi), and Black (M. americana) scoters, and Red-throated (Gavia stellata) and Common (G. immer) loons, and (2) assess trends in hourly migration rates for our five focal species to determine if the numbers of migrants passing PLBO have changed over time. We calculated hourly migration rates for each of our five focal species and evaluated drivers (i.e., timing and environmental conditions) of migration and annual trends using zero-inflated generalized linear mixed models (GLMMs). We found that drivers of migration differed among species. Specifically, hourly migration rates decreased with increasing tide height for all species except Red-throated Loons. In addition, hourly migration rates increased with increasing wind vector (i.e., a tailwind) for the three scoter species, but decreased with increasing wind vector for the two loon species. Scoter migration rates peaked daily between 11:00 and 13:00 UTC, but we found no daily peak for either loon species. Peak hourly migration rates of Black and Surf scoters occurred from 12 to 26 April, but migration rates of White-winged Scoters and both loon species continued to increase throughout our migration-monitoring window. Finally, we found no changes in hourly migration rates over time for any of our focal species, suggesting no changes in abundance over the 18 years of data collection. Our study reveals the importance and utility of long-term, coastal observation stations, and we recommend their continued funding and use as valuable sources of monitoring data.
Times Cited in Web of Science Core Collection: 0 Total Times Cited: 0 Cited Reference Count: 44
Keywords: White-winged Scoter; Surf Scoter; SEA; black scoter; Common Loon; Point Lepreau Bird Observatory; Red-throated Loon; spring migration; WIND

Hydroxylated and methoxylated polybrominated diphenyl ethers in a Canadian Arctic marine food web - Kelly, Barry C.; Ikonomou, Michael G.; Blair, Joel D.; Gobas, Frank A. P. C. (Environmental Science & Technology, 2008)
Residues of hydroxylated (OH-) and methoxylated (MeO-) polybrominated diphenyl ethers (PBDEs) have been previously detected in precipitation, surface waters, wildlife, and humans. We report measured concentrations of OH-PBDEs, MeO-PBDEs, and Br-3-Br-7 PBDEs in sediments and biota from a Canadian Arctic marine food web. PBDEs exhibited very low trophic magnification factors (TMFs between 0.1-1.6), compared to recalcitrant PCBs (TMFs between 3 and 11), indicating biotransformation via debromination and/or cytochrome P450 mediated metabolism. OH-PBDEs were not detectable in samples of blood, muscle, and/or liver of fish and marine wildlife. Five OH-PBDEs were detected at very low concentrations (range: 0.01-0.1 ng.g(-1) lipid equivalent) in beluga whale blubber and milk. The data indicate negligible formation/retention of OH-PBDEs in these Arctic marine organisms. Appreciable levels of several MeO-PBDEs were observed in bivalves, Arctic cod, sculpin, seaducks, and beluga whales (mean range 0.1-130 ng.g(-1) lipid equivalent). 2'-MeO-BDE-68 and 6-MeO-BDE-47 exhibited the highest concentrations among the brominated compounds studied (including BDE-47 and BDE-99) and biomagnified slightly in the food web, with TMFs of 2.3 and 2.6, respectively. OH- and MeO-PBDEs in this Arctic marine food web may occur via metabolic transformation of PBDEs or bioaccumulation of PBDE degradation products and/or natural marine products. We observed no evidence of a local natural source of OH- or MeO-PBDEs, as no measurable quantities of those compounds were observed in ambient environmental media (i.e., sediments) or macroalgae. Further investigations of PBDEs and their hydroxylated and methoxylated analogues would be useful to better understand sources, fate, and mechanisms governing biotransformation and bioaccumulation behavior of these compounds.
Keywords: Sea Ducks - General; Contaminants

Echoes of numerical dependence: responses of wintering waterbirds to Pacific herring spawns - Kelly, J. P.; Rothenbach, C. A.; Weathers, W. W. (MARINE ECOLOGY PROGRESS SERIES, 2018)
We investigated the ecological importance of Pacific herring Clupea pallasii spawning activity to wintering waterbird numbers in Tomales Bay, California, USA. Time-series analyses were used to assess the potential dependence of future waterbird abundances on current changes in herring spawning biomass, independent of underlying trends or other dynamics in waterbird numbers or herring activity. Forecasts of winter waterbird abundance were significantly improved by considering the lagged effects of changes in herring spawning biomass. Impulse-response functions provided strong evidence that the dynamics of winter waterbird abundances include 'echoes' of response over time to any unusual pulse of herring activity, with carryover effects leading to sustained increases in waterbird species' abundances over multiple years, and increases in the abundance of all waterbird species (combined) over the subsequent 3 winters. Increases in waterbird abundance consistent with variance-prone responses to the pulsed availability of prey were sustained by periods of conditional variance-aversion associated with subsequent declines in herring spawning biomass to expected long-term levels. Annual spawning activity was highly variable, and when the availability of roe was relatively high, the potential consumption of herring eggs could account for up to 64% of the collective energy needs of waterbirds (all species combined) over the 90 d herring season (mean +/- SE = 20 +/- 3.6%). Several waterbird species shifted their bay distributions in response to herring spawning events within 2 d; however, some species that did not concentrate in spawning areas exhibited sustained annual increases in bay-wide winter abundance in response to increased herring spawning biomass.
Times Cited in Web of Science Core Collection: 1 Total Times Cited: 1 Cited Reference Count: 78
Keywords: BIRDS; Predation; POPULATION; SURF SCOTERS; WHITE-WINGED SCOTERS; Forage fish; CLUPEA-HARENGUS-PALLASI; Estuaries; GEORGIA; METABOLIC-RATE; Pulsed resource; STRAIT; Time series; TOMALES BAY; Variance sensitivity

Distribution, abundance, and implications for conservation of winter waterbirds on Tomales Bay, California - Kelly, John P.; Tappen, Sarah L. (Western Birds, 1998)
We analyzed patterns of abundance and distribution of wintering waterbirds in Tomales Bay, California, on the basis of 21 baywide winter surveys over 7 years from 1989-90 to 1995-96. Total waterbird abundances averaged 21,943 (min. 14,842, max. 25,553), excluding shorebirds and gulls. Mean waterbird density was 770 birds/km2 with the greatest concentrations along the east shore and between Pelican and Tom's points. The Surf Scoter, Bufflehead, and Greater Scaup together accounted for 70% of the total waterbirds. Aerial count data from the U.S. Fish and Wildlife Service Midwinter Waterfowl Survey underestimated the numbers of waterbirds in comparison to our counts made from boats. Such differences adjusted for, our abundance estimates for scoters and Bufflehead appear similar to other abundances reported in the 1960s and 1970s. Compared to other coastal wetlands in California, Tomales Bay provides particularly important winter habitat for the Red-throated and Common loon, Eared and Horned grebe, Black Brant, Surf and Black scoter. Except for San Francisco Bay, Tomales Bay may provide the most important winter habitat for the Bufflehead on the Pacific coast south of the Columbia River. Waterbird distributions on Tomales Bay are associated with a dynamic array of habitat conditions. Increasing human activities in Tomales Bay and its watershed interact with these processes and conditions and suggest several concerns for conservation of winter waterbirds. Protection of waterbird populations will require particular attention to the control of human disturbance, protection of eelgrass beds, the possible effects of the herring fishery and aquaculture, and management of processes in the watershed.
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons

Predicting the effects of marine climate change on the invertebrate prey of the birds of rocky shores - Kendall, Michael A.; Burrows, Michael T.; Southward, Alan J.; Hawkins, Stephen J. (Ibis, 2004)
By the end of the 21st century models of climate change predict that the air temperature over most of the British Isles will increase by between 2 and 3degreeC and sea-level will rise by 40-50 cm. Over that period it will become windier and mean wave height will increase, as will the frequency of storms. These changes in climate and weather will impact the intertidal zone of the UK and will cause distribution changes in many of the common invertebrate species that live there. Where these changes are severe they may well impact on patterns of distribution of ducks and wading birds. In the British Isles a number of organisms live close to their geographical limits of distribution. Some of these species might be expected to extend their range as climatic restraints are relaxed. Species currently limited by cool summers or winter cold will move northwards. In most cases the effects on the distribution of waterbirds will be small. For example, the replacement of the Northern Limpet Patella vulgata by the Southern Limpet P. depressa is unlikely to adversely affect Eurasian Oystercatchers Haematopus ostralegus. Of wider concern is the possibility that as climate warms the abundance and productivity of brown algae will decrease. This is likely to have two significant effects for waders. First, it would represent a loss of potentially rich feeding grounds for species such as Ruddy Turnstone Arenaria interpres that feed on small easily desiccated invertebrates living on or below the seaweed. Secondly, as algae die or are broken away the resulting debris is exported to sediment habitats where it considerably boosts the in situ production of bacteria at the base of the food web. An increase in sea-level will only have a major impact on the extent of rocky shore invertebrate communities where shore topography prevents the upward migration of the biota. Where a seawall limits shores, for example, biological production will be curtailed as the area available for colonization decreases. Increases in the size of waves and the frequency of storms will mimic increasing exposure and there will be a significant reduction in algal production in areas that are affected.
Keywords: Sea Ducks - General; Trophic Interactions

Notes on Hooded Merganser Nests in the Coastal Plain of South Carolina USA - Kennamer, R. A.; Harvey, W. F. Iv; Hepp, G. R. (Wilson Bulletin, 1988)
Keywords: Breeding Season; Hooded Merganser; Lophodytes cucullatus

Fish-eating abundance in oligotrophic lakes in Kejimkujik National Park, Nova Scotia, Canada - Kerekes, J.; Tordon, R.; Nieuwburg, A.; Risk, L. (Hydrobiologia, 1994)
Aquatic bird population data in 40 oligotrophic lakes and ponds in Nova Scotia, Canada indicates that only lakes gt 20 ha support territorial pairs of Common Loon (Gavia immer) and only lakes gtoreq 40 ha produce their young. Broods of Common Merganser (Mergus merganser americanus) occurred in lakes gt 25 ha and loon and merganser broods together occurred only in lakes gtoreq 80 ha. The fish production in the lakes was estimated from the total phosphorus vs fish yield relationship obtained in similar, oligotrophic lakes in Ontario. Considering the fish consumption and mergansers until fledging along with the maintenance of the adults during the same period (about 200 and 130 kg fish respectively) and the estimated fish production in these lakes, there is a close balance between the size of water body and its fish production to the occupancy and production of piscivorous birds.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Common merganser; Mergus merganser

Disappearance of the Steller's Eider from the Yukon-Kuskokwim Delta Alaska - Kertell, K. (Arctic, 1991)
Keywords: Breeding Season; Abundance, Distribution, and Trends; Polysticta stelleri; Steller's eider

Survival of reared Atlantic salmon (Salmo salar) smolts during downstream migration and its timing: a case study in the Pirita River - Kesler, M.; Vetemaa, M.; Saks, L.; Saat, T. (Boreal Environment Research, 2013)
Times Cited: 0 Kesler, Martin Vetemaa, Markus Saks, Lauri Saat, Toonrias 0
Keywords: Trophic Interactions; Common merganser; Mergus merganser

Influence of petroleum hydrocarbons on the endoparasitic helminths of the common eider, Somateria mollissima, from Newfoundland - Khan, R. A.; Chandra, C. V.; Earle, P. J.; Robertson, G. J.; Ryan, P.; Jamieson, S. (Journal of Helminthology, 2011)
Times Cited: 0 Khan, R. A. Chandra, C. V. Earle, P. J. Robertson, G. J. Ryan, P. Jamieson, S. 0
Keywords: Nonbreeding Seasons; Contaminants; Parasites; Common eider; somateria mollissima

Repeated territorial attacks of pied-billed grebe on ring-necked duck - Kilham, Lawrence (Wilson Bull, 1954)
The report of an attack by a male Pied-billed Grebe (Podilymbus podiceps) on a female Ring-neck Duck (Aythya collaris). Coots (Fulica americana), Blue-winged Teal (Anas discors). and Wood Ducks (Aix sponsa) were present but were not molested. However, a female Hooded Merganser (Lophodytes cucullatus) was also attacked from below and threatened from the surface during one observational period. || ABSTRACT AUTHORS: T. W. Porter
Keywords: Behavior; Breeding Season; Hooded Merganser; Lophodytes cucullatus

Habitat-specific clutch size and cost of incubation in common eiders, Somateria mollissima - Kilpi, Mikael; Lindstrom, Lai (Oecologia (Berlin), 1997)
Common eiders, Somateria mollissima, breed on two types of island in the Northern Baltic: open, sparsely vegetated islands and wooded islands with dense mixed forests. On open islands 79.8% of the nests were on open cliffs, exposed to wind and rain whereas on wooded islands 91.7% of the nests were sheltered inside dense spruce and pine thickets. We found that clutch size on open islands was significantly smaller than on wooded islands. Females started breeding simultaneously in the two habitats and they were similar in body size as measured by the length of the radio-ulna. During incubation females on open islands lost weight at a faster rate than females on wooded islands (34 g/day and 19 g/day, respectively). Heat loss is faster on open than wooded islands and therefore we suggest that the faster weight loss of females on open islands result from thermodynamically adverse incubation conditions. Because the eider is an 'extreme capital breeder, energy used for egg production cannot be used for incubation. To sustain a higher incubation cost on open islands, the optimal clutch size is therefore lower than on wooded islands.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Energetics and Nutrition; Habitat

Metal accumulation in tissues of seabirds from Chaun, Northeast Siberia, Russia - Kim, Eun-Young; Ichihashi, Hideki; Saeki, Kazutoshi; Atrashkevich, Gennady; Tanabe, Shinsuke; Tatsukawa, Ryo (Environmental Pollution, 1996)
Concentrations of four essential elements (Fe, Mn, Zn, and Cu) and two toxic metals (Cd and Hg) were determined in selected tissues of 11 seabird species collected in Chaun, northeast Siberia. In oldsquaw, arctic tern and herring gull, zinc concentrations were correlated with Cd concentrations. Cadmium concentrations in all the species were highest in kidney and Hg in liver. Cd levels in the liver and kidney of herring gulls were higher than those observed from other breeding areas. Similarly, Hg concentrations were also high in the liver of herring gull. High concentrations of Cd and Hg found in some birds from Chaun might have arisen from exposure on migration.
Keywords: Breeding Season; Clangula hyemalis; Long-tailed Duck; Contaminants

Mercury levels and its chemical form in tissues and organs of seabirds - Kim, E. Y.; Murakami, T.; Saeki, K.; Tatsukawa, R. (Archives of Environmental Contamination and Toxicology, 1996)
Liver, muscle, kidney, and feather samples from nine species of seabirds were analyzed for total and organic (methyl) mercury (MM). Total mercury (TM) levels in liver showed great intra- and inter-species variations, with the concentrations varied from 306 mu-g/g (dry weight) in black-footed albatross (Diomedea nigripes) to 4.9 mu-g/g in arctic tern(Sterna paradisaea), while MM levels were less relatively variable. The order of MM concentrations in tissues of all the seabirds except oldsquaw (Clangula hyemalis) was as follows: liver gt kidney gt muscle. The mean percentage of MM in total was 35%, 36%, and 66% in liver, kidney, and muscle, respectively, for all the species. Statistically significant negative correlations were found between the proportion of MM to TM and concentrations of TM in the liver and muscle of black-footed albatross and in the liver of laysan albatross. Further-more, the percentage of MM decreased with an increase in TM concentrations in the liver, muscle, and kidney of all the species. Black-footed albatross had the highest concentration and burden of mercury in the liver, wherein more than 70% of the TM occurred as inorganic mercury. On the other hand, the mercury burdens in feathers were less than 10% of the body burdens, indicating that excretion of mercury by moulting is negligible. The results suggest that some seabirds are capable of demethylating MM in the tissues (mainly in liver), and store mercury as an immobilizable inorganic form in the liver. It is noteworthy that the species with a high degree of demethylation capacity and slow moulting pattern showed low mercury burdens in feathers.
Keywords: Clangula hyemalis; Long-tailed Duck; Contaminants

Acute and chronic increases in predation risk affect the territorial behaviour of juvenile Atlantic salmon in the wild - Kim, J. W.; Wood, J. L. A.; Grant, J. W. A.; Brown, G. E. (Animal Behaviour, 2011)
Times Cited: 3 Kim, Jae-Woo Wood, Jacquelyn L. A. Grant, James W. A. Brown, Grant E. Brown, Grant/B-7182-2013 Brown, Grant/0000-0003-3493-3477 3
Keywords: Breeding Season; Trophic Interactions; Common merganser; Mergus merganser

Feeding Behavior of Buffleheads - King, B. (British Birds, 1976)
Keywords: Behavior; Bucephala albeola; Bufflehead

Parasite Transmission Stages in Feces of Common Eiders Flushed from their Nests - King, Jenelle D.; Shutler, Dave (Northeastern Naturalist, 2010)
Several species of ducks defecate when flushed from their nests, but it is unclear why. Possibly, this ehavior reflects manipulation by parasites to facilitate transmission. We analyzed feces of 32 incubating Somateria mollissima (Common Eider) for evidence of parasite transmission stages. We found a total of only 11 parasite transmission stages (identified as digenean and nematode eggs) in feces of 3 different hens, suggesting that defecation around the nest has a low probability of leading to parasite transmission. Other hypotheses for defecation behavior in this and other duck species (repulsion of egg predators, weight loss to increase hen maneuverability to escape predators) appear insufficient to explain its persistence.
Keywords: Behavior; Breeding Season; Common Eider; Somateria mollissima; Parasites

Index numbers for waterbird populations. III. Long-term trends in the abundance of wintering wildfowl in Great Britain, 1966/67-1991/92 - Kirby, J. S.; Salmon, D. G.; Atkinson-Willes, G. L.; Cranswick, P. A. (Journal of Applied Ecology, 1995)
1. A new approach to estimating the relative size (indexing) of waterbird populations was applied to monthly counts for 17 wildfowl species obtained over 26 winter seasons from 1966/67 to 1991/92. 2. The wetland count units included in the index computations were those with at least 50% of the potential counts available. All index numbers were based on these count units, and on the winter months of maximum abundance for each species, ascertained by examination of monthly indices. 3. A mean of 69% (37-99%) of the maximum species count for the whole of Britain in 1991-92 was present on the count units included in the indexing process, and thus the indices were applicable to the counted population. Compared to total British population estimates, the count units selected supported relatively high proportions ( gt 56%) of the total populations of 10 of the 17 species considered. Thus, most index numbers were considered to be representative of the whole population. 4. Spectacular and sustained increases were apparent for the Bewick's swan, Canada goose, dark-bellied brent goose and gadwall, and less dramatic, though sustained, increases were found for four species of ducks (teal, shelduck, redbreasted merganser and goosander). Populations of the two remaining swans (mute swan and whooper swan) had undergone sharp increases since the mid-1980s, whilst those for four further duck species (pintail, shoveler, tufted duck and goldeneye) had increased sharply during the mid to late-1960s and have increased or decreased slightly subsequently. The pochard population appears to be smaller now than it was in the early and mid-1970s, whilst that for mallard was relatively stable. Index numbers for wigeon were variable, with no obvious trend. 5. The index numbers for goosander implied that the population follows a regular cycle, with winters of peak abundance separated by three or four winters of low, and often, decreasing numbers. 6. The reliability of the index numbers is discussed together with trends for individual species, recent changes in European populations and possible causal factors.
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons

Waterfowl Losses Caused by Fishery at the Baltic Coast of Schleswig-Holstein West Germany - Kirchhoff, K. (Vogelwelt, 1982)
During 4 winters (1977/1978-1980/1981) 6 fishing places which comprised 19.3% of the fleet were controlled on 552 occasions to calculate the waterfowl losses caused by fishery activities. Almost all waterfowl drowned in set nets. The calculation resulted in a minimum of 15,000 individuals/winter (9400 eiderducks, 2600 common scoters and 1200 tufted ducks). Most waterfowl drown in Nov. (32%), 64% in the 1st half of the winter. The results are discussed regarding the size of the populations. The losses caused by fisheries have to be kept in mind when discussing measures interfering with populations.
Keywords: Conservation; Common Eider; Nonbreeding Seasons; Somateria mollissima; Black Scoter; Melanitta nigra

Morphology and density of mussels on natural and aquaculture structure habitats: implications for sea duck predators - Kirk, Molly; Esler, Daniel; Boyd, W. Sean (Marine Ecology Progress Series, 2007)
We compared density and morphology of wild mussels Mytilus trossulus growing naturally on shellfish farming structures to that of mussels from nearby intertidal areas, and considered the relevance to molluscivorous sea ducks. Mussel density on aquaculture structures greatly exceeded that of intertidal areas and farm mussels were larger, had lower shell mass, and had weaker byssal attachments. Differences in environmental conditions and predation regimes throughout the summer growing season were likely responsible for these differences. These morphological and density differences, in turn, have important implications for their primary winter predators, sea ducks, including surf scoters Melanitta perspicillata and Barrow's goldeneyes Bucephala islandica. Higher levels of mussel depletion in farm habitats and strong associations of ducks with shellfish farms indicate that sea ducks responded to this novel, profitable prey resource. Our results support recent research that indicates that artificial structures introduced into coastal areas create novel marine habitats that can support unique communities of epibiota. That sea ducks appear to profit from the introduction of aquaculture structures is evidence of a positive effect of anthropogenic modifications in a coastal environment.
Keywords: Conservation; Nonbreeding Seasons; Melanitta perspicillata; Surf Scoter; Trophic Interactions; Habitat; Barrow's Goldeneye; Bucephala islandica

Movements of wintering surf scoters: predator responses to different prey landscapes - Kirk, Molly; Esler, Daniel; Iverson, Samuel A.; Boyd, W. Sean (Oecologia (Berlin), 2008)
The distribution of predators is widely recognized to be intimately linked to the distribution of their prey. Foraging theory suggests that predators will modify their behaviors, including movements, to optimize net energy intake when faced with variation in prey attributes or abundance. While many studies have documented changes in movement patterns of animals in response to temporal changes in food, very few have contrasted movements of a single predator species naturally occurring in dramatically different prey landscapes. We documented variation in the winter movements, foraging range size, site fidelity, and distribution patterns of a molluscivorous sea duck, the surf scoter (Melanitta perspicillata), in two areas of coastal British Columbia with very different shellfish prey features. Baynes Sound has extensive tidal flats with abundant clams, which are high-quality and temporally stable prey for scoters. Malaspina Inlet is a rocky fjord-like inlet where scoters consume mussels that are superabundant and easily accessible in some patches but are heavily depleted over the course of winter. We used radio telemetry to track surf scoter movements in both areas and found that in the clam habitats of Baynes Sound, surf scoters exhibited limited movement, small winter ranges, strong foraging site fidelity, and very consistent distribution patterns. By contrast, in mussel habitats in the Malaspina Inlet, surf scoters displayed more movement, larger ranges, little fidelity to specific foraging sites, and more variable distribution patterns. We conclude that features associated with the different prey types, particularly the higher depletion rates of mussels, strongly influenced seasonal space use patterns. These findings are consistent with foraging theory and confirm that predator behavior, specifically movements, is environmentally mediated.
Keywords: Behavior; Nonbreeding Seasons; Melanitta perspicillata; Surf Scoter; Dispersal; Habitat; SDJV funded

Foraging effort of Surf Scoters (Melanitta perspicillata) wintering in a spatially and temporally variable prey landscape - Kirk, Molly K.; Esler, Daniel; Boyd, W. Sean (Canadian Journal of Zoology, 2007)
We monitored foraging effort of radio-tagged Surf Scorers (Melanitta perspicillata (L., 1758)) in three different habitats: (1) shellfish farm structures with high densities of mussels and strong seasonal prey depletion, (2) soft-bottom clam beds with more stable but less available prey, and (3) rocky intertidal beds with moderate mussel densities and depletion rates. We predicted that foraging effort would vary uniquely by habitat, with effort increasing more where depletion was strongest. However, variation in both hourly and daily foraging efforts was best explained by date only. Effort per hour was lowest in early December (presumably owing to very high prey abundance), increased until mid-February as prey declined, and then decreased again in March (probably owing to increased daylight time for foraging). Foraging effort estimated over a full day increased steadily from December to March as prey were depleted. Temporal patterns of effort did not vary by habitat after accounting for seasonal effects. Instead of increasing foraging effort in habitats with strong depletion, Surf Scoters redistributed, to habitats with lower degrees of prey reduction as the season progressed. We suggest that Surf Scoters; respond to variation in prey by adjusting both foraging effort and habitat selection as the prey landscape changes.
Keywords: Behavior; Nonbreeding Seasons; Melanitta perspicillata; Surf Scoter; Trophic Interactions

On the biology of the Spectacled Eider - Kistchinski, A. A.; Flint, V. E. (Wildfowl, 1974)
Keywords: Breeding Season; Somateria fischeri; Spectacled Eider

Brood Habitat of the Hooded Merganser - Kitchen, D. W.; Hunt, G. S. (Journal of Wildlife Management, 1969)
Keywords: Breeding Season; Hooded Merganser; Lophodytes cucullatus

Changes in distribution and abundance of submerged macrophytes in the Inner Bay at Long Point, Lake Erie: Implications for foraging waterfowl - Knapton, Richard W.; Petrie, Scott A. (Journal of Great Lakes Research, 1999)
Submerged aquatic macrophytes in Long Point Bay provide food for several species of migrating waterfowl, particularly diving ducks. The percent occurrence of several plant species in the diets of six species (207 birds) of diving ducks were studied between 1992 and 1994. Of 29 plant species consumed, Vallisneria americana was the most commonly occurring in the diet. Chara vulgaris, Potamogeton spp., Polygonum spp., and Najas flexilis/quadalupensis were also important dietary items. The seeds of a number of emergent macrophyte species were also consumed. Submerged macrophytes were sampled at 312 locations in the Inner Bay of Long Point, Lake Erie, in 1991, 1992, and 1995. Distribution and percent abundance were compared with a similar study in 1976 and with observations of macrophytes in 1962. In comparison with the 1976 study, Chara vulgaris is still dominant over much of the Bay. V. americana and N. flexilis/N. guadalupensis have expanded their ranges, probably a result of increasing light penetration associated with the filtering of suspended material by introduced zebra mussels Dreissena polymorpha. The continued widespread distribution of C. vulgaris, and the expansion of V. americana and N. flexilis/N. guadalupensis, has probably benefitted waterfowl, as these species have a high nutritive value and are readily consumed by diving ducks at Long Point. Myriophyllum spicatum, an exotic species introduced in the early 1970s, increased in distribution between 1976 and 1991 but decreased in distribution and percent abundance by 1995. Increased light transparency may have contributed to this decline, as M. spicatum typically grows best in turbid, eutrophic environments. The decline of this species has probably been beneficial to waterfowl because it commonly out-competes native plants and it is underutilized by ducks at Long Point. Ceratophyllum demersum appears to be a more prominent member of the submerged macrophyte communities in the 1990s, as it was not reported previously. In comparison with 1962, major changes have occurred in species composition and relative abundance: M. spicatum, Najas spp., and Elodea canadensis have increased, Potamogeton spp. and Nitella spp. have declined. Macrophyte distribution and abundance on the Inner Bay is influenced by environmental, biological, geomorphological and geological variables. However, the anthropogenic introduction of two exotic species, M. Spicatum and the zebra mussel, appears to have had a pronounced influence on the community structure of submerged macrophytes in Long Point Bay.
Keywords: Sea Ducks - General; Habitat

Further evidence for site fidelity to wing molt locations by king eiders: Integrating stable isotope analyses and satellite telemetry - Knoche, Michael J.; Powell, Abby N.; Quakenbush, Lori T.; Wooller, Matthew J.; Phillips, Laura M. (Waterbirds, 2007)
Studies using stable-isotope analyses of feathers to determine molt locations in marine birds are increasingly common but generally lack verification through ground-truthing. In this study, we examined the stable isotope compositions of wing feathers from King Eiders (Somateria spectabilis) implanted with satellite-transmitters. We compared stable carbon, nitrogen, and hydrogen isotope compositions (delta C-13, delta N-15, and delta D, respectively) of primary feathers with the geographic location of wing molt in the subsequent year. Longitude of molt locations of ciders was highly correlated with delta C-13 (r(2)= 0.69, N = 12) and delta D (r(2)= 0.90, N = 12) isotope values from their primary feathers grown in the previous year. There was no relationship between delta N-15 and location of wing molt (r(2) = 0.007, N = 12). The results of this study provide further evidence for site fidelity during wing molt by King Eiders.
Keywords: Nonbreeding Seasons; Molt; King Eider; Somateria spectabilis; Dispersal; Techniques

Bufflehead breeding activity in south-central North Dakota - Knutsen, Gregory A.; King, Janet C. (Prairie Naturalist, 2004)
Keywords: Breeding Season; Bucephala albeola; Bufflehead

The Bufflehead Bucephala-Albeoia a New Host Record for Plasmodium - Kocan, R. M.; Knisley, J. O. Jr (Journal of Wildlife Diseases, 1971)
Keywords: Bucephala albeola; Bufflehead; Parasites

Trichobilharzia mergi sp nov (Trematoda: Digenea: Schistosomatidae), a visceral schistosome of Mergus serrator (L.) (Aves: Anatidae) - Kolarova, L.; Skirnisson, K.; Ferte, H.; Jouet, D. (Parasitology International, 2013)
Times Cited: 2 Kolarova, Libuse Skirnisson, Karl Ferte, Hubert Jouet, Damien 2
Keywords: Mergus serrator; Red-breasted merganser; Parasites

Feeding niche partitioning by three coexistent diving duck species in the same habitat during brood-rearing period - Kondrat'ev, A. V. (Zoologicheskii Zhurnal, 1992)
Breeding phenology, feeding contents, biotopical distribution, and feeding modes were studied in long-tailed duck. American black scoter, and great scaup with in the same lake. Long-tailed duck is more flexible in its habitat preference, and feeds mainly on plankton invertebrates. This species has the earliest hatching dates and the narrowest feeding spectrum. Block scoter and scaup have the largest niche overlap. Both these species feed on benthic invertebrates, but scoter prefers patches of a higher density. Scoter ducklings move slowly across the lake when foraging, dive to greater depth and stay under water longer than scaup ducklings. The latter species has the widest feeding spectrum, the shortest distance from the shore to the feeding place, the lowest diving intensity and higher swimming speed in comparison with scoter. Adaptive significance of different patterns of prey size and distribution is discussed.
Keywords: Behavior; Breeding Season; Clangula hyemalis; Long-tailed Duck; Trophic Interactions; Black Scoter; Melanitta nigra

Comparative Ecology of King Eider Somateria-Spectabilis and Spectacled Eider Somateria-Fischeri in Chaun Tundra - Kondrat'Ev, A. V.; Zadorina, L. V. (Zoologicheskii Zhurnal, 1992)
Biotopic distribution, feeding ecology and foraging behavior were studied in the area of sympatry. Over 100 nests of spectacled eider and 8 nests of king eider were found. 75% nests of the former were situated in gull colonies, and king eider nests were found separately along the coastal zone. No differences were registered in the feeding spectrum of both species from the same habitat, but the spectacled eiders used the wider habitat spectrum, which determines the wider feeding spectrum of the species. Feeding methods are similar both in ducklings and in adults. The birds fed mainly in shallow waters by head-dipping and up-ending. Diving as a feeding method is usual in non-breeding females and ducklings on deep lakes, and also for ducklings over two years old. Thus, the spectacled eider has a wider niche than the king eider.
Keywords: Behavior; Breeding Season; Somateria fischeri; Spectacled Eider; Abundance, Distribution, and Trends; King Eider; Somateria spectabilis; Trophic Interactions; Habitat

A COMPARATIVE ECOLOGY OF MELANITTA-AMERICANA, MELANITTA-DEGLANDI, AND CLANGULA-HYEMALIS IN THE ANADYR RIVER MIDDLE STREAM BASIN - Kondratyev, A. V. (ZOOLOGICHESKY ZHURNAL, 1989)
Times Cited in Web of Science Core Collection: 2 Total Times Cited: 3 Cited Reference Count: 17

Evaluation of harvest and information needs for North American sea ducks - Koneff, M. D.; Zimmerman, G. S.; Dwyer, C. P.; Fleming, K. K.; Padding, P. I.; Devers, P. K.; Johnson, F. A.; Runge, M. C.; Roberts, A. J. (PLOS ONE, 2017)
Wildlife managers routinely seek to establish sustainable limits of sport harvest or other regulated forms of take while confronted with considerable uncertainty. A growing body of ecological research focuses on methods to describe and account for uncertainty in management decision-making and to prioritize research and monitoring investments to reduce the most influential uncertainties. We used simulation methods incorporating measures of demographic uncertainty to evaluate risk of overharvest and prioritize information needs for North American sea ducks (Tribe Mergini). Sea ducks are popular game birds in North America, yet they are poorly monitored and their population dynamics are poorly understood relative to other North American waterfowl. There have been few attempts to assess the sustainability of harvest of North American sea ducks, and no formal harvest strategy exists in the U.S. or Canada to guide management. The popularity of sea duck hunting, extended hunting opportunity for some populations (i.e., special seasons and/or bag limits), and population declines have led to concern about potential overharvest. We used Monte Carlo simulation to contrast estimates of allowable harvest and observed harvest and assess risk of overharvest for 7 populations of North American sea ducks: the American subspecies of common eider (Somateria mollissima dresseri), eastern and western populations of black scoter (Melanitta americana) and surf scoter (M. perspicillata), and continental populations of white-winged scoter (M. fusca) and long-tailed duck (Clangula hyemalis). We combined information from empirical studies and the opinions of experts through formal elicitation to create probability distributions reflecting uncertainty in the individual demographic parameters used in this assessment. Estimates of maximum growth (rmax), and therefore of allowable harvest, were highly uncertain for all populations. Long-tailed duck and American common eider appeared to be at high risk of overharvest (i.e., observed harvest < allowable harvest in 5-7% and 19-26% of simulations, respectively depending on the functional form of density dependence), whereas the other populations appeared to be at moderate risk to low risk (observed harvest < allowable harvest in 22-68% of simulations, again conditional on the form of density dependence). We also evaluated the sensitivity of the difference between allowable and observed harvest estimates to uncertainty in individual demographic parameters to prioritize information needs. We found that uncertainty in overall fecundity had more influence on comparisons of allowable and observed harvest than adult survival or observed harvest for all species except long-tailed duck. Although adult survival was characterized by less uncertainty than individual components of fecundity, it was identified as a high priority information need given the sensitivity of growth rate and allowable harvest to this parameter. Uncertainty about population size was influential in the comparison of observed and allowable harvest for 5 of the 6 populations where it factored into the assessment. While this assessment highlights a high degree of uncertainty in allowable harvest, it provides a framework for integration of improved data from future research and monitoring. It could also serve as the basis for harvest strategy development as management objectives and regulatory alternatives are specified by the management community.
Times Cited in Web of Science Core Collection: 16 Total Times Cited: 16 Cited Reference Count: 71
Keywords: POPULATION; CONSERVATION; BRITISH-COLUMBIA; MANAGEMENT; AGE; JUDGMENTS; LESSONS; PACKAGE; RATIOS; UNCERTAINTY

Avian Cholera in Eider Ducks in Maine - Korschgen, C. E.; Gibbs, H. C.; Mendall, H. L. (Journal of Wildlife Diseases, 1978)
Outbreaks of avian cholera (Pasteurella multocida) occur frequently in common eiders (Somateria mollissima dresseri) in Maine [USA] during early summer. Studies over a 7 yr period show that over 90% of the loss occurred in incubating females and might be associated with their weakened condition because females do not feed during the incubation period. High nesting densities also may contribute to the losses. The exact source of P. multocida is unknown although carrier birds were found.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Disease

Studies of the Breeding Biology of the Red-Breasted Merganser Mergus-Serrator in Vejlerne North Jutland Denmark Vertebrate Predation - Kortegaard, L. (Dansk Ornitologisk Forenings Tidsskrift, 1968)
Keywords: Breeding Season; Mergus serrator; Red-breasted merganser

Some Features of Bird Behavior in Broods of Common Eider Somateria-Mollissima - Koryakin, A. S. (Vestnik Leningradskogo Universiteta Biologiya, 1982)
Interrelations between members of common elder broods at Kandalaksha Bay (White Sea) are described. In the first 3-4 days after hatching specific bonds are established between female and ducklings which are based on mutual individual recognition of calls. Communication between members of an eider brood is based on auditory signals. Main groups of ducklings' calls are comfort and discomfort calls. The high level of synchronization of ducklings' activities within the brood is an important adaptation to brooding period. This synchrony depends on the age of the young and their number in the brood. Brooding period duration in eider at Kandalaksha Bay is 45-60 and more days.
Keywords: Behavior; Breeding Season; Common Eider; Somateria mollissima

The Anthropogenic Disturbance Factor and Clutch Survival in the Eider Somateria-Mollissima L - Koryakin, A. S. (Zhurnal Obshchei Biologii, 1987)
A model quantitatively describing the consequences of the disturbance factor action on survival of clutches in common eider has been proposed on the basis of empirical data. The main causes of damage are the abandoning of nests and provoking of predation. The possibility of clutch loss because of disturbance is the less the longer is the duration of incubation and the lower is the level of predation in the region of nesting. The clutch loss depends on both individual features of birds behavior (caution with respect to man) and species specific features (described by three constants in the model). Analysis of the model and data on other regions of eider nesting area demonstrate that adaptation of individuals of protected species to the disturbance factor is more perspective strategy of protection than complete isolation of nesting places.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Productivity

Variations in size and shape of eggs of the velvet scoter, Melanitta fusca (L. ) - Koskimies, Jukka (Arch Soc Zool Bot Fennicae Vanamo", 1957)
This paper presents a statistical analysis of variation in size and shape of the eggs of the velvet scoter, Melanitta fusca, and a discussion of the causal relations and biological significance of these variations. The material consists of measurements of 82 clutches and 681 eggs from the years 1952-1955, including clutches of 2-4 successive years from 25 marked females. The variation was analyzed in relation to parentage, laying sequence, year, season, clutch size and age of the laying female. Different females consistently laid eggs of constant length, breadth and shape. This constancy was maintained over the entire 4-year period under review. The average breadth of the last eggs in the sequence (12 clutches analyzed) was significantly smaller than that of the other eggs. In spite of the long-term constancy of the individual egg dimensions, there is a significant tendency to minute parallel changes in egg breadth from year to year within the population studied. Possible correlations of size variations with laying season, clutch size and age of the female remain obscure. In the eggs of any 1 individual the variations in length and breadth are not correlated. In the female averages there is a significant positive correlation between length and breadth of the eggs. || ABSTRACT AUTHORS: Auth. summ
Keywords: Breeding Season; Melanitta fusca; White-winged Scoter; Physiology

Behavior and ecology of the young and of the brood-rearing females of the velvet scoter. II - Koskimies, Jukka (Ann Zool Soc Zool Bot Fennicae Vanamo", 1957)
The paper is based on observations in the outermost archipelago off the south coast of Finland in 194a-1957. The young broods tend to gather in sheltered shallow waters, their activity consisting of short alternating periods of feeding and rest. From the very first days of life, feeding is by bottom-diving. The young rest on land and are then primarily engaged in intensive grooming of plumage. Proximity of female to a group of young is necessary for normal preening to occur. The broods spend the night on shore, in cold weather the young ones mostly under the female. Family ties are very loose. In brood congregations resulting from inadequate numbers of suitable rearing areas in the archipelago, the imprinting of young to their mothers becomes disturbed, and the females cannot keep the broods apart. The females are aggressive towards one another and only one of them may stay with a combined brood. The young leave their own mother as a reaction to a female with stronger "mother-effect" and the latter remains entirely passive or even behaves aggressively. Giant broods resulting from a misreaction of the young have no positive biological value, are generally diffuse, and single young or small parentless groups of young often become separated from the family. Such young without social companions, are "nervously" active, abnormal in their feeding efforts, do not spend much time in care of plumage, and easily fall victim to predators (large gulls). Broodless females are gregarious and show slight interest in strange broods or single chicks, but appearance of predators increases their maternal behavior. Mortality of the young varied between 90 and 100 %, the principal factors being unfavorable weather, fluctuations in water temperature, and predation. The basic cause, however, is an inadequate adaptation to maritime conditions of the velvet scoter whose physiological and behavioral adaptations do not suit the conditions of the outer archipelago where it has settled only recently. The topography, extreme variations in water temperature, and predation by gulls are factors causing high brood mortality, and loose parent-young bonds further aggravate their effect. || ABSTRACT AUTHORS: Author
Keywords: Behavior; Breeding Season; Melanitta fusca; White-winged Scoter

Juvenile mortality and its causes in the velvet scoter, melanitta fusca - Koskimies, Jukka (Suomen Riista, 1958)
Summary of results of 1948-57 field studies, which were reported in more detail in papers listed in bibliography. Juvenile mortality in a closely controlled study area was 90-95%. Main direct factors were bad weather and fluctuations in water temperature, as well as predation. Basic reason for poor survival in the outer archipelago, however, is that this bird, originally an inhabitant of inland waters, is not adequately adapted to maritime conditions. || ABSTRACT AUTHORS: Courtesy Wildlife Rev. 94. 72. 1959
Keywords: Breeding Season; Melanitta fusca; White-winged Scoter; Survival

Dyeing young waterfowl for research purposes Finnish with English summ. - Koskimies, Jukka; Routamo, Eero (Suomen Riista, 1951)
The method proposed by Evans (1951) is described, together with experiences obtained in experiments in Finland in summer 1951. 54 young velvet scoters (Melanitta fusca) were dyed and a maximum additional egg mortality of 4% was observed. There was no noticeable difference in the behavior of dyed and undyed ducklings nor in the reactions of adult velvet scoters towards them. || ABSTRACT AUTHORS: Auth. summ
Keywords: Breeding Season; Melanitta fusca; White-winged Scoter; Techniques

Breeding biology of the velvet scoter (Melanitta f. fusca) - Koskimies, Jukka; Routamo, Eero (Riistatieteellisia Julkaisuja, 1953)
This study covers 1948-52, and deals with the period from arrival in spring to hatching of young. The velvet scoter breeds along the Fennoscandian coasts, favoring the more protected zones. During the study period pairs increased from 0.5 to 1.3 per/ha. land area. Birds arrived on nesting grounds early in May, pairing already having occurred during migration. A typical nest lies between small rocks in bushes of Juniper under or between branched stems. Data from 23 banded females indicate that they return to the same islet each year. Average egg laying frequency was one egg per 40 hrs., and laying usually occurred in the early morning. Clutch size varied from 5 to 10, most commonly 8 to 10, and averaged 8.45. Clutches started earliest were largest, and decreased in size with progressive date of 1st egg. Red-breasted mergansers commonly dropped eggs in scoter nests, but they did not hatch. Incubation period varied from 26 to 29 days and averaged 27.5 days. Hatching in 70% of the cases occurred between July 8-14. Of 328 eggs, 8.1% remained unhatched. || ABSTRACT AUTHORS: W. Swank
Keywords: Breeding Season; Melanitta fusca; White-winged Scoter; Productivity; Habitat

Comparison of bivalve communities between moulting and wintering areas used by Common Scoter Melanitta nigra in the German North Sea - Kottsieper, J.; Schuckel, U.; Schwemmer, P.; Fox, A. D.; Garthe, S. (ESTUARINE COASTAL AND SHELF SCIENCE, 2019)
The Common Scoter (Melanitta nigra) is a common sea duck, which predominantly feeds on sedentary benthic bivalve prey and occurs in large late-summer moulting concentrations in the German North Sea in areas which differ from those used by later wintering concentrations. Assuming scoters distribute in response to prey accessibility, abundance and profitability, we hypothesis that their contrasting distribution during moult compared to winter potentially reflects differences in prey type and distribution. We compared benthic bivalve community composition, abundance, ash-free dry mass and flesh-to-shell ratios between both areas to investigate factors influencing the seasonal difference in areas used by scoters. The American Razor Clam (Ensis leet) was the most common bivalve in the moulting area (mean abundance 1004 +/- 1681 Ind. m(-2), mean SD) with the highest flesh-to-shell ratio (0.341 gm(-2) +/- 0.729 gm(-2)), whereas the American Piddock (Petricolaria pholadiformis) showed the highest ash-free dry mass (0.635 gm(-2) +/- 0.392 gm(-2)). In the wintering area, the most common bivalve was the Bean-like Tellin (Fabulina fabula, 13 +/- 17 ind. m(-2)), Spisula solida had the highest ashfree dry mass (1.639 gm(-2) +/- 1.262 gm(-2)) and F. fabula and Abra alba had the highest flesh-to-shell ratios. Overall benthic species community composition differed considerably between moulting and wintering areas, with fewer species and lower abundances in the wintering area. The high abundance and food quality (flesh-to-shell ratio) of E. leei (an invasive alien to the German North Sea since the 1980s) in the moulting area suggests its relative importance and potentially explains the seasonal differences of Common Scoter distributions.
Times Cited in Web of Science Core Collection: 6 Total Times Cited: 6 Cited Reference Count: 46
Keywords: Marine birds; TEMPERATURE; VARIABILITY; WADDEN SEA; SPECIES DISTRIBUTION; Benthos; Environmental factors; MACOMA-BALTHICA; MACROFAUNA; Marine ecology; Seaduck diet

An invasive alien bivalve apparently provides a novel food source for moulting and wintering benthic feeding sea ducks - Kottsieper, J.; Schwemmer, P.; Markones, N.; Fox, A. D.; Garthe, S. (HELGOLAND MARINE RESEARCH, 2019)
Since its introduction from North America in the 1970s, the American razor clam Ensis leei (M. Huber, 2015) has successfully spread throughout North Sea coasts from Spain to Norway and the United Kingdom to the western Baltic. We investigated the distribution and abundance of this non-indigenous bivalve species as a potential novel food resource for common scoter Melanitta nigra (Linnaeus, 1758) along the eastern German North Sea coast. Highest densities of flightless moulting and wintering common scoters coincided with areas of high E. leei abundance. Other European studies showed common scoters extensively feed on E. leei. Even with these findings, it remains difficult to demonstrate convincingly that E. leei constitutes a major food source for common scoter in the German North Sea during their non-breeding season. However, our study suggests that E. leei has become an important prey item for internationally important concentrations of common scoters at large spatial scales.
Times Cited in Web of Science Core Collection: 3 Total Times Cited: 3 Cited Reference Count: 30
Keywords: Melanitta nigra; Common scoter; American razor clam; Ensis leei; ENSIS-DIRECTUS; German Bight; Subtidal benthos

THE NUMBERS AND SEASONAL DISTRIBUTION OF THE WESTERN POPULATION OF THE KING EIDER (SOMATERIA SPECTABILIS): MONITORING ORGANIZATION IN THE NORTHERN SEAS OF RUSSIA - Krasnov, Y. V.; Ezhov, A. V.; Galaktionov, K. V.; Shavykin, A. A. (ZOOLOGICHESKY ZHURNAL, 2020)
Our own observations and relevant reports in the literature concerning the western population of the King Eider, Somateria spectabilis in the Barents, White and Kara seas are summarized/ We use schematic maps to show the areas where the birds gather together in the wintering and moulting periods and provide data on bird counts, age and sex in the Russian part of the distribution range. Six to ten thousand birds were wintering on the White Sea and in the southern part of the Barents Sea in 1994-2009. In the winter of 2009, males were obviously predominant (70.2%); immature individuals accounted for 2.6%. During moulting, the highest concentrations of king eiders were registered in the southeastern part of the Barents Sea: the total bird count in this area was 18 to 20 thousand individuals. We estimated the total of the king eiders in the Barents Sea region population as 80 to 110 thousand individuals, discarding the birds that winter near the coasts of Novaya Zemlya. We demonstrate which factors influence the distribution of birds during particular seasons and their movements within the range. To further advance king eider monitoring, we suggest suitable parts of water areas and adequate approaches to bird counting.
Times Cited in Web of Science Core Collection: 0 Total Times Cited: 0 Cited Reference Count: 45
Keywords: king eider; PECHORA SEA; BARENTS; MIGRATION PATTERNS; MOLTING LOCATIONS; moulting; numbers; population; the Barents Sea; the Kara Sea; the White Sea; WATERFOWL; wintering

Numbers and Seasonal Distribution of the Western Population of the King Eider (Somateria spectabilis): Monitoring Organization in the Northern Seas of Russia - Krasnov, Y. V.; Ezhov, A. V.; Galaktionov, K. V.; Shavykin, A. A. (BIOLOGY BULLETIN, 2021)
The molting and wintering areas of the western King eider population (Somateria spectabilis) in the Barents, White, and Kara seas are described based on our own observations and relevant reports in the literature; schematic maps show bird gathering areas in these periods. The data on counts of wintering and molting birds, their age, and sex composition in the Russian part of the distribution range are provided. Six to ten thousand birds of this species wintered on the White Sea and in the southern part of the Barents Sea in 1994-2009. In the winter of 2009, males were obviously predominant (70.2%); immature individuals accounted for 2.6%. The highest concentrations of King eiders were recorded in the southeastern part of the Barents Sea during molting. The total number of molting King eiders in this area was 18 000 to 20 000 individuals. We estimated the total size of the western King eider population in the Barents Sea region. Discarding the birds that winter near the coasts of Novaya Zemlya, this indicator may range from 80 000 to 110 000 individuals. Factors that influence the distribution of birds during particular seasons and their movements within the range are shown. To further advance King eider monitoring, we suggest suitable parts of water areas and adequate approaches to bird counting.
Times Cited in Web of Science Core Collection: 0 Total Times Cited: 0 Cited Reference Count: 45
Keywords: King eider; MIGRATION PATTERNS; MOLTING LOCATIONS; numbers; population; the Barents Sea; the Kara Sea; the White Sea; WATERFOWL; wintering; BARENTS SEA; molting

STATUS, NUMBER AND MONITORING OF THE COMMON EIDER (SOMATERIA MOLLISSIMA) POPULATION IN THE BARENTS AND WHITE SEAS - Krasnov, Y. V.; Gavrilo, M. V.; Shavykin, A. A. (Zoologichesky Zhurnal, 2015)
Breeding, moulting and wintering ranges of the common eider (Somateria mollissima) were mapped and described in the southern part of the Barents Sea region, including the White Sea population in the western White Sea and the Murmansk population in the northwestern White Sea and the southeastern Barents Sea. The current number was determined for both populations: it was the highest in the 2000s for the entire period of ornithological survey in the region since the 1950s. The only reliable method for determining the total population number was shown to be aerial survey from a helicopter. The best season for studying the White Sea population is March - early April (wintering); the most favourable period for investigating the Murmansk population is August (postbreeding/moulting). The population status of common eiders in the northern and eastern parts of the Barents Sea has not been defined yet. On the Franz-Josef Land, common eider is distributed sporadically, and its number was assessed using expert estimates. The current number of eider on the Novaya Zemlya is unknown. The helicopter-based aerial survey in late summer during postbreeding season is the only relevant method to obtain reliable estimates for the population of common eiders inhabiting the Franz-Josef Land and Novaya Zemlya.
Krasnov, Yu. V. Gavrilo, M. V. Shavykin, A. A.
Keywords: Common Eider; Somateria mollissima; Abundance, Distribution, & Trends

Status, Number, and Monitoring of the Common Eider (Somateria mollissima) Population in the Barents Sea and the White Sea - Krasnov, Y. V.; Gavrilo, M. V.; Shavykin, A. A. (BIOLOGY BULLETIN, 2016)
The breeding, molting, and wintering ranges of the common eider (Somateria mollissima) were mapped and described in the southern part of the Barents Sea region, including the White Sea population in the western White Sea and the Murmansk population in the northwestern White Sea and the southeastern Barents Sea. The present-day abundance was determined for both populations: since the 1950s, it was the highest in the 2000s for the entire period of ornithological monitoring in the region. Aerial survey from a helicopter is considered to be the only reliable method for estimation of the total population number. The best season for surveying the White Sea population is March-early April (wintering); the most favorable period for surveying the Murmansk population is August (postbreeding/molting). The population status of the common eider in the northern and eastern parts of the Barents Sea has not yet been evaluated. On Franz-Josef Land, the common eider is distributed sporadically, and its number was assessed using expert estimates. The current abundance of the common eider on Novaya Zemlya is unknown. Helicopter-based aerial survey performed in late summer during the postbreeding season is the only relevant method to obtain reliable estimates for the population of the common eider inhabiting Franz-Josef Land and Novaya Zemlya.
Times Cited in Web of Science Core Collection: 1 Total Times Cited: 1 Cited Reference Count: 29
Keywords: common eider; population; the Barents Sea; the White Sea; monitoring

Sex-Age Structure of the White Sea Endemic Population of Common Eiders Somateria mollisima - Krasnov, Yu V.; Gavrilo, M. V.; Shavykin, A. A.; Vashchenko, P. S. (Doklady Akademii Nauk, 2010)
Keywords: Common Eider; Somateria mollissima

Character and Peculiarities of Feeding of Common Eider (Somateria mollissima) in White Sea - Krasnov, Yu V.; Shklyarevitch, G. A.; Goryaev, Yu I. (Doklady Akademii Nauk, 2009)
Keywords: Common Eider; Somateria mollissima; Trophic Interactions

Population dynamics of white-winged scoters - Krementz, David G.; Brown, Patrick W.; Kehoe, F. Patrick; Houston, C. Stuart (Journal of Wildlife Management, 1997)
A significant (P lt 0.01) decline between 1961 and 1993 in ratio of harvested young per adult in the Atlantic Flyway (age ratio) of white-winged scoters (Melanitta fusca) led us to examine annual survival rates and harvest of this species. Compared to waterfowl with similar life histories, black scoters (M. nigra) and surf scoters (M. perspicillata), the decline in age ratios of white-winged scoter age ratios was not significantly different (P = 0.11). Adult females banded at Redberry Lake, Saskatchewan that winter along both coasts, had high annual survival rates (0.773 +- 0.0176 (SE)). High harvest in the Atlantic Flyway was not followed by an increase in production (age ratios) the following year or 2, i.e., there was no short-term rebound in recruitment by the population. Harvest of white-winged scoters in the Atlantic Flyway was explained by the age ratio in the fall flight and by hunter effort.
Keywords: Breeding Season; Melanitta fusca; Nonbreeding Seasons; White-winged Scoter; Productivity; Population Dynamics; Survival

Effects of down collection on incubation temperature, nesting behaviour and hatching success of common eiders (Somateria mollissima) in west Iceland - Kristjansson, T. O.; Jonsson, J. E. (Polar Biology, 2011)
Times Cited: 3 Kristjansson, Thordur Orn Jonsson, Jon Einar 3
Keywords: Conservation; common eider; Breeding Season; Productivity; somateria mollissima

Cooperative incubation behaviour in a super dense Common Eider Somateria mollissima colony - Kristjansson, T. O.; Jonsson, J. E. (Bird Study, 2015)
Capsule Common Eiders at Rif in west Iceland commonly show joint nest attendance, which may be an exaggerated behavioural response to the visual stimulus of many nests so close to their own nest. This represents a new insight into incubation behaviour in colonies with extremely high nest densities.
Kristjansson, Thordur Orn Jonsson, Jon Einar
Keywords: Behavior; Breeding Season; Common Eider; Somateria mollissima

Spring diet of common eiders (Somateria mollissima) in BreiA degrees afjorA degrees ur, West Iceland, indicates non-bivalve preferences - Kristjansson, T. O.; Jonsson, J. E.; Svavarsson, J. (Polar Biology, 2013)
Times Cited: 1 Kristjansson, Thordur Orn Jonsson, Jon Einar Svavarsson, Jorundur 1
Keywords: Nonbreeding Seasons; Somateria mollissima; Trophic Interactions; Common eider

Variation in nest composition and abundances of ectoparasites between nests in colonially breeding Common Eiders Somateria mollissima - Kristjansson, T. O.; Jonsson, J. E.; Svavarsson, J. (Bird Study, 2016)
Capsule: The occurrence of high numbers of ectoparasites in nests of Common Eiders may be related to nest densities and nesting behaviour.Aims: To estimate abundances of ectoparasites and occurrence of blood-covered eggs, and relate those to nest bowl ages, nest bottom material and the incubation stages of eggs, in nests at two different Common Eider colonies.Methods: Nests were collected at Hvallatur and Rif, two sites at Breioafjorour, West Iceland, in June and July 2012. The nest bottom material was classified to vegetation species and invertebrates were identified to species when possible.Results: The flea Ceratophyllus garei was the dominant ectoparasite at both sites, with median abundances higher at Hvallatur than at Rif in June. In July, the mean abundance of fleas was higher than observed in June at Rif. There were positive relationships between the flea abundances and the incubation stages of the nests, the blood cover of the eggs and the type of nesting material. No relationship was observed between the age of nesting bowls and adult flea abundances.Conclusion: Disadvantages of large parasite loads on the later nesters (second clutch in each nest) at Rif may be compensated by shared nest attendance and the concurrent added time for preening for females while other females attend their nests.
Kristjansson, Thordur Orn Jonsson, Jon Einar Svavarsson, Jorundur
Keywords: Behavior; Breeding Season; Common Eider; Somateria mollissima; Parasites

Validation of a Habitat Suitability Model for Eider Nesting Islands - Krohn, W. B.; Owen, R. B. Jr (Transactions of the Northeast Section of the Wildlife Society, 1988)
Blumton et al. (1988) developed a Habitat Suitability Index (HSI) model designed to rank common eider (Somateria mollissima) nesting islands according to total number of nests. We collected disturbance and vegetation data for 34 coastal Maine [USA] islands to test the model's performance against (1) total nests per island, and (2) nests per vegetated hectare. Ranking of the model's output was significantly correlated with rankings of the two test criteria (P < 0.001), and model output was significantly correlated with both test criteria (P < 0.05). We recommend using the model to rank nesting islands or to determine good (.gtoreq. 10 nests) from poor (< 10 nests) islands. Because model precision was poor, we would not use the HSI model to predict numbers of nests on individual islands. The model is a first approximation of the relationship between common eiders and their nesting habitat.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Habitat

Streptocara formosensis Sugimoto, 1930 (Nematoda: Acuariidae) in wild ducks from the southern coast of the Baltic Sea - Krolaczyk, K.; Kavetska, K. M.; Stapf, A.; Kalisinska, E. (Helminthologia, 2012)
Times Cited: 1 Krolaczyk, K. Kavetska, K. M. Stapf, A. Kalisinska, E. Kavetska, Katarzyna /K-4001-2012 1
Keywords: Nonbreeding Seasons; Sea Ducks; Parasites

Remarkable Concentration of Velvet Scoters Melanitta-Fusca L. In Northern Upper Lusatia East Germany - Krueger, S.; Richter, J. (Beitraege zur Vogelkunde, 1987)
Keywords: Abundance, Distribution, and Trends; Melanitta fusca; White-winged Scoter

The occurrence of selected seabirds and coastal birds off Wangerooge in autumn: The influence of wind direction and wind force. - Krueger, Thorsten; Garthe, Stefan (Journal fuer Ornithologie, 2002)
Between 1995 and 1999 a study was made of the autumn migration of seabirds and coastal birds on the seaward side of Wangerooge Island (SE German Bight, East Frisian Islands; 53degree47'N 07degree54'E). Analyses are based on a total of 418 h on 118 days from 1 September to 15 November. Migration patterns in relation to wind direction and wind force are presented for 19 species. The patterns differed significantly from a hypothetical distribution. It proved possible to allocate the observed species to one of two groups, based on their occurrence patterns: 1. Those which migrated regularly and were wont to occur whatever the wind direction and wind force: divers, grebes, Great Cormorant, Common Shelduck, Barnacle Goose, Brent Goose, Great Scaup, Black Scoter, Common Eider, Sandwich Tern, Common/Arctic Tern, Little Gull, Common Guillemot and Razorbill. In general, their migration intensity is strongest during weak tailwinds (easterly winds) and during strong on-shore winds from W/NW. Plainly, the latter case is not due to actual increase in migration intensity but is rather the result of birds being pushed closer to the coast while migrating farther out at sea. 2. Seabirds such as Northern Fulmar, Leach's Petrel, Sooty Shearwater, Northern Gannet and skuas occur chiefly or exclusively during gale-force winds from W or NW (weather system after passage of cyclones). The reasons for the observed patterns are discussed.
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons; Migration

Spatial and temporal variations in the population structure of the soft-shell clam Mya arenaria in the Pomeranian Bay (Southern Baltic Sea) - Kube, Jan (Journal of Sea Research, 1996)
The population structure of Mya arenaria has been investigated in the sublittoral zone of the Pomeranian Bay (southern Baltic Sea). Box-corer samples were collected during a 1.5-year period in 1993/94 to follow changes in size and age structure of the clam populations in different parts of the study area. Large spatial differences in population structure were found between the sheltered southwest of the Bay and the shallow and exposed Oder Bank in the centre. The stock of the Oder Bank consisted of two different clam types. A slow-growing cohort was assumed to be autochtonous on the Oder Bank, whereas a fast-growing one was assumed to have immigrated from the surrounding area. The contribution of the two cohorts to the total density varied seasonally. Because of bedload transport of clams, the contribution to the reduction of the clam stock by wintering sea ducks could not be quantified. In the southwest of the Pomeranian Bay erosion was of minor importance. High mortality rates during the first two years of life were assumed to be caused by predation. Mortality rates of older cohorts remained stable until old age. Variations in cohort strength were related to interannual differences in the reproductive success. A mild winter presumably lowers the reproductive success in the subsequent summer. Severe oxygen depletion in summer 1994 caused a strong reduction in the clam stock at stations deeper than 10 m.
Keywords: Sea Ducks - General; Nonbreeding Seasons; Trophic Interactions

The Peculiarities of Parasiting of Polymorphus phippsi (Palaeacanthocephala: Polymorphidae) in the Intestines of Seabirds from the Barents Sea - Kuklina, M. M.; Kuklin, V. V. (BIOLOGY BULLETIN, 2021)
Aspects of the localization and digestion physiology of the acanthocephalan Polymorphus phippsi (Kostylew, 1922) (Palaeacanthocephala: Polymorphidae) from the intestines of seabirds (common eider Somateria mollissima (Linnaeus, 1758), king eider Somateria spectabilis (Linnaeus, 1758), and herring gull Larus argentatus (Pontoppidan, 1763)) from various regions of the Barents Sea, as well as its relationships with the final hosts, have been studied. It has been revealed that P. phippsi parasitizes in the distal section of the small intestine of birds. The infestation intensity of P. phippsi is 82 +/- 35.2 (5-282) individuals for common eider, 31.5 +/- 18.9 (1-115) for king eider, and 2.4 +/- 0.4 (1-4) individuals for herring gull chicks. Membrane digestion processes involving proteases and glycosidases have been recorded on the surface of the tegument of P. phippsi. It is shown that the protease activity increases at attachment sites of the parasite in the intestinal mucosa of birds and the intensity of processes of cavity and membrane digestion involving proteases and glycosidases increases.
Times Cited in Web of Science Core Collection: 0 Total Times Cited: 0 Cited Reference Count: 32
Keywords: EIDERS; seabirds; ACANTHOCEPHALA; acanthocephalans; digestion; glycosidases; proteases

Drivers of decline and changed nest-site preference of the Baltic eider: an island-level analysis from south-western Finland - Kurvinen, L.; Kilpi, M.; Nordstrom, M.; Ost, M. (Ornis Fennica, 2016)
The recent large-scale decline of Eiders (Somateria mollissima) in the Baltic Sea is well documented by long-term population monitoring. One hypothesis to explain the decline is increased predation pressure during breeding, but because the decline has been steep and geographically broad, multiple drivers may be involved. Here we explore whether some of these hitherto unidentified drivers relate to the breeding habitat. To this end, we performed an analysis of long-term monitoring data from ca. 300 islands from the Archipelago Sea, SW Finland, representing five geographical sub-areas, during 1993-2012. We analysed population trends and whether nest-site preference changed over time. The results showed steep population declines in the sub-areas farthest from the mainland and a more moderate decline in the sub-area closest to the mainland. The presence of breeding gulls (Larus spp.) on the Eider breeding island had a consistently positive effect on Eider breeding numbers throughout the study period. In contrast, the presence of breeding White-tailed Sea Eagles (Haliaeetus albicilla) had a negative effect on breeding numbers, but only during the early study period when the Eagle breeding population was still small. Interestingly, the sign of the effect of the distance from the nearest neighbouring island on Eider breeding numbers changed over time. Eider breeding numbers positively correlated with island size and distance to neighbouring islands in the early period, whereas exposed large islands with islands nearby were positively associated with Eider breeding abundance during the late period. Future conservation efforts should shift from site-specific conservation to population-specific management due to the shift in nest-site preference. Furthermore, the positive influence of gulls warrants the adoption of conservation measures taking interspecific interactions into consideration.
Kurvinen, Lasse Kilpi, Mikael Nordstrom, Mikael Ost, Markus
Keywords: Conservation; Breeding Season; Common Eider; Somateria mollissima; Habitat; Abundance, Distribution, & Trends

Mercury Isotope Study of Sources and Exposure Pathways of Methylmercury in Estuarine Food Webs in the Northeastern US - Kwon, S. Y.; Blum, J. D.; Chen, C. Y.; Meattey, D. E.; Mason, R. P. (Environmental Science & Technology, 2014)
We measured mercury (Hg) isotope ratios in sediments and various estuarine organisms (green crab, blue mussel, killifish, eider) to investigate methylmercury (MMHg) sources and exposure pathways in five Northeast coast (U.S.) estuaries. The mass independent Hg isotopic compositions (MIF; Delta Hg-199) of the sediments were linearly correlated with the sediment 1/Hg concentrations (Delta Hg-199: r(2) = 0.77, p < 0.05), but the mass dependent isotope compositions (MDF; delta Hg-202) were not (r(2) = 0.26, p = 0.16), reflecting inputs of anthropogenic Hg sources with varying delta Hg-202. The estuarine organisms all display positive Delta Hg-199 values (0.21 to 0.98 parts per thousand) indicating that MMHg is photodegraded to varying degrees (5-12%) prior to entry into the food web. The delta Hg-202 and Delta Hg-199 values of most organisms can be explained by a mixture of MMHg and inorganic Hg from sediments. At one contaminated site mussels have anomalously high delta Hg-202, indicating exposure to a second pool of MMHg, compared to sediment, crabs and fish. Eiders have similar Delta Hg-199 as killifish but much higher delta Hg-202, suggesting that there is an internal fractionation of delta Hg-202 in birds. Our study shows that Hg isotopes can be used to identify multiple anthropogenic inorganic Hg and MMHg sources and determine the degree of photodegradation of MMHg in estuarine food webs.
Kwon, Sae Yun Blum, Joel D. Chen, Celia Y. Meattey, Dustin E. Mason, Robert P.
Keywords: Common Eider; Contaminants; Somateria mollissima

Persistent organic pollutants in biota samples collected during the Ymer-80 expedition to the Arctic - Kylin, H.; Hammar, J.; Mowrer, J.; Bouwman, H.; Edelstam, C.; Olsson, M.; Jensen, S. (Polar Research, 2015)
During the 1980 expedition to the Arctic with the icebreaker Ymer, a number of vertebrate species were sampled for determination of persistent organic pollutants. Samples of Arctic char (Salvelinus alpinus, n = 34), glaucous gull (Larus hyperboreus, n = 8), common eider (Somateria mollissima, n = 10), Brunnich's guillemot (Uria lomvia, n = 9), ringed seal (Pusa hispida, n = 2) and polar bear (Ursus maritimus, n = 2) were collected. With the exception of Brunnich's guillemot, there was a marked contamination difference of birds from western as compared to eastern/northern Svalbard. Samples in the west contained a larger number of polychlorinated biphenyl (PCB) congeners and also polychlorinated terphenyls, indicating local sources. Brunnich's guillemots had similar pollutant concentrations in the west and east/north; possibly younger birds were sampled in the west. In Arctic char, pollutant profiles from lake Linnevatn (n = 5), the lake closest to the main economic activities in Svalbard, were similar to profiles in Arctic char from the Shetland Islands (n = 5), but differed from lakes to the north and east in Svalbard (n = 30). Arctic char samples had higher concentrations of hexachlorocyclohexanes (HCHs) than the marine species of birds and mammals, possibly due to accumulation via snowmelt. Compared to the Baltic Sea, comparable species collected in Svalbard had lower concentrations of PCB and dichlorodiphenyltrichloroethane (DDT), but similar concentrations indicating long-range transport of hexachlorobenzene, HCHs and cyclodiene pesticides. In samples collected in Svalbard in 1971, the concentrations of PCB and DDT in Brunnich's guillemot (n = 7), glaucous gull (n = 2) and polar bear (n = 2) were similar to the concentrations found in 1980.
Kylin, Henrik Hammar, Johan Mowrer, Jacques Bouwman, Henk Edelstam, Carl Olsson, Mats Jensen, Soeren
Keywords: Common Eider; Contaminants; Somateria mollissima

Chemical contaminants in the Wadden Sea: Sources, transport, fate and effects - Laane, Rwpm; Vethaak, A. D.; Gandrass, J.; Vorkamp, K.; Kohler, A.; Larsen, M. M.; Strand, J. (Journal of Sea Research, 2013)
Times Cited: 1 Laane, R. W. P. M. Vethaak, A. D. Gandrass, J. Vorkamp, K. Koehler, A. Larsen, M. M. Strand, J. Vethaak, Andre/N-6562-2013; Strand, Jakob/H-4181-2011 Strand, Jakob/0000-0001-5756-9546 1
Keywords: Nonbreeding Seasons; Contaminants; Somateria mollissima; Common eider

Surf Scoters Melanitta perspicillata aggregate in association with ephemerally abundant polychaetes - Lacroix, Deborah Lise; Boyd, Sean; Esler, Dan; Kirk, Molly; Lewis, Tyler; Lipovsky, Sandy (Marine Ornithology, 2005)
Keywords: Abundance, Distribution, and Trends; Nonbreeding Seasons; Melanitta perspicillata; Surf Scoter; Trophic Interactions

Effect of underwater seismic surveys on molting male Long-tailed Ducks in the Beaufort Sea, Alaska - Lacroix, Deborah L.; Lanctot, Richard B.; Reed, John A.; McDonald, Trent L. (Canadian Journal of Zoology, 2003)
Large numbers of Long-tailed Ducks (Clangula hyemalis) (10 000-30 000) undergo a postnuptial wing molt along barrier islands of the Beaufort Sea, Alaska. To investigate the potential effects of underwater seismic activities on this species, we monitored the number and diving behavior of molting Long-tailed Ducks before, during, and after seismic activities in a seismic area and two control areas nearby between July and September 2001. Aerial surveys documented a decline in duck numbers in both seismic and control areas during the period of seismic activity. We used automated data-collection computers to monitor the presence and diving behavior of radio-equipped Long-tailed Ducks residing within 2.5 km of a series of computer setups located along the barrier islands and on the mainland. A statistical analysis based on a modified before-after control-impact approach found no difference in indices of site fidelity or diving intensity between the seismic area and two control areas. Thus, we found no effect of seismic activity on movements and diving behavior of molting Long-tailed Ducks. These results should be evaluated carefully, however, as logistical and ecological factors limited our ability to detect more subtle disturbance effects. We recommend additional studies on other bird species to fully understand the effects of underwater seismic testing.
Keywords: Conservation; Behavior; Abundance, Distribution, and Trends; Nonbreeding Seasons; Molt; Clangula hyemalis; Long-tailed Duck

Observations of above-surface littoral foraging in two sea ducks, Barrow's Goldeneye, Bucephala islandica, and Surf Scoter, Melanitta perspicillata, in coastal southwestern British Columbia - Lacroix, Deborah L.; Wright, Kenneth G.; Kent, Daniel (Canadian Field-Naturalist, 2004)
Barrow's Goldeneyes (Bucephala islandica) and Surf Scorers (Melanitta perspicillata) were observed on four separate occasions, by three different observers, foraging on Bay Mussels (Mytilus trossulus) above the water surface. This unique foraging behaviour could be attributed to diurnal spring tides and reduced lower intertidal mussel abundance.
Keywords: Behavior; Nonbreeding Seasons; Melanitta perspicillata; Surf Scoter; Trophic Interactions; Barrow's Goldeneye; Bucephala islandica

Lead concentrations in blood from incubating common eiders (Somateria mollissima) in the Baltic Sea - Lam, S. S.; McPartland, M.; Noori, B.; Garbus, S. E.; Lierhagen, S.; Lyngs, P.; Dietz, R.; Therkildsen, O. R.; Christensen, T. K.; Tjornlov, R. S.; Kanstrup, N.; Fox, A. D.; et al. (ENVIRONMENT INTERNATIONAL, 2020)
Here we investigate if lead may be a contributing factor to the observed population decline in a Baltic colony of incubating eiders (Somateria mollissima). Body mass and blood samples were obtained from 50 incubating female eiders at the Baltic breeding colony on Christianso during spring 2017 (n = 27) and 2018 (n = 23). All the females were sampled twice during early (day 4) and late (day 24) incubation. The full blood was analysed for lead to investigate if the concentrations exceeded toxic thresholds or changed over the incubation period due to remobilisation from bones and liver tissue. Body mass, hatch date and number of chicks were also analysed with respect to lead concentrations. The body mass (mean +/- SD g) increased significantly in the order: day 24 in 2018 (1561 +/- 154 g) < day 24 in 2017 (1618 +/- 156 g) < day 4 in 2018 (2183 +/- 140 g) < day 4 in 2017 (2359 +/- 167 g) (all p < 0.001). The lead concentrations increased significantly in the opposite order i.e. day 4 in 2017 (41.7 +/- 67.1 mu g/L) < day 24 in 2017 (55.4 +/- 66.8 mu g/L) < day 4 in 2018 (177 +/- 196 mu g/L) < day 24 in 2018 (258 +/- 243) (all p < 0.001). From day 4 to 24, the eider females had a 1.33-fold increase in blood lead concentrations in 2017 and a 1.46-fold increase in 2018. Three of the birds (13%) sampled in 2018 had lead concentrations that exceeded concentrations of clinical poisoning (500 mu g/L) and eleven (48%) had concentrations that exceeded the threshold for subclinical poisoning (200 mu g/L). In 2017, none of the birds exceeded the high toxic threshold of clinical poisoning while only one (4%) exceeded the lower threshold for subclinical poisoning. Three of the birds (6%) sampled in 2018 had lead concentrations that exceeded those of clinical poisoning while 12 birds (24%) resampled in both years exceeded the threshold for subclinical poisoning. In addition, lead concentrations and body mass on day 4 affected hatch date positively in 2018 (both p < 0.03) but not in 2017. These results show that bioavailable lead in bone and liver tissue pose a threat to the health of about 25% of the incubating eiders sampled. This is particularly critical because eiders are largely capital breeding which means that incubating eiders are in an energetically stressed state. The origin of lead in incubating eiders in the Christianso colony is unknown and it remains an urgent priority to establish the source, prevalence and mechanism for uptake. The increase in lead from day 4 to day 24 is due to bone and liver remobilization; however, the additional lead source(s) on the breeding grounds needs to be identified. Continued investigations should determine the origin, uptake mechanisms and degree of exposure to lead for individual birds. Such research should include necropsies, x-ray, lead isotope and stable C and N isotope analyses to find the lead sources(s) in the course of the annual cycle and how it may affect the population dynamics of the Christianso colony which reflects the ecology of the Baltic eiders being suitable for biomonitoring the overall flyway.
Times Cited in Web of Science Core Collection: 8 Total Times Cited: 10 Cited Reference Count: 58
Keywords: BIRDS; TRACE-ELEMENTS; EXPOSURE; MORTALITY EVENT; Starvation; Avian; AMMUNITION; Emaciation; Food depletion; Parasite infection; PB; SPECTACLED EIDERS; Waterfowl

Seroprevalence of avian influenza in Baltic common eiders (Somateria mollissima) and pink-footed geese (Anser brachyrhynchus) - Lam, S. S.; Tjornlov, R. S.; Therkildsen, O. R.; Christensen, T. K.; Madsen, J.; Daugaard-Petersen, T.; Ortiz, J. M. C.; Peng, W. X.; Charbonneaux, M.; Rivas, E. I.; Garbus, S. E.; Lyngs, P.; et al. (ENVIRONMENT INTERNATIONAL, 2020)
Blood plasma was collected during 2016-2018 from healthy incubating eiders (Somateria molissima, n = 183) in three Danish colonies, and healthy migrating pink-footed geese (Anser brachyrhynchus, n = 427) at their spring roost in Central Norway (Svalbard breeding population) and their novel flyway through the Finnish Baltic Sea (Russian breeding population). These species and flyways altogether represent terrestrial, brackish and marine ecosystems spanning from the Western to the Eastern and Northern part of the Baltic Sea. Plasma of these species was analysed for seroprevalence of specific avian influenza A (AI) antibodies to obtain information on circulating AI serotypes and exposure. Overall, antibody prevalence was 55% for the eiders and 47% for the pink-footed geese. Of AI-antibody seropositive birds, 12% (22/183) of the eiders and 3% (12/427) of the pink-footed geese had been exposed to AI of the potentially zoonotic serotypes H5 and/or H7 virus. AI seropositive samples selected at random (n = 33) showed a low frequency of serotypes H1, H6 and H9. Future projects should aim at sampling and isolating AI virus to characterize dominant serotypes and virus strains (PCR). This will increase our understanding of how AI exposure may affect health, breeding and population viability of Baltic common eiders and pink-footed geese as well as the potential spill-over to humans (zoonotic potential).
Times Cited in Web of Science Core Collection: 4 Total Times Cited: 4 Cited Reference Count: 54
Keywords: BIRDS; PREVALENCE; Health; MORTALITY EVENT; PATHOLOGY; Waterfowl; Avian Influenza; BRANTA-CANADENSIS; CANADA GEESE; EPIDEMIOLOGY; Fitness; INFECTIONS; Reproduction; VIRUSES

Annual-Cycle Movements and Phenology of Black Scoters in Eastern North America - Lamb, J. S.; Gilliland, S. G.; Savard, J. P. L.; Loring, P. H.; McWilliams, S. R.; Olsen, G. H.; Osenkowski, J. E.; Paton, P. W. C.; Perry, M. C.; Bowman, T. D. (JOURNAL OF WILDLIFE MANAGEMENT, 2021)
Sea ducks exhibit complex movement patterns throughout their annual cycle; most species use distinct molting and staging sites during migration and disjunct breeding and wintering sites. Although research on black scoters (Melanitta americana) has investigated movements and habitat selection during winter, little is known about their annual-cycle movements. We used satellite telemetry to identify individual variation in migratory routes and breeding areas for black scoters wintering along the Atlantic Coast, to assess migratory connectivity among wintering, staging, breeding, and molt sites, and to examine effects of breeding site attendance on movement patterns and phenology. Black scoters occupied wintering areas from Canadian Maritime provinces to the southeastern United States. Males used an average of 2.5 distinct winter areas compared to 1.1 areas for females, and within-winter movements averaged 1,256 km/individual. Individuals used an average of 2.1 staging sites during the 45-day pre-breeding migration period, and almost all were detected in the Gulf of St. Lawrence. Males spent less time at breeding sites and departed them earlier than females. During post-breeding migration, females took approximately 25 fewer days than males to migrate from breeding sites to molt and staging sites, and then wintering areas. Most individuals used molt sites in James and Hudson bays before migrating directly to coastal wintering sites, which took approximately 11 days and covered 1,524 km. Males tended to arrive at wintering areas 10 days earlier than females. Individuals wintering near one another did not breed closer together than expected by chance, suggesting weak spatial structuring of the Atlantic population. Females exhibited greater fidelity (4.5 km) to previously used breeding sites compared to males (60 km). A substantial number of birds bred west of Hudson Bay in the Barrenlands, suggesting this area is used more widely than believed previously. Hudson and James bays provided key habitat for black scoters that winter along the Atlantic Coast, with most individuals residing for >30% of their annual cycle in these bays. Relative to other species of sea duck along the Atlantic Coast, the Atlantic population of black scoter is more dispersed and mobile during winter but is more concentrated during migration. These results could have implications for future survey efforts designed to assess population trends of black scoters. (c) 2021 The Wildlife Society.
Times Cited in Web of Science Core Collection: 3 Total Times Cited: 3 Cited Reference Count: 91
Keywords: migration; SELECTION; WING MOLT; Melanitta americana; SEA DUCKS; ECOLOGY; HABITAT USE; annual cycle; phenology; REMIGIAL MOLT; PACIFIC COAST; black scoter; LONG-DISTANCE MIGRATION; MELANITTA-NIGRA; movement; WINTERING SURF SCOTERS

Spatially explicit network analysis reveals multi-species annual cycle movement patterns of sea ducks - Lamb, J. S.; Paton, P. W. C.; Osenkowski, J. E.; Badzinski, S. S.; Berlin, A. M.; Bowman, T.; Dwyer, C.; Fara, L. J.; Gilliland, S. G.; Kenow, K.; Lepage, C.; Mallory, M. L.; et al. (ECOLOGICAL APPLICATIONS, 2019)
Conservation of long-distance migratory species poses unique challenges. Migratory connectivity, that is, the extent to which groupings of individuals at breeding sites are maintained in wintering areas, is frequently used to evaluate population structure and assess use of key habitat areas. However, for species with complex or variable annual cycle movements, this traditional bimodal framework of migratory connectivity may be overly simplistic. Like many other waterfowl, sea ducks often travel to specific pre- and post-breeding sites outside their nesting and wintering areas to prepare for migration by feeding extensively and, in some cases, molting their flight feathers. These additional migrations may play a key role in population structure, but are not included in traditional models of migratory connectivity. Network analysis, which applies graph theory to assess linkages between discrete locations or entities, offers a powerful tool for quantitatively assessing the contributions of different sites used throughout the annual cycle to complex spatial networks. We collected satellite telemetry data on annual cycle movements of 672 individual sea ducks of five species from throughout eastern North America and the Great Lakes. From these data, we constructed a multi-species network model of migratory patterns and site use over the course of breeding, molting, wintering, and migratory staging. Our results highlight inter- and intra-specific differences in the patterns and complexity of annual cycle movement patterns, including the central importance of staging and molting sites in James Bay, the St. Lawrence River, and southern New England to multi-species annual cycle habitat linkages, and highlight the value of Long-tailed Ducks (Calengula haemalis) as an umbrella species to represent the movement patterns of multiple sea duck species. We also discuss potential applications of network migration models to conservation prioritization, identification of population units, and integrating different data streams.
Times Cited in Web of Science Core Collection: 14 Total Times Cited: 14 Cited Reference Count: 83
Keywords: migration; connectivity; Long-tailed Duck; CONSERVATION; sea duck; DYNAMICS; molt; eider; PACKAGE; LONG-DISTANCE MIGRATION; CENTRALITY; flyway; HABITAT PATCHES; network analysis; Scoter; SITE-FIDELITY; stopover; TAILED DUCKS; WORLDS

Assessing year-round habitat use by migratory sea ducks in a multi-species context reveals seasonal variation in habitat selection and partitioning - Lamb, J. S.; Paton, P. W. C.; Osenkowski, J. E.; Badzinski, S. S.; Berlin, A. M.; Bowman, T.; Dwyer, C.; Fara, L. J.; Gilliland, S. G.; Kenow, K.; Lepage, C.; Mallory, M. L.; et al. (ECOGRAPHY, 2020)
Long-distance migration presents complex conservation challenges, and migratory species often experience shortfalls in conservation due to the difficulty of identifying important locations and resources throughout the annual cycle. In order to prioritize habitats for conservation of migratory wildlife, it is necessary to understand how habitat needs change throughout the annual cycle, as well as to identify key habitat sites and features that concentrate large numbers of individuals and species. Among long-distance migrants, sea ducks have particularly complex migratory patterns, which often include distinct post-breeding molt sites as well as breeding, staging and wintering locations. Using a large set of individual tracking data (n = 476 individuals) from five species of sea ducks in eastern North America, we evaluated multi-species habitat suitability and partitioning across the breeding, post-breeding migration and molt, wintering and pre-breeding migration seasons. During breeding, species generally occupied distinct habitat areas, with the highest levels of multi-species overlap occurring in the Barrenlands west of Hudson Bay. Species generally preferred flatter areas closer to lakes with lower maximum temperatures relative to average conditions, but varied in distance to shore, elevation and precipitation. During non-breeding, species overlapped extensively during winter but diverged during migration. All species preferred shallow-water, nearshore habitats with high productivity, but varied in their relationships to salinity, temperature and bottom slope. Sea ducks selected most strongly for preferred habitats during post-breeding migration, with high partitioning among species; however, both selection and partitioning were weaker during pre-breeding migration. The addition of tidal current velocity, aquatic vegetation presence and bottom substrate improved non-breeding habitat models where available. Our results highlight the utility of multi-species, annual-cycle habitat assessments in identifying key habitat features and periods of vulnerability in order to optimize conservation strategies for migratory wildlife.
Times Cited in Web of Science Core Collection: 10 Total Times Cited: 10 Cited Reference Count: 95
Keywords: common eider; habitat suitability; long-tailed duck; mergini; partitioning; scoter; BIRDS; COMMUNITIES; MOVEMENTS; POPULATION; CONSERVATION; MODELS; EIDERS; WINTER; LONG-DISTANCE MIGRATION; AREAS

Implanted satellite transmitters affect sea duck movement patterns at short and long timescales - Lamb, J. S.; Paton, P. W. C.; Osenkowski, J. E.; Badzinski, S. S.; Berlin, A. M.; Bowman, T.; Dwyer, C.; Fara, L. J.; Gilliland, S. G.; Kenow, K.; Lepage, C.; Mallory, M. L.; et al. (CONDOR, 2020)
Studies of the effects of transmitters on wildlife often focus on survival. However, sublethal behavioral changes resulting from radio-marking have the potential to affect inferences from telemetry data and may vary based on individual and environmental characteristics. We used a long-term, multi-species tracking study of sea ducks to assess behavioral patterns at multiple temporal scales following implantation of intracoelomic satellite transmitters. We applied state-space models to assess short-term behavioral patterns in 476 individuals with implanted satellite transmitters, as well as comparing breeding site attendance and migratory phenology across multiple years after capture. In the short term, our results suggest an increase in dispersive behavior immediately following capture and transmitter implantation; however, behavior returned to seasonally average patterns within similar to 5 days after release. Over multiple years, we found that breeding site attendance by both males and females was depressed during the first breeding season after radio-marking relative to subsequent years, with larger relative decreases in breeding site attendance among males than females. We also found that spring and breeding migrations occurred later in the first year after radio-marking than in subsequent years. Across all behavioral effects, the severity of behavioral change often varied by species, sex, age, and capture season. We conclude that, although individuals appear to adjust relatively quickly (i.e. within 1 week) to implanted satellite transmitters, changes in breeding phenology may occur over the longer term and should be considered when analyzing and reporting telemetry data.
Times Cited in Web of Science Core Collection: 10 Total Times Cited: 10 Cited Reference Count: 65
Keywords: Common Eider; White-winged Scoter; Surf Scoter; Long-tailed Duck; COMMON EIDERS; Black Scoter; SURVIVAL; HABITAT USE; SURF SCOTERS; BEHAVIOR; phenology; RADIO TRANSMITTERS; RADIOTRANSMITTERS; SPECTACLED EIDERS; marking; PERCUTANEOUS ANTENNAS; PERFORMANCE; tracking

An evaluation of marine bird population trends following the Exxon Valdez oil spill, Prince William Sound, Alaska - Lance, Brian K.; Irons, David B.; Kendall, Steven J.; McDonald, Lyman L. (Marine Pollution Bulletin, 2001)
We examined post-spill trends (1989-1998) of marine bird populations in Prince William Sound (PWS) following the Exxon Valdez oil spill (EVOS) to evaluate recovery of injured taxa. Two criteria were employed. First, we examined population trends of injured taxa only in the oiled area of PWS using regression models. Second, we examined population trends of injured taxa in the oiled area relative to the unoiled area using homogeneity of the slopes tests. We considered a population recovering if there was a positive trend using either criteria. We considered a population not recovering if there was no trend using either criteria or a negative trend in the oiled area. A significant negative trend in the oiled area relative to the unoiled area was considered a continuing and increasing effect. Most taxa for which injury was previously demonstrated were not recovering and some taxa showed evidence of increasing effects nine years after the oil spill. Four taxa (loons Gavia spp, Harlequin Duck Histrionicus histrionicus, Bufflehead Bucephala spp, and North-western Crow Corvus caurinus) showed weak to very weak evidence of recovery. None of these taxa showed positive trends in both winter and summer. Nine taxa (grebes Podiceps spp, cormorants Phalacrocorax spp, Black Oystercatcher Haematopus bachmani, Mew Gull Larus canus, Glaucous-winged Gull Larus glaucescens, terns Sterna spp, murres Uria spp, Pigeon Guillemot Cepphus columba, and murrelets Brachyramphus spp) showed no evidence of recovery during summer or winter. Four taxa (scoters Melanitta spp, mergansers Mergus spp, golden-eyes Bucephala spp, and Black-legged Kittiwake Rissa tridactyla) showed evidence of continuing, increasing effects. We showed evidence of slow recovery, lack of recovery, and divergent population trends in many taxa which utilize shoreline and nearshore habitats where oil is likely to persist. Potential lingering spill effects and natural variability appear to be acting in concert in delaying recovery of many PWS bird populations.
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons; Contaminants

Petroleum hydrocarbon contamination in Nelson Lagoon, Alaska, sampling three different matrices - Lance, E. W.; Matz, A. C.; Reeves, M. K.; Verbrugge, L. A. (Marine Pollution Bulletin, 2012)
Times Cited: 1 Lance, Ellen W. Matz, Angela C. Reeves, Mari K. Verbrugge, Lori A. 1
Keywords: Nonbreeding Seasons; Contaminants; Polysticta stelleri; Steller's eider

Harlequin duck recovery from the Exxon Valdez oil spill: A population genetics perspective - Lanctot, Richard; Goatcher, Buddy; Scribner, Kim; Talbot, Sandy; Pierson, Barbara; Esler, Daniel; Zwiefelhofer, Denny (Auk, 1999)
Concerns about Harlequin Duck (Histrionicus histrionicus) population recovery following the Exxon Valdez oil spill led biologists to ask whether birds located in different molting and wintering areas belong to genetically distinct and, thus, demographically independent populations. Owing to the lack of direct observations of movements among marine areas, three classes of genetic markers that differed in mode of inheritance were used to evaluate the degree of genetic differentiation among wintering areas within Prince William Sound (PWS) and the Alaska Peninsula and Kodiak Archipelago (APKA). We could not reject the null hypothesis that the wintering aggregations within each region are composed of a single genetically panmictic population. Differences in genotype frequencies among wintering locations within PWS and APKA were low and nonsignificant for all three classes of markers. Furthermore, we saw no evidence for deviations in Hardy-Weinberg equilibrium or gametic disequilibriumbetween loci within a winter collection site as would be expected if these locales were composed of individuals from reproductively isolated (and genetically distinct) breeding locales. Finally, no evidence for significant structuring was noted between PWS and APKA. Lack of spatial genetic structuring could be due to the cumulative effects of low levels of gene flow over long time periods, low levels of gene flow by immature birds moving between marine habitats, or to episodic dispersal caused by habitat alteration (e.g. volcanic eruptions). Harlequin Ducks are likely to recolonize or enhance populations in areas recovering from environmental damage via emigration of birds from non-affected areas. Demographic studies suggest, however, that levels of movements are low, and that population recovery by emigration is a long-term process.
Keywords: Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Contaminants; Population Delineation

Alaskan oilfield development and glaucous gulls - Lanctot, Richard B.; Gleason, Jeffrey S. (Arctic, 2006)
Keywords: Conservation; Breeding Season; Common Eider; Clangula hyemalis; Long-tailed Duck; Somateria mollissima

COMMON MERGANSERS MERGUS MERGANSER USE WINGS TO PURSUE A FISH UNDERWATER - Lapsansky, A. B.; Armstrong, R. H. (MARINE ORNITHOLOGY, 2022)
Common Mergansers Mergus merganser dive into lakes, rivers, and coastal waters to feed on fish and other aquatic prey. This species and others in the genus Mergus are traditionally classified as foot-propelled divers. When submerged, mergansers are expected to swim by kicking their feet, holding their wings close to their bodies. Here, we report, with video evidence, an event in which four mergansers used their wings underwater to chase down and capture a large fish. Documentation of wing use by this classically defined "foot-propelled diver" illustrates the gaps in our understanding of avian diving physiology, hydrodynamics, and behavior.
Times Cited in Web of Science Core Collection: 1 Total Times Cited: 1 Cited Reference Count: 30
Keywords: Mergus merganser; diving; foot-propelled; LIFT; PROPULSION; SWIM SPEEDS; swimming; wing-propelled

Influence of annual variation in food supply on abundance of wintering common eiders Somateria mollissima - Larsen, Jesper K.; Guillemette, Magella (Marine Ecology Progress Series, 2000)
We investigated how the annual variation in the abundance of wintering common eiders Somateria mollissima was related to the abundance of benthos over 4 yr. The study was conducted at 2 sites, Tuno Knob and Ringebjerg Sand, Denmark, from 1994 to 1998. Benthos was sampled along permanent transects in November, and common eiders counted and localized from observation towers during the winter. The benthic community was dominated by the blue mussel Mytilus edulis, with sizes varying with depth. Small and intermediary-sized individuals were primarily found in 0 to 6 m depth, and large individuals exclusively in 6 to 12 m depth. The pattern of variation in abundance of common eiders matched that of the benthos in 0 to 6 m depth, where they were mostly found, but not in 6 to 12 m depth. Based on a bioenergetic model of food consumption, we estimated that common eiders during the 3rd and 4th years exploited between 22 and 64% of the entire benthic community biomass in 0 to 6 m depth, compared to ltoreq3% in 6 to 12 m depth. We conclude that common eiders tracked annual variation in food abundance, primarily related to the presence of small and intermediary-sized blue mussels.
Keywords: Abundance, Distribution, and Trends; Common Eider; Nonbreeding Seasons; Somateria mollissima; Trophic Interactions; Habitat

Effects of wind turbines on flight behaviour of wintering common eiders: implications for habitat use and collision risk - Larsen, Jesper K.; Guillemette, Magella (Journal of Applied Ecology, 2007)
1.Wind energy is a fast-growing renewable energy source and many offshore wind parks will be erected in shallow waters (< 40 m deep) where various coastal bird species are found. The two main issues regarding offshore wind farms and birds are disturbance and collision risk. We studied the effect of wind turbines on the flight behaviour of wintering common eiders Somateria mollissima in order to identify the properties that cause disturbance and the factors that may increase their risk of collision.2. The study was conducted at Tuno Knob offshore wind park in the Kattegat, Denmark. We attracted birds though the use of decoys located at increasing distances from the wind park. To discriminate between the potential disturbance effect of the standing towers from that of the revolving rotor blades, wind turbines were switched on or off alternately during 10 experimental trials.3. Common eiders reacted strongly to the presence of wind turbines. The number of flying birds was significantly related to flight corridor location and position of the decoy group. That behavioural reaction was interpreted to be a consequence of their high speed and low-manoeuvrability flight occurring within the vertical height range of the wind turbines. The number of landing birds also reacted to the position of the decoy group in relation to proximity to the turbines, with the greatest effects observed within the wind park. Such avoidance behaviour might decrease use of otherwise suitable habitat.4. The movement and noise of rotors affected neither the number of common eiders flying within corridors nor the number of birds reacting to decoys. This suggests that the avoidance behaviour observed was caused by the presence of the structures themselves and that eiders use vision when avoiding human-made structures.5. Synthesis and applications. This study has demonstrated that common eiders avoid flying close to or into the Tuno Knob wind park. This behaviour may result in a reduction in habitat availability within and around wind parks, and raises concerns about the possible impact of the extensive development of large-scale wind parks in shallow offshore waters, which are the main feeding areas for sea ducks and other marine birds. Our results indicate that the disturbance effect of revolving rotor blades is negligible during daylight hours but highlights the need for studies to be carried out during hours of darkness and conditions of poor visibility (e.g. fog and snow). Until more insight is gained, we recommend caution when planning wind parks in areas of high sea duck densities.
Keywords: Conservation; Behavior; Common Eider; Nonbreeding Seasons; Somateria mollissima; Habitat

Disturbance effects of high-speed ferries on wintering sea ducks - Larsen, J. K.; Laubek, B. (Wildfowl, 2005)
Human offshore activities are increasingly threatening waterbird conservation interests. The impacts of disturbance by high-speed ferries on Common Eiders Somateria mollissima and Common Scoters Melanitta nigra were studied at a wintering site in the Kattegat Sea, Denmark. Spatial patterns of winter site use, close-range distribution patterns relative to ferry passages and escape distances were examined using aerial surveys and ferry-based observations. For Common Eiders, there was a suggestion of major disturbance impacts, i.e. birds displacing in response to the passage of ferries, within 500-1,000 m of the ferry route: a considerable proportion of flocks (> 10%) located within 400 m took flight in response to a passing ferry, and distributional impacts, including birds responding by swimming, were occasionally suggested within a distance of 500-1,000 m. Although distributional impacts could not be demonstrated with statistical significance within the Hjelm area (partly because of an apparently Limited food supply in the area around the ferry route), it is concluded that highspeed ferry disturbance, had the potential to reduce significantly habitat use within 500 m of the ferry route. Common Scoters tended to take flight further from the ferry route than Common Eiders, however, data were Limited and no conclusions could be made on displacement distances or possible impacts on habitat use. The results show that high-speed ferries may be an important source of disturbance that should be given due attention when the cumulative effects of offshore activities on site use by sea ducks are considered.
Keywords: Conservation; Behavior; Common Eider; Nonbreeding Seasons; Somateria mollissima; Black Scoter; Melanitta nigra

Trends in chronic marine oil pollution in Danish waters assessed using 22 years of beached bird surveys - Larsen, Jorn Lennart; Durinck, Jan; Skov, Henrik (Marine Pollution Bulletin, 2007)
Beached bird surveys provide an important tool for monitoring the level of oil pollution at sea, which is the most significant observable cause of death for a large number of waterbird species and pose a serious threat to wintering seabird populations. Linear regression analyses of oil rates from the Danish 22 year dataset show a decline in the oil pollution level in offshore areas of the eastern North Sea and Skagerrak and in near-shore parts of the Kattegat; but a worsening in the offshore areas of the Kattegat. These results raise concern for species such as common scoter, velvet scoter, eider and razorbill, for which the Kattegat serves as a globally important wintering area. It is recommended that surveillance for oil spills is intensified in inner Danish waters, and that action is taken to make responses towards offenders faster, and penalties for oil seepage higher. (c) 2007 Elsevier Ltd. All rights reserved.
Keywords: Common Eider; Melanitta fusca; Nonbreeding Seasons; White-winged Scoter; Contaminants; Somateria mollissima; Black Scoter; Melanitta nigra

The mussel path - Using the contaminant tracer, Ecotracer, in Ecopath to model the spread of pollutants in an Arctic marine food web - Larsen, L. H.; Sagerup, K.; Ramsvatn, S. (Ecological Modelling, 2016)
As the polar ice cap is receding, shipping in the Arctic seas becomes easier, and both destination and Atlantic-Pacific transit shipping is expected to increase. Thereby, the risk of accidents increase. Immediate negative impacts are expected from oil spills through the acute mortality for marine organisms, especially from heavy fuel oil (HFO). Marine Diesel oil (MDO) is therefore suggested as a preferable fuel for ships operating in Arctic waters. However, Polycyclic Aromatic Hydrocarbons (PAHs) are toxic components in both types of fuel, are highly bioavailable and can transfer up the food chain. A spill of MDO following a shipwreck could therefore have impacts beyond the spill site and long after the diesel has spread and evaporated. We model the spread of PAHs from a fictitious spill of MDO in the Pechora Sea (South Eastern Barents Sea) using the contaminant tracer module Ecotracer, in the Ecopath modelling software. We address the effects on the food-web including long term effects by combining toxicology and food web modelling. Ecotracer assumes that pollutants follow the biomass passively through the system, and degradation of pollutants is following user specified rates. By combining in natura measurements of PAHs in seawater and in blue mussels (Mytilus edulis) recorded at an accidental MDO spill site, with experiments conducted on the red king crab (Paralithodes camtschaticus) and blue mussels, we derived values as inputs into the model. The Ecotracer predicted that the pollution in the mussels will spread throughout the food-web, especially to the top predators of mussels, king eider (Somateria spectabilis) and Atlantic walrus (Odobenus rosmarus rosmarus) and also from snow crab (Chionoecetes opilio) to seals and toothed whales. (C) 2015 Elsevier B.V. All rights reserved.
Larsen, Lars-Henrik Sagerup, Kjetil Ramsvatn, Silje
Keywords: Conservation; Contaminants; King Eider; Somateria spectabilis; Trophic Interactions

Effects of an extensive Prymnesium polylepis bloom on breeding eiders in the Baltic Sea - Larsson, K.; Hajdu, S.; Kilpi, M.; Larsson, R.; Leito, A.; Lyngs, P. (Journal of Sea Research, 2014)
The effects of an extensive bloom of the potentially toxic Prymnesium polylepis (Haptophyta) on breeding eiders (Somateria mollissima) in the Baltic Sea were analysed. Increasing abundances of the alternate stage P. polylepis was detected by a marine monitoring programme in the autumn 2007. The bloom peaked between March and May 2008 in the southern, central and northwestern Baltic Proper and abundances of up to 5 x 10(6) cells l(-1) were recorded. At several sites P. polylepis constituted between 30 and 90% of the total phytoplankton biovolume. The flagellate was only recorded in low numbers in the northeastern Baltic Proper and Gulf of Finland. The abundances were low in 2007, 2009 and 2010. In 28 eider colonies situated in the southern and central Baltic Proper, sharp and synchronous declines in the number of nesting eiders were observed from 2007 to 2008. In colonies on Gotland in the central Baltic Proper, a 76% decrease, from 6650 nests to 1620 nests, was followed by increases in 2009 and 2010, although not up to numbers observed in 2007. At Utklippan and Ertholmene in the southern Baltic Proper, the observed decreases of 55%, from 144 to 65 nests, and 36%, from 1660 to 1060 nests, respectively, between 2007 and 2008, were followed by increases in 2009 and 2010 up to the level observed in 2007. By contrast, no general decline of the number of nesting eiders was observed from 2007 to 2008 in 75 colonies in the northeastern Baltic Proper and Gulf of Finland. Hence, the spatial distribution of the P. polylepis bloom in 2008 closely matched the observed distribution of extensive non-breeding of female eiders. We suggest that the intensive spring bloom of P. polylepis, either through a toxic or non-toxic pathway, affected the main benthic food of eiders, i.e. blue mussels (Mytilus trossulus x Mytilus edulis), at pre-breeding foraging sites close to the breeding sites, and, subsequently, the body condition of adult female eiders and their breeding propensity. (C) 2014 The Authors. Published by Elsevier B.V. All rights reserved.
Larsson, K. Hajdu, S. Kilpi, M. Larsson, R. Leito, A. Lyngs, P.
Keywords: Breeding Season; Common Eider; Contaminants; Somateria mollissima; Productivity; Abundance, Distribution, & Trends

Effects of oil spills on wintering Long-tailed Ducks Clangula hyemalis at Hoburgs bank in central Baltic Sea between 1996197 and 2003104 - Larsson, Kjell; Tyden, Lars (Ornis Svecica, 2005)
The Baltic Sea is an important marine area for wintering birds. Surveys in the 1990s showed that more than 25 % of the European Long-tailed Duck Clangula hyemalis population wintered at Hoburgs bank and east of Gotland. A shipping route with very frequent traffic goes from southwest Baltic Sea via Oland, Hoburgs bank and east of Gotland to the Gulf of Finland. In year 2000 about 58 500 ships passed east of Oland along this route. Hundreds of oils spills are registered along the route each year. Weekly surveys of oiled birds at southern Gotland and analyses of birds that had drown in fish nets showed that tens of thousands of Long-tailed Ducks were injured by oil each year in central Baltic Sea. Of 998 birds that drowned in fish nets at Hoburgs bank 11.8 % were found to have oil in the plumage. There was no clear relationship between the number of oiled birds observed and the number of registered oil spills in different years. Many sea duck have a life history in which variable or low productivity is compensated for by relatively high adult survival. This makes sea duck populations very susceptible to extra adult mortality caused by oil spills.
Keywords: Nonbreeding Seasons; Clangula hyemalis; Long-tailed Duck; Contaminants

Animals Need Not Be Killed to Reveal Their Body-Burdens of Chlorinated Hydrocarbons - Larsson, P.; Lindegren, A. (Environmental Pollution, 1987)
The levels of persistent, lipophilic pollutants in different organs and body-fluids of birds are governed by partitioning, i.e. the levels are correlated. This implies that it may be possible to estimate the total body-burden of chlorinated hydrocarbons, without sacrificing the animals, by examining the levels in secretory fluid. This hypothesis was tested on the goosander, a fish-eating waterfowl. We found that levels of PCB and DDE in secretions from the uropyginal gland were linearly related to levels in the breast muscle. Thus, by estimating the amounts of persistent pollutants in water-repellent secretions, the total body-burden could be calculated.
Keywords: Contaminants; Common merganser; Mergus merganser

Nest location fidelity in the Common Eider Somateria mollissima at Utklippan in the Baltic Sea - Larsson, Rolf (Ornis Svecica, 2008)
Keywords: Breeding Season; Common Eider; Somateria mollissima; Dispersal

Notes on Summering Sea Ducks on Eastern Long Island - Latham, R. (Engelhardtia, 1971)
Keywords: Sea Ducks - General

Biochemical and clinical responses of Common Eiders to implanted satellite transmitters - Latty, C. J.; Hollmen, T. E.; Petersen, M. R.; Powell, A. N.; Andrews, R. D. (Condor, 2016)
Implanted biologging devices, such as satellite-linked platform transmitter terminals (PTTs), have been used widely to delineate populations and identify movement patterns of sea ducks. Although in some cases these ecological studies could reveal transmitter effects on behavior and mortality, experiments conducted under controlled conditions can provide valuable information to understand the influence of implanted tags on health and physiology. We report the clinical, mass, biochemical, and histological responses of captive Common Eiders (Somateria mollissima) implanted with PTTs with percutaneous antennas. We trained 6 individuals to dive 4.9 m for their food, allowed them to acclimate to this dive depth, and implanted them with PTTs. We collected data before surgery to establish baselines, and for 3.5 mo after surgery. The first feeding dive took place 22 hr after surgery, with 5 of 6 birds diving to the bottom within 35 hr of surgery. Plumage waterproofing around surgical sites was reduced <= 21 days after surgery. Mass; albumin; albumin: globulin ratio; aspartate aminotransferase; beta(1)-, beta(2)-, and gamma-globulins; creatine kinase; fecal glucocorticoid metabolites; heterophil: lymphocyte ratio; and packed cell volume changed from baseline on one or more of the postsurgery sampling dates, and some changes were still evident 3.5 mo after surgery. Our findings show that Common Eiders physiologically responded for up to 3.5 mo after surgical implantation of a PTT, with the greatest response occurring within the first few weeks of implantation. These responses support the need for postsurgery censor periods for satellite telemetry data and should be considered when designing studies and analyzing information from PTTs in sea ducks.
Latty, Christopher J. Hollmen, Tuula E. Petersen, Margaret R. Powell, Abby N. Andrews, Russel D.
Keywords: Behavior; Common Eider; Somateria mollissima; Physiology

Biochemical and clinical responses of Common Eiders to implanted satellite transmitters (vol 118, pg 489, 2016) - Latty, C. J.; Hollmen, T. E.; Petersen, M. R.; Powell, A. N.; Andrews, R. D. (CONDOR, 2018)
Some statistics in "Biochemical and clinical responses of Common Eiders to implanted satellite transmitters'' were miscalculated due to missing data. We provide corrected values for the affected variables. Corrected data did not affect the conclusions of the paper.
Times Cited in Web of Science Core Collection: 0 Total Times Cited: 0 Cited Reference Count: 1
Keywords: Somateria mollissima; sea duck; radio telemetry; biomarker; platform transmitter terminal; transmitter effect

Distribution and diurnal behavior of Steller's Eiders wintering on the Alaska Peninsula - Laubhan, Murray K.; Metzner, Keith A. (Condor, 1999)
We studied the distribution and activities of adult Steller's Eiders (Polysticta stelleri) during winter and spring on a deep-water embayment and a shallow lagoon along the Alaska Peninsula from September 1980 to May 1981. During the remigial molt, eiders were observed on Izembek Lagoon but not on Cold Bay. Following the flightless period, Izembek Lagoon continued to support 63-100% of eiders encountered during surveys. As ice cover on Izembek Lagoon increased, the number of birds decreased on Izembek Lagoon but increased on Cold Bay, suggesting that some eiders disperse to nearshore, deep-water habitats in close proximity to Izembek Lagoon during severe weather. Diurnal activity budgets indicated that the amount of time resting or engaged in aggression and alert activities was similar among locations, seasons, tidal stages, and sexes. In contrast, time spent foraging differed among seasons and locations but did not differ among tidal stages or sexes. Although time spent foraging wassimilar during winter and spring on Izembek Lagoon, eiders on Cold Bay foraged more during winter compared to spring. Synchronous diving was the dominant foraging strategy.
Keywords: Behavior; Abundance, Distribution, and Trends; Nonbreeding Seasons; Molt; Habitat; Polysticta stelleri; Steller's eider

The Role of Genetic Factors on Clutch Size and Egg Dimensions in the Common Eider Somateria-Mollissima - Laurila, T. (Finnish Game Research, 1988)
The amount of genetic variation in ecologically important characters can be used to predict the potential effect of natural selection of these traits. The proportion of genetic variation in clutch size and egg length and breadth in the eider was studied by estimating the repeatibility of these traits. The data comprised 18,388 eggs and 3846 clutches of 1209 ringed females having 2 to 7 clutches each. Estimation of the repeatabilty of egg dimensions was made using the measurements of 403 eggs in 91 clutches drawn from the original data. One-way analysis of variance was used to estimate the variance components needed for the estimation of repeatability. The estimate of repeatability was 0.31 .+-. 0.02 for clutch size, 0.49 .+-. 0.05 for egg length and 0.53 .+-. 0.05 for egg breadth. Previous estimates of genetic parameters obtained from wild bird populations, mostly from hole-nesting passerines, have been somewhat higher, averaging 0.4-0.5 for clutch size and 0.5-0.7 for egg dimensions. Estimates from waterfowl studies are comparable to those in this study. If the results are compared with the theory of animal breeding we can consider clutch size as a production trait with an intermediate proportion of genetic variation, and egg dimensions as quality traits with a high proportion of genetic variation. This suggests that these traits have enough genetic variation for a relatively rapid response to a potential directional selection.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Productivity

Nest Site Selection in the Common Eider Somateria-Mollissima Differences between the Archipelago Zones - Laurila, T. (Ornis Fennica, 1989)
The nest site selection and reproductive traits were studied in Eiders breeding in three zones of the Finnish archipelago. These differed in the degree of isolation (safety from terrestrial predators), the vegetation and human disturbance. The data were gathered in summer 1988 and comprised 52 islands and 1057 Eider nests. Both the numbers of Eiders and their density were higher in the outer zone, where the birds bred on all the islands In the inner zone, they preferred the smaller and most isolated islands. The nests were located further from the water and more of them were covered in the outer zone than elsewhere. Outer zone Eiders bred earliest and were shyest, and their nests were least frequently robbed. These differences were probably due to the earlier break-up of the ice, better protection from terrestrial predators and weaker human disturbance in the outer zone. In general, covered nests contained more eggs than open ones. The Eiders laid later and more of their nests were robbed on disturbed than on undisturbed islands. On open (well-isolated and less disturbed) islands, the nest density was higher, breeding occurred earlier and fewer nests were robbed. In the principal component analysis, the first principal component (interpreted as safety from predators) accounted for 43% of the variation in nest density and 20% of the variation in the distance of the nest from the shore, the laying date and flushing distance. The second principal component (interpreted as island size) explained 40% of the variation in the distance of the nest from the shore and 10% of the variation in nest density. The third principal component (in terpreted as archipelago zone) explained 56% of the variation in clutch size and 20% of the variation in the laying date and flushing distance of female Eiders. The Eiders preferred well-isolated islands that were not disturbed by humans and had enough vegetation to offer cover for the nest; the type of island (open vs. wooded) was not important, but the islands fulfilling these conditions were mostly open. Eiders were able to breed successfully in all zones, but the inner zone seemed to be a poorer breeding habitat, as human disturbance and terrestrial predators reduced the number of islands suitable for nesting.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Productivity; Habitat

Environmental and Genetic Factors Influencing Clutch Size Egg Volume Date of Laying and Female Weight in the Common Eider Somateria-Molissima - Laurila, T.; Hario, M. (Finnish Game Research, 1988)
The effect of environmental and genetic factors on clutch size, egg volume, date of laying and female weight, as well as the relationship between these traits were studied in the common eider (Somateria mollissima) in the Soderskar archipelago in the Gulf of Finland. Data on 370 females and 576 clutches were collected in 1981-85. The onset of breeding and female weight at the start of incubation seemed to mainly determined by the earliness or lateness of the particular spring in question. Within year, the date of laying affected egg volume and clutch size. Clutches laid later than the population mean had fewer and smaller eggs than those laid earlier than the population mean. Also, old breeders laid earlier and larger clutches than young breeders. In this study, heavy females at the start of incubation did not lay larger or more eggs nor earlier in relation to the population mean than lighter females. Females had genetically-determined preferences in the timing of breeding and a kind of "ideal" weights which they tried to attain. Temporal enviromental factors had the least influence on egg volume (repeatability, t, was about 70%), an intermediate effect on the date of laying and female weight (t .apprx. 40%), and the largest influence on clutch size (t .apprx. 30%).
Keywords: Breeding Season; Common Eider; Somateria mollissima; Productivity; Energetics and Nutrition

Estimates of Sea Duck Winter Populations of the Western Palearctic - Laursen, K. (Danish Review of Game Biology, 1989)
The present knowledge of the flyway populations of five sea duck species wintering in Western Palaearctic is reviewed. The estimates are mainly based on midwinter counts organised by IWRB in collaboration with national coordinators. Additionally information from various surveys is incorporated. Midwinter population sizes are presently estimated at: Scaup Aythya marila 200,000 individuals; Eider Somateria mollissima 3 million; Long-tailed Duck Clangula hyemalis 2 million; Common Scoter Melanitta nigra 800,000, and Velvet Scoter Melanitta fusca 250,000 individuals. The flyway population of Scaup is unchanged compared to the estimate made in the early 1970's while numbers of Eider, Long-tailed Duck, Common Scoter and Velvet Scoter have risen during the same period. An increase in the population size of Eider has already been documented. More efficient covering of sea areas by aircrafts and boats may be the reason for higher numbers of the other species. To obtain more exact information about population size, trends and distributions of sea ducks, the following is recommended: (1) intensification of midwinter counts; and (2) inclusion of the utilisation of aircraft and boats in the Eastern and Southern Baltic, in the Southern North Sea, off the Iberian and Northwest African coasts, and in the Black Sea.
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons

Winter Counts of Seabirds Off the Southwest Coast of Denmark - Laursen, K.; Frikke, J. (Dansk Ornitologisk Forenings Tidsskrift, 1987)
In the eastern part of the North Sea, off the southwest coast of Denmark, four aerial surveys were performed in January and February 1986. The number of Common Scoter was estimated at 200,000, laying in two flocks, one west of Blavands Huk and one west of Romo/Sylt. The number of Eiders was estimated at 100,000 this is more than usual, and many individuals lay outside the Wadden Sea, probably due to an extensive ice cover here. An influx of Eiders from the likewise frozen Baltic Sea may have contributed to the number. Densities of divers were estimated at 0-4 per km2 with a mean of 1.8. The highest density was found 10-20 km from the coast at a water depth of 10-20 m. The auks varied between 0 and 4 per km2 with a mean of 0.7. The highest density was found 20-30 km from the coast at a depth of 15-20 m.
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons

Assessment of sustainable management of staging waterbirds in the Danish Wadden Sea - Laursen, Karsten; Frikke, John (Wildfowl, 2006)
A large number of wildlife reserves have been established throughout Europe to protect migratory waterbirds. However, there has been little evaluation of whether they are being managed sustainably. The Danish Wadden Sea became a wildlife reserve in 1979 to manage hunting and public access to the site. This paper evaluates whether waterbirds are being managed in a sustainable manner, using the definition that bird numbers over the years should be either: 1) regulated by factors independent of human activity, or 2) be at least stable. The hypothesis was tested for 17 waterbird species, using 194 counts made from aircraft between 1980 and 2000 inclusive. The TrendSpotter programme was used to examine trends in numbers. Regression analysis with autoregressive error correction was used to assess the association between four factors (population size indices, population breeding success, plant primary production and biomass of Blue Mussel Mytilus edulis) thought to be affecting the numbers of waterbirds using the site each year. The results showed increasing trends in spring for Brent Goose Branta bernicla, Grey Plover Pluvialis squatarola and Bar-tailed Godwit Limosa lapponica, whereas numbers of Shelduck Tadorna tadorna, Pintail Anas acuta, Oystercatcher Haematopus ostralegus, Grey Plover, Curlew Numenius arquata and Common Gull Larus canus increased in autumn. Numbers of Brent Goose, Wigeon Anas penelope, Avocet Recurvirostra avocetta, Dunlin Calidris alpina, Bar-tailed Godwit, Black-headed Gun Larus ridibundus and Herring Gun L argentatus were all stable during autumn, as was Eider Somateria mollissima during winter. Mallard Anas platyrhynchos decreased during autumn, and the trends were uncertain for Teal Anas crecca and Knot Calidris canutus. Numbers of Brent Goose, Shelduck, Wigeon, Teal, Mallard and Avocet (during autumn) and Grey Plover (during spring) in the Danish Wadden Sea were correlated either with the population index, the breeding index or the primary production index. Thus numbers of seven species appear to be influenced by factors other than human activity in the Danish Wadden Sea, and the trends of 14 species were either stable or increasing. Moreover, for the five quarry species considered, numbers in the Danish Wadden Sea were either correlated with factors outside the area (Mallard, Pintail, Wigeon and Teal) or were stable despite a decrease in the total population size (Eider). Thus it is concluded that the wildlife reserve in the Danish Wadden Sea has been managed in a sustainable manner.
Keywords: Conservation; Abundance, Distribution, and Trends; Common Eider; Sea Ducks - General; Nonbreeding Seasons

Hunting from motorboats displaces Wadden Sea eiders Somateria mollissima from their favoured feeding distribution - Laursen, Karsten; Frikke, John (Wildlife Biology, 2008)
Hunting of ciders Somateria mollissima from motorboats is common in Danish marine waters, and to reduce hunting pressure oil ciders and other diving duck species in Denmark, motorboat hunting was banned within 42 marine sites covering an area of 2,934 km(2). although the effects of this regulation have to date not been examined. Our case study analyses the effects Of excluding motorboat hunting from an area of 682 km(2) of the Danish Wadden Sea (hereafter the 'Study Area') which also supported a large area of blue mussel beds, the preferred food for ciders. Our study covered the entire Danish Wadden Sea (total area 1,225 km(2)) during the hunting seasons (October-February) of 1980-2003 using 85 aerial surveys of ciders and motorboats used by hunters. Eider numbers increased by 56% in the Study Area following the ban oil motorboat hunting despite a 50% reduction in the eider flyway population over the same period. There was a significant negative relationship between the density of hunter motorboats and that of ciders on a small geographical scale (1.8-2.5 km). Motorboat hunting in the Study Area also affected eider distribution at larger geographical scales (4-12 km), displacing ciders from the Study Area offshore from the Wadden Sea into the North Sea. Following the ban on motorboat hunting, most ciders Occurred in the Study Area. Winter (21 December-31 January) body condition of ciders was greater in the Study Area than the body condition of ciders in the Offshore Area during autumn (20 October-20 December). Eider abundance relative to blue Mussel biomass significantly increased after motorboat hunting was banned ill the Study Area, but there was no such change during winter after the hunting ban. Since the ban on motorboat hunting in the Study Area, eider numbers throughout the entire Danish Wadden Sea seem to be regulated by total blue mussel biomass.
Keywords: Conservation; Abundance, Distribution, and Trends; Common Eider; Nonbreeding Seasons; Somateria mollissima

Accuracy of 'total counts' of waterbirds from aircraft in coastal waters - Laursen, Karsten; Frikke, John; Kahlert, Johnny (Wildlife Biology, 2008)
Estimating 'total counts' of waterbirds from aircraft is a widely used survey method, and we assessed the effectiveness of this method for geese, ducks, waders and gulls by comparing the results of counts from aircraft with ground counts in the Danish Wadden Sea during 1984-1998. In total, 47 counts were carried out in 12 counting sites and the results were compared for 18 waterbird species, which varied in abundance, flock size and degree of aggregation. Significantly greater numbers of waterbird species were identified from the ground than from aircraft (mean number: 16.1 vs 10.6 species). Depending on the accuracy of aerial counts compared to ground counts, the species were divided into three categories: a) brent goose Branta bernicla, shelduck Tadorna tadorna, mallard Anas platyrhynuchos, eider Somateria mollissima and oystercatcher Haematopus ostralegus had a high level of correspondence between densities obtained from ground and aerial counts (detection rate of >80% with no statistical difference between slopes and intercepts of the observed regression lines and the ideal lines (x = y), differences between mean densities of ground and aerial counts being < 15%); b) wigeon Anas penelope, teal A. crecca, grey plover Pluvialis squatarola, dunlin Calidris alpine, bar-tailed godwit Limosa lapponica, black-headed gull Larus ridibundus, common gull L. canus, herring gull L. argentatus, great black-backed gull L. marinus and common/arctic tern Sterna hirundo and S. paradisaea had a medium correspondence between densities obtained from the two platforms (detection rate of >55% with differences between the mean densities of ground and aerial counts of <30%; and c) redshank Tringa totanus, greenshank T. nebularia arquata and curlew Numenius arquata had a low correspondence between the densities obtained from the two platforms (detection rate of <55% and differences between the mean densities of ground and aerial counts of >30%). Species with a high and medium level of correspondence between the two platforms are mostly species that are numerous, of widespread occurrence, and found in large flocks. Species with a low correspondence are minority species, occurring scattered or in small flocks. We recommend to supplement aerial counts with ground counts at sites with mixed flocks of more dabbling duck species present to increase the accuracy of the count results.
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General; Techniques

Factors affecting escape distances of staging waterbirds - Laursen, Karsten; Kahlert, Johnny; Frikke, John (Wildlife Biology, 2005)
Escape distances (EDs) have been used to study sensitivity of waterbirds to different sources of disturbance, to design reserves for waterbirds, and to define eco-targets for the Wadden Sea management plan. However, the use of ED as an index of sensitivity has been criticised because it can be highly variable. Although some factors affecting variation in the EDs of species have been studied, there is still a need for further analysis of factors that may affect it. In this study, we analysed the EDs of 19 waterbird species (geese, ducks, waders and gulls) exposed to a walking person (N = 1,37 1) during autumn and spring 19801984 under controlled conditions in the Danish Wadden Sea. We analysed how EDs varied between species in relation to body mass and hunting and within species in relation to flock size and weather conditions. EDs increased significantly with species body mass, and quarry species (dabbling ducks, curlew Numenius arquata, golden plover Pluvialis apricaria, common gull Larus canus and black-headed gull L. ridibundus) had longer EDs than non-quarry species when corrected for body mass. EDs increased with flock size in dabbling ducks and nine waterbird species in autumn and two waterbird species in spring. In autumn an inverse relationship was found between visibility and ED for dabbling ducks and five wader species. An inverse relationship was also found between wind force and ED for three wader species, but this relationship was found to be positive for two wader species. Several factors affected EDs, and EDs measured in one region may not apply to other regions. Based on our results it is recommended that reserve borders (core area and buffer zones) are designed to take into account mean EDs as well as variation in EDs, with respect to local disturbance levels, flock size and target species.
Keywords: Behavior; Sea Ducks - General; Nonbreeding Seasons

Long-Term Changes in Nutrients and Mussel Stocks Are Related to Numbers of Breeding Eiders Somateria mollissima at a Large Baltic Colony - Laursen, K.; Moller, A. P. (Plos One, 2014)
Background: The Baltic/Wadden Sea eider Somateria mollissima flyway population is decreasing, and this trend is also reflected in the large eider colony at Christianso situated in the Baltic Sea. This colony showed a 15-fold increase from 1925 until the mid-1990's, followed by a rapid decline in recent years, although the causes of this trend remain unknown. Most birds from the colony winter in the Wadden Sea, from which environmental data and information on the size of the main diet, the mussel Mytilus edulis stock exists. We hypothesised that changes in nutrients and water temperature in the Wadden Sea had an effect on the ecosystem affecting the size of mussel stocks, the principal food item for eiders, thereby influencing the number of breeding eider in the Christianso colony. Methodology/Principal Finding: A positive relationship between the amount of fertilizer used by farmers and the concentration of phosphorus in the Wadden Sea (with a time lag of one year) allowed analysis of the predictions concerning effects of nutrients for the period 1925-2010. There was (1) increasing amounts of fertilizer used in agriculture and this increased the amount of nutrients in the marine environment thereby increasing the mussel stocks in the Wadden Sea. (2) The number of eiders at Christianso increased when the amount of fertilizer increased. Finally (3) the number of eiders in the colony at Christianso increased with the amount of mussel stocks in the Wadden Sea. Conclusions/Significance: The trend in the number of eiders at Christianso is representative for the entire flyway population, and since nutrient reduction in the marine environment occurs in most parts of Northwest Europe, we hypothesize that this environmental candidate parameter is involved in the overall regulation of the Baltic/Wadden Sea eider population during recent decades.
Laursen, Karsten Moller, Anders Pape
Keywords: Common Eider; Somateria mollissima; Productivity; Trophic Interactions; Habitat; Abundance, Distribution, & Trends

Your tools disappear when you stop eating: phenotypic variation in gizzard mass of eiders - Laursen, K.; Moller, A. P. (Journal of Zoology, 2016)
Animals show phenotypic flexibility in their digestive system in response to seasonal changes in diet, activity, metabolic rate and reproduction. Many birds are capital breeders that alternate between periods of extensive feeding used for storage and periods of fasting during reproduction. Here, we analyzed the mass of the gizzard (gizzard mass without content) in 885 male and 348 female adult common eiders Somateria mollissima shot by Danish hunters during winter and spring in relation to alternating periods of foraging and fasting during reproduction. Gizzard mass of adult female eiders varied annually from 31g (N=25) during reproduction to 119g during pre-breeding (N=314), or almost a four-fold difference in mass. During winter, both male and female eiders with large gizzard mass had eaten a larger number of preferred blue mussels Mytilus edulis that constitute the main food. Adult female eiders with large gizzard mass had eaten larger but not more mussels. Individual adult females with large gizzard mass that had larger numbers of mussels in their gizzards were in superior body condition. These findings of phenotypic flexibility in gizzard mass show that individuals with larger gizzards consuming larger food items had an advantage in terms of superior body condition, potentially allowing for elevated reproductive success.
Laursen, K. Moller, A. P.
Keywords: Common Eider; Somateria mollissima; Physiology; Energetics and Nutrition

Brain mass explains prey size selection better than beak, gizzard and body size in a benthivorous duck species - Laursen, K.; Moller, A. P. (PLOS ONE, 2021)
Prey size selection in some bird species is determined by the size of the beak. However, we assumed for bird species swallowing whole prey that a cognitive process may be involved. As cognitive feature, brain mass was used. We hypothesized that the mass of the brain was more strongly positively correlated with prey size than morphological features such as beak volume, gizzard mass and body mass. We tested this hypothesis on eiders Somateria mollissima that swallow the prey whole, by using mean and maximum size of nine prey categories. Eiders were collected at the main wintering grounds in Denmark. As index of brain mass we used head volume, which is positively correlated with brain mass (r(2) = 0.73). Head volume of eiders was significantly, positive correlated with mean and maximum size of blue mussels Mytilus edulis, razor clams Ensis directus and all prey sizes combined and the maximum size of draft whelk Hinia reticulata and conch Buccinum undatum. Gizzard mass was also significantly positively correlated with maximum size of draft whelk and conch. Beak volume and body mass was not significantly correlated with the size of any of the nine food items. Analyses of effect size for organs showed that head volume was positively related to prey size, whereas beak volume, gizzard mass and body mass did not show a significant positive relationship. These results indicate that cognitive processes connected to brain mass may be involved in prey size selection by eiders.
Times Cited in Web of Science Core Collection: 0 Total Times Cited: 0 Cited Reference Count: 49
Keywords: COMMON EIDERS; SOMATERIA-MOLLISSIMA; EVOLUTION; STRATEGIES; MYTILUS-EDULIS; PERFORMANCE; BLUE MUSSELS; DISPLACEMENT; GAPE WIDTH; HEAD SIZE

Allocation of body reserves during winter in eider Somateria mollissima as preparation for spring migration and reproduction - Laursen, K.; Moller, A. P.; Haugaard, L.; Ost, M.; Vainio, J. (JOURNAL OF SEA RESEARCH, 2019)
Capital breeders, such as the eider duck Somateria mollissima, accumulate resources before the start of breeding. Eiders preferentially feed on blue mussels Mytilus edulis to build up body condition during winter. We explored how body condition and gizzard mass of wintering eiders relate to mussel quality and quantity, winter climate and body condition of females at the breeding grounds. Body condition during winter (defined as scaled body mass index) of eiders increased during winter and the magnitude of the effect depended on age and mussel quality. Gizzard mass of eiders increased during winter with effects of mussel quality, mussel stocks and sex. Body condition in winter of adult females increased from the first half of January to the second half of February on average by 1.5%, equal to c. 96 g. During the same period gizzard mass of adult females increased by 12.2%, i.e., a nearly ten-fold increase compared to that observed in body condition in winter. Body condition of females at the breeding grounds in Finland (defined as body condition at hatching) was significantly positively correlated with gizzard mass in winter, but not significantly correlated with body condition in winter. Thus, eiders allocate body reserves to increase gizzard mass but less so to increase body condition in winter. This can be considered an adaptive migratory strategy of these eiders, whereby large winter (pre-migratory) gizzards increase food processing capacity, making it possible for eiders to arrive at the breeding grounds with superior body condition and a high reproductive potential.
Times Cited in Web of Science Core Collection: 14 Total Times Cited: 16 Cited Reference Count: 66
Keywords: Somateria mollissima; SURVIVAL; SIZE; MASS; STRATEGIES; WADDEN SEA; NUMBERS; Blue mussel; Body condition in winter; Gizzard mass; INCOME DICHOTOMY; Mussel quality; Mussel stocks; QUALITY; SITE; SUCCESS; Winter climate

N-Isotopes in Feathers and Abundance of Eiders Respond to Nutrients in Seawater - Laursen, K.; Moller, A. P.; Hobson, K. A. (ECOSYSTEMS, 2019)
Nitrification of the environment has resulted from tremendous increases in the use of fertilizers for crop plants. This has increased runoff to coastal marine areas with consequences for primary production, benthos and upper trophic-level consumers, including sea ducks such as eiders Somateria mollissima. This species primarily relies on filter-feeding bivalves, especially blue mussels Mytilus edulis. Stable isotopes of nitrogen (measured as delta N-15) are incorporated in the feathers of eiders during molt at a constant rate reflecting the amount in food eaten. We examined if delta N-15 values in feathers can link eiders to the nitrogen loads in the marine waters surrounding Denmark, which is the main wintering grounds for the Baltic/Wadden Sea eider population. We also assessed how the abundance of eiders is related to nutrients and dead zones with oxygen deficit. During 2014-2018 we collected samples from 489 eiders, and of these 100 were analyzed for stable isotopes delta N-15. Eider feather delta N-15 was positively related to nitrogen abundance in marine waters. Local aggregations of eiders in late summer (the molting period) and in winter increased with the amount of nitrogen in the marine environment. Large eiders took longer to molt, they molted later and the daily growth increments of feathers were larger. Finally, larger eiders and eiders in higher numbers occurred in areas with hypoxia. These findings show that anthropogenic inputs to the coastal marine environment positively influence the abundance and aggregations of eiders.
Times Cited in Web of Science Core Collection: 2 Total Times Cited: 2 Cited Reference Count: 56
Keywords: Somateria mollissima; COMMON EIDERS; SOMATERIA-MOLLISSIMA; STABLE-ISOTOPES; IMPACTS; molt; STRATEGIES; WINTER; RATIOS; abundance; CARBON; dead zones; feather growth; HYPOXIA; nitrification; nitrogen; oxygen deficit

Dynamic group size and displacement as avoidance strategies by eiders in response to hunting - Laursen, K.; Moller, A. P.; Holm, T. E. (Wildlife Biology, 2016)
Hunting by humans constitutes a major source of mortality that selects for avoidance strategies. Group formation in eiders Somateria mollissima in response to hunting from motorboats was studied in the Danish Wadden Sea as an avoidance strategy to humans. In autumn the birds' food demand and energy consumption are relatively low and the need for optimal feeding opportunities are not as essential as during winter. We tested the hypothesis that eiders aggregate in groups of variable size dependent on predation risk (hunting), season and site. During autumn at the preferred feeding sites eiders occur in small numbers and group size increase together with hunting activity. Opposite during winter, eiders occur in large numbers and group size decrease when hunting activity increase. Hunting activity displaced eiders to adjacent sites with no or low hunting intensity and low food availability where group size of eiders increase during both autumn and winter in relation to the overall hunting activity. The formation into larger groups when hunting activity increase is probably due to increasing effects of vigilance and dilution, whereas formation into smaller groups is assumed to reduce the eiders conspicuousness to hunters. This change in group size made it possible for eiders to forage in areas with high food availability and high hunting intensity, while minimizing the risk of being detected by hunters. When the largest numbers of hunters were present at the preferred feeding site, group sizes during both autumn and winter were 110-125 eiders, indicating an optimal group size in relation to hunting density. Eiders located outside preferred feeding sites were in poorer body condition, suggesting that displacement was a suboptimal decision caused by hunting. We conclude that eiders adopted regrouping and displacement as two different strategies during hunting. Both strategies are tradeoffs between the risks of being detected by hunters and killed, and the benefits of feeding on mussel stocks thereby increasing body condition and hence fitness.
Laursen, Karsten Moller, Anders Pape Holm-, Thomas Eske
Keywords: Behavior; Common Eider; Somateria mollissima; Habitat; Nonbreeding season

Body condition of Eiders at Danish wintering grounds and at pre-breeding grounds in land - Laursen, K.; Moller, A. P.; Ost, M. (JOURNAL OF ORNITHOLOGY, 2019)
Breeding Eiders Somateria mollissima in the Baltic/Wadden Sea population have declined in recent decades, and several causes have been suggested. A recent study showed a modest increase in body mass from 2.20 kg by ca. 100 g during winter in Denmark, the main wintering area of the flyway population. This raises the question of whether Eiders could increase their body mass by an additional 200 g during pre-breeding to reach the average body mass of ca. 2.50 kg needed for successful reproduction. We analyzed this question by collecting Eiders at the Danish wintering grounds and pre-breeding grounds at land, Finland. Female Eiders increased their body condition (defined as scaled body mass index) from winter to the pre-breeding period, whereas males concurrently decreased in weight. The mean body mass of adult female Eiders was 2.23 kg in late winter, when they initiated spring migration. The mean female body mass at the pre-breeding grounds was 2.44 kg, an increase of 9.4% compared with females at the wintering grounds, while adult males decreased in weight by 3.4%. A decrease in gizzard mass was accompanied by a change in diet from large blue mussels Mytilus edulis at the wintering grounds to the small but more abundant mussels in the gizzard during pre-breeding. We conclude that female Eiders can reach a body mass of ca. 2.50 kg before breeding. Building up body condition for breeding is feasible at land; thus, difficulty in acquiring adequate resources for reproduction is unlikely to restrict local population size.
Times Cited in Web of Science Core Collection: 8 Total Times Cited: 9 Cited Reference Count: 53
Keywords: Somateria mollissima; COMMON EIDER; SOMATERIA-MOLLISSIMA; SIZE; WILD; STRATEGIES; SEA; MYTILUS-EDULIS; INDIVIDUAL QUALITY; SUCCESS; ARRIVAL; Body condition; Capital breeder; Eiders; Scaled body mass index

Variation in size and composition of Bufflehead (Bucephala albeola) and Barrow's Goldeneye (Bucephala islandica) eggs - Lavers, Jennifer L.; Thompson, Jonathan E.; Paszkowski, Cynthia A.; Ankney, C. Davison (Wilson Journal of Ornithology, 2006)
We investigated the relationships between egg nutrient constituents and fresh egg mass in Bufflehead (Bucephala albeola) and Barrow's Goldeneye (B. islandica). We found consistently positive relationships between egg mass and yolk, albumen, lipid, mineral, and water (absolute amounts); however, the proportions of nutrient components to fresh mass were highly variable in the eggs of both species (allometric relationships). In Bufflehead eggs, all components except mineral exhibited negative allometry with fresh egg mass. In Barrow's Goldeneye eggs, only mineral exhibited negative allometry, whereas yolk, lipid, and water all exhibited positive allometry with fresh egg mass. Overall, larger eggs of both species contained greater absolute amounts of nutrients; therefore, larger eggs were of better quality than smaller eggs. Nutrient content, however, was more highly correlated with mass in Barrow's Goldeneye eggs than in Bufflehead eggs. We propose that this may be due to the source of egg nutrients: because of their smaller body size, Buffleheads typically rely more on exogenous nutrients than Barrow's Goldeneyes.
Keywords: Breeding Season; Physiology; Energetics and Nutrition; Bucephala albeola; Bufflehead; Barrow's Goldeneye; Bucephala islandica

Organochlorines, brominated flame retardants and mercury levels in six seabird species from the Gulf of St. Lawrence (Canada): Relationships with feeding ecology, migration and molt - Lavoie, Raphael A.; Champoux, Louise; Rail, Jean-Francois; Lean, David R. S. (Environmental Pollution, 2010)
Concentrations of organochlorines (OCs), brominated flame retardants (BFRs) and mercury (Hg) were measured in eggs of six seabird species breeding in the Gulf of St. Lawrence, Canada. Stable nitrogen (delta N-15) and carbon (delta C-13) isotopes were used as ecological tracers to measure trophic level and connectivity with benthos, respectively. Concentrations, patterns as well as ecological tracers varied significantly between species. The sum of polychlorinated biphenyls (Sigma PCBs) was the most important group measured in all seabird species based on concentration followed generally by the sum of chlorinated pesticides (Sigma CPs), the sum of brominated flame retardants (Sigma BFRs) and finally total Hg (THg). Sigma PCBs, Sigma CPs and Sigma BFRs increased with trophic level, whereas THg did not. Only Sigma BFRs increased with a higher connectivity with the benthos. Seabird species resident to the Great Lakes-St. Lawrence ecosystem showed higher Hg and BFR levels than migratory species. Molt patterns were used to explain variations of contaminant levels. (C) 2010 Elsevier Ltd. All rights reserved.
Keywords: Breeding Season; Common Eider; Contaminants; Somateria mollissima

Phylogenomics reveals ancient and contemporary gene flow contributing to the evolutionary history of sea ducks (Tribe Mergini) - Lavretsky, P.; Wilson, R. E.; Talbot, S. L.; Sonsthagen, S. A. (MOLECULAR PHYLOGENETICS AND EVOLUTION, 2021)
Insight into complex evolutionary histories continues to build through broad comparative phylogenomic and population genomic studies. In particular, there is a need to understand the extent and scale that gene flow contributes to standing genomic diversity and the role introgression has played in evolutionary processes such as hybrid speciation. Here, we investigate the evolutionary history of the Mergini tribe (sea ducks) by coupling multi-species comparisons with phylogenomic analyses of thousands of nuclear ddRAD-seq loci, including Z-sex chromosome and autosomal linked loci, and the mitogenome assayed across all extant sea duck species in North America. All sea duck species are strongly structured across all sampled marker types (pair-wise species phi ST > 0.2), with clear genetic assignments of individuals to their respective species, and phylogenetic relationships recapitulate known relationships. Despite strong species integrity, we identify at least 18 putative hybrids; with all but one being late generational backcrosses. Most interesting, we provide the first evidence that an ancestral gene flow event between long-tailed ducks (Clangula hyemalis) and true Eiders (Somateria spp.) not only moved genetic material into the former species, but likely generated a novel species - the Steller's eider (Polysticta stelleri) - via hybrid speciation. Despite generally low contemporary levels of gene flow, we conclude that hybridization has and continues to be an important process that shifts novel genetic variation between species within the tribe Mergini. Finally, we outline methods that permit researchers to contrast genomic patterns of contemporary versus ancestral gene flow when attempting to reconstruct potentially complex evolutionary histories.
Times Cited in Web of Science Core Collection: 5 Total Times Cited: 5 Cited Reference Count: 129
Keywords: HARLEQUIN DUCKS; INFERENCE; Sea duck; ADMIXTURE; COMMON; Evolution; GENOME SEQUENCE; HYBRID SPECIATION; Hybridization; NATURAL HYBRIDIZATION; ORIGIN; PHYLOGENETIC ANALYSIS; Phylogenetics; Population genetics; TREE

Identifying demographic and environmental drivers of recruitment and population growth in a cavity-nesting sea duck population - Lawson, A. J.; Sedinger, J. S.; Taylor, E. J. (JOURNAL OF AVIAN BIOLOGY, 2017)
Traits with the greatest proportional effects on fitness are typically conserved, and traits with larger temporal variation frequently play a dominant role in population dynamics. We examined recruitment patterns and population growth in common goldeneyes Bucephala clangula (hereafter goldeneye), using Pradel mark-recapture models from a long-term nest box study (1997-2010). Our objectives were to estimate recruitment (f ) and population growth () relative to recruitment origin group (in-situ or unknown), investigate environmental and density dependent effects on these parameters, and evaluate potential immigration patterns. We detected group-specific differences for f (in-situ: 0.47 +/- 0.13 SE, unknown: 0.31 +/- 0.04), and the proportion of boxes occupied by goldeneyes the year prior to recruitment had a significant negative effect on recruitment for the in-situ group ( = -1.04; 85% CI -1.29, -0.78), and a positive effect for the unknown group ( = 0.45; 85% CI 0.30, 0.61). The negative box occupancy effect in the year prior to recruitment, when in-situ yearling goldeneyes prospect for potential nest sites, suggests that local nesting densities may limit recruitment of locally hatched females. We identified two competitive models for , which averaged 1.04 +/- 0.03 and included interactions between recruitment origin group and a linear temporal trend, and the proportion of ducklings marked two years prior. By evaluating all levels of marking effort on , we determined that even if all hatched ducklings were marked in a given year, the resulting in-situ was consistently lower than all observed population-level s during the study, indicating that individuals produced outside of study area nest boxes contributed to . Though female goldeneyes are considered highly philopatric, our results suggest that female natal and breeding dispersal may be more prevalent than previously thought, and the spatial scale at which these processes occur requires further investigation.
Times Cited in Web of Science Core Collection: 2 Total Times Cited: 2 Cited Reference Count: 45
Keywords: SURVIVAL; NATAL PHILOPATRY; DYNAMICS; GOLDENEYE BUCEPHALA-CLANGULA; RECAPTURE; BANDS; DELTA; DUCKLINGS; PARAMETERS; REPRODUCTIVE OUTPUT

Life history patterns, individual heterogeneity, and density dependence in breeding common goldeneyes of the northern boreal forest - Lawson, A. J.; Sedinger, J. S.; Taylor, E. J. (JOURNAL OF AVIAN BIOLOGY, 2017)
Life history patterns and their associated tradeoffs influence population dynamics, as they determine how individuals allocate resources among competing demographic traits. Here we examined life history strategies in common goldeneyes Bucephala clangula (hereafter goldeneye), a cavity-nesting sea duck, in the northern boreal forest of interior Alaska, USA. We used multistate capture-mark-recapture models to estimate adult survival, breeding probability, first-year survival, and recruitment probability using a long-term nest box study (1997-2010). We detected annual variation in adult survival, which varied from 0.74 +/-. 0.12 (SE) to 0.93 +/-. 0.06. In contrast, breeding probability remained relatively high and invariant (0.84 +/- 0.11) and was positively related to individual nest success the year prior. Nonbreeding individuals in one year were more likely to remain a nonbreeder, than attempt to breed the following year. First-year survival decreased with smaller residual duckling mass and larger brood sizes. Probability of recruitment into the breeding population conditioned on survival was constant during the study (0.96 +/- 0.06), and did not vary among ages 2-5 yr-old. Overall, goldeneyes exhibited high, but somewhat variable, adult survival, and high breeding and recruitment probabilities, which is consistent with observed patterns in bet-hedging species that breed annually in high quality breeding environments, but whose reproductive output is often influenced by stochastic events. Demographic estimates from this study are among the first for goldeneyes within Alaska. Life history patterns are known to vary geographically, therefore, we recommend further examination of life history patterns within the distribution of goldeneyes.
Times Cited in Web of Science Core Collection: 7 Total Times Cited: 7 Cited Reference Count: 85
Keywords: SURVIVAL; POPULATION-DYNAMICS; SOMATERIA-MOLLISSIMA; BUCEPHALA-CLANGULA; NATAL PHILOPATRY; EGG SIZE; BARROWS GOLDENEYES; BRANTA-BERNICLA-NIGRICANS; FUTURE REPRODUCTION; NEST BOXES

Mate guarding conflict, extra-pair courtship and signalling in the harlequin duck, Histrionicus histrionicus - Lazarus, John; Inglis, Ian R.; Torrance, Rebecca L. L. F. (Behaviour, 2004)
Socially monogamous birds pursuing extra-pair reproductive strategies may be in conflict, both sexes seeking new mates or copulations outside the pair, while simultaneously attempting to prevent infidelity by the partner. Intra-pair conflicts are augmented by inter-pair conflicts when pairs meet, when all four individuals may be sexually attracted to one member of the other pair while seeking to prevent their mate from copulating, or deserting, with the other. We studied the dynamics, signalling and resolution of these conflicts in a field experiment with the harlequin duck, recording responses to single model birds of both sexes, and to model pairs. Both sexes mate guarded by placing themselves between the mate and a model competitor, and by signalling with the head nod display. Females were closer to model pairs than their mates. Female mate guarding responded adaptively to infidelity risk, increasing to models of paired females, single females and single females inviting copulation, respectively. Males head nodded to signal the goal of (extra-pair) copulation, pairing or mate switching. Courtship by unpaired males increased to models of paired females, single females and single females inviting copulation, respectively. Paired males courted these models equally, perhaps inhibited by the parallel increase in mate guarding of their mates. Males signalled mate guarding using the head nod more than females, but this predicted difference in mate guarding was not shown for the measure of relative proximity to the models. In spite of male extra-pair courtship the harlequin is strictly monogamous, due to female fidelity and close mate guarding. The use of models revealed mate guarding by females, and failed extra-pair reproductive attempts by males, neither of which were apparent from observational studies alone.
Keywords: Behavior; Breeding Season; Harlequin duck; Histrionicus histrionicus

INTRANASAL ADMINISTRATION OF MIDAZOLAM HYDROCHLORIDE IMPROVES SURVIVAL IN FEMALE SURF SCOTERS (MELANITTA PERSPICILLATA) SURGICALLY IMPLANTED WITH INTRACOELOMIC TRANSMITTERS - Le Net, R.; Mulcahy, D. M.; Santamaria-Bouvier, A.; Gilliland, S. G.; Bowman, T. D.; Lepage, C.; Lair, S. (JOURNAL OF ZOO AND WILDLIFE MEDICINE, 2019)
The intracoelomic implantation of satellite transmitters is associated with lower survival in surf scoters (Melanitta perspicillata) comparcd with other species of diving ducks, potentially due to physiologic alterations following physical exertion and stress caused by handling and confinement. The effect of intranasal administration of midazolam hydrochloride on survival of surf scoters surgically implanted with intracelomic transmitters was evaluated. Shortly after their capture in Forestville (QC, Canada) in the fall of 2013, 26 randomly selected adult female surf scoters were administered midazolam hydrochloride (4.6-5.9 mg/kg) intranasally. The same volume of saline (1 mL) was given to another 26 adult female surf scoters as a control group. All birds were surgically implanted with an intracoelomic transmitter equipped with a percutaneous antenna. Transmitters were programmed to transmit 2 hr each day for 30 days after implantation, and mortality was estimated for each group using the telemetry data. The association between the administration of midazolam and survival was assessed while controlling for other factors such as body mass, transmitter-mass-to-body-mass ratio, hematocrit, total solids, and duration of surgery, anesthesia, and confinement. The odds of presumed death in the saline group were 5.3 times higher than in the midazolam group (95% confidence interval: 1.7, 19.0; P = 0.004). The presumed mortality at 30 days for the midazolam group (23%) was lower than for the saline group (61%). No other variable was significantly associated with survival. These results suggest that sedation with midazolam shortly after capture increased the postsurgical survival of female surf scoters surgically implanted with intracoelomic transmitters.
Times Cited in Web of Science Core Collection: 4 Total Times Cited: 4 Cited Reference Count: 51
Keywords: Melanitta perspicillata; Satellite telemetry; WILD; Surf scoter; RADIO TRANSMITTERS; PERFORMANCE; ANIMALS; Avian sedation; CAPTURE; Intracoelomic transmitter; LIMOSA-LAPPONICA; Midazolam; SATELLITE TRANSMITTERS; SEDATION; XYLAZINE

Body mass and carcass composition of fall migrant Oldsquaws - Leafloor, James O.; Thompson, John E.; Ankney, C. Davison (Wilson Bulletin, 1996)
We investigated body and organ mass and carcass composition of twenty-seven migrant Oldsquaws (Clangula hyemalis) killed when they collided with power transmission lines in northeastern Ontario in October 1986. Comparison of the first principal component (PC1) from eight structural measurements indicated that adult male Oldsquaws were structurally larger than females; however, organ weights did not differ between sexes when PC1 was included as a covariate (ANCOVA, P gt 0.05 in all cases). Carcass composition was similar to that reported for spring migrants. Ash-free lean dry weight (AFLDW) and ash were positively related to structural size, but did not differ between sexes when PC1 was included as a covariate. Lipids comprised 17.5 % of whole body mass of females and 14.1% of males and were sufficient to fuel migration at least to the next likely staging area in the Great Lakes. Fall migrant Oldsquaws must have stored substantial lipid and protein reserves after breeding, suggesting that offshore feeding areas in James and Hudson Bay are critical.
Keywords: Nonbreeding Seasons; Clangula hyemalis; Long-tailed Duck; Migration; Energetics and Nutrition

Nematodes in the mallard (Anas platyrhynchos Linnaeus, 1758) and the common goldeneye (Bucephala clangula Linnaeus, 1758) (Anatidae) from Northern Europe - Lebedeva, D. I.; Yakovleva, G. A.; Ieshko, E. P. (Parasitology Research, 2015)
There are first data on nematodes of Anas platyrhynchos Linnaeus, 1758 (mallard) and Bucephala clangula Linnaeus, 1758 (common goldeneye) from Northern Europe (Ladoga Lake region). The ducks were found to be infected with nine nematode species. A. platyrhynchos hosted eight nematode species and B. clangula was host to four nematode species. All species except Capillaria anatis were found in the region for the first time. Nematodes Amidostomum acutum, Streptocara crassicauda, and Tetrameres fissispina parasitized on both hosts and were the most abundant. The biggest number of parasites revealed was biohelminths with a direct life cycle.
Lebedeva, Daria I. Yakovleva, Galina A. Ieshko, Evgeny P.
Keywords: Bucephala clangula; Common Goldeneye; Parasites

Fish and harlequin ducks compete on breeding streams - LeBourdais, S. V.; Ydenberg, R. C.; Esler, D. (Canadian Journal of Zoology, 2009)
We investigated interactions among harlequin ducks (Histrionicus histrionicus ( L., 1758)), fish, and their shared aquatic insect prey. We measured flow variability, benthic aquatic prey abundance, fish presence, and breeding density of harlequins on eight rivers in the Southern Coast Mountain Range in British Columbia, Canada, in 2003 and 2004. Rivers with lower flow variability had higher abundance of aquatic insects. Densities of harlequins and fish presence on the rivers were both significantly and positively related to insect abundance, but path analysis revealed a strong negative correlation between them. We interpret this as an indirect interaction between harlequins and fish mediated by anti-predator behaviour of insects in the presence of fish, which reduces insect availability, rather than as a reduction in the abundance of aquatic insects through consumption by fishes. We hypothesize that the ongoing and widespread introduction of fish into historically fishless waters throughout North America may have contributed to the current low productivity and recruitment measured in populations of harlequins by reducing quality of breeding habitat.
Keywords: Breeding Season; Harlequin duck; Histrionicus histrionicus; Trophic Interactions

The mitochondrial genome of the goosander (Mergus merganser) determined using next-generation sequencing - Lee, S. M.; Jeon, H. S.; Kim, J. A.; Kim, J.; Park, J.; Kil, H. J. (MITOCHONDRIAL DNA PART B-RESOURCES, 2019)
We report here the complete mitochondrial genome of Mergus merganser, which was determined using Illumina next-generation sequencing. The complete mitogenome is 16,631 bp, with 13 protein-coding genes, 22 transfer RNA genes, and 2 ribosomal RNA genes. The order and structure of the genes are similar to those of other Anatinae species. The overall base composition of the mitogenome is 28.7% (A), 21.8% (T), 16.0% (G), and 33.2% (C), with AT contents of 50.7%. Phylogenetic analysis based on 13 concatenated PCG sequences indicated that M. merganser is closely related to M. squamatus (HQ833701 and NC016723) with high bootstrap values (100%).
Times Cited in Web of Science Core Collection: 0 Total Times Cited: 0 Cited Reference Count: 9
Keywords: Common merganser; ANNOTATION; goosander; mitochondrial genome; next generation sequencing

No selection on immunological markers in response to a highly virulent pathogen in an Arctic breeding bird - Legagneux, P.; Berzins, L. L.; Forbes, M.; Harms, N. J.; Hennin, H. L.; Bourgeon, S.; Gilchrist, H. G.; Bety, J.; Soos, C.; Love, O. P.; Foster, J. T.; Descamps, S.; et al. (Evolutionary Applications, 2014)
In natural populations, epidemics provide opportunities to look for intense natural selection on genes coding for life history and immune or other physiological traits. If the populations being considered are of management or conservation concern, then identifying the traits under selection (or markers') might provide insights into possible intervention strategies during epidemics. We assessed potential for selection on multiple immune and life history traits of Arctic breeding common eiders (Somateria mollissima) during annual avian cholera outbreaks (summers of 2006, 2007 & 2008). We measured prelaying body condition, immune traits, and subsequent reproductive investment (i.e., clutch size) and survival of female common eiders and whether they were infected with Pasteurella multocida, the causative agent of avian cholera. We found no clear and consistent evidence of directional selection on immune traits; however, infected birds had higher levels of haptoglobin than uninfected birds. Also, females that laid larger clutches had slightly lower immune responses during the prelaying period reflecting possible downregulation of the immune system to support higher costs of reproduction. This supports a recent study indicating that birds investing in larger clutches were more likely to die from avian cholera and points to a possible management option to maximize female survival during outbreaks.
Legagneux, Pierre Berzins, Lisha L. Forbes, Mark Harms, Naomi Jane Hennin, Holly L. Bourgeon, Sophie Gilchrist, H. G. Bety, Joel Soos, Catherine Love, Oliver P. Foster, Jeffrey T. Descamps, Sebastien Burness, Gary Si
Keywords: Behavior; Breeding Season; Common Eider; Somateria mollissima; Productivity; Disease

Delayed autumn migration in northern European waterfowl - Lehikoinen, A.; Jaatinen, K. (Journal of Ornithology, 2012)
Times Cited: 6 Lehikoinen, Aleksi Jaatinen, Kim Jaatinen, Kim/A-3221-2011 7
Keywords: migration; Nonbreeding Seasons; Somateria mollissima; Common eider

Rapid climate driven shifts in wintering distributions of three common waterbird species - Lehikoinen, A.; Jaatinen, K.; Vahatalo, A. V.; Clausen, P.; Crowe, O.; Deceuninckk, B.; Hearn, R.; Holt, C. A.; Hornman, M.; Keller, V.; Nilsson, L.; Langendoen, T.; et al. (Global Change Biology, 2013)
Times Cited: 0 Lehikoinen, Aleksi Jaatinen, Kim Vahatalo, Anssi V. Clausen, Preben Crowe, Olivia Deceuninckk, Bernard Hearn, Richard Holt, Chas A. Hornman, Menno Keller, Verena Nilsson, Leif Langendoen, Tom Tomankova, Irena Wahl, Johannes Fox, Anthony D. Fox, Anthony/I-7465-2013; Jaatinen, Kim/A-3221-2011; Clausen, Preben/J-5276-2013 0
Keywords: Abundance, Distribution, and Trends; Nonbreeding Seasons; Somateria mollissima; Common eider

Does Sex-Specific Duckling Mortality Contribute to Male Bias in Adult Common Eiders? - Lehikoinen, Aleksi; Ost, Markus; Hollmen, Tuula; Kilpi, Mikael (Condor, 2008)
Adult sex ratios of waterfowl often show male bias, usually explained by differential female mortality during breeding. However, the sex ratio among first-winter Common Eiders (Somateria mollissima) in Europe is already male biased; thus, the breeding mortality hypothesis cannot be the sole explanation for this phenomenon. To clarify when the observed male bias originally arises, we studied the sex ratio of hatched eider ducklings and the sex ratio of ducklings found dead prior to fledging in a wild and free-ranging population. The hatching sex ratio did not deviate from equal (50% females, n = 418). In contrast, the sex ratio of duckling carcasses was female biased (59%, n = 118), suggesting that survival of female ducklings is lower than that of males. Consequently, the adult-male bias found in many ducks may be established already during the early phases of life, despite an equal sex ratio at hatching.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Productivity; Survival

Rolling Flock Movement of Foraging Long-Tailed Ducks Clangula-Hyemalis - Leipe, T.; Scabell, J. (Vogelwelt, 1990)
A special behaviour of Long-tailed Ducks in large flocks enables them to investigate unknown submarine food resources in a highly efficient way. The foraging formation moves like a roll in a fixed direction. The ducks at the back of the flock continuously fly to the front of the searching formation and dive to the sea bottom. When a profitable food patch had been located, the rolling movement comes to a halt and the ducks concentrate over the foot patch. During several winters we observed such behaviour in the Greifswalder Boden area of the southwestern Baltic Sea coast. Here Long-tailed Ducks exploit especially fresh deposits of herring spawn. The rate of sea bottom search by a flock of ca. 5000 individuals can reach up to 60-80 hectars per hour.
Keywords: Behavior; Nonbreeding Seasons; Clangula hyemalis; Long-tailed Duck

Wetland Use and Selection by Breeding Waterbirds in the Boreal Forest of Quebec, Canada - Lemelin, Louis-Vincent; Darveau, Marcel; Imbeau, Louis; Bordage, Daniel (Wetlands, 2010)
Wetlands of remote forested landscapes of Quebec support numerous species of breeding waterbirds yet species-habitat associations remain poorly quantified. From 1990 to 2005, we conducted systematic helicopter surveys of breeding waterfowl and common loons (Gavia immer) across a 540,000-km(2) forested region of Quebec. Data from this survey were used to investigate local habitat use and selection by waterbirds, based on a wetland classification system derived from digital forestry maps. Detailed indicated-breeding-pair (IBP) distributions were developed for broad aquatic, wetland, and shoreline habitat types. We also estimated selection ratios within groups of similar habitat types. Small (<= 8 ha), connected ponds were highly used and selected by five dabbling duck species and by wood duck (Aix sponsa), Canada goose (Branta canadensis), ring-necked duck (Aythya collaris), hooded merganser (Lophodytes cucullatus), common goldeneye (Bucephala clangula), and Barrow's goldeneye (B. islandica). Dabbling duck species, wood duck, and Canada goose made extensive use of streams (25-41% of all IBP). Community organization was mainly driven by openness of aquatic habitat and water movement, i.e., from lentic to lotic habitats. Failure to include streams in waterfowl surveys and habitat mapping could produce biased estimates of wetland habitat use and selection in the boreal forest.
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Habitat; Hooded Merganser; Lophodytes cucullatus; Barrow's Goldeneye; Bucephala islandica

Common Scoters Melanitta nigra in The Netherlands - Leopold, Mardik; Baptist, Henk; Wolf, Pim; Offringa, Henk (Limosa, 1995)
The Common Scoter has long been known as a common migrant and winter visitor along the Dutch coast. Good estimates of numbers staging in Dutch waters were lacking however, due to the elusive habits of the species. From incidental records gleaned from literature, its status in the past was reconstructed. At the turn of the century the species was a "very common" bird along the coast, but quantitative data are lacking. In the first half of this century groups of tens of thousands of birds were seen migrating or swimming on several occasions, and the species commonly washed up as oil-victim, indicating common and widespread occurrence in coastal waters. In the 1960's the first aerial and ship surveys were carried out in the Wadden Sea area. These indicated that some 40 000 Common Scoters wintered in the western Wadden Sea. Moreover, there were several sightings of large ( gt 10 000) groups in the adjacent North Sea. In the 1970's, surveys in the Wadden Sea showed that numbers of wintering scorers had declined to a maximum of 8000. In the Delta area, where numbers of ducks were monitored by plane from 1975 onward, some 15-25 000 birds wintered in the 1970's and early 1980's. In those years there were few surveys along the coasts of the Dutch mainland and the Frisian Islands and most information comes from seawatching sites. Records of groups of 5000 or more were rare, and only in 1978 around 10 000 were recorded at one site (Tab. 1 and 2). From 1985 onward, the whole Dutch coast was surveyed by plane, and shipboard surveys were carried out in 1989-93. In the Delta area, large numbers (c. 20 000) returned in the winters of 1986-88 after a low in the early 1980's (Fig. 1), but numbers declined again after a large land reclamation project was carried out in the ducks' favourite area. Off mainland Holland numbers were generally low, but in the winter of 1986/87 about 60 000 Common Scoters were found wintering here. The coastal waters north of the Frisian Islands became the most important area in the early 1990's (Fig. 2). In 1989/90 c. 10 000 Common Scorers wintered near Schiermonnikoog, and in the winters of 1990-93, 100-135 000 wintered in this area, at first off Schiermonnikoog and later off Terschelling. Numbers that remain in Dutch waters in summer are less well documented. After an old record (1888) of uncountable numbers moulting in the Wadden Sea near Schiermonnikoog, moulting birds were not seen in any numbers for over 100 years. In the 1970's moulted feathers were found "in considerable numbers" at Schiermonnikoog, but moulting ducks were not seen. Only in 1991 groups of moulting Common Scoters were found: 550 in the Delta area and c. 11 000 and 250 in the North Sea off Terschelling and Rottum, respectively. Therefore, Common Scoters should be considered as (moulting) summering birds in rather large numbers in The Netherlands, at least in some years. A rich supply of the clam Spisula subtruncata was present at all locations where the scoters wintered in large numbers since 1987, and this bivalve is now the most important food items for the ducks. From 1992 to 1994 this food source also attracted Dutch shellfishermen. Their activities disturbed the ducks and drove them away from their favourite site off Terschelling. This branch of fishery is ill-regulated, and it seems capable of destroying the ducks' feeding grounds. A set of regulations, by which shellfishery in the areas where the ducks winter in a given year is closed, is recommended. Other improvements of the management of seaducks in The Netherlands would include specific vigilance for oil pollution in areas with concentrations of seaducks.
Keywords: Abundance, Distribution, and Trends; Nonbreeding Seasons; Black Scoter; Melanitta nigra

Status of Quebec waterfowl populations, 2009 - Lepage, C.; Bordage, D. (Technical Report Series, 2013)
Status of Quebec Waterfowl Populations, 2009 is intended to provide an up-to-date picture of the status of waterfowl species in Quebec. This publication has for each of the 37 species annually present (as a breeder, a migrant or a winterer) in the province a text that provides an overview of seasonal occurrence, an assessment of provincial and continental population trends, a description of conservation issues, and the importance of the role played by Quebec in its conservation. The Anserini tribe (geese) includes six species that are observed regularly in Quebec. However, the only common breeder is the Canada Goose, which is also an abundant migrant. During migration, while the Snow Goose (Greater subspecies) and Brant pass in large numbers, the Greater White-fronted Goose, Ross’s Goose, Snow Goose (Lesser subspecies) and Cackling Goose are more observed in small numbers. The tribe Cygnini (swans) is represented by two species that breed in Quebec, but only the Tundra Swan is a regular breeder. The Mute Swan, despite an extraordinary breeding record, is mainly observed irregularly and in small numbers. The tribe Anatini (dabbling ducks) includes nine species that are regular breeders in Quebec. While most of the species in this tribe are originally Prairie natives (Gadwall, American Wigeon, Mallard, Blue-winged Teal, Northern Shoveler and Northern Pintail), the American Black Duck, Wood Duck and Green-winged Teal are intimately linked to forest habitats. The American Black Duck breeds exclusively in northeastern North America. The Aythyini tribe (diving ducks) is composed of five species regularly observed in Quebec. Mostly associated with the Prairies, the Canvasback (migrant only) and Redhead are present only in small numbers in the province. While the Greater Scaup and Lesser Scaup breed mainly in the northern half of Quebec, the Ring-necked Duck has a fairly continuous and uniform distribution in Quebec, and is therefore present in large numbers. The tribe Mergini (sea ducks) is represented by 13 species that breed regularly in Quebec, with a number of them present even in winter. This is a highly variable group generally associated with marine environments during a sizeable portion of their annual cycle. The Surf Scoter, Bufflehead, Common Goldeneye, Barrow’s Goldeneye, Hooded Merganser and Common Merganser prefer the boreal forest. The King Eider, Harlequin Duck, White-winged Scoter, Black Scoter, Long-tailed Duck and Red-breasted Merganser inhabit primarily the taiga or tundra, and the Common Eider breeds in colonies in island and coastal environments. Two species of Mergini are considered of special concern on the List of Wildlife Species at Risk in Canada: Harlequin Duck (Eastern Population) and Barrow’s Goldeneye (Eastern Population). Lastly, the tribe Oxyurini (stiff-tailed ducks) includes only one species breeding in Quebec, the Ruddy Duck. The waterfowl species for which Quebec has an important responsibility—based on the Quebec proportion of breeding or migrant numbers compared to North American numbers—are the following: Snow Goose (Greater subspecies), Brant (Atlantic Population), Canada Goose (Atlantic and North Atlantic populations), American Black Duck, Common Eider (dresseri and borealis subspecies), Harlequin Duck (Eastern Population), Black Scoter, Barrow’s Goldeneye (Eastern Population), Hooded Merganser, Common Merganser and Red-breasted Merganser.
Keywords: Common Eider; Melanitta fusca; White-winged Scoter; Melanitta perspicillata; Surf Scoter; Histrionicus histrionicus; Clangula hyemalis; Long-tailed Duck; Bucephala clangula; Common Goldeneye; Somateria mollissima; King Eider; Somateria spectabilis; Mergus merganser; Mergus serrator; Bucephala albeola; Bufflehead; Black Scoter; Hooded Merganser; Lophodytes cucullatus; Bucephala islandica; Abundance, Distribution, & Trends; Barrow’s Goldeneye; Common Merganser; Melanitta americana; Red-breasted Merganser; Harlequin Duck

Spatial Ecology of White-winged Scoters (Melanitta deglandi) in Eastern North America: A Multi-year Perspective - Lepage, C.; Savard, J. P. L.; Gilliland, S. G. (WATERBIRDS, 2020)
Satellite transmitters were used to describe migration patterns and establish connectivity among breeding and wintering areas for 30 White-winged Scoters (Melanitta deglandi) tagged in August 2010 or August 2012 during remigial molt in the St. Lawrence Estuary, Quebec, Canada. Fourteen potential breeding sites were identified in the boreal forest from Quebec to the Northwest Territories, Canada. Most birds molted at marine sites, except for two females that molted close to their breeding areas and a male that molted in interior Manitoba. Most birds remained near their molting location during fall prior to migrating to their wintering area. Individuals tended to use similar fall migration routes from year to year. Most birds (81%) wintered in the Long Island-Nantucket-Cape Cod region along the eastern seaboard of the USA, while only three birds wintered in Canada. Scoters spent almost half the year on wintering areas, and 83% returned within 150 km of the previous year's site. Spring migration patterns depended on breeding status. Breeding birds covered an average of 6,880 km compared to 2,550 km by non-breeding birds during their annual cycle. The St. Lawrence Estuary in Quebec and the Long Island-Nantucket-Cape Cod region (New York state and Massachusetts) were areas particularly important for tagged birds.
Times Cited in Web of Science Core Collection: 3 Total Times Cited: 3 Cited Reference Count: 71
Keywords: White-winged Scoter; satellite telemetry; site fidelity; SURF SCOTERS; SPP.; EIDERS; PACIFIC COAST; MIGRATION; MOLT; spring migration; wintering; BLACK SCOTERS; breeding; CHRONOLOGY; fall migration; key sites; Melanitta deglandi; PERSPICILLATA; staging

Plumage developement and growth of wild Surf Scoter Melanitta perspicillata ducklings - Lesage, Louis; Reed, Austin; Savard, Jean-Pierre L. (Wildfowl, 1996)
The plumage development and growth of wild Surf Scoter ducklings were studied in a 640 ha boreal forest lake in Quebec by observing and photographing free-ranging individuals and by examining live-caught birds. During their first three to five days, Surf Scoter ducklings were uniformly dark with few distinctive markings. Subsequently, the appearance of a pale-coloured cheek patch added some contrast to their pattern but they remained generally undistinctive through to fledging, at which time they were quite similar in size, appearance and colouration to the female parent. Subtle differences in the shape, size and colouration of the cheek patch, and neck posture (head held close to body or erect), were useful clues to distinguish age classes in the field. Body mass increased from about 44 to 817 g during the 55-day period between hatching and fledging, whereas head length increased from 41 to 97 mm. Few differences in plumage development or growth pattern were noted from studies of other duck species.
Keywords: Breeding Season; Melanitta perspicillata; Surf Scoter; Physiology

Duckling survival and use of space by surf scoter (Melanitta perspicillata) broods - Lesage, Louis; Reed, Austin; Savard, Jean-Pierre L. (Ecoscience, 2008)
Knowledge of many aspects of the breeding ecology of surf scoters (Melanitta perspicillata) is still lacking, partly due to the remoteness of the boreal forest regions where they commonly breed. Documentation of duckling survival and use of space by broods is important in understanding population dynamics and habitat requirements of waterfowl. These aspects were documented at Lake Malbaie (Quebec, Canada) in 1994 and 1995. Duckling mortality was estimated at 65% in 1994 and 55% in 1995 and was probably influenced by weather conditions shortly after hatch. Females with broods showed a strong preference for portions of the lake with water depths < 2 m and where islands or wooded shorelines offered protection from dominant winds; both of these factors reduced wave amplitude, which may have facilitated food acquisition for ducklings. Home ranges of 7 broods accompanied by marked females varied in size from 28 to 173 ha (mean 94.5 +/- 7.5 ha).
Keywords: Breeding Season; Melanitta perspicillata; Surf Scoter; Survival; Habitat

A simple technique to capture breeding adults and broods of surf scoters, Melanitta perspicillata - Lesage, Louis; Savard, Jean-Pierre L.; Reed, Austin (Canadian Field-Naturalist, 1997)
We used mist nets strung above and below the water surface to capture pairs prior to and during nest initiation, and to capture ducklings during brood-rearing. We discuss possible modifications of this technique to improve its effectiveness for capturing Surf Scoters and other diving ducks.
Keywords: Breeding Season; Melanitta perspicillata; Surf Scoter; Techniques

The Occurrence of Scaup Aythya-Marila Eider Somateria-Mollissima Long-Tailed Duck Clangula-Hyemalis Common Scoter Melanitta-Nigra Velvet Scoter Melanitta-Fusca in Inland Areas in Poland - Lewartowski, Z.; Stawarczyk, T.; Winiecki, A. (Acta Ornithologica (Warsaw), 1986)
The analysis of the occurrence of five sea duck species in inland areas in Poland is based mainly on data on their visits, gathered in the seasons 1945/46 to 1982/83. It has been found that velvet scoters occurred most frequently (267 sightings), followed by scaups (262), while long-tailed ducks (127) and common scoters (123) were clearly less frequent, eiders being the least frequent of them all (47 appearances). All these species visited areas in Poland, except high mountains, the largest number of occurrences having been recorded for Wielkopolska and Silesia (about 65% jointly). In some seasons the appearance of some of the species, especially of the velvet scoter and common scoter, was of the nature of invasion. Four species occurred most frequently and abundantly in autumn, and their peak numbers were recorded most frequently in November. Their wintering, spring and summer visits were much less frequent. The eider occurred equally frequently and in equal numbers in different months, being relatively numerous also in May and June. Inland regions were penetrated most frequently by single individuals or small flocks of several birds each, most of which were individuals in female plumage (68-92%), exept eiders, the males of which were more frequently encountered (64%). Visiting birds stayed most often on lakes and large rivers, slightly less often on dam reservoirs, and rather rarely on ponds. The main factor causing visits of sea ducks in inland regions of Poland was storms on the southern Baltic, most frequent in autumn and winter months.
Keywords: Abundance, Distribution, and Trends; Melanitta fusca; Nonbreeding Seasons; White-winged Scoter

Effects of predation by sea ducks on clam abundance in soft-bottom intertidal habitats - Lewis, Tyler L.; Esler, Daniel; Boyd, W. Sean (Marine Ecology Progress Series, 2007)
Recent studies have documented strong, top-down predation effects of sea ducks on mussel populations in rocky intertidal communities. However, the impact of these gregarious predators in soft-bottom communities has been largely unexplored. We evaluated effects of predation by wintering surf scoters Melanitta perspicillata and white-winged scoters M, fusca on clam populations in soft-bottom intertidal habitats of the Strait of Georgia, British Columbia. Specifically, we documented spatial and temporal variation in clam density (clams m(-2)), scoter diet composition, and the consequences of scoter predation on clam abundance. Of the 3 most numerous clams, Manila clams Venerupis philippinarum and varnish clams Nuttallia obscurata were the primary prey items of both scoter species, while clams of the genus Macoma were rarely consumed by scoters. Between scoter arrival in the fall and departure in the spring, Manila clams decreased in density at most sample sites, while varnish clam densities did not change or declined slightly. Our estimates of numbers of clams consumed by scoters accounted for most of the observed declines in combined abundance of Manila and varnish clams, despite the presence of numerous other vertebrate and invertebrate species known to consume clams. For Macoma spp., we detected an over-winter increase in density, presumably due to growth of clams too small to be retained by our sieve (< 5 mm) during fall sampling, in addition to the lack of predation pressure by scoters. These results illustrate the strong predation potential of scoters in soft-bottom intertidal habitats, as well as their potentially important role in shaping community structure.
Keywords: Melanitta fusca; Nonbreeding Seasons; White-winged Scoter; Melanitta perspicillata; Surf Scoter; Trophic Interactions

Foraging behaviors of Surf Scoters and White-winged Scoters during spawning of Pacific herring - Lewis, Tyler L.; Esler, Daniel; Boyd, W. Sean (Condor, 2007)
Winter diets of Surf (Melanitta perspicillata) and White-winged Scoters (M. fusca) are composed primarily of bivalves. During spawning of Pacific herring (Clupea pallasi) in early spring, scoters shift their diets to herring eggs. Using radiotelemetry, we contrasted scoter foraging behaviors between winter and herring spawning periods. Scoters increased their dive durations during herring spawning, likely to maximize the amount of roe consumed per dive; in winter, dives were typically terminated upon clam capture. Scoters spent approximately 5011,, less time foraging (min underwater hr(-1)) and decreased their dive rate (dives hr(-1)) by 70% when feeding on roe. The observed reduction in time spent foraging was presumably caused by the abundance of herring eggs, and thus a reduction in prey search-time. Scoters were able to meet energetic requirements with reduced effort, despite potentially increased demands related to spring fattening. Less time spent foraging may also allow more time for premigratory courtship behaviors.
Keywords: Behavior; Melanitta fusca; Nonbreeding Seasons; White-winged Scoter; Melanitta perspicillata; Surf Scoter; Trophic Interactions

Foraging behavior of Surf Scoters (Melanitta perspicillata) and White-winged Scoters (M-fusca) in relation to clam density: Inferring food availability and habitat quality - Lewis, Tyler L.; Esler, Daniel; Boyd, W. Sean (Auk, 2008)
Birds are known to modify their foraging behavior in relation to food availability. Once understood, these relationships can be used to draw inferences about relative food availability and habitat quality. We measured foraging behavior of Surf Scoters (Melanitta perspicillata) and White-winged Scoters (M. fusca) feeding on clams during winter in the Strait of Georgia, British Columbia, to evaluate the relative quality of the foraging landscape for wintering scoters. Because clam biomass does not increase appreciably during winter through growth or recruitment, scoters are faced with a depleting and potentially exhaustible food supply. Along with this temporal variation, clam densities vary widely by site. We considered the influence of variation in clam density on scoter foraging behavior, along with other factors known to affect foraging in other sea duck species, such as season, sex, age, and environmental attributes. Clam-capture success (clams captured per dive) and foraging effort (minutes underwater per hour) of Surf Scoters were not related to variation in clam density. Clam-capture success of White-winged Scoters was unrelated to clam density; however, their foraging effort was negatively related to clam density, though varying by only 4 min across the range of observed clam densities. For both species, foraging behavior was generally more strongly related to other factors, especially seasonal and age effects. These results suggest that (1) observed variation in clam density was relatively minor from the perspective of foraging scorers and (2) our study site constituted high-quality winter habitat in which scoters were not constrained by food availability.
Keywords: Behavior; Melanitta fusca; Nonbreeding Seasons; White-winged Scoter; Melanitta perspicillata; Surf Scoter; Trophic Interactions; Habitat

Nocturnal foraging behavior of wintering surf scoters and White-winged Scoters - Lewis, Tyler L.; Esler, Daniel; Boyd, W. Sean; Zydelis, Ramunas (Condor, 2005)
We studied the nocturnal foraging behavior of Surf Scoters (Melanitta perspicillata) and White-winged Scoters (Melanitta fusca) during winter in coastal British Columbia, Canada. Using radio telemetry, we collected nocturnal and diurnal data documenting the frequency of foraging dives and the location of scoters in relation to their intertidal foraging grounds. We found that dive foraging rarely occurred during nocturnal periods for either species. Only 2% of nocturnal observation blocks for both scoter species contained diving, compared with 98% of diurnal observation blocks. This corresponded to an average of only 0.1 min spent underwater per half-hour observation block during the night and over 7 min during the day. Both species of scoters were located farther offshore and in deeper waters during nocturnal hours, indicating that they were not using intertidal foraging areas at night. Our results suggest that Surf Scoters and White-winged Scoters face daylight-imposed limits on the amount of available foraging time. These potential day-length restrictions should be considered when reviewing human activities that potentially alter the amount of available foraging time or food supplies in winter habitats.
Keywords: Behavior; Melanitta fusca; Nonbreeding Seasons; White-winged Scoter; Melanitta perspicillata; Surf Scoter

Reliability of External Characteristics to Age Barrow's Goldeneye - Lewis, T. L.; Esler, D.; Hogan, D. H.; Boyd, W. S.; Bowman, T. D.; Thompson, J. (WILDLIFE SOCIETY BULLETIN, 2020)
Accurate assignment of age class is critical for understanding most demographic processes. For waterfowl, most techniques for determining age class require birds in hand, reducing utility for quickly and efficiently sampling a large portion of the population. As an alternative, we sought to establish an observation-based methodology, achievable in the field with standard optics, for determining age class of Barrow's goldeneyes (Bucephala islandica). We photographed heads, wings, and bellies of 232 Barrow's goldeneyes captured during late winter (February-April) of 2007-2015 along the north Pacific Coast. From these photographs, we focused on 5 external characteristics for both males and females, with binary states that putatively corresponded to 2 age classes-first-year birds (<1 yr) and adults (>1 yr). For males, all 5 external traits (belly color, head color, eye color, facial crescent, median secondary coverts color) had binary states that were reliably distinguishable by observers. Moreover, all 5 external traits were highly predictive of age class (>= 96% concordance between external vs. bursal-derived ages), and novice observers, after receiving training, were able to accurately age 96% of first-year and 99% of adult males. In contrast, patterns were weaker for females; putative external characteristics of female age class (belly color, bill radiance, bill blackness, eye color, median secondary coverts color) had 77-91% concordance with bursal-derived age, compared with 96-100% for males, and observers misidentified age classes of 15% of females, compared with only 2% of males. Overall, age classes of male Barrow's goldeneyes were accurately and reliably distinguishable during winter based on several external characteristics, whereas those of females were not. Our technique may be used to estimate age composition of male Barrow's goldeneyes during winter, providing a useful metric for monitoring annual changes in adult-to-juvenile ratios and other important demographic parameters. (c) 2020 The Wildlife Society.
Times Cited in Web of Science Core Collection: 1 Total Times Cited: 1 Cited Reference Count: 22
Keywords: DUCKS; SURVIVAL; Bucephala islandica; sea duck; age class; age ratio; Barrow's goldeneye; bursa; INDICATOR; plumage; RECRUITMENT; SEX; sex determination

Attaching Transmitters to Waterbirds Using One Versus Two Subcutaneous Anchors: Retention and Survival Trade-Offs - Lewis, T. L.; Esler, D.; Uher-Koch, B. D.; Dickson, R. D.; Anderson, E. M.; Evenson, J. R.; Hupp, J. W.; Flint, P. L. (WILDLIFE SOCIETY BULLETIN, 2017)
A major challenge of wildlife telemetry is choosing an attachment technique that maximizes transmitter retention while minimizing negative side effects. For waterbirds, attachment of transmitters with subcutaneous anchors has been an effective and well-established technique, having been used on >40 species. This method was recently modified to include a second subcutaneous anchor, presumably increasing transmitter retention beyond that of single-anchor attachments. This putative benefit may be offset, however, by increased health risks related to additional incisions and subcutaneous protrusions. To test this potential trade-off, we attached radiotransmitters to molting and wintering surf (Melanitta perspicillata) and white-winged scoters (M. fusca) during 2008 and 2009 in Washington State and southeast Alaska, USA, using single- (121 scoters) and double-anchor (128 scoters) attachment techniques. We estimated daily probabilities of survival and radio retention for each group, this being apparent retention for wintering scoters because we could not differentiate shed transmitters from flighted emigration. For scoters during the flightless remigial molt, we found that addition of a second anchor increased cumulative retention probability (SE) over a 49-day period from 0.69 +/- 0.11 for single-anchor to 0.88 +/- 0.07 for double-anchor attachments, while having no effect on survival. However, during winter, scoters with double-anchor attachments experienced no improvement in apparent retention, while having significantly lower survival during their first 14 days following transmitter attachment; of 15 mortalities during this period, 11 had 2 subcutaneous anchors. From day 15 onward, winter survival rates were nearly identical for single- versus double-anchor attachments, indicating that adverse effects of subcutaneous anchors were mainly limited to the 14-day postattachment period. Overall, given that the survival cost of adding a second subcutaneous anchor was substantial for wintering scotersdecreasing 14-day survival by 12% for adults and 23% for juvenileswe recommend that researchers opt for single-anchor attachments under most circumstances, especially during winter when birds may be energetically challenged. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.
Times Cited in Web of Science Core Collection: 0 Total Times Cited: 0 Cited Reference Count: 30
Keywords: survival; HARLEQUIN DUCKS; MOVEMENTS; HABITAT USE; SURF SCOTERS; WHITE-WINGED SCOTERS; BEHAVIOR; Alaska; REMIGIAL MOLT; RADIO TRANSMITTERS; waterbirds; PERFORMANCE; SCOTERS MELANITTA-PERSPICILLATA; subcutaneous anchor; surf scoter; telemetry; transmitter attachment; transmitter retention; white-winged scoter

Species Richness and Distributions of Boreal Waterbird Broods in Relation to Nesting and Brood-Rearing Habitats - Lewis, T. L.; Lindberg, M. S.; Schmutz, J. A.; Bertram, M. R.; Dubour, A. J. (Journal of Wildlife Management, 2015)
Identification of ecological factors that drive animal distributions allows us to understand why distributions vary temporally and spatially, and to develop models to predict future changes to populations-vital tools for effective wildlife management and conservation. For waterbird broods in the boreal forest, distributions are likely driven by factors affecting quality of nesting and brood-rearing habitats, and the influence of these factors may extend beyond singles species, affecting the entire waterbird community. We used occupancy models to assess factors influencing species richness of waterbird broods on 72 boreal lakes, along with brood distributions of 3 species of conservation concern: lesser scaup (Aythya affinis), white-winged scoters (Melanitta fusca), and horned grebe (Podiceps auritus). Factors examined included abundance of invertebrate foods (Amphipoda, Diptera, Gastropoda, Hemiptera, Odonata), physical lake attributes (lake area, emergent vegetation), water chemistry (nitrogen, phosphorus, chlorophyll a concentrations), and nesting habitats (water edge, non-forest cover). Of the 5 invertebrates, only amphipod density was related to richness and occupancy, consistently having a large and positive relationship. Despite this importance to waterbirds, amphipods were the most patchily distributed invertebrate, with 17% of the study lakes containing 70% of collected amphipods. Lake area was the only other covariate that strongly and positively influenced species richness and occupancy of scaup, scoters, and grebes. All 3 water chemistry covariates, which provided alternative measures of lake productivity, were positively related to species richness but had little effect on scaup, scoter, and grebe occupancy. Conversely, emergent vegetation was negatively related to richness, reflecting avoidance of overgrown lakes by broods. Finally, nesting habitats had no influence on richness and occupancy, indicating that, at a broad spatial scale, brood distributions are largely driven by the presence of quality brood-rearing lakes, not nesting habitats. Our findings are relevant to generating conservation plans or management goals; specifically, boreal lakes with abundant amphipods and surface areas >25ha are important habitat for waterbird broods and merit conservation, especially given the patchy distribution of amphipods. Moreover, these high quality brood-rearing lakes are much rarer, and thus more constraining, than are quality nesting habitats, which are likely abundant in the boreal. (c) 2015 The Wildlife Society.
Lewis, Tyler L. Lindberg, Mark S. Schmutz, Joel A. Bertram, Mark R. Dubour, Adam J.
Keywords: Breeding Season; Melanitta fusca; White-winged Scoter; Trophic Interactions; Habitat

Improving population estimates of threatened spectacled eiders: correcting aerial counts for visibility bias - Lewis, T. L.; Swaim, M. A.; Schmutz, J. A.; Fischer, J. B. (ENDANGERED SPECIES RESEARCH, 2019)
Listed as 'threatened' under the US Endangered Species Act in 1993, the spectacled eider Somateria fischeri population in western Alaska, USA, has since rebounded, prompting an assessment of their suitability for delisting. This assessment, however, is limited by aerial-based population estimates that are incompletely corrected for unobserved eiders. Notably, aerial counts of eiders are corrected with a visibility correction factor (VCF), calculated as the ratio of groundbased nest counts to aerial pair counts, which disregards spatial variation in eider density. Accordingly, we (1) stratified our study area into zones of low, medium, and high eider density, (2) developed density-adjusted VCFs for each stratum, (3) evaluated the influence of several ecological factors on VCFs, and (4) estimated eider population size using our density-adjusted VCFs. For the low-density stratum, we estimated a VCF (+/- SE) of 1.35 +/- 0.15, indicating that aerial counts of eider pairs closely matched ground counts of nests. In medium and high-density strata, VCFs increased to 2.46 +/- 0.17 and 3.09 +/- 0.19, respectively, suggesting that aerial detection decreased as eider densities increased. VCFs also increased for surveys that occurred late relative to nest initiation. Population estimates produced with our density-adjusted VCFs were 42% (5580 eiders) lower, on average, than those produced with the traditional VCF, which is currently used. Such large differences underscore the importance of accounting for density when correcting counts for incomplete detection, and, for threatened species such as spectacled eiders, may determine whether populations retain protected status.
Times Cited in Web of Science Core Collection: 4 Total Times Cited: 4 Cited Reference Count: 28
Keywords: Somateria fischeri; Abundance; Detection; Spectacled eider; Stratification; US Endangered Species Act

POLYCYCLIC AROMATIC HYDROCARBONS (PAHS) AND ORGANOCHLORINE PESTICIDES (OCPS) IN TISSUES OF TWO AQUATIC BIRD SPECIES FROM POYANG LAKE, CHINA - Li, Q. Y.; Zhao, Z. H.; Gong, X. H.; Feng, F.; Wu, J. L. (FRESENIUS ENVIRONMENTAL BULLETIN, 2017)
The concentrations and tissue distributions of polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs) in two aquatic bird species (the Mergus squamatus and the Tadorna tadorna) were studied from Poyang Lake, China. The total PAH concentrations in tissues of two species were 119-1609 ng/g dry weight (dw) and 43.7615 ng/g dw, respectively. Low molecular weight PAHs became predominant, especially Phe, Nap and Flu, demonstrating coal combustion was the main pollution source. The total OCP concen-trations were 37.5-182 ng/g dw and 26.9-159 ng/g dw, respectively. Hexachlorocyclohexanes (HCHs), chlordanes and ichlorodiphenyltrichloroethanes (DDTs) were major compounds, and most of them originated from historical use, except DDTs that still have a fresh input. Stable nitrogen and carbon isotopes analysis revealed the Mergus squamatus occupied higher trophic levels and ate fishes as food sources while the Tadorna tadorna preyed mainly on plant -based foods, interpreting the significant difference of PAH concentrations between them. Among tissues, feathers and gonad tissue were targeted by contaminants, and highly positive correlations about PAH concentrations between feathers and blood (R=0.83 for the Mergus squamatus and R=0.97 the Tadorna tadorna), as well as local water area (R=0.92 for the Mergus squamatus and R=0.95 the Tadorna tadorna) were also observed, which is indicated that feathers can be identified as suitable non-destructive bio-monitors for PAHs. Moreover, high contaminant concentrations in gonad tissue can potentially extend genetic risks to next generation, a subject that warrants further research.
Times Cited in Web of Science Core Collection: 2 Total Times Cited: 2 Cited Reference Count: 65
Keywords: PERSISTENT ORGANIC POLLUTANTS; FOOD-WEB; HEAVY-METAL; SURFACE SEDIMENTS; aquatic birds; bio-monitor; ECOLOGICAL RISK; EMISSION FACTORS; FEATHERS; OCPs; PAHs; Poyang Lake; RESIDUES; RIVER; SOURCE APPORTIONMENT; tissue

Homing Success of Adult Buffleheads Bucephala-Albeola to a Maryland USA Wintering Site - Limpert, R. J. (Journal of Wildlife Management, 1980)
Keywords: Nonbreeding Seasons; Dispersal; Bucephala albeola; Bufflehead

Multifocal optical systems and pupil dynamics in birds - Lind, Olle E.; Kelber, Almut; Kroger, Ronald H. H. (Journal of Experimental Biology, 2008)
In animal eyes of the camera type longitudinal chromatic aberration causes defocus that is particularly severe in species with short depth of focus. In a variety of vertebrates, multifocal optical systems compensate for longitudinal chromatic aberration by concentric zones of different refractive powers. Since a constricting circular pupil blocks peripheral zones, eyes with multifocal optical systems often have slit pupils that allow light to pass through all zones, irrespective of the state of pupil constriction. Birds have circular pupils and were therefore assumed to have monofocal optical systems. We examined the eyes of 45 species (12 orders) of bird using videorefractometry, and the results are surprising: 29 species (10 orders) have multifocal systems, and only five species (five orders) have monofocal systems. The results from 11 species (four orders) are inconclusive. We propose that pupils 'switching' between being fully opened (multifocal principle) to maximally closed (pinhole principle) can make multifocal optical systems useful for animals with circular pupils. Previous results indicate that mice have both multifocal optical systems and switching pupils. Our results suggest that parrots may use a similar mechanism. By contrast, owl pupils responded weakly to changes in illumination and stayed remarkably wide even in full daylight. Moreover, the parrots opened their pupils at higher light levels than owls, which correlates with the differences in sensitivity between diurnal and nocturnal eyes.
Keywords: Sea Ducks - General; Physiology

Notes on the feeding technique of the goosander in streams - Lindroth, Arne; Bergstom, E. V. A. (Rept Inst Freshwater Res Drottningholm, 1959)
Four Mergus m. merganser ducklings were observed in a stream tank from 9 weeks of age through development of underwater feeding excursions. When swimming at surface, mergansers move their legs alternately but while diving strokes are simultaneous and vary around the horizontal plane. Jerking of the head permits stationary observations to detect moving objects. Objects moving near the substrate appear to be observed more than those in open water. Holes and niches under rocks were examined by probing with the bill. Small trout and salmon may be almost completely eliminated from an area leaving only those in the most secure niches. ABSTRACT AUTHORS: K. D. Carlander
Keywords: Behavior; Common merganser; Mergus merganser

Long-Distance Molt Migration by British Uk Goosanders Mergus-Merganser - Little, B.; Furness, R. W. (Ringing and Migration, 1985)
Dye-marking and ringing of drake Goosanders after their breeding activities were completed in Britain has proved the existence of a moult migration to the Tana estuary in north Norway. Counts of moulting drakes in Finnmark and estimates of the sizes of breeding and winter populations suggest that almost all drake Goosanders in western Europe moult in this one area.
Keywords: Nonbreeding Seasons; Molt; Migration; Common merganser; Mergus merganser

Complete sequence and gene organization of the mitochondrial genome of scaly-sided merganser (Mergus squamatus) and phylogeny of some Anatidae species - Liu, G.; Zhou, L. Z.; Gu, C. M. (Molecular Biology Reports, 2012)
Times Cited: 1 Liu, Gang Zhou, Li-zhi Gu, Chang-ming 1
Keywords: Taxonomy; Scaly-sided Merganser; Mergus squamatus

Managing coastal area resources by stated choice experiments - Liu, Xin; Wirtz, Kai W. (Estuarine Coastal and Shelf Science, 2010)
In many coastal regions, oil spills can be considered as one of the most important and certainly the most noticeable forms of marine pollution. Efficient contingency management responding to oil spills on waters, which aims at minimizing pollution effects on coastal resources, turns out to be critically important. Such a decision making highly depends on the importance attributed to different coastal economic and ecological resources. Economic uses can, in principal, be addressed by standard measures such as value added. However, there is a missing of market in the real world for natural goods. Coastal resources such as waters and beach cannot be directly measured in money terms, which increases the risk of being neglected in a decision making process. This paper evaluates these natural goods of coastal environment in a hypothetical market by employing stated choice experiments. Oil spill management practice in German North Sea is used as an example. Results from a pilot survey show that during a combat process, beach and eider ducks are of key concerns for households. An environmental friendly combat option has to be a minor cost for households. Moreover, households with less children, higher monthly income and a membership of environmental organization are more likely to state that they are willing to pay for combat option to prevent coastal resources from an oil pollution. Despite that choice experiments require knowledge of designing questionnaire and statistical skills to deal with discrete choices and conducting a survey is time consumed, the results have important implications for oil spill contingency management. Overall, such a stated preference method can offer useful information for decision makers to consider coastal resources into a decision making process and can further contribute to finding a cost-effective oil preventive measure, also has a wide application potential in the field of Integrated Coastal Zone Management (ICZM). (C) 2009 Elsevier Ltd. All rights reserved.
Keywords: Conservation; Sea Ducks - General; Contaminants

Phylogenetic Relationships and Incipient Flightlessness of the Extinct Auckland Islands Merganser - Livezey, B. C. (Wilson Bulletin, 1989)
Phylogenetic relationships and evidence for pectoral reduction in the extinct Aukland Islands Merganser (Mergus australis) were investigated using a plumage-based phylogenetic analysis of the six Recent species of merganser and morphometric comparisons of study skins and skeletal specimens. The hypothesized phylogeny indicates that M. australis diverged from the other Mergus immediately after the Hooded Merganser (Lophodytes cucullatus) and is a member of a basal grade of comparatively small, southern hemisphere mergansers; the Brazilian Merganser (M. octosetaceus) branched next and is the sister-group to the larger, more derived, northern hemisphere species of Mergus. M. australis was unique in its natal and adult plumage characters, including the sexually monochromatic plumage of adults. Morphometric analyses revealed that M. australis was the smallest member of its genus but possessed the longest bills and relatively short wings and tails. Based on regression estimates of body mass and wing area for M. australis, the species had estimated wing-loadings which exceed those for other Mergini and approach the threshold of flightlessness hypothesized by Meunier (1951). Skeletal comparisons confirmed that M. australis had exceptionally long bills, and this also revealed that the species possessed relatively short wing elements and scapulae, as well as sterna characterized by shallow carinae and small caudal widths. These morphological characteristics, hypothesized phylogenetic relationships, and ecological information for M. australis are compared to the typical correlates of insularity in waterfowl listed by Weller (1980), and the evolutionary implications of these characteristics are considered [Other species discussed include M. serrator, M. squamatus, and M. merganser.].
Keywords: Taxonomy; Sea Ducks - General

Phylogeny and evolutionary ecology of modern seaducks (Anatidae: Mergini) - Livezey, Bradley C. (Condor, 1995)
Phylogenetic relationships of modern seaducks (Mergini) were investigated using a cladistic analysis of 137 morphological characters. The analysis produced a single tree (consistency index = 0.692, excluding autapomorphies) with complete resolution of the relationships among the 25 taxa recognized. Phylogenetic inferences include: (1) the eiders (Polysticta and Somateria) constitute a monophyletic group and are the sister-group of other Mergini; (2) the remaining generic groups of Mergini, sequenced in order of increasingly close relationship, are Histrionicus, Melanitta + Camptorhynchus, Clangula, Bucephala + Mergellus, Lophodytes, and Mergus; (3) Somateria is monophyletic with S. fischeri the sister-group of its congeners; (4) the black scoters (Melanitta nigra-group) are the sister-group of other scoters; (5) the Bufflehead (Bucephala albeola) is the sister-group of the goldeneyes (B. clangula and B. islandica); and (6) relationships among mergansers are as presented by Livezey (1989). Bootstrapping revealed that the placement of the Smew as the sister-group of the goldeneyes is only weakly supported, and ancillary analyses revealed that this placement is only one step shorter than its reduction to a trichotomy with the goldeneyes and mergansers (including Lophodytes). A phylogenetic classification of modem seaducks is presented. The Harlequin Duck (H. histrionicus), Long-tailed Duck (Clangula hyemalis), and Steller's Eider (Polysticta stelleri) are highly autapomorphic. Evolutionary patterns of selected ecomorphological characteristics - including body mass, sexual size dimorphism, clutch size, relative clutch mass, nest site, diet, diving method, formation of creches, and biogeography - are examined with respect to the phylogenetic hypothesis.
Keywords: Taxonomy; Sea Ducks - General

A Census of Common Eiders Breeding in Labrador and the Maritime Provinces Canada - Lock, A. R. (Reed, A. (Ed.). Canadian Wildlife Service Report Series, No. 47. Eider Ducks in Canada. V+177p. Canadian Wildlife Service: Ste-Foy, Quebec, Canada. Illus. Maps. Paper, 1987)
Keywords: Breeding Season; Abundance, Distribution, and Trends; Common Eider; Somateria mollissima

A merganser die-off associated with larval Eustrongylides - Locke, L. N.; DeWitt, J. B.; Menzie, C. M.; Kerwin, J. A. (Avian Dis, 1964)
A die-off of red-breasted mergansers on Lake Holly, Virginia Beach, Virginia, was found to be due to a larval Eustrongylides. Massive tissue destruction and hemorrhage was produced by the migration of the larval Eustrongylides. Earlier stages of the same Eustrongylides were found in eastern mosquitofish and silversides upon which the mergansers had been feeding. In addition, residues of DDT were found in mosquitofish, gizzard shad, and 5 mergansers collected from Lake Holly, and in the tissues of 2 mergansers from Back Bay, Virginia. However, the information available was insufficient to establish the significance of these residue levels. || ABSTRACT AUTHORS: Authors
Keywords: Contaminants; Mergus serrator; Red-breasted merganser; Parasites

Distribution, abundance, and habitat association of riparian-obligate and -associated birds in the Oregon Coast Range - Loegering, John P.; Anthony, Robert G. (Northwest Science, 1999)
We studied the abundance, distribution, and habitat associations of the aquatic-foraging riparian-associated vertebrate community along four stream basins transecting managed forests in the Oregon Coast Range, 1992-1994. The riparian-associated community we observed consisted primarily of birds with few observations of mammals. Belted kingfishers (Ceryle alcyon), American dippers (Cinclus mexicanus), great blue herons (Ardea herodias), and mallards (Anas platyrhynchos) comprised >85% of these observations, but we observed only one group (gtoreq1 individual observed together) from this community for each kilometer of stream surveyed. Bird abundances among years were not different (all P > 0.05). Species distribution was affected by stream order, stream basin, and season in each species, but to varying degrees. Belted kingfishers, common mergansers (Mergus merganser), great blue herons, green herons (Butorides striatus), and mallards were more abundant in larger, 6th-orderstreams than in smaller, 4th-order streams (P < 0.05). Dippers used step channel units disproportionally more and riffles disproportionately less than expected (P < 0.5). Similarly, kingfishers used fewer riffles and more pool channel units than was expected (P < 0.5). Key habitat components that were predictive of use were species specific. Most notably, the presence of a forested riparian area, streamside trees, and valley walls that constrain the stream were important predictors of use by the three most abundant species; dippers, kingfishers, and great blue herons. Monitoring programs to assess populations of these species in mountainous habitat must be sensitive to the potential effects of stream order, basin, and season and encompass a large spatial and temporal extent.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Sea Ducks - General; Common merganser; Mergus merganser; Habitat

Stopover Habitats of Spring Migrating Surf Scoters in Southeast Alaska - Lok, Erika K.; Esler, Daniel; Takekawa, John Y.; De La Cruz, Susan W.; Boyd, W. Sean; Nysewander, David R.; Evenson, Joseph R.; Ward, David H. (Journal of Wildlife Management, 2011)
Habitat conditions and nutrient reserve levels during spring migration have been suggested as important factors affecting population declines in waterfowl, emphasizing the need to identify key sites used during spring and understand habitat features and resource availability at stopover sites. We used satellite telemetry to identify stopover sites used by surf scoters migrating through southeast Alaska during spring. We then contrasted habitat features of these sites to those of random sites to determine habitat attributes corresponding to use by migrating scoters. We identified 14 stopover sites based on use by satellite tagged surf scoters from several wintering sites. We identified Lynn Canal as a particularly important stopover site for surf scoters originating throughout the Pacific winter range; approximately half of tagged coastally migrating surf scoters used this site, many for extended periods. Stopover sites were farther from the mainland coast and closer to herring spawn sites than random sites, whereas physical shoreline habitat attributes were generally poor predictors of site use. The geography and resource availability within southeast Alaska provides unique and potentially critical stopover habitat for spring migrating surf scoters. Our work identifies specific sites and habitat resources that deserve conservation and management consideration. Aggregations of birds are vulnerable to human activity impacts such as contaminant spills and resource management decisions. This information is of value to agencies and organizations responsible for emergency response planning, herring fisheries management, and bird and ecosystem conservation. (C) 2011 The Wildlife Society.
Keywords: Nonbreeding Seasons; Melanitta perspicillata; Surf Scoter; Migration; Habitat; SDJV funded

Spatiotemporal associations between Pacific herring spawn and surf scoter spring migration: evaluating a 'silver wave' hypothesis - Lok, E. K.; Esler, D.; Takekawa, J. Y.; De La Cruz, S. W.; Boyd, W. S.; Nysewander, D. R.; Evenson, J. R.; Ward, D. H. (Marine Ecology Progress Series, 2012)
Times Cited: 0 Lok, Erika K. Esler, Daniel Takekawa, John Y. De La Cruz, Susan W. Boyd, W. Sean Nysewander, David R. Evenson, Joseph R. Ward, David H. 0
Keywords: Nonbreeding Seasons; Melanitta perspicillata; Surf Scoter; Migration; Trophic Interactions; Habitat; SDJV funded

Movements of Pre-migratory Surf and White-winged Scoters in Response to Pacific Herring Spawn - Lok, Erika K.; Kirk, Molly; Esler, Daniel; Boyd, W. Sean (Waterbirds, 2008)
We documented the movement and distribution patterns of wintering Surf Scoters (Melanitta perspicillata) and White-winged Scoters (Melanitta fusca) in relation to herring spawn events in the Strait of Georgia, British Columbis. Radio-telemetry and surveys were conducted in Baynes Sound, an important wintering area where scoters feed primarily on clams. In early March, herring spawn events in areas adjacent to Baynes Sound provide a short-term pulse of abundant and easily accessible food, which could affect habitat use by wintering scoters from Baynes Sound. Radio-marked Surf Scoters and White-winged Scoters exhibited limited movements during winter, in contrast to the spring herring spawn season, when both scoter species moved greater distances to access herring eggs. Most individuals were located near spawning locations at least once during the spawning season, and the majority of telemetry locations were close to spawning sites, with Surf Scoters showing a higher association with spawn for both metrics. A marked decrease (66-98%) in the abundance of both scoter species in Baynes Sound was observed coincident with spawn initiation in adjacent sites. We conclude that scoters altered their movement and habitat use patterns in spring to take advantage of herring roe, an energy-rich food source. This dramatic change in behaviour suggests that herring spawn may be of particular importance to these species.
Keywords: Melanitta fusca; Nonbreeding Seasons; White-winged Scoter; Melanitta perspicillata; Surf Scoter; Dispersal; Trophic Interactions; Habitat; SDJV funded

Prevalence and transmission of cercariae causing schistosome dermatitis in Flathead Lake, Montana - Loken, Brent R.; Spencer, Craig N.; Granath, Willard O., Jr. (Journal of Parasitology, 1995)
Numerous studies have been conducted on swimmer's itch, but very few have been in Montana and none on Flathead Lake, the largest, natural freshwater lake in the western United States. We conducted a study to determine the prevalence of hosts transmitting cercariae causing swimmer's itch in this lake. Hosts for this life cycle were determined by direct observation of fresh waterfowl fecal material for the presence of miracidia, and snails for the presence of cercariae. Swimmer's itch-producing cercariae were verified directly by placing various species on the arms of human volunteers and waiting for a reaction. Results of the study were further substantiated using a controlled experiment in which snails were individually infected with miracidia from the suspected waterfowl host and then checked for infection after a 6-wk incubation period. Our findings show that the common merganser (Mergus merganser) and the snail Stagnicola elrodi were natural hosts of the swimmer's itch parasite (Trichobilharzia ocellata) with prevalences of 84% and 2.0%, respectively. To our knowledge this is the first documented case of S. elrodi transmitting the swimmer's itch cercariae.
Keywords: Breeding Season; Common merganser; Mergus merganser; Parasites

An assessment of the effects on seabirds of oil exploration in the Norwegian part of the Skagerrak - Lorentsen, S. H.; Anker-Nilssen, T.; Kroglund, R. T.; Ostnes, J. E. (NINA (Norsk Institutt for Naturforskning) Forskningsrapport, 1993)
This report presents the results of an assessment of the effects on seabirds of possible petroleum exploration in the North Sea east of 7 degree E (Skagerrak). Relative index values for the direct effects of oil spills were calculated by combining oil spill simulations with the distribution of the valued ecosystem components, Common Eider and auks, and their vulnerability indexes, using the analysis system SIMPACT. Based on these results and other considerations, recommendations for limiting possible drilling activity are given.
Keywords: Conservation; Common Eider; Contaminants; Somateria mollissima

Densities of Wintering Scoters in Relation to Benthic Prey Assemblages in a North Atlantic Estuary - Loring, P. H.; Paton, P. W. C.; McWilliams, S. R.; McKinney, R. A.; Oviatt, C. A. (WATERBIRDS, 2013)
During winter, molluscivorous sea ducks often form high density feeding flocks in association with patchily distributed prey, although few studies have documented the substrate and prey characteristics where sea ducks (tribe: Mergini) aggregate and thus what constitutes high-value sea duck foraging habitat. Sea duck surveys were conducted and benthic grab samples collected at sites with different benthic substrate characteristics to compare macroinvertebrate community assemblages in relation to densities of three species of sea ducks: (Surf (Melanitta perspicillata), Black (M. americana), and White-winged (M. fusca) scoters (hereafter "scoters" when combined) during winter (2010-2011) in Narragansett Bay, Rhode Island, an urbanized estuary in the Northwest Atlantic. Overall, the highest densities of scoters (104 +/- 17 per 0.5 km(2)) were found over sand substrates with homogeneous assemblages of infaunal prey. Significantly lower densities of scoters (21 4 per 0.5 km(2)) were associated with mixed sand-gravel-mud substrates that supported epifaunal assemblages and patchily distributed infauna. Mean energy densities (kcal/g) were higher among infaunal (0.64-4.49) vs. epifaunal (0.17-0.53) prey. Overall biomass (g/m(2)) of polychaetes was higher in mixed substrates, and biomass of infaunal bivalves did not significantly differ among habitat type. However, infaunal prey may have been less accessible to scoters at sites with mixed substrates due to a barrier effect created by high-densities of epifauna with low energetic value. Thus, sand-substrate sites supporting infaunal benthic communities may provide high-quality feeding habitat for scoters wintering in the Northwest Atlantic. Understanding the influences of benthic habitat characteristics and macroinvertebrate prey assemblages on distribution of feeding scoters is particularly important for managing sea ducks in areas with increasing anthropogenic development in the coastal zone. Received 16 November 2012, accepted 13 February 2013.
Times Cited in Web of Science Core Collection: 15 Total Times Cited: 15 Cited Reference Count: 47
Keywords: habitat use; COMMON EIDERS; EIDERS SOMATERIA-MOLLISSIMA; SIZE; SEA DUCKS; Mergini; SURF SCOTERS; WHITE-WINGED SCOTERS; DIVING DUCKS; MYTILUS-EDULIS; BLUE MUSSELS; benthic community; HABITAT SELECTION; Melanitta; Narragansett Bay; scoters; winter surveys

Habitat Use and Selection of Black Scoters in Southern New England and Siting of Offshore Wind Energy Facilities - Loring, P. H.; Paton, P. W. C.; Osenkowski, J. E.; Gilliland, S. G.; Savard, J. P. L.; McWilliams, S. R. (JOURNAL OF WILDLIFE MANAGEMENT, 2014)
The southern New England continental shelf is an important region for black scoters (Melanitta americana) during winter and migratory staging periods and a priority area for developing offshore wind energy facilities. However, little is known about the migration phenology and habitat use of black scoters in this portion of their range and this information is necessary to assess potential risks to black scoters during the marine spatial planning process. In this regional black scoter study over 2 winters, we used satellite telemetry and spatial modeling techniques to estimate migratory timing and length of stay, quantify winter home range size and site fidelity between winters, examine key habitat characteristics associated with core-use areas, and map relative probabilities of use across a 3,800-km(2) marine spatial planning area for 2 proposed offshore renewable energy facilities. Black scoters spent nearly 5 months in southern New England, with wide variation among individuals in the size of winter utilization distributions (range 16-12,367 km(2)). Approximately 50% of the tagged birds returned to southern New England during the subsequent winter and had variable fidelity to core-use areas occupied the previous winter. During both winters, black scoter core-use areas were located closer to shore, at shallower water depths, with coarser sediment grain size and higher probability of hard-bottom occurrence relative to available areas. Resource selection functions classified the majority of a nearshore 5-turbine, 34-km(2) renewable energy zone off Block Island as high probability of use by black scoters, whereas an offshore 200-turbine, 667-km(2) federal lease block zone was classified as low to medium-low probability of selection. Wind energy facilities, such as the Block Island site, constructed in relatively shallow (<20m deep), nearshore habitats (<5 km) over hard-bottomed or coarse-sand substrate could displace some foraging black scoters wintering in this region, whereas the larger federal lease block zone located farther offshore is more likely to affect scoters dispersing among core-use areas and during migration between wintering and breeding grounds. (C) 2014 The Wildlife Society.
Times Cited in Web of Science Core Collection: 23 Total Times Cited: 24 Cited Reference Count: 75
Keywords: COMMON EIDERS; EIDERS SOMATERIA-MOLLISSIMA; HARLEQUIN DUCKS; KING EIDERS; MOVEMENTS; Melanitta americana; satellite telemetry; SEA DUCKS; southern New England; resource selection function; SURF SCOTERS; marine spatial planning; WINTER; INFORMATION; black scoter; FARMS; offshore wind energy

Long-tailed Duck (Clangula hyemalis) ecology: insights from the Russian literature. Part 2: European part of the Russian breeding range - Loshchagina, J.; Vardeh, S.; Glazov, P.; Pollet, I. L.; Quillfeldt, P. (POLAR BIOLOGY, 2019)
Long-tailed Ducks (Clangula hyemalis) breed around lakes in tundra vegetation and spend their winter at sea. Their most important wintering site in Europe is the Baltic Sea, and most of the birds wintering there breed in northern Russia. In light of recent population declines, particularly of the Baltic Sea wintering population, it is important to gather all available information for this species to better understand their life history, and to pinpoint the primary threats leading to their decline. Because non-English literature is often neglected, we compiled a review of the information collected in 101 Russian scientific articles published between 1895 and 2017 relevant to Long-tailed Ducks inhabiting the European part of Russia (from Pskov Lake to Yugor Peninsula). We focused on their distribution, breeding densities as well as breeding and feeding biology. The data overall show a similar breeding biology and timing compared to the Asian part of the breeding range. However, due to limitations of the geographical and temporal scope of the reviewed studies, recent trends cannot be detected. Therefore, comprehensive studies are required to understand the contribution of changes in the breeding grounds to population declines observed in the wintering grounds. The data summarized here can provide a basis for such studies, including repeat surveys that will help to understand population trends.
Times Cited in Web of Science Core Collection: 4 Total Times Cited: 5 Cited Reference Count: 114
Keywords: Clangula hyemalis; Long-tailed Duck; Arctic; PATTERNS; Russia