Estimating statistical power to evaluate ongoing waterfowl population monitoring - Lougheed, Lynn W.; Breault, Andre; Lank, David B. (Journal of Wildlife Management, 1999)
The probability of failing to detect a trend when 1 exists has been considered only rarely in the interpretation of monitoring studies. Retrospective power analysis accomplishes this assessment. We apply retrospective power analysis to evaluate both population trends and survey design in the waterfowl surveys conducted by the Canadian Wildlife Service and others around Riske Creek, British Columbia. Eleven of 18 species showed long-term (17 yr) and short-term (10 yr) trends. For the remaining 7 species, the long-term analysis had sufficient power (0.8) to have detected at least a 5% annual change, had 1 existed, which supported the conclusion that little change occurred. However, statistical power and detectable effects varied considerably among species, with a range of 3-14 years of data needed to be able to detect a 5% annual trend. When we used the shorter-term dataset, power was reduced below acceptable levels for 4 of the 7 species failing to show a trend. It would be a mistake toconclude that the numbers of these 4 species were not changing. Statistical power was highest for the species for which the surveys were originally designed, Barrow's goldeneye (Bucephala islandica) and mallards (Anas platyrhynchos), which had narrow confidence intervals and relatively small minimum detectable trends. In contrast, blue-winged teal (Anas discors), gadwall (Anas strepera), green-winged teal (Anas crecca), northern pintail (Anas acuta), and northern shoveler (Anas clypeata) had relatively large minimum detectable trends and wide confidence intervals. Much of the power of these surveys was due to repeated surveying within seasons. For most species, power increased substantially by including up to 4 surveys as replicate observations within a year, but power increased little when data from a fifth or sixth survey were included.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Techniques; Barrow's Goldeneye; Bucephala islandica

Using life-histories to predict and interpret variability in yolk hormones - Love, O. P.; Gilchrist, H. G.; Bety, J.; Wynne-Edwards, K. E.; Berzins, L.; Williams, T. D. (General and Comparative Endocrinology, 2009)
Variation in yolk hormones is assumed to provide the plasticity necessary for mothers to individually optimize reproductive decisions via changes in offspring phenotype, the benefit being to maximise fitness. However, rather than routinely expecting adaptive variation within all species, the pattern and magnitude of yolk hormone deposition should theoretically relate to variation in life-histories. Here we present data on intra-clutch variation in yolk corticosterone in three species along a developmental continuum (European starling (Sturnus vulgaris): fully altricial; black guillemot (Cepphus grylle): semi-precocial; common eider (Somateria mollissima): fully precocial) to examine how and why variation in life-histories might relate to the evolution of variation in yolk steroids. Starlings and guillemots showed a significant increase in yolk corticosterone across the laying sequence; however, we found no pattern within eider clutches. Moreover, starlings showed the largest difference (94.6%) in yolk corticosterone between first- and last-laid eggs, whereas guillemots showed a moderate difference (58.9%). Despite these general species-specific patterns, individuals showed marked variation in the intra-clutch patterns of yolk corticosterone within each species indicating potential differences in intra-clutch flexibility among females. It is well documented that exposure to elevated yolk glucocorticoids reduces offspring quality at birth/hatching in many taxa and it has therefore been proposed that elevated yolk levels may modulate offspring competition and/or facilitate brood reduction under harsh conditions in birds. Our data suggests that intra-clutch variation in yolk corticosterone has the potential to act as an adaptive maternal effect in species where modulation of competition between nest-bound offspring would benefit mothers (starlings and guillemots). However, in precocial species where mothers would not benefit from a modulation of offspring quality, intra-clutch variation in yolk hormones may play little or no adaptive role. While future phylogenetically-controlled studies will be helpful in examining questions of adaptive mechanisms once more data on yolk corticosterone becomes available, our results nonetheless suggest that research on the evolutionary role of yolk hormones can benefit by a prior! incorporating species-specific life-history-driven hypotheses. (C) 2008 Elsevier Inc. All rights reserved.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Physiology

Pre-laying climatic cues can time reproduction to optimally match offspring hatching and ice conditions in an Arctic marine bird - Love, Oliver P.; Gilchrist, H. Grant; Descamps, Sebastien; Semeniuk, Christina A. D.; Bety, Joel (Oecologia (Berlin), 2010)
Individuals breeding in seasonal environments are under strong selection to time reproduction to match offspring demand and the quality of the post-natal environment. Timing requires both the ability to accurately interpret the appropriate environmental cues, and the flexibility to respond to inter-annual variation in these cues. Determining which cues are linked to reproductive timing, what these cues are predicting and understanding the fitness consequences of variation in timing, is therefore of paramount interest to evolutionary and applied ecologists, especially in the face of global climate change. We investigated inter-annual relationships between climatic variation and the timing of reproduction in Canada's largest breeding population of Arctic common eiders (Somateria mollissima) in East Bay, Nunavut. Warmer spring temperatures predicted both earlier mean annual laying dates and the earlier ice-free conditions required by ducklings for post-natal growth. Warmer springs had higher variation in this temperature cue, and the population laying distribution became increasingly positively-skewed in warmer summers, potentially indicating that more low-quality females had the opportunity to commence laying in warmer years. Females that timed laying to match duckling hatching just prior to fully ice-free conditions obtained the highest duckling survival probability. Inter-annual data on repeated breeding attempts revealed that the individuals examined show a similar degree of laying flexibility in response to climatic variation; however, there was significant individual variation in the absolute timing of laying within an average year. This work sheds light on how reproductive timing is related to and influenced by variation in local climate and provides vital information on how climate-related variation in reproductive timing influence a fitness measure in an Arctic species. Results are especially relevant to future work in polar environments given that global climatic changes are predicted to be most intense at high latitudes.
Keywords: Behavior; Breeding Season; Common Eider; Somateria mollissima; Productivity

Variable wind, pack ice, and prey dispersion affect the long-term adequacy of protected areas for an Arctic sea duck - Lovvorn, J. R.; Anderson, E. M.; Rocha, A. R.; Larned, W. W.; Grebmeier, J. M.; Cooper, L. W.; Kolts, J. M.; North, C. A. (Ecological Applications, 2014)
With changing climate, delineation of protected areas for sensitive species must account for long-term variability and geographic shifts of key habitat elements. Projecting the future adequacy of protected areas requires knowing major factors that drive such changes, and how readily the animals adjust to altered resources. In the Arctic, the viability of habitats for marine birds and mammals often depends on sea ice to dissipate storm waves and provide platforms for resting. However, some wind conditions (including weak winds during extreme cold) can consolidate pack ice into cover so dense that air-breathing divers are excluded from the better feeding areas. Spectacled Eiders (Somateria fischeri) winter among leads (openings) in pack ice in areas where densities of their bivalve prey are quite high. During winter 2009, however, prevailing winds created a large region of continuous ice with inadequate leads to allow access to areas of dense preferred prey. Stable isotope and fatty acid biomarkers indicated that, under these conditions, the eiders did not diversify their diet to include abundant non-bivalve taxa but did add a smaller, less preferred, bivalve species. Consistent with a computer model of eider energy balance, the body fat of adult eiders in 2009 was 33-35% lower than on the same date (19 March) in 2001 when ice conditions allowed access to higher bivalve densities. Ice cover data suggest that the eiders were mostly excluded from areas of high bivalve density from January to March in about 30% of 14 winters from 1998 to 2011. Thus, even without change in total extent of ice, shifts in prevailing winds can alter the areal density of ice to reduce access to important habitats. Because changes in wind-driven currents can also rearrange the dispersion of prey, the potential for altered wind patterns should be an important concern in projecting effects of climate change on the adequacy of marine protected areas for diving endotherms in the Arctic.
Lovvorn, James R. Anderson, Eric M. Rocha, Aariel R. Larned, William W. Grebmeier, Jacqueline M. Cooper, Lee W. Kolts, Jason M. North, Christopher A.
Keywords: Somateria fischeri; Spectacled Eider; Trophic Interactions; Habitat; Abundance, Distribution, & Trends; Nonbreeding season

Feeding on epibenthic zooplankton by Long-tailed Ducks: patch structure, profitability, and food web implications - Lovvorn, J. R.; Brooks, M. L. (ECOSPHERE, 2021)
Models of the trophic needs and impacts of mobile predators in food web networks typically do not consider interactions between prey dispersion and threshold prey densities needed for profitable foraging. As a result, the biomass of predators that can be supported, or direct and indirect impacts of those predators on other food web components, may be poorly estimated. In Simpson Lagoon on the U.S. Arctic coast, epibenthic amphipods and especially mysid shrimp comprised most of the diets of fish, and of Long-tailed Ducks (Clangula hyemalis) which strongly dominated prey consumption. Based on mean prey densities and gross estimates of prey biomass consumed, earlier studies estimated that continuous immigration of mysids into the lagoon was needed to support the predators. Comparison of variances from net samples vs. different probability density functions (PDFs) around reported means indicated that prey were not normally distributed, and instead occurred in patches with a skewed and wide range of densities. We used the functional response of captive Long-tailed Ducks eating mysids, and a foraging energetics model, to identify minimum prey densities these diving ducks needed to feed profitably. Based on PDFs that assumed prey densities in all 1-m(2) cells (patches for single feeding dives on potential mysid swarms) were independent, we simulated prey grids with slightly skewed to highly skewed distributions for the reported sample means. Results showed that the greater the range of patch densities, the smaller the fraction of prey biomass that was profitably available to the ducks, thereby increasing the requisite immigration of mysids. Consumption by ectothermic predators further decreased prey available and advanced the date and increased the amount of mysid influx required. The models also showed that the birds had to seek areas with non-independent clusters of high-density feeding patches as prey declined in late summer. Thus, spatially continuous measures of patch structure over larger scales are needed to estimate the fraction of prey that is functionally available. Our study emphasizes that when estimating trophic needs and impacts of mobile endothermic predators, simple means of prey density can be misleading, owing to interactions of prey patch structure with profitability thresholds.
Times Cited in Web of Science Core Collection: 2 Total Times Cited: 2 Cited Reference Count: 104
Keywords: Long-tailed Duck; LESSER SCAUP; DIVING DUCKS; METABOLIC-RATE; amphipods; AYTHYA-FULIGULA; CARRYING-CAPACITY; foraging energetics models; functional response; FUNCTIONAL-RESPONSE; lagoons; MARINE PREDATOR; mysids; MYSIDS CRUSTACEA; patch structure; prey dispersion; THRESHOLD FORAGING BEHAVIOR; TROPHIC STRUCTURE

Niche overlap, threshold food densities, and limits to prey depletion for a diving duck assemblage in an estuarine bay - Lovvorn, J. R.; De La Cruz, S. E. W.; Takekawa, J. Y.; Shaskey, L. E.; Richman, S. E. (Marine Ecology Progress Series, 2013)
Times Cited: 0 Lovvorn, James R. De La Cruz, Susan E. W. Takekawa, John Y. Shaskey, Laura E. Richman, Samantha E. 0
Keywords: Nonbreeding Seasons; Melanitta perspicillata; Surf Scoter; Trophic Interactions

Modeling marine protected areas for threatened eiders in a climatically changing Bering Sea - Lovvorn, James R.; Grebmeier, Jacqueline M.; Cooper, Lee W.; Bump, Joseph K.; Richman, Samantha E. (Ecological Applications, 2009)
Delineating protected areas for sensitive species is a growing challenge as changing climate alters the geographic pattern of habitats as well as human responses to those shifts. When human impacts are expected within projected ranges of threatened species, there is often demand to demarcate the minimum habitat required to ensure the species' persistence. Because diminished or wide-ranging populations may not occupy all viable (and needed) habitat at once, one must identify thresholds of resources that will support the species even in unoccupied areas. Long-term data on the shifting mosaic of critical resources may indicate ranges of future variability. We addressed these issues for the Spectacled Eider (Somateria fischeri), a federally threatened species that winters in pack ice of the Bering Sea. Changing climate has decreased ice cover and severely reduced the eiders' benthic prey and has increased prospects for expansion of bottom trawling that may further affect prey communities. To assess long-term changes in habitats that will support eiders, we linked data on benthic prey, sea ice, and weather from 1970 to 2001 with a spatially explicit simulation model of eider energy balance that integrated field, laboratory, and remote-sensing studies. Areas estimated to have prey densities adequate for eiders in 1970-1974 did not include most areas that were viable 20 years later (1993-1994). Unless the entire area with adequate prey in 1993-1994 had been protected, the much reduced viable area in 1999-2001 might well have been excluded. During long non-foraging periods (as at night), eiders can save much energy by resting on ice vs. floating on water; thus, loss of ice cover in the future might substantially decrease the area in which prey densities are adequate to offset the eiders' energy needs. For wide-ranging benthivores such as eiders, our results emphasize that fixed protected areas based on current conditions can be too small or inflexible to subsume long-term shifts in habitat conditions. Better knowledge of patterns of natural disturbance experienced by prey communities, and appropriate allocation of human disturbance over seasons or years, may yield alternative strategies to large-scale closures that may be politically and economically problematic.
Keywords: Conservation; Somateria fischeri; Spectacled Eider; Nonbreeding Seasons; Habitat

Body Mass Volume and Buoyancy of Some Aquatic Birds and Their Relation to Locomotor Strategies - Lovvorn, J. R.; Jones, D. R. (Canadian Journal of Zoology, 1991)
Body mass, volume, and buoyancy of diving ducks, surface-feeding ducks, auklets, cormorants, and gulls were measured by means of water displacement. Relations of volume and buoyancy to body mass in surface-feeding ducks were linear and did not differ from those of diving ducks if scoters and eiders were excluded. These large-bodies sea ducks (scoters and eiders) had buoyancies 22-28% above values predicted by the common linear regression for surface-feeding ducks and smaller dividing ducks. Thus, scoters and eiders have larger respiratory or plumage air volumes relative to body mass. Although relations of volume and buoyancy to body mass were similar among most ducks, volumes and buoyancies of gulls were much higher, and those of cormorants much lower, than those of ducks. Volumes and buoyancies of auklets were the same as those of ducks of similar mass. The significance to locomotion of the buoyancy of restrained birds depends on predive expiration and ptilosuppression, and reduced buoyancy from compression of air spaces at foraging depths typical for the species.
Keywords: Common Eider; Sea Ducks - General; Melanitta fusca; White-winged Scoter; Somateria mollissima; Physiology

Interactions of body shape, body size and stroke-acceleration patterns in costs of underwater swimming by birds - Lovvorn, J. R.; Liggins, G. A. (Functional Ecology, 2002)
1. For birds, mammals and turtles, costs of swimming by foot propulsion are usually much higher than for propulsion by wings or foreflippers. The propulsive efficiency with which limbs impart thrust to the water is greater for lift-based wings than for drag-based feet, but different acceleration patterns during oscillatory strokes may also alter total drag on the body fuselage (head and trunk). 2. Because wing propulsion allows thrust on both upstroke and downstroke, whereas foot propulsion in many species (perhaps excepting grebes) has little or no thrust on the upstroke, foot propulsion requires higher speeds during a smaller fraction of the stroke to maintain the same mean speed. Because drag increases non-linearly with increasing speed, higher instantaneous speeds in drag-based foot propulsion may cause greater total drag on the body fuselage. 3. Tow-tank measurements have shown that foot-propelled birds that swim with long necks extended have lower fuselage drag at high speeds than do wing-propelled birds that swim with necks retracted. This difference might reduce the higher costs of drag-based foot propulsion, but such effects must be evaluated in the context of drag at a range of speeds throughout oscillatory strokes. 4. In quasi-steady models of horizontal swimming underwater, stroke-acceleration curves for both foot and wing propulsion were applied to a range of bird shapes and sizes. Higher fuselage drag during foot propulsion increased mechanical costs of transport (MCOT, J kg-1 m-1) by 26-40% in various species. Thus, a large fraction of the different costs of wing and foot propulsion might be explained in terms of drag on the body fuselage, independently of the propulsive efficiency of stroking limbs. 5. When drag curves for different body shapes were combined with different oscillatory stroking patterns, swimming with a long neck extended did not reduce the higher total drag associated with drag-based foot propulsion. Thus, although size and shape can affect drag measured at different constant speeds, effects of drag on locomotor costs depend much more on stroke-acceleration patterns of different swimming modes.
Keywords: Physiology; King Eider; Somateria spectabilis

Eiders in offshore pack ice show previously unknown courtship behavior: acceleration of readiness for a constrained breeding period? - Lovvorn, J. R.; Mossotti, R. H.; Wilson, J. J.; McKay, D. (Polar Biology, 2012)
Times Cited: 0 Lovvorn, James R. Mossotti, Regina H. Wilson, Joseph J. McKay, David 0
Keywords: Behavior; Spectacled Eider; Nonbreeding Seasons; somateria fischeri

Wintering eiders acquire exceptional Se and Cd burdens in the Bering Sea: physiological and oceanographic factors - Lovvorn, J. R.; Raisbeck, M. F.; Cooper, L. W.; Cutter, G. A.; Miller, M. W.; Brooks, M. L.; Grebmeier, J. M.; Matz, A. C.; Schaefer, C. M. (Marine Ecology Progress Series, 2013)
Times Cited: 0 Lovvorn, James R. Raisbeck, Merl F. Cooper, Lee W. Cutter, Gregory A. Miller, Micah W. Brooks, Marjorie L. Grebmeier, Jacqueline M. Matz, Angela C. Schaefer, Cortney M. Cooper, Lee/E-5251-2012; Grebmeier, Jacqueline/L-9805-2013 0
Keywords: Somateria fischeri; Spectacled Eider; Nonbreeding Seasons; Contaminants; Physiology; Trophic Interactions

Diet and body condition of spectacled eiders wintering in pack ice of the Bering Sea - Lovvorn, James R.; Richman, Samantha E.; Grebmeier, Jacqueline M.; Cooper, Lee W. (Polar Biology, 2003)
Spectacled eiders (Somateria fischeri) winter among leads in the Bering Sea pack ice, where they dive 40-70 m for benthic prey. During the first icebreaker cruises into that area, esophagi of collected eiders contained only clams, mostly Nuculana radiata, with no trace of the once-dominant Macoma calcarea. Alternative prey used elsewhere (snails, amphipods, other bivalves) were available but not eaten. Eiders ate mainly N. radiata 18-24 mm long, although M. calcarea of this length contained 62% more energy. Percent body lipid of eiders averaged 12+-3% (SD) for 26 adult males and 14+-3% for 12 adult females. Mean body mass (+-SE) of these males in late March (1,688+-21 g) was higher than reported for 53 males after arriving at breeding areas in late May (1,494+-14 g). Body mass of these females (1,550+-35 g) was lower (but not significantly) than reported for 11 females upon arrival at breeding sites (1,623+-46 g). In 1999, the last spectacled eiders left the wintering area on 21 April, 4-8 weeks before their typical arrival at breeding sites. Their location is unknown in the interim, when habitats used appear critical to acquiring reserves for reproduction.
Keywords: Somateria fischeri; Spectacled Eider; Nonbreeding Seasons; Energetics and Nutrition; Trophic Interactions

Limits to benthic feeding by eiders in a vital Arctic migration corridor due to localized prey and changing sea ice - Lovvorn, J. R.; Rocha, A. R.; Jewett, S. C.; Dasher, D.; Oppel, S.; Powell, A. N. (Progress in Oceanography, 2015)
Four species of threatened or declining eider ducks that nest in the Arctic migrate through the northeast Chukchi Sea, where anticipated industrial development may require prioritizing areas for conservation. In this nearshore corridor (10-40 m depth), the eiders' access to benthic prey during the spring is restricted to variable areas of open water within sea ice. For the most abundant species, the king eider (Somateria spectabilis), stable isotopes in blood cells, muscle, and potential prey indicate that these eiders ate mainly bivalves when traversing this corridor. Bivalves there were much smaller than the same taxa in deeper areas of the northern Bering Sea, possibly due to higher mortality rates caused by ice scour in shallow water; future decrease in seasonal duration of fast ice may increase this effect. Computer simulations suggested that if these eiders forage for >15 h/day, they can feed profitably at bivalve densities >200 m(-2) regardless of water depth or availability of ice for resting. Sampling in 2010-2012 showed that large areas of profitable prey densities occurred only in certain locations throughout the migration corridor. Satellite data in April-May over 13 years (2001-2013) indicated that access to major feeding areas through sea ice in different segments of the corridor can vary from 0% to 100% between months and years. In a warming and increasingly variable climate, unpredictability of access may be enhanced by greater effects of shifting winds on unconsolidated ice. Our results indicate the importance of having a range of potential feeding areas throughout the migration corridor to ensure prey availability in all years. Spatial planning of nearshore industrial development in the Arctic, including commercial shipping, pipeline construction, and the risk of released oil, should consider these effects of high environmental variability on the adequacy of habitats targeted for conservation. (C) 2015 Elsevier Ltd. All rights reserved.
Lovvorn, James R. Rocha, Aariel R. Jewett, Stephen C. Dasher, Douglas Oppel, Steffen Powell, Abby N. Si
Keywords: Somateria fischeri; Spectacled Eider; Common Eider; Somateria mollissima; King Eider; Somateria spectabilis; Energetics and Nutrition; Habitat; Nonbreeding season; Polysticta stelleri; Steller’s Eider

Sustaining ecological and subsistence functions in conservation areas: eider habitat and access by Native hunters along landfast ice - Lovvorn, J. R.; Rocha, A. R.; Mahoney, A. H.; Jewett, S. C. (ENVIRONMENTAL CONSERVATION, 2018)
In the Arctic, rapid climate change has kindled efforts to delineate and project the future of important habitats for marine birds and mammals. These animals are vital to subsistence economies and cultures, so including the needs of both animals and hunters in conservation planning is key to sustaining social-ecological systems. In the northeast Chukchi Sea, a nearshore corridor of open water is a major spring migration route for half a million eider ducks that are hunted along the landfast ice. Zoning areas for industrial activities or conservation should consider both eider habitat and hunter access to those habitats from the variable ice edge. Based on benthic sampling in 2010-2012, a model of eider foraging energetics and satellite data on ice patterns in April and May 1997-2011, we mapped the range of positions of the landfast ice edge relative to a given dispersion of habitat suitable for eider feeding. In some sectors, feeding areas were too limited or too far from landfast ice to provide regular hunting access. In other sectors, overlap of the ice edge with eider feeding habitat was quite variable, but often within a consistent geographic range. Areas accessible to hunters were a small fraction of total eider habitat, so areas adequate for conserving eiders would not necessarily include areas that meet the hunters' needs. These results can inform spatial planning of industrial activities that yield cash income critical to subsistence hunting in less developed locations. Our study provides an approach for mapping subsistence conservation areas' throughout the Arctic and an example for such efforts elsewhere.
Times Cited in Web of Science Core Collection: 7 Total Times Cited: 7 Cited Reference Count: 45
Keywords: KING EIDERS; MARINE PROTECTED AREAS; MANAGEMENT; MIGRATION; ARCTIC ALASKA; Arctic sea ice; CANADIAN INUIT; COMMUNITY; conservation planning; ECOSYSTEM; eider habitat; NORTHEASTERN CHUKCHI SEA; PERSISTENT; social-ecological systems; subsistence hunting

Walruses Attack Spectacled Eiders Wintering in Pack Ice of the Bering Sea - Lovvorn, James R.; Wilson, Joseph J.; McKay, David; Bump, Joseph K.; Cooper, Lee W.; Grebmeier, Jacqueline M. (Arctic, 2010)
We observed walruses (Odobenus rosmarus) pursuing spectacled eiders (Somateria fischeri) within pack ice of the Bering Sea, 70-90 km from the nearest land. We used both direct observations from a helicopter and, a heligimbal camera system that can film animals from a helicopter at high altitudes. The eiders were in monospecific flocks of thousands of birds within large leads. The walruses apparently tried to catch the eiders from below; the eiders responded with a "flash expansion" (explosive radial movement), wing-flapping and running along the water surface to escape. Disturbance by individual walruses could restrict flocks of thousands of birds to small portions of the open water. In eight such events that we witnessed over 75 min of observations, we were unable to confirm that walruses captured any of these full-grown, flight-capable eiders. However, the high rate of attacks and the eiders' dramatic escape response suggest that walruses can at times be effective predators on them, and may affect the eiders' dispersion and energy balance.
Keywords: Somateria fischeri; Spectacled Eider; Nonbreeding Seasons; Trophic Interactions

The pathogenesis of a North American H5N2 clade 2.3.4.4 group A highly pathogenic avian influenza virus in surf scoters (Melanitta perspicillata) - Luczo, J. M.; Prosser, D. J.; Pantin-Jackwood, M. J.; Berlin, A. M.; Spackman, E. (BMC VETERINARY RESEARCH, 2020)
Background Aquatic waterfowl, particularly those in the orderAnseriformesandCharadriiformes, are the ecological reservoir of avian influenza viruses (AIVs). Dabbling ducks play a recognized role in the maintenance and transmission of AIVs. Furthermore, the pathogenesis of highly pathogenic AIV (HPAIV) in dabbling ducks is well characterized. In contrast, the role of diving ducks in HPAIV maintenance and transmission remains unclear. In this study, the pathogenesis of a North American A/Goose/1/Guangdong/96-lineage clade 2.3.4.4 group A H5N2 HPAIV, A/Northern pintail/Washington/40964/2014, in diving sea ducks (surf scoters,Melanitta perspicillata) was characterized. Results Intrachoanal inoculation of surf scoters with A/Northern pintail/Washington/40964/2014 (H5N2) HPAIV induced mild transient clinical disease whilst concomitantly shedding high virus titers for up to 10 days post-inoculation (dpi), particularly from the oropharyngeal route. Virus shedding, albeit at low levels, continued to be detected up to 14 dpi. Two aged ducks that succumbed to HPAIV infection had pathological evidence for co-infection with duck enteritis virus, which was confirmed by molecular approaches. Abundant HPAIV antigen was observed in visceral and central nervous system organs and was associated with histopathological lesions. Conclusions Collectively, surf scoters, are susceptible to HPAIV infection and excrete high titers of HPAIV from the respiratory and cloacal tracts whilst being asymptomatic. The susceptibility of diving sea ducks to H5 HPAIV highlights the need for additional research and surveillance to further understand the contribution of diving ducks to HPAIV ecology.
Times Cited in Web of Science Core Collection: 4 Total Times Cited: 4 Cited Reference Count: 67
Keywords: EVOLUTION; Surf scoter; OUTBREAK; WATERFOWL; A(H5N8) VIRUS; CHICKENS; Diving duck; DOMESTIC DUCKS; H5Nx; Highly pathogenic avian influenza virus; PATHOBIOLOGY; Pathogenesis; SOUTH-KOREA; SUBTYPE; WILD BIRDS

Nesting area fidelity and survival of female Common Goldeneyes Bucephala clangula: Are they density-dependent? - Ludwichowski, Ingo; Barker, Richard; Braeger, Stefan (Ibis, 2002)
The breeding histories of 218 female Common Goldeneyes Bucephala clangula were recorded between 1971 and 2000 in a study area in Schleswig-Holstein, northern Germany. Females were first recorded breeding at a median age of 2 years usually in their area of hatching (philopatry). One hundred and two of 140 females (73%) re-nested only in one of the 13 nesting areas (clusters of nestboxes) for all their known life of up to 13 breeding seasons. The remaining 38 individuals moved between different nesting areas at least once between breeding attempts. The two oldest females were still breeding at a minimum age of 15 years (i.e. 13 years between first and last recorded breeding attempt). Temporal variations in annual survival rates of adult females could best be explained by a model with annual survival rate varying independently and randomly about a mean of 0.830 (se=+-0.023) with an estimated sd of +-0.092 (95% CI=0.064, 0.138). No trend in the annual survival rate was detected over the study period of 30 years, although the presence of a moderate trend could not be ruled out. The absence of any discernible trend in survival at a time when the population size increased substantially indicates little, if any, density-dependence in survival of female Goldeneyes during this study.
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Dispersal; Population Dynamics; Survival

25 Years of International Waterbird Count in the Edersee area (winter term 1970/71 to 1994/95) - Luebcke, Wolfgang; Stiebel, Holger (Vogelkundliche Hefte Edertal, 1996)
Within the framework of the International Waterbird Count the Edersee area (Germany) was regularly controlled from 1970/71 to 1994/95. During the last 25 years a positive tendency in the number of some common waterbird species led to an increase of the entire inventory of resting and overwintering waterbirds (p lt 0.001). A distinct increase was reported for the great crested grebe Podiceps cristatus, the tufted duck Aythya fuligula, the common goldeneye Bucephala clangula, the common merganser Mergus merganser, and the cormorant Phalacrocorax carbo. In comparison with Hesse (Germany) the Edersee area is very important with regard to the whooper swan Cygnus cygnus, the common merganser Mergus merganser, the common goldeneye Bucephala clangula, and the little grebe Tachybaptus ruficollis. While in the 1970 decade the artificial lake near Affoldern (Germany) compared to the Edersee attracted nearly 70 per cent of the waterbirds, the ratio has changed to almost 1 to 1 in the last seven years.
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons

Inferring individual rules from collective behavior - Lukeman, Ryan; Li, Yue-Xian; Edelstein-Keshet, Leah (Proceedings of the National Academy of Sciences of the United States of America, 2010)
Social organisms form striking aggregation patterns, displaying cohesion, polarization, and collective intelligence. Determining how they do so in nature is challenging; a plethora of simulation studies displaying life-like swarm behavior lack rigorous comparison with actual data because collecting field data of sufficient quality has been a bottleneck. Here, we bridge this gap by gathering and analyzing a high-quality dataset of flocking surf scoters, forming well-spaced groups of hundreds of individuals on the water surface. By reconstructing each individual's position, velocity, and trajectory, we generate spatial and angular neighbor-distribution plots, revealing distinct concentric structure in positioning, a preference for neighbors directly in front, and strong alignment with neighbors on each side. We fit data to zonal interaction models and characterize which individual interaction forces suffice to explain observed spatial patterns. Results point to strong short-range repulsion, intermediate-range alignment, and longer-range attraction (with circular zones), as well as a weak but significant frontal-sector interaction with one neighbor. A best-fit model with such interactions accounts well for observed group structure, whereas absence or alteration in any one of these rules fails to do so. We find that important features of observed flocking surf scoters can be accounted for by zonal models with specific, well-defined rules of interaction.
Keywords: Behavior; Nonbreeding Seasons; Melanitta perspicillata; Surf Scoter

Ordering dynamics in collectively swimming Surf Scoters - Lukernan, R. (Journal of Theoretical Biology, 2014)
One striking feature of collective motion in animal groups is a high degree of alignment among individuals, generating polarized motion. When order is lost, the dynamic process of reorganization, directly resulting from the individual interaction rules, provides significant information about both the nature of the rules, and how these rules affect the functioning of the collective. By analyzing trajectories of collectively swimming Surf Scoters (Melanitta perspicillata) during transitions between order and disorder, I find that individual speed and polarization are positively correlated in time, such that individuals move more slowly in groups exhibiting lower alignment. A previously validated zone-based model framework is used to specify interactions that permit repolarization while maintaining group cohesion and avoiding collisions. Polarization efficiency is optimized under the constraints of cohesion and collision-avoidance for alignment-dominated propulsion (versus autonomous propulsion), and for repulsion an order of magnitude larger than attraction and alignment. The relative strengths of interactions that optimize polarization also quantitatively recover the speed-polarization dependence observed in the data. Parameters determined here through optimizing polarization efficiency are essentially the same as those determined previously from a different approach: a best-fit model for polarized Surf Scoter movement data. The rules governing these flocks are therefore robust, accounting for behavior across a range of order and structure, and also highly responsive to perturbation. Flexibility and efficient repolarization offers an adaptive explanation for why specific interactions in such animal groups are used. (C) 2014 Elsevier Ltd. All rights reserved.
Lukernan, Ryan
Keywords: Behavior; Melanitta perspicillata; Surf Scoter

Choice of Nest Boxes by Common Goldeneyes Bucephala-Clangula in Ontario Canada - Lumsden, H. G.; Page, R. E.; Gauthier, M. (Wilson Bulletin, 1980)
Choices among boxes offering a variety of features were recorded for goldeneyes in a series of controlled experiments in northern Ontario. Goldeneyes preferred boxes with black interiors, large entrance holes (13 .times. 10 cm) and a depth of at least 33 cm. Compass orientation, alignment with a tree trunk and species of tree on which the boxes were situated were not factors in selection.
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Techniques

Common Goldeneyes Hatching from Cracked Eggs - Lumsden, H. G.; Wenting, R. (Auk, 1976)
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Productivity

Conspecific Brood Parasitism in Common Eiders (Somateria Mollissima): Do Brood Parasites Target Safe Nest Sites? - Lusignan, Alain P.; Mehl, Katherine R.; Jones, Ian L.; Gloutney, Mark L. (Auk, 2010)
Several hypotheses have been proposed to explain the evolution of conspecific brood parasitism (CBP), and recent studies suggest that nest predation may be an important factor in shaping this behavior. We assessed whether individuals that engage in parasitic laying preferentially deposit their eggs in safe nest sites (i.e., risk assessment hypothesis). We tested the predictions of this hypothesis using a population of Common Eiders (Somateria mollissima dresseri) nesting at Table Bay, Labrador, Canada, in 2007. Common Eiders at this location nest in three habitats (dense woody vegetation, open grassy vegetation, and nest shelters) that vary in their exposure to avian predators. We used isoelectric focusing electrophoresis of egg albumen to quantify the frequency and distribution of CBP among habitats. Nest-site safety did not explain patterns of CBP among habitats, given that nests in dense woody vegetation had the highest probability of survival (0.70; 95% confidence interval [CI]: 0.50-0.89) yet had the lowest frequency of CBP (33%). There was also no indication that parasitized and nonparasitized nests differed in their probability of nest survival (0.65 [95% CI: 0.41-0.83] vs. 0.58 [95% CI: 0.33-0.80]). We propose explanations for why our data did not support the risk assessment hypothesis. Received 20 October 2009, accepted 8 April 2010.
Keywords: Behavior; Breeding Season; Common Eider; Somateria mollissima

Polymorphus-Minutus Acanthocephala a Common Parasite in Common Eider Somateria-Mollissima in Norway - Lysfjord, S. (Fauna (Oslo), 1981)
Nine common eider S. mollissima from the Rost archipelago in northern Norway were examined for parasites in summer 1980 in order to evaluate the parasite fauna of Norwegian sea birds. All birds were infested with P. minutus, and in 5 of them > 400 specimens were localized. Weight loss may be caused by the parasite.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Parasites

Body mass, mercury exposure, biochemistry and untargeted metabolomics of incubating common eiders (Somateria mollissima) in three Baltic colonies - Ma, N. L.; Hansen, M.; Therkildsen, O. R.; Christensen, T. K.; Tjornlov, R. S.; Garbus, S. E.; Lyngs, P.; Peng, W. X.; Lam, S. S.; Krogh, A. K. H.; Andersen-Ranberg, E.; Sondergaard, J.; et al. (ENVIRONMENT INTERNATIONAL, 2020)
The Baltic/Wadden Sea Flyway of common eiders has declined over the past three decades. Multiple factors such as contaminant exposure, global warming, hunting, white-tailed eagle predation, decreased agricultural eutrophication and infectious diseases have been suggested to explain the decline. We collected information on body mass, mercury (Hg) concentration, biochemistry and untargeted metabolomics of incubating birds in two colonies in the Danish Straits (Hov Ron, n = 100; Agerso, n = 29) and in one colony in the Baltic proper (Christianso, n = 23) to look into their metabolisms and energy balance. Body mass was available from early and late incubation for Hov Ron and Christianso, showing a significant decline (25-30%) in both colonies with late body mass at Christianso being the lowest. Whole blood concentrations of total mercury Hg were significantly higher in birds at Christianso in the east compared to Hov Ron in the west. All birds in the three colonies had Hg concentrations in the range of <= 1.0 mu g/g ww, which indicates that the risk of effects on reproduction is in the no to low risk category for wild birds. Among the biochemical measures, glucose, fructosamine, amylase, albumin and protein decreased significantly from early to late incubation at Hov Ron and Christianso, reflecting long-term fastening as supported by the decline in body mass. Untargeted metabolomics performed on Christianso eiders revealed presence of 8,433 plasma metabolites. Of these, 3,179 metabolites changed significantly (log(2)-fold change >= 1, p <= 0.05) from the early to late incubation. For example, smaller peptides and vitamin B-2 (riboflavin) were significantly down-regulated while 11-deoxycorticosterone and palmitoylcarnitine were significantly upregulated. These results show that cumulative stress including fasting during incubation affect the eiders' biochemical profile and energy metabolism and that this may be most pronounced for the Christianso colony in the Baltic proper. This amplify the events of temperature increases and food web changes caused by global warming that eventually accelerate the loss in body weight. Future studies should examine the relationship between body condition, temperature and reproductive outcomes and include mapping of food web contaminant, energy and nutrient content to better understand, manage and conserve the populations.
Times Cited in Web of Science Core Collection: 5 Total Times Cited: 5 Cited Reference Count: 63
Keywords: Physiology; Mercury; HEALTH; SEA; CLINICAL-CHEMICAL PARAMETERS; HEMATOLOGY; MORTALITY EVENT; Fitness; Reproduction; BLOOD; Fasting; Untargeted metabolomics

Migratory Connectivity and Nesting Behavior in Harlequin Ducks (Histrionicus histrionicus) Based on Light-level Geolocator Data - MacCallum, B.; Paquet, A.; Bate, L.; Hammond, C.; Smucker, K.; Savoy, L.; Patla, S.; Boyd, W. S. (WATERBIRDS, 2021)
The Harlequin Duck (Histrionicus histrionicus) is a species of conservation priority in western North America. Harlequin Ducks breed in small, isolated populations and have specific nesting requirements. Archival, light-level geolocators are increasingly being used as a low-cost, non-invasive tracking technology to explore migratory connectivity. From 2015-2019, geolocators were deployed on 70 Harlequin Ducks in breeding streams of the Rocky Mountains, Canada and USA, to obtain information on connectivity (breeding to non-breeding), molt-winter sites, dispersal, and breeding phenology. Twenty-two of the 70 geolocators were retrieved from locations in the Rocky Mountains (Alberta, Canada; Montana and Wyoming, USA) and analyzed using the TwGeos and FLightR R packages. Harlequin Ducks from the warmer climate of northwest Montana migrated in spring and started incubation one to two weeks earlier than ducks in west-central Alberta and the greater Yellowstone area. During the non-breeding period, individuals dispersed along the Pacific coast, from Oregon to the Alaskan Panhandle, independent of breeding site. Females that incubated successfully spent 32-34 days incubating, which is several days longer than what is in the literature. Use of geolocators provided detailed information about migration connectivity and breeding behavior in a cost effective and relatively non-invasive manner.
Times Cited in Web of Science Core Collection: 1 Total Times Cited: 1 Cited Reference Count: 44
Keywords: migration; Histrionicus histrionicus; Harlequin Duck; migratory birds; Alberta; FLightR; geolocator; incubation; Montana; REVEAL INCUBATION; Wyoming

An observation of the spring 2006 migration of Black Scoter Melanitta nigra, in Northumberland Strait, interrupted by the Confederation Bridge, New Brunswick - Prince Edward Island - MacKinnon, Colin; Kennedy, Andrew (Canadian Field-Naturalist, 2006)
An observation from the bridge of a flock of Black Scoters suggests that, nine years after construction, the 12.9 km Confederation Bridge may still be a partial barrier to bird migration. Only 3 of 18 scoters (16.7%) crossed over the structure during the observation period.
Keywords: Nonbreeding Seasons; Migration; Black Scoter; Melanitta nigra

Migrant Common Eider, Somateria mollissima, Collisions with Power Transmission Lines and Shortwave Communication Towers on the Tantramar Marsh in Southeastern New Brunswick - MacKinnon, C. M.; Kennedy, A. C. (Canadian Field-Naturalist, 2011)
Times Cited: 0 MacKinnon, Colin M. Kennedy, Andrew C. 0
Keywords: Conservation; Nonbreeding Seasons; Migration; Common eider; somateria mollissima

Waterbird predation on fish in western Lake Erie: A bioenergetics model application - Madenjian, Charles P.; Gabrey, Steven W. (Condor, 1995)
To better understand the role of piscivorous waterbirds in the food web of western Lake Erie, we applied a bioenergetics model to determine their total fish consumption. The important nesting species included the Herring Gull (Larus argentatus), Ring-billed Gull (L. delawarensis), Double-crested Cormorant (Phalacrocorax auritus), Great Blue Heron (Ardea herodias), Black-crowned Night-Heron (Nycticorax nycticorax), and Great Egret (Casmerodius albus). The impact of migrant waterbirds, including the Red-breasted Merganser (Mergus serrator), on western Lake Erie fish biomass was also considered in the analysis. According to the modeling results, during the early 1990s, piscivorous waterbirds consumed 13,368 tonnes of fish from western Lake Erie each year. This tonnage was equivalent to 15.2% of the prey fish biomass needed to support the walleye (Stizostedion vitreum) population in western Lake Erie during a single growing season. The model application was useful in quantifying energy flow between birds and fish in a large lake ecosystem.
Keywords: Nonbreeding Seasons; Trophic Interactions; Mergus serrator; Red-breasted merganser

Assessing regional populations of ground-nesting marine birds in the Canadian High Arctic - Maftei, M.; Davis, S. E.; Mallory, M. L. (Polar Research, 2015)
The Queens Channel region of Nunavut is an ecologically distinct area within the Canadian High Arctic consisting of an extensive archipelago of small, low-lying gravel islands throughout which form several localized but highly productive polynyas. We used aerial survey and colony-monitoring data to assess regional-and colony-level fluctuations in the number of birds in this region between 2002 and 2013. Regional and colony-specific monitoring suggested that common eider (Somateria mollissima) numbers are increasing, while numbers of Arctic terns (Sterna paradisaea) may be in decline. Based on these data, we suggest that even infrequent comprehensive surveys are more useful than annual monitoring at specific sites in generating an accurate assessment of ground-nesting seabird populations at the regional level, and that dramatic fluctuations at individual colonies probably belie the overall stability of regional populations.
Maftei, Mark Davis, Shanti E. Mallory, Mark L.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Abundance, Distribution, & Trends

Birds of the Thingvallavatn Area - Magnusson, K. G. (Oikos, 1992)
This paper is a general description of the birdlife of Thingvallavatn [Iceland] and the surrounding area. Most of the data were collected during regular surveys of the lake in 1988 and 1989, but considerable use was made of earlier data collected by the author and of information from local farmers. The main emphasis is on the waterbirds, but landbirds occurring regularly in the area are also discussed. The distribution and estimated numbers of the various species of waterbirds are given as well as their seasonal variation in numbers. The numbers of breeding waterbirds are rather small, but numbers increase considerably in autumn due to an influx of migrating birds, with total numbers reaching a few hundred in autumn and early winter. In particular, 50 or more great northern divers stay on the lake in October-December as well as 200-400 red-breasted mergansers. The changes in the avifauna of the area are discussed and possible causes mentioned.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons; Red-breasted merganser

Evidence of strong population bottleneck in genetics of endangered Brazilian Merganser (Mergus octosetaceus) - Maia, T. A.; Campos, D. P.; Silva, L. R.; Lins, L. V.; Ribeiro, F.; Sebaio, F.; Rodrigues, F. R.; Dantas, G. P. M. (JOURNAL OF ORNITHOLOGY, 2020)
The Brazilian Merganser is one of the rarest birds of South America with three known remnant populations in Brazil and only 250 individuals existing in the wild. Thus, evaluating the genetic variability within the remaining population is essential to its conservation. This study assessed genetic diversity of remnant populations by mtDNA (Dloop and cytb) and nDNA (MUSK 13 intron, five microsatellites) markers, giving support to management and conservation efforts. Seventy-one samples were collected during eight years from Chapada dos Veadeiros National Park (PNCV), Serra da Canastra National Park (PNSC), and Alto do Paranaiba region (APR). Cytochrome b, Dloop, and MUSK intron showed only one haplotype, indicating a loss of genetic variability for the Brazilian Merganser. The microsatellites confirmed low genetic variability (1-4 alleles). Despite the low variability observed, it was possible to infer minor differentiation between remnant populations, with PNCV locale being the most differentiated subgroup, due to its being isolated by greater distance from the others. Low genetic diversity observed in Brazilian Merganser, is expected to be found in Critically Endangered species, due to small population size, being result of high inbreeding rates, and gene drift effects. Thus, our genetic data have confirmed the extremely critical status of the Brazilian Merganser, making it necessary to create an immediate recovery program for their populations, and develop a management plan to integrate and preserve all remnant populations to avoid the species extinction.
Times Cited in Web of Science Core Collection: 0 Total Times Cited: 0 Cited Reference Count: 42
Keywords: CONSERVATION; REGION; MITOCHONDRIAL-DNA; DIVERSITY; CANASTRA-NATIONAL-PARK; Endangered species; Genetic conservation; Microsatellite; mtDNA; nDNA; NUCLEAR; SOFTWARE

DNA sampling from eggshells and microsatellite genotyping in rare tropical birds: Case study on Brazilian Merganser - Maia, T. A.; Vilaca, S. T.; da Silva, L. R.; Santos, F. R.; Dantas, G. P. D. (GENETICS AND MOLECULAR BIOLOGY, 2017)
This study shows that sampling maternal DNA from hatched and abandoned eggshells is a viable noninvasive strategy for studying the genetics of rare or endangered tropical birds, as exemplified here by the Brazilian Merganser (Mergus octosetaceus). Eighteen microsatellites were isolated from enriched libraries and nine heterologous loci from related species were tested. Seven loci were amplified successfully, with five of them being polymorphic. These loci exhibited amplicons ranging from 110 to 254 bp for 132 samples, with 60 from eggshells and 72 from blood or muscle samples. The number of alleles for M. octosetaceus ranged from one to six (mean = 3.71), which is low compared to M. merganser (1-15 alleles), a 'least concern' species. Genetic diversity did not differ significantly between noninvasive and invasive samples (Z(u) = 0.31, p = 0.37). Thus, noninvasive sampling, as demonstrated here with eggshells, provides an efficient means to assess genetic diversity in tropical birds without the need to capture and handle them.
Times Cited in Web of Science Core Collection: 5 Total Times Cited: 5 Cited Reference Count: 33
Keywords: genetic diversity; POPULATION; DNA; SOFTWARE; endangered birds; LOCI; MARKERS; Mergus; NONINVASIVE GENETIC-ANALYSIS; noninvasive samples; PCR

Importance of large diameter trees and snags for cavity nesting ducks and raptors in the northern forests of Quebec - Maisonneuve, Charles (Vogelwarte, 2003)
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Common merganser; Mergus merganser; Habitat; Hooded Merganser; Lophodytes cucullatus

Comparability and repeatability of candling and floating methods for estimating embryo age of waterbird eggs - Maliguine, A. M.; Latty, C. J.; Watford, E. M.; Hollmen, T. E. (WATERBIRDS, 2022)
Determining embryo age is important for predicting hatch dates, planning nest visitation schedules, and as a model covariate examining factors affecting nest survival and behavior. Two common methods of estimating embryo age are egg candling and egg flotation (floating). Despite the reliance on these methods, there is little information regarding the repeatability of these techniques between multiple observers, or whether these techniques produce equivalent estimates. To determine how these methods compare and if precision of each method is biased by individual observers, paired observers candled and floated the same Common Eider (Somateria mollissima) eggs. We compared differences in embryo-age estimates across incubation between (1) candling and floating, (2) paired observers candling eggs, and (3) paired observers floating eggs. Floating and candling produced different embryo-age estimates during some periods of incubation. Although most estimates deviated by a few days, inconsistencies could impact results and statistical power when methods are interchanged between projects or across years. Observers derived different embryo-age estimates for candling, but not for floating, suggesting flotation may be more reliable. Our results suggest caution when combining candling and floating-derived data when collected across incubation stages. Investigators should consider how data collected by multiple observers may affect their research question. Received 22 Apr 2021, accepted 21 Sept 2022.
Times Cited in Web of Science Core Collection: 0 Total Times Cited: 0 Cited Reference Count: 20
Keywords: CLUTCH SIZE; COMMON EIDERS; incubation; ACCURACY; egg candling; egg flotation; embryo age; FLOTATION; INCUBATION DAY

Hepatic trace element concentrations of breeding female common eiders across a latitudinal gradient in the eastern Canadian Arctic - Mallory, C. D.; Gilchrist, H. G.; Robertson, G. J.; Provencher, J. F.; Braune, B. M.; Forbes, M. R.; Mallory, M. L. (MARINE POLLUTION BULLETIN, 2017)
We examined hepatic concentrations of arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), manganese (Mn), mercury (Hg), rubidium (Rb), selenium (Se) and zinc (Zn) in 10 breeding female common eiders (Somateria mollissima) from each of three colonies across 20 degrees of latitude. Levels of many elements were elevated in eiders, although generally below levels of toxicological concern. We found significant differences in concentrations of As, Rb, Hg, Mn and Se among colonies, but not in a consistent pattern with latitude, and Hg:Se molar ratios did not vary among colonies. Furthermore, overlap in element concentrations from birds at different colonies meant that we could not reliably differentiate birds from different colonies based on a suite of their hepatic trace element concentrations. We encourage other researchers to assess baseline trace element levels on this important, harvested species, as a means of tracking contamination of nearshore benthic environments in the circumpolar Arctic.
Times Cited in Web of Science Core Collection: 12 Total Times Cited: 12 Cited Reference Count: 72
Keywords: Somateria mollissima; SOMATERIA-MOLLISSIMA; KING EIDERS; TEMPORAL TRENDS; Liver; SEABIRDS; CONTAMINANTS; SELENIUM; FRESH-WATER; CADMIUM; Contaminant; Eider duck; HEAVY-METALS; Marine bird; MERCURY LEVELS

Common merganser: Mergus merganser - Mallory, Mark; Metz, Karen (Birds of North America, 1999)
Keywords: Breeding Season; Nonbreeding Seasons; Common merganser; Mergus merganser

Site fidelity, breeding habitats, and the reproductive strategies of sea ducks - Mallory, M. L. (Studies in Avian Biology, 2015)
Reproductive strategies describe how species allocate resources to produce offspring and include time and energy invested in nest site choice, egg production, incubation, nest defense, and chick rearing. Sea ducks exhibit considerable variation in all of these parameters but typically have high annual survival, high natal and breeding site fidelity, and variable annual reproductive success compared to other groups of waterfowl. Collectively, these traits make sea ducks susceptible to anthropogenic threats including habitat change, and many populations are in decline.
Keywords: Behavior; Breeding season; Survival; Habitat

Movements of Long-tailed Ducks wintering on Lake Ontario to breeding areas in Nunavut, Canada - Mallory, Mark L.; Akearok, Jason; North, Norm R.; Weseloh, D. Vaughan; Lair, Stephane (Wilson Journal of Ornithology, 2006)
We used implanted satellite transmitters to track the northbound (spring) and southbound (fall) migration and possible breeding locations of three Long-tailed Ducks (Clangula hyemalis) wintering on western Lake Ontario in Ontario, Canada. The birds exhibited short, rapid migration movements punctuated by extended periods of up to 30 days at staging areas. For much of the nesting period (similar to 10 June to 10 July), the birds remained inland of western Hudson Bay in Nunavut. During fall migration, they circumnavigated Hudson Bay to its eastern coast, opposite the coast they had followed in spring, for a mean travel distance of 6,760 km. Identification of these previously unknown, key migration sites fills some important information gaps on Long-tailed Ducks in eastern Canada, and it augments what is known about important coastal marine habitats in the Arctic.
Keywords: Breeding Season; Nonbreeding Seasons; Clangula hyemalis; Long-tailed Duck; Migration; Population Delineation

Increasing cadmium and zinc levels in wild common eiders breeding along Canada's remote northern coastline - Mallory, M. L.; Braune, B. M.; Robertson, G. J.; Gilchrist, H. G.; Mallory, C. D.; Forbes, M. R.; Wells, R. (Science of the Total Environment, 2014)
The common eider (Somateria mollissima) is an abundant sea duck breeding around the circumpolar Arctic, and is an important component of subsistence and sport harvest in some regions. We determined hepatic cadmium (Cd) and zinc (Zn) concentrations in the livers of breeding females sampled during three time periods including 1992/3, 2001/2 and 2008 at three sites spanning 53.7 degrees N-75.8 degrees N in the eastern Canadian Arctic. At all sites, concentrations of both Cd and Zn increased similar to 300% over this time period. The reasons for this rapid increase in concentrations are unclear. (c) 2013 Elsevier B.V. All rights reserved.
Mallory, Mark L. Braune, Birgit M. Robertson, Gregory J. Gilchrist, H. Grant Mallory, Conor D. Forbes, Mark R. Wells, Regina
Keywords: Breeding Season; Common Eider; Contaminants; Somateria mollissima

Contaminants in common elders (Somateria mollissima) of the Canadian Arctic - Mallory, Mark L.; Braune, Birgit M.; Wayland, Mark; Gilchrist, H. Grant; Dickson, D. Lynne (Environmental Reviews, 2004)
Keywords: Common Eider; Contaminants; Somateria mollissima

First Report of Scoters (Melanitta spp.) along Eastern Baffin Island, Nunavut, Canada - Mallory, M. L.; Chardine, J.; Gilliland, S. (ARCTIC, 2020)
In September of 2017 and 2018, we observed hundreds of scoters (Melanitta spp.) in fiords in Arctic Canada, approximately 1100 - 1800 km north of their previous northernmost observations. Given the remote locations and timing of observations, we do not know if these represent previously undiscovered areas where birds moult or new movements to Arctic locations. Moreover, the provenance of these sea ducks is unclear, as no evidence of movements to this region was indicated by large-scale satellite tracking of North American scoters during the last decade.
Times Cited in Web of Science Core Collection: 0 Total Times Cited: 0 Cited Reference Count: 29
Keywords: scoter; BIRDS; Arctic; COSTS; Melanitta; range

Status of the Harlequin Duck Histrionicus histrionicus on Baffin Island, Nunavut, Canada - Mallory, M. L.; Fontaine, A. J.; Akearok, J. (Wildfowl, 2003)
The eastern North American Harlequin Duck Histrionicus histrionicus is a small, uncommon seaduck that was last recorded on Baffin Island, Nunavut, Canada, in 1931. Between 1999 and 2001, Inuit hunters and elders were interviewed and river and coastal surveys were conducted to determine whether this duck still occurred on Baffin Island. Inuit community knowledge indicated that this species still inhabited the southeastern part of the island (Meta Incognita Peninsula), but that it may occasionally be found further north than previously reported. Several hunters from Kimmirut also reported observing females with broods. Only three individuals were found near Igaluit during surveys, suggesting that the species is uncommon and dispersed. None the less, this represents the first evidence in 70 years that this species is still extant on the island.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Harlequin duck; Histrionicus histrionicus

Harlequin Ducks in Nunavut - Mallory, Mark L.; Fontaine, Alain J.; Akearok, Jason A.; Gilchrist, H. Grant (Waterbirds, 2008)
The distribution and abundance of the Harlequin Duck (Histrionicus histrionicus) is poorly known in Arctic Canada. The limited historical information on this species is summarized, and new field surveys and interviews with Inuit hunters in 1998-2002 were also conducted. Recent data confirmed that Harlequins still occur on Baffin Island and are breeding. The majority of new data on this duck come from the Kimmirut area of southeastern Baffin Island, where surveys in the 1930s also found the species. However, it occurs as far west as Cape Dorset, and as far north as Clyde River. Few birds were observed during recent field surveys, Suggesting that the population on Baffin Island is small and dispersed. Future monitoring of Harlequin Ducks in Nunavut will probably be best accomplished rising community-based surveys by hunters.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Harlequin duck; Histrionicus histrionicus

Identifying key marine habitat sites for seabirds and sea ducks in the Canadian Arctic - Mallory, M. L.; Gaston, A. J.; Provencher, J. F.; Wong, S. N. P.; Anderson, C.; Elliott, K. H.; Gilchrist, H. G.; Janssen, M.; Lazarus, T.; Patterson, A.; Pirie-Dominix, L.; Spencer, N. C. (ENVIRONMENTAL REVIEWS, 2019)
The Canadian Arctic hosts millions of marine birds annually, many of which aggregate in large numbers at well-defined sites at predictable times of the year. Marine habitats in this region will be under increasing threats from anthropogenic activities, largely facilitated by climate change and long-term trends of reduced sea ice extent and thickness. In this review, we update previous efforts to delineate the most important habitats for marine birds in Arctic Canada, using the most current population estimates for Canada, as well as recent information from shipboard surveys and telemetry studies. We identify 349 160 km(2) of key habitat, more than doubling earlier suggestions for key habitat extent. As of 2018, 1% of these habitats fall within the boundaries of legislated protected areas. New marine conservation areas currently being finalized in the Canadian Arctic will only increase the proportion protected to 13%.
Times Cited in Web of Science Core Collection: 17 Total Times Cited: 19 Cited Reference Count: 351
Keywords: COMMON EIDERS; SOMATERIA-MOLLISSIMA-BOREALIS; seabird; marine spatial planning; BARROW STRAIT AREA; Canadian Arctic; EASTERN LANCASTER SOUND; foraging radius; GULL PAGOPHILA-EBURNEA; LONG-LIVED BIRD; marine; NORTH WATER POLYNYA; PRINCE LEOPOLD ISLAND; RAZORBILLS ALCA-TORDA; THICK-BILLED MURRES

Marine birds breeding in Penny Strait and Queens Channel, Nunavut, Canada - Mallory, Mark L.; Gilchrist, H. Grant (Polar Research, 2003)
Surveys of breeding birds on small islands in Penny Strait and Queens Channel, Nunavut Territory, Canada, were conducted in July 2002 and 2003. Approximately 3600 marine birds were observed, with the most common species being Arctic terns (Sterna paradisaea, N=2400) and common eiders (Somateria mollissima borealis, N=620). We observed no Ross's gulls (Rhodostethia rosea) in either year, and we found ivory gulls (Pagophila eburnea) only in 2003, even though these species commonly bred here in the 1970s. This previously unsurveyed region supports numerous breeding marine birds, but reproductive success on these small islands may be dependent on annual ice conditions and consequent movements of Arctic foxes (Alopex lagopus).
Keywords: Breeding Season; Abundance, Distribution, and Trends; Common Eider; Sea Ducks - General

Marine birds of the Hell Gate Polynya, Nunavut, Canada - Mallory, Mark L.; Gilchrist, H. Grant (Polar Research, 2005)
The importance of the Hell Gate Polynya to marine birds in High Arctic Canada has not been assessed for two decades. Our breeding season surveys in 2002-04 found 19 species of marine birds using the polynya, in annual numbers perhaps reaching 25 000 individuals. The site appears to support nationally significant populations of northern fulmar (Fulmarus glacialis), Thayer's gull (Larus thayeri) and High Arctic brant (Branta bernicla hrota), as well as locally important numbers of other species including common eiders (Somateria mollissima borealis) and black guillemots (Cepphus grylle). The polynya may be particularly important for migration, as many species are observed here earlier than elsewhere in the High Arctic.
Keywords: Abundance, Distribution, and Trends; Common Eider; Sea Ducks - General

Unusual migration mortality of King Eiders in central Baffin Island - Mallory, Mark L.; Gilchrist, H. Grant; Jamieson, Sarah E.; Robertson, Gregory J.; Campbell, Douglas G. (Waterbirds, 2001)
In October 1999, approximately 110 King Eiders (Somateria spectabilis) were found on the ground in the middle of Baffin Island, indicating that these birds had been following an overland migration. The composition of the flock was mixed in both sex (44% female, 56% male) and age of birds (62% hatch year, 38% after hatch year). Approximately 40 birds flew off after resting for six days on the frozen ground. Of the remaining birds that died, predators ate about 15, and 55 were recovered by staff from a local radar site. All eider carcasses carried fat reserves, although there were differences in body mass related to age and sex. Most birds had injuries consistent with crashing into an object at high speed, but in the absence of any obvious vertical obstacles in this region, it appears that this flock flew into the ground during conditions of poor visibility, perhaps facilitated by the formation of cataracts in their eyes.
Keywords: Nonbreeding Seasons; Migration; King Eider; Somateria spectabilis; Survival

Leucocyte profiles of Arctic marine birds: correlates of migration and breeding phenology - Mallory, M. L.; Little, C. M.; Boyd, E. S.; Ballard, J.; Elliott, K. H.; Gilchrist, H. G.; Hipfner, J. M.; Petersen, A.; Shutler, D. (Conservation Physiology, 2015)
Most Arctic marine birds are migratory, wintering south of the limit of annual pack ice and returning north each year for the physiologically stressful breeding season. The Arctic environment is changing rapidly due to global warming and anthropogenic activities, which may influence the timing of breeding in relation to arrival times following migration, as well as providing additional stressors (e.g. disturbance from ships) to which birds may respond. During stressful parts of their annual cycle, such as breeding, birds may reallocate resources so that they have increased heterophil-to-lymphocyte ratios in their white blood cell (leucocyte) profiles. We analysed leucocyte profiles of nine species of marine birds to establish reference ranges for these species in advance of future Arctic change. Leucocyte profiles tended to cluster among taxonomic groups across studies, suggesting that reference values for a particular group can be established, and within species there was evidence that birds from colonies that had to migrate farther had higher heterophil-to-lymphocyte ratios during incubation than those that did not have to travel as far, particularly for species with high wing loading.
Mallory, Mark L. Little, Catherine M. Boyd, Ellen S. Ballard, Jennifer Elliott, Kyle H. Gilchrist, H. Grant Hipfner, J. Mark Petersen, Aevar Shutler, Dave
Keywords: Common Eider; Somateria mollissima; Physiology

Notes on egg laying and incubation in the Common Merganser - Mallory, Mark L.; Lumsden, Harry G. (Wilson Bulletin, 1994)
Keywords: Breeding Season; Common merganser; Mergus merganser

Nesting habits of Hooded Mergansers Mergus cucullatus in northeastern Ontario - Mallory, M. L.; Lumsden, H. G.; Walton, R. A. (Wildfowl, 1993)
We studied the nesting habits of Hooded Mergansers in northeastern Ontario. Twelve females exhibited vigorous nest defence from early incubation onwards; seven incubating females spent 85.3% of their day on the nest, taking an average of 4.7 recesses each day, each with an average duration of 60 minutes. They lost up to 16% body mass during incubation. Our results confirm earlier studies which suggested that interspecific nest parasitism is a common feature of Hooded Mergansers nesting biology.
Keywords: Behavior; Breeding Season; Hooded Merganser; Lophodytes cucullatus

Colonial Marine Birds Influence Island Soil Chemistry Through Biotransport of Trace Elements - Mallory, M. L.; Mahon, L.; Tomlik, M. D.; White, C.; Milton, G. R.; Spooner, I. (Water Air and Soil Pollution, 2015)
Marine birds are important vectors of nutrient and contaminant transfer from sea to land. In eastern Nova Scotia, Canada, colonial marine birds nest on specific nearshore islands within archipelagoes, and we predicted that soils on islands with bird colonies would have higher concentrations of selected trace elements (notably K, Ca, As, Cd, Cu, Pb, Se, Hg, and Zn) than soils on islands without colonies. In this study, common eider (Somateria mollissima), Leach's storm petrel (Oceanodroma leucorhoa), black guillemot (Cepphus grylle), double-crested cormorant (Phalacrocorax auritus), great black-backed gull (Larus marinus), and herring gull (Larus argentatus) were considered to be the principal avian vectors for contaminant transfer. Results indicate that soils from islands with bird colonies had unique chemical compositions and commonly displayed elevated concentrations of K, Ca, Cu, Se, and Zn when compared to islands without colonies. Thus, marine birds feeding in the nearby marine zone move pollutants and nutrients from the ocean to nesting islands, potentially influencing habitat quality for coastal terrestrial species.
Mallory, Mark L. Mahon, Lewis Tomlik, Molly D. White, Chris Milton, G. Randy Spooner, Ian
Keywords: Breeding Season; Common Eider; Contaminants; Somateria mollissima

Movements on the nest during incubation by cavity-nesting waterfowl - Mallory, Mark L.; McNicol, Donald K. (Wildfowl, 1997)
We studied rates of movement on nests by wild, incubating Common Goldeneyes and Hooded Mergansers nesting in north-east Ontario in relation to ambient temperature and stage of incubation. Goldeneyes moved least frequently on the nest at all times. For both species, time intervals between movements were longer for overnight incubation sessions, and intervals remained relatively constant through incubation for morning, afternoon and overnight sessions (except for overnight sessions of Goldeneyes which increased). Our results suggest that ambient temperature influences on-nest activities of cavity-nesting ducks differently than ground-nesting species, and that there is a general relationship between body size and movements on the nest for waterfowl.
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye; Hooded Merganser; Lophodytes cucullatus

Risk-taking by incubating Common Goldeneyes and Hooded Mergansers - Mallory, Mark L.; McNicol, Donald K.; Walton, Russell A.; Wayland, Mark (Condor, 1998)
We studied nest defense by Common Goldeneyes (Bucephala clangula) and Hooded Mergansers (Lophodytes cucullatus) nesting near Sudbury, Canada between 1989-1995. As incubation proceeded, female Common Goldeneyes took greater risks by allowing the observer to approach the nest more closely before flushing, landing closer to the nest after flushing, vocalizing more commonly when flushed, and giving more broken wing or distraction displays. Hooded Merganser females exhibited relatively strong defense at all stages, including giving distraction displays much earlier in incubation. An index of all four behaviors increased for each species as incubation proceeded. Nest defense by these cavity-nesting ducks differed from patterns known for ground-nesting waterfowl, perhaps due to effects of nest location, predation type and intensity, and nest parasitism. Future nest defense studies should consider the overall suite of behaviors that comprise parental strategies for defending their nests and/or offspring.
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye; Hooded Merganser; Lophodytes cucullatus

Habitat quality and reproductive effort of common goldeneyes nesting near Sudbury, Canada - Mallory, Mark L.; McNicol, Donald K.; Weatherhead, Patrick J. (Journal of Wildlife Management, 1994)
To determine whether common goldeneyes (Bucephala clangula) responded to habitat alteration caused by acid rain, we examined how female goldeneyes allocated reproductive effort in relation to the quality of their nesting lake in an acid-stressed region near Sudbury, Ontario, during 1988-90. Goldeneyes are primarily insectivorous, and we predicted that higher quality females (i.e., heavier or with previous breeding experience) or females nesting on lakes with abundant aquatic invertebrates (i.e., without fish and often acidic in our study area) would allocate more resources to their clutch. Early nesting females laid clutches of greater mass than did late nesting females (P = 0.008), and females nesting on higher quality lakes lacking fish laid heavier clutches than did females nesting on lower quality lakes containing fish (P 0.03, after controlling for effects of clutch initiation date). Variation in clutch mass was achieved primarily by varying the number of eggs laid, although females with breeding experience tended to lay larger eggs (P = 0.07). Female goldeneyes nesting in apparent high quality habitats invest more in their clutches than do females nesting in low quality habitats, supporting the prediction that goldeneyes may derive short-term benefits when breeding in fishless habitats because of reduced competition with fish for common prey. However, the long-term consequences for goldeneye populations breeding in acid-stressed habitats remain uncertain.
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Contaminants; Productivity; Habitat

Annual movement patterns of American common eiders Somateria mollissima dresseri - Mallory, M. L.; Ronconi, R. A.; Allen, R. B.; Dwyer, C.; Lair, S.; Mallory, C. D.; McLellan, N. R.; Milton, G. R.; Parsons, G. J.; Savoy, L.; Tomlik, M. D. (WILDLIFE BIOLOGY, 2020)
The American common eider Somateria mollissima dresseri is a sea duck of coastal mid-Atlantic North America, and breeding colonies in the southern part of its range have been in decline. To better understand threats faced by the subspecies, we used satellite telemetry to track 46 ciders through their annual cycle in four years from three regions in the southern part of the range, to identify key locations and migratory corridors. Female eiders exhibited highly variable movement phenology within and among colonies, but coastal Maine and Massachusetts were consistent, important moulting areas for males and females from all breeding colonies. Most birds wintered in coastal waters around Cape Cod and Nantucket Sound, meaning that threats in this region (industrial development, disease outbreak, harvest) could have deleterious effects on much of the population.
Times Cited in Web of Science Core Collection: 6 Total Times Cited: 6 Cited Reference Count: 54
Keywords: migration; common eider; SURVIVAL; POPULATION; satellite telemetry; SCOTERS; HABITAT USE; sea duck; MORTALITY; GREENLAND; DECLINES; moulting; wintering; BOREALIS; NOVA-SCOTIA

Wood duck and hooded merganser breeding success in nest boxes in Ontario - Mallory, Mark L.; Taverner, Austin; Bower, Bill; Crook, Dale (Wildlife Society Bulletin, 2002)
Wood ducks (Aix sponsa) and hooded mergansers (Lophodytes cucullatus) are common breeders in nest boxes in eastern Canada, but few studies have compared the breeding biology of these northern nesting birds to that of birds nesting to the south in the United States. We studied the breeding success of these species nesting in boxes near Ottawa, Ontario, Canada between 1986-1999. For wood ducks, mean annual box occupancy was 69% and mean clutch size was 12 eggs, with 60% of eggs hatched in a typical year. For nests with at least one egg hatching, hatching success was 83%. For hooded mergansers, mean box occupancy was 10% and mean clutch size was 10 eggs, with 64% of eggs hatched in an average year. For successful nests, hatching success was 87%. For both species, fewer eggs were hatched in years when the nest-box breeding population laid higher numbers of eggs. Despite the fact that this nest-box population was located near the northern limit of the wood duck breeding range, our results suggest that the basic nesting parameters of this population were similar to those of populations farther south.
Keywords: Breeding Season; Productivity; Hooded Merganser; Lophodytes cucullatus

Influence of intraspecific competition and habitat quality on diurnal activity budgets of breeding common goldeneyes - Mallory, Mark L.; Walton, Russell A.; McNicol, Donald K. (Ecoscience, 1999)
We examined how female common goldeneyes (Bucephala clangula) allocated time to various activities throughout the breeding cycle, and how time allocation was influenced by habitat quality (presence of fish competitors) and intraspecific competition. Before incubation and during incubation recesses, females spent 73% or more of observed time foraging, but brood defence became the dominant behaviour during brood-rearing (43%). Females preferentially used lakes with few or no fish at all stages of the breeding cycle. Females sharing lakes with other goldeneyes spent significantly more time alert, in social interactions, and diving for food, and less time resting than females occupying lakes solely with their mate. Our results show that the amount of time female goldeneyes spend in various activities may be determined primarily by their metabolic requirements at each stage of breeding, but that habitat quality and intraspecific competition also influence how females allocate their time.
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye; Habitat

Trace elements in marine birds, Arctic hare and ringed seals breeding near Qikiqtarjuaq, Nunavut, Canada - Mallory, Mark L.; Wayland, Mark; Braune, Birgit M.; Drouillard, Ken G. (Marine Pollution Bulletin, 2004)
Keywords: Breeding Season; Common Eider; Contaminants; Somateria mollissima

Effects of Nest Parasitism and Nest Location on Eggshell Strength in Waterfowl - Mallory, M. L.; Weatherhead, P. J. (Condor, 1990)
We examined the relationship between brood parasitism, nest location, egg shape, and eggshell thickness in waterfowl species. We found that within and across tribes, parasitic species did not have significantly rounder eggs or thicker shells than nonparasitic species. However, cavity-nesting species have both rounder eggs and thicker eggshells than open-nesting species. Cavity-nesting waterfowl may require stronger eggs because they often nest in sites that are too small or are irregularly shaped, thereby increasing the jostling of eggs against one another when the female enters or exits the nest. Using data for the Hooded Merganser (Lophodytes cucullatus), the species with the roundest egg and the proportionally thickest shell of all extant waterfowl, we found no evidence for a cost of increased eggshell strength, at least with regard to incubation period and egg hatchability. We also were unable to explain why Hooded Mergansers lay eggs like billiard balls.
Keywords: Breeding Season; Physiology; Hooded Merganser; Lophodytes cucullatus

Observer effects on common goldeneye nest defense - Mallory, Mark L.; Weatherhead, Patrick J. (Condor, 1993)
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye; Techniques

Incubation rhythms and mass loss of common goldeneyes - Mallory, Mark L.; Weatherhead, Patrick J. (Condor, 1993)
We examined simultaneously incubation rhythms and mass loss of 16 female Common Goldeneyes (Bucephala clangula). On average, female goldeneyes spent 81% of the day incubating eggs, and took 2.7 recesses per day, each lasting an average of 114 min. Females began incubation approximately 20% heavier than the lowest body mass they reached over the incubation period, a slightly greater mass loss than predicted for ducks their size. Goldeneye incubation behaviors were similar to those reported for other Mergini, and were consistent with the general relationship between body size and incubation behavior in waterfowl. Females differed in how they varied their incubation behavior in response to incubation patterns on the previous day and environmental factors, although females typically responded to warmer temperatures by spending more time off the nest. Female goldeneyes appeared to manage their mass loss by modifying their incubation behavior. Females tended to lose less mass on days following more substantial mass loss, and once females approached their minimum mass they spent more time off the nest. However, not all females were successful in this approach. Two females may have deserted their nests because they had relatively high mass loss ( gt 20%) and reached a low body mass (about 600 g), and thus could not maintain incubation sufficient to hatch their eggs without putting themselves at further risk.
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye; Energetics and Nutrition

Responses of nesting mergansers to parasitic common goldeneye eggs - Mallory, Mark L.; Weatherhead, Patrick J. (Animal Behaviour, 1993)
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye; Hooded Merganser; Lophodytes cucullatus

Nest site selection by common goldeneyes in response to habitat features influenced by acid precipitation - Mallory, Mark L.; Weatherhead, Patrick J.; McNicol, Donald K.; Wayland, Mark E. (Ornis Scandinavica, 1993)
The choice of nest sites is an important component of breeding behavior because it can influence reproductive success. We examined the effects of habitat quality on nest site selection by Common Goldeneyes Bucephala clangula in an acid-stressed area near Sudbury, Ontario. Females used fishless wetlands more often prior to incubation, and nested more frequently in nest boxes erected on these wetlands. Within fishless wetlands, female goldeneyes preferred boxes on wetlands that were more isolated from other waterbodies. We conclude that goldeneyes selected high quality, fishless wetlands because these habitats provide an abundant supply of invertebrate foods needed for reproduction.
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye; Contaminants; Habitat

Birds of the east James Bay coast between Long Point and Cape Jones - Manning, T. H.; MacPherson, A. H. (Canadian Field Nat, 1952)
A list of birds is presented based on observations and collections made between June 26 and Sept. 2, 1950, along the e. James Bay coast between Long Point and Cape Jones, Canada. The topography and vegetation of the main collecting stations are described. Detailed data are given on population densities of the following spp. Common Loon, Gavia i. immer; Black Duck, Anas rubripes; Hudson Bay Eider, Somateria mollissima sedentaria; White-winged Scoter, Melanitta deglandi; Surf Scoter, Melanitta perspicillata; American Scoter, Oidemia nigra americana; American Merganser, Mergus merganser americanus, and Red-breasted Merganser, Mergus serrator serrator; Osprey, Pandion haliaetus carolinensis; Ungava Willow Ptarmigan, Lagopus 1. ungavus; Greater Yellow-legs, Totanus melanoleucas; Herring Gull, Larus argentatus smithsonianus; Arctic Tern, Sterna paradisaea; Nearctic Mandt's Guillemot, Cepphus grylle ultimus; Northern Horned Lark, Eremophila a. alpestris; Labrador Jay, Perisoreus canadensis nigricapillus; Black-backed Robin, Turdus migratorius nigrideus; Eastern Ruby-crowned Kinglet, Regulus c. calendula: American Pipit, Anthus spinoletta rubescens; Northern Yellow Warbler, Dendroica petechia amnicola; Eastern Myrtle Warbler, Dendroica c. coronata; Common Redpoll, Acanthis f. flammea; Churchill Savannah Sparrow, Passerculus sandwichensis oblitus; Slate-coloured Junco, Junco h. hyemalis; Eastern Tree Sparrow, Spizella a. arborea; White-crowned Sparrow, Zonotrichia 1. leucophrys; White-throated Sparrow, Z. albtcollis; Eastern fox Sparrow, Passerella i. iliaca; and Lincoln's Sparrow, Melospiza 1. lincolnii. || ABSTRACT AUTHORS: H. A. Senn
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General

Evaluation of Rapid Antigen Detection Kits for the Diagnosis of Highly Pathogenic Avian Influenza H5N1 Infection - Marche, Sylvie; van den Berg, Thierry (Avian Diseases, 2010)
Early detection of highly pathogenic (HP) strains of avian influenza, especially the HP H5N1, is important in terms of controlling and minimizing the spread of the virus. Several rapid antigen detection kits that are able to detect influenza A viruses in less than 1 hr are commercially available, but only a few of them have been evaluated. In this study, four commercially available rapid tests for veterinary usage and two tests for human usage were evaluated and compared. The evaluation of the detection limits of the different tests established with serial dilution of HP H5N1 indicated that most of them have a detection limit of about 10(5) to 10(6) 50% tissue culture infectious dose/ml. None of the tests was able to detect virus in oral and cloacal swabs 24 hr post-experimental infection of specific-pathogen-free chickens with HP H5N1. However, 48 hr postinfection, almost all of the rapid tests were able to detect infected birds (dead or alive). Moreover, organs were also successful samples for detection of H5N1 with the rapid tests. Unexpectedly, the specificity was not very high for some tests. However, in general in this study, the tests for veterinary usage showed better sensitivity. To conclude, these tests offer good indicative value in the event of an outbreak, but as a result of their low sensitivity and some aspecific reactions, test results always need to be confirmed by other methods.
Keywords: Sea Ducks - General; Techniques; Disease

Bycatch of seabirds in the Polish part of the southern Baltic Sea in 1970-2018: a review - Marchowski, D. (ACTA ORNITHOLOGICA, 2021)
Bycatch, the unintended capture of animals other than target fish, is one of the most important anthropogenic threats to seabirds worldwide. This problem has been relatively little studied, however. The southern Baltic Sea is one of the three areas worldwide with the highest gillnet bycatch. Forty-eight publications from the years 1982-2021 addressing the problem of seabird bycatch in the Polish Exclusive Economic Zone (PEEZ) of the Baltic Sea were analysed for the purposes of this paper. Twenty-eight bird species were identified in bycatch, 13 of which have threatened or near-threatened status on the European Red Bird List. The magnitude of the annual bycatch was estimated for three periods: 1970s - 47,000 birds, 1980s and 1990s - 39,800 and 2010s - 21,300 birds. The most frequently bycaught species in the 2010s were Long-tailed Duck Clangula hyemalis (9,000 ind. yearly), Greater Scaup Aythya marila (3,500) and Velvet Scoter Melanitta fusca (2,000). Acceptable mortality thresholds calculated using both the Potential Biological Removal (PBR) and the BirdLife International (BLT) methods were found to have been exceeded: for Long-tailed Duck by 175% (PBR) and by 1,061% (BLT); for Greater Scaup by 542% (PBR) and by 3,400% (BLT); for Velvet Scoter by 35% (PBR) and by 495% (BLT). All three species are listed as Vulnerable in Europe. Six distinct bycatch areas have been identified in the PEEZ. Bycatch mitigation is exceedingly difficult to implement: the only effective method currently employed to protect seabirds from bycatch in gillnets involves the temporary closure of bird hotspots to gillnet fishing.
Times Cited in Web of Science Core Collection: 1 Total Times Cited: 1 Cited Reference Count: 101
Keywords: Long-tailed Duck; GILLNET FISHERIES; MERGUS-MERGANSER; LONGLINE; ACUARIIDAE; bycatch estimation; conservation implications; DUCKS SUBFAMILY ANATINAE; fishery; Greater Scaup; MELANITTA-FUSCA; MITIGATION; SCAUP AYTHYA-MARILA; STOMACH NEMATODES; threshold values; Velvet Scoter; waterbird bycatch; WILD DUCKS

The dominant species of piscivorous bird does not adversely affect fishery in the lagoons of the southern Baltic Sea - Marchowski, D.; Flis, A.; Gwiazda, R.; Kavetska, K. M.; Wysocki, D. (EUROPEAN ZOOLOGICAL JOURNAL, 2022)
The impact of fish-eating birds on fishery has long been debated. It is therefore important that the arguments in this debate be scientifically based. The Great Cormorant Phalacrocorax carbo is a flagship example of a conflict species that has been well studied. In some areas, however, such as the southern Baltic estuarine lagoons, the Goosander Mergus merganser may be more abundant, exerting a potentially greater impact on fisheries. However, this aspect has not been well studied in this region, so this article is an attempt to fill this knowledge gap. Based on the digestive tract content of 23 Goosander drowned in gillnets in Poland, it was found that the most frequently consumed species was Ruffe Gymnocephalus cernua (70% of biomass), followed by Zander Sander lucioperca (13% of biomass), Perch Perca fluviatilis (9% of biomass) and Roach Rutilus rutilus (8% of biomass). Average Goosander numbers in the Vistula and Odra estuaries in 2011-2018 were 11,000 in winter, 4,500 in spring and 2,800 in autumn. These fish-eating ducks were found to consume 242 t of fish annually during this period, whereas at the same time fishermen caught an average of 4,400 t of fish. The species caught by both Goosander and fishermen were mainly Zander (32 t vs 189 t), Perch (21 t vs 668 t) and Roach (19 t vs 701 t). No negative impact of Goosander foraging in the winter preceding the fishery season was demonstrated for any of the above species (Zander R-2 = 0.022; Perch R-2 = 0.834; Roach R-2 = 0.881).
Times Cited in Web of Science Core Collection: 0 Total Times Cited: 0 Cited Reference Count: 60
Keywords: PATTERNS; GILLNET FISHERIES; BEHAVIOR; PREDATION; WILD DUCKS; fish consumption; fish resources; Fish-eating birds; GOOSANDERS MERGUS-MERGANSER; marine habitat; Perch; Roach; Ruffe; SERRATOR; social conflict; wintering area; Zander

Waterbird counts on large water bodies: comparing ground and aerial methods during different ice conditions - Marchowski, D.; Jankowiak, L.; Lawicki, L.; Wysocki, D. (PEERJ, 2018)
The aerial and ground methods of counting birds in a coastal area during different ice conditions were compared. Ice coverage of water was an important factor affecting the results of the two methods. When the water was ice-free, more birds were counted from the ground, whereas during ice conditions, higher numbers were obtained from the air. The first group of waterbirds with the smallest difference between the two methods (average 6%) contained seven species: Mute Swan Cygnus olor, Whooper Swan Cygnus cygnus, Greater Scaup Aythya manila, Tufted Duck Aythya fuligula, Common Goldeneye Bucephala clangula, Smew Mergellus albellus and Goosander Mergus merganser; these were treated as the core group. The second group with a moderate difference (average 20%) included another six species: Mallard Anas platyrhynchos, Eurasian Wigeon Mareca penelope, Common Pochard Aythya ferina, Great Crested Grebe Podiceps cristatus and Eurasian Coot Fulica atra. The third group with a large difference (average 85%) included five species, all of the Anatini tribe: Gadwall Mareca strepera, Northern Pintail Anas acuta, Northern Shoveler Spatula clypeata, Eurasian Teal Anas crecca and Garganey Spatula querquedula. During ice conditions, smaller numbers of most species were counted from the ground. The exception here was Mallard, more of which were counted from the ground, but the difference between two methods was relatively small in this species (7.5%). Under ice-free conditions, both methods can be used interchangeably for the most numerous birds occupying open water (core group) without any significant impact on the results. When water areas are frozen over, air counts are preferable as the results are more reliable. The cost analysis shows that a survey carried out by volunteer observers (reimbursement of travel expenses only) from the land is 58% cheaper, but if the observers are paid, then an aerial survey is 40% more economical.
Times Cited in Web of Science Core Collection: 6 Total Times Cited: 7 Cited Reference Count: 43
Keywords: BIRDS; Baltic Sea; Waterfowl; ACCURACY; Accuracy of population estimates; Costal lagoons; Ducks; VISIBILITY BIAS; Wintering

Ducks change wintering patterns due to changing climate in the important wintering waters of the Odra River Estuary - Marchowski, D.; Jankowiak, L.; Wysocki, D.; Lawicki, L.; Girjatowicz, J. (PEERJ, 2017)
Some species of birds react to climate change by reducing the distance they travel during migration. The Odra River Estuary in the Baltic Sea is important for wintering waterfowl and is where we investigated how waterbirds respond to freezing surface waters. The most abundant birds here comprise two ecological groups: bottom-feeders and piscivores. Numbers of all bottom-feeders, but not piscivores, were negatively correlated with the presence of ice. With ongoing global warming, this area is increasing in importance for bottom-feeders and decreasing for piscivores. The maximum range of ice cover in the Baltic Sea has a weak and negative effect on both groups of birds. Five of the seven target species are bottom-feeders (Greater Scaup Aythya marila, Tufted Duck A. fuligula, Common Pochard A. ferina, Common Goldeneye Bucephala clangula and Eurasian Coot Fulica atra), and two are piscivores (Smew Mergellus albellus and Goosander Mergus merganser). Local changes at the level of particular species vary for different reasons. A local decline of the Common Pochard may simply be a consequence of its global decline. Climate change is responsible for some of the local changes in the study area, disproportionately favoring some duck species while being detrimental to others.
Times Cited in Web of Science Core Collection: 14 Total Times Cited: 17 Cited Reference Count: 62
Keywords: Behavior; Baltic Sea; DIVING DUCKS; Greater Scaup; Common Pochard; Eurasian coot; Ice coverage sensitivity; Important Bird Areas; MIGRATORY BIRDS; Smew; Tufted Duck; Winter range shift

Management of Marine Natura 2000 Sites as Exemplified by Seabirds Wintering in the Baltic Sea: The Case of Poland - Marchowski, D.; Lawicki, L.; Kaliciuk, J. (DIVERSITY-BASEL, 2022)
Based on the example of wintering waterbirds in the Baltic Sea, we show an approach that is useful in defining priority species for management. The Value Factor (VF) is the quantitative method for evaluating the importance of an area for a species. Every year, 4,400,000 waterbirds winter in the Baltic. Among these, the highest priority species are velvet scoter Melanitta fusca (hereafter VS, VF = 153) and long-tailed duck Clangula hyemalis (hereafter LTD, VF = 204): 74% and 40%, respectively, of the world's populations, and over 90% of the EU populations of both species spend the winter in the Baltic. Management plans (hereafter MP) regulating the protection of marine Natura 2000 sites (hereafter MPA) and dedicated to the protection of VS and LTD have been implemented in 65% and 51%, respectively, of MPAs in the Baltic. Poland, a key country for the survival of these species, has not implemented a single MP despite the existence of documentation confirming their crucial importance for seaducks, and the pressures occurring there. We suggest using the VF concept to define priority species. On this basis, it will be possible to identify gaps in the protection of the most seriously threatened species and implement conservation measures at the most appropriate sites.
Times Cited in Web of Science Core Collection: 0 Total Times Cited: 0 Cited Reference Count: 48
Keywords: long-tailed duck; POPULATION; CONSERVATION; BYCATCH; GILLNET FISHERIES; BIODIVERSITY LOSS; biodiversity strategy; management of threatened species; Natura 2000; seaducks; THREATS; velvet scoter

Warmer winters increase the breeding success of the Goosander in the Pomeranian Lake District in Poland - Marchowski, D.; Mohr, A.; Lawicki, L.; Jankowiak, L. (ARDEA, 2022)
Northern Hemisphere species generally respond to global warming by withdrawing from the southern margins of their distributions and shifting their breeding sites northwards. However, the situation regarding the breeding populations of Goosanders Mergus merganser merganser in Europe appears to be paradoxical: in many places, an increase in the breeding population and range extension have been documented. We studied the breeding biology of this species during the breeding seasons of 1987-1996. We show that the breeding success of a Goosander population breeding in Northern Poland was higher following winters when the ice cover disappeared earlier. There was a significant positive relationship between the disappearance of ice cover and the clutch initiation date, and the breeding success of early broods was higher. The overall mean clutch initiation date was 13 April +/- 15 days (SD). The yearly means of clutch initiation dates varied from the beginning of April to the beginning of May. It seems likely that, among other factors, the Goosander's adaptability in terms of the timing of breeding may be partially responsible for the expansion of the species into new areas in the last 30 years.
Times Cited in Web of Science Core Collection: 1 Total Times Cited: 1 Cited Reference Count: 63
Keywords: BIRDS; POPULATION; SHIFTS; MERGUS-MERGANSER; adaptive capacity of species; breeding performance; Central Europe; human pressure; ice cover; SALMON

Research on long-term colonization of goosander (Mergus merganser Linneaus, 1758) with reference to habitat availability - Marinkovic, S. P.; Skoric, S. B.; Popovic, Zorica S.; Nikcevic, M. V. (Archives of Biological Sciences, 2008)
This article presents data on long-term colonization of goosander in Western Serbia and Eastern Republic of Srpska (on five oligotrophic reservoirs formed by the Drina River) based on continuous counting since the first observation of nesting in 1987. The total number of breeding pairs and their distribution in neighboring habitats continuously increased from year to year, suggesting that expansion of the population is still below the limit of the habitat. The decrease in population which occurred in certain years was due to environmental or anthropogenic influence.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Common merganser; Mergus merganser

Variation in the abundance of red-breasted mergansers Mergus serrator on a Scottish river in relation to season, year, river hydrography, salmon density and spring culling - Marquiss, Mick; Duncan, Keith (Ibis, 1993)
Red-breasted Mergansers Mergus serrator were counted in the river North Esk, Scotland (UK), and on the sea nearby, 1987-1990. Pairs arrived at the river estuary from early winter, but the main influx to freshwater took place in late April and in May, when breeding pairs dispersed far upriver. Females began incubation from late May. Most young hatched in July and fledged by late September. Males left the river in June and congregated at an offshore moulting site, their numbers peaking in August, and dispersed rapidly in September. Breeding density and total duckling production decreased with incresing distance up-stream, decreasing river width and increasing gradient and elevation. The total number of breeding pairs and their distribution on the river were similar from year to year, despite variable numbers killed, suggesting a stable breeding population near the upper limit the habitat would support in those years. It also suggested that killing mergansers in April was an ineffective way to reduce the population. The spatial variation in merganser breeding density was not correlated with the density of their main spring food, parr of salmon Salmo salar, but could have been related to its availability. The production of well-grown ducklings varied annually and was inversely correlated with river flow during the main period of hatch. It is argued that Red-breasted Mergansers breed late in the year because the hatching of ducklings in July coincides with an abundance of their food, large aquatic invertebrates and tiny juvenile fish.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Productivity; Mergus serrator; Red-breasted merganser

Diurnal activity patterns of Goosanders Mergus merganser on a Scottish river system - Marquiss, M.; Duncan, K. (Wildfowl, 1994)
Goosanders were counted as they, arrived and departed from overnight communal roosts. All birds left the roost before sunrise and returned from 50 minutes prior to, until 10 minutes after sunset. Relative to sunset, they arrived later on short midwinter days, and earlier on the longer days of February and March. Goosanders did not roost communally from April to August, except in May, in an area where males gathered prior to their leaving to moult. The diurnal behaviour of Goosanders, quantified using three methods, showed that most of the daytime was spent foraging and loafing. Foraging peaked in the first two hours of the day, decreasing thereafter for adults, less so for birds in their first winter, and least for ducklings. Calculations of total daily foraging times suggested adults fed for 34 hours, Young birds for 5-6 hours and duckling.,; for about 10 hours. Total time spent flying could not be estimated accurately, though there was significant seasonal variation in the frequency with which it was recorded. Other behavioural activities included social interaction which was overt as birds gathered to roost, suggesting communal roosting provided an important venue for pair-formation.
Keywords: Behavior; Nonbreeding Seasons; Common merganser; Mergus merganser

Seasonal switching between habitats and changes in abundance of Goosanders Mergus merganser within a Scottish river system - Marquiss, M.; Duncan, K. (Wildfowl, 1994)
Systematic weekly counts during 1988, in five wetland habitats within the Dee watershed, showed that Goosanders were most abundant on the upper river in spring and summer, on the lower river in late summer, autumn and winter, and on lochs in late winter and spring. Many birds were in pairs in winter and spring, but adult males were absent from June to October, when the population was successively dominated by females, then females with broods, then juveniles. Most females nested for tip tributaries and moved downstream with small ducklings to nursery areas on the main stem Once grown, juveniles possibly moved downstream again before they dispersed from the watershed. Counts on a sample of river sections in mid-April quantified a strong inverse relationship between Goosander density and elevation, and the total population then was estimated to be 173 (including about 61 pairs). A census of the whole river in July estimated a population of 278 birds (including 32 broods) and in December, 66 birds. It is argued that the use of various habitats was associated with food availability, security from predators, pairing and nesting.
Keywords: Breeding Season; Nonbreeding Seasons; Dispersal; Common merganser; Mergus merganser; Habitat

Growth rate and influence of predation risk on territoriality in juvenile coho salmon (Oncorhynchus kisutch) - Martel, Guy (Canadian Journal of Fisheries and Aquatic Sciences, 1996)
Juveniles of species in which size influences survival should be selected to optimize their growth rate. Although the defense of feeding territories is a common foraging tactic among stream-dwelling salmonids, the direct benefits of territoriality in terms of growth rate have seldom been demonstrated in these fish. I followed individually marked juvenile coho salmon, Oncorhynchus kisurch, for 3 months in field enclosures. Territorial fish grew faster than nonterritorial fish (floaters) confined to the same area. Territorial juveniles face a growth mortality trade-off when predators are present, since the movements associated with territorial defense may increase their risk of being detected by predators. When piscivorous birds (common mergansers, Mergus merganser) were present upstream, territorial coho rarely left their territories, but did decrease the average duration of their aggressive interactions and movements, and the total amount of time they devoted to territorial activities and to moving. Some fish also allowed intruders to approach more closely before intercepting them. There were, however, no effects attributable to the frequency at which fish were exposed to a predator.
Keywords: Trophic Interactions; Common merganser; Mergus merganser

Feeding and aggressive behaviours in juvenile coho salmon (Oncorhynchus kisutch) under chemically-mediated risk of predation - Martel, Guy; Dill, Lawrence M. (Behavioral Ecology and Sociobiology, 1993)
Juvenile coho salmon (Oncorhynchus kisutch) spend the first year of their lives in their natal streams, where they may often hold feeding territories. They also face significant risk of predation by birds and fish, and should alter their behaviour to reduce risk of mortality when these predators are present. Although there is laboratory evidence that coho react to predator visual stimuli, chemoreception of avian predator presence has not previously been reported. We tested the influence of chemical stimuli of common merganser (Mergus merganser), preying on juvenile coho, on two aspects of coho territorial behaviour, foraging and aggression, in flow-through aquaria. After a mixture of merganser- and coho-conditioned water was introduced into the system, juvenile coho significantly reduced their attack distance on drifting prey. The fish also significantly decreased their aggressive behaviour directed towards mirrors (total number of acts, intensity of acts and time spent) when the same odour was present. They did not change their behaviour in either experiment after control introductions of water treated with fish alone. These results are interpreted within the framework of a trade-off between juvenile growth and mortality.
Keywords: Trophic Interactions; Common merganser; Mergus merganser

Influence of Movement of Coho Salmon (Oncorhynchus kisutch) Parr on Their Detection by Common Mergansers (Mergus merganser) - Martel, Guy; Dill, Lawrence M. (Ethology, 1995)
A common reaction in juvenile salmonids that detect predators is to decrease activity. To test whether there is a survival advantage to reduced movement under such circumstances, juvenile coho salmon (Oncorbynchus kisutch) were placed with common mergansers (Mergus merganser) under laboratory conditions that precluded crypsis. Mergansers were more likely to attack fish that moved than fish that remained stationary, and the relation between the lag time for detection by the birds and fish movement rate is best described as inversely exponential. The lag time for detection was not correlated with fish size. The risk of detection of prey by visual predators should be determined by both predator and prey behaviour, but our results suggest that in this case prey behaviour is more important. In the field, territorial coho juveniles do feed more and grow faster than other, nonterritorial fish. They also spend a smaller proportion of their time moving. The present experiment suggests that territorial coho may also suffer less mortality than non-territorial fish, which would lower their ratio of mortality risk to growth rate.
Keywords: Trophic Interactions; Common merganser; Mergus merganser

Distribution and movements of Alaska-breeding Steller's Eiders in the nonbreeding period - Martin, P. D.; Douglas, D. C.; Obritschkewitsch, T.; Torrence, S. (Condor, 2015)
Steller's Eiders (Polysticta stelleri) that breed in Alaska, USA, are listed as threatened under the U.S. Endangered Species Act (ESA), yet the degree to which these individuals segregate during the nonbreeding period from conspecifics that nest in Russia is unknown. Likewise, very little is known about the timing of use and distribution of autumn migration routes, stopover sites, and molting and wintering areas by the Alaska-breeding population. To address this information need, we implanted 14 Steller's Eiders with satellite transmitters in 2000 and 2001 at their primary Alaskan breeding grounds near Barrow. We found no evidence for segregation of the Alaska-breeding population in midwinter because locations were well-distributed along the Alaska Peninsula, congruent with prevailing knowledge about the wintering distribution of Steller's Eiders that breed in Russia. During the wing molt, from late August to early October, 7 of 13 individuals used Kuskokwim Shoals, corroborating the importance of this area and its designation as critical habitat under the ESA. Steller's Eiders are generally described as preferring shallow waters <10 m deep, but our winter tracking data clearly documented occupancy of deeper offshore waters. Steller's Eiders frequently used up to 30-m deep water almost exclusively at night during winter. We speculate that nighttime occupancy of deeper water habitats may be for resting and/or for consumption of zooplankton species, such as euphausiids, that are abundant and well known for their nocturnal vertical migrations in the water column.
Martin, Philip D. Douglas, David C. Obritschkewitsch, Tim Torrence, Shannon
Keywords: Molt; Migration; Habitat; Nonbreeding season; Polysticta stelleri; Steller’s Eider

Natural hybrids between the Common Goldeneye, Bucephala clangula, and barrow's Goldeneye, B. islandica - Martin, Paul R.; Di Labio, Bruce M. (Canadian Field-Naturalist, 1994)
Most records of hybrid Common times Barrow's goldeneyes are of male alternate-plumaged birds, probably reflecting bias with respect to identification and possibly a greater abundance of hybrids in this plumage. The male alternate plumage is the only hybrid plumage to be acceptably described. Hybrids in this plumage appear fairly uniform as a group, exhibiting intermediate characteristics between the two parent species. Hybrid records are geographically widespread, originating from all three distinct regions of overlap. An increase in the number of hybrid records in the past 40 years is obscured by an increase in the number of observers in the field, as well as improved optical equipment. Despite these biases, a recent increase in the incidences of hybridization in British Columbia may exist.
Keywords: Taxonomy; Bucephala clangula; Common Goldeneye; Barrow's Goldeneye; Bucephala islandica

Barriers to movement: impacts of wind farms on migrating birds - Masden, Elizabeth A.; Haydon, Daniel T.; Fox, Anthony D.; Furness, Robert W.; Bullman, Rhys; Desholm, Mark (ICES Journal of Marine Science, 2009)
Advances in technology and engineering are enhancing the contribution that wind power makes to renewable energy generation. Wind farms, both operational and in planning, can be expected to impact negatively on wildlife populations, particularly birds. We propose a novel approach to assess the impacts through the energetic costs of avoidance behaviour for a long-distance, migratory seaduck. Flight trajectories were recorded using surveillance radar at a Danish offshore wind farm with emphasis placed on the 200 000+ migrating common eiders that pass through the area annually. Minimum distance to wind farm and curvature of trajectories were compared pre- and post-construction. Additional costs of the avoidance response were estimated using an avian energetic model. The curvature of eider trajectories was greatest post-construction and within 500 m of the wind farm, with a median curvature significantly greater than pre-construction, suggesting that the birds adjusted their flight paths in the presence of the wind farm. Additional distance travelled as a consequence of the wind farm's presence was ca. 500 m and trivial compared with the total costs of a migration episode of 1400 km. However, construction of further wind farms along the migration route could have cumulative effects on the population, especially when considered in combination with other human actions.
Keywords: Conservation; Common Eider; Nonbreeding Seasons; Migration; Somateria mollissima; Energetics and Nutrition

Assessing the impact of marine wind farms on birds through movement modelling - Masden, E. A.; Reeve, R.; Desholm, M.; Fox, A. D.; Furness, R. W.; Haydon, D. T. (Journal of the Royal Society Interface, 2012)
Times Cited: 3 Masden, Elizabeth A. Reeve, Richard Desholm, Mark Fox, Anthony D. Furness, Robert W. Haydon, Daniel T. Fox, Anthony/I-7465-2013; Desholm, Mark/J-5980-2013 4
Keywords: Conservation; Nonbreeding Seasons; Migration; Somateria mollissima; Common eider

Metal concentrations in oldsquaw (Clangula hyemalis) during an outbreak of avian cholera, Chesapeake Bay, 1994 - Mashima, Ted Y.; Fleming, W. James; Stoskopf, Michael K. (Ecotoxicology, 1998)
Forty out of 41 oldsquaw carcasses collected during a 3 month avian cholera outbreak in Chesapeake Bay, USA, in 1994 were culture positive for Pasteurella multocida. Pasteurella-positive birds collected in February had greater (p ltoreq 0.05) mean (geometric) liver concentrations of cadmium (7.35 versus 3.71 mug per g dry weight) and lower concentrations of selenium (9.90 versus 12.5 mug per g dry weight) than Pasteurella-positive birds collected during March and April. The mercury content of the livers and cadmium content of the kidneys did not differ (p > 0.05) between birds collected early in the die-off and those collected in March and April. The liver and kidney concentrations of metals in the Pasteurella-positive birds collected in 1994 were compared to apparently healthy oldsquaw (n = 67) collected from Chesapeake Bay during 1985-1987, because healthy oldsquaw were not collected during the avian cholera outbreak in 1994. Compared to the apparently healthy oldsquaw collected in 1985-1987, the mean concentrations of cadmium (liver 4.32 versus 2.65 mug per g dry weight and kidney 22.7 versus 11.5 mug per g dry weight) were greater (p ltoreq 0.05) in the oldsquaw which succumbed to avian cholera in 1994. In contrast, the liver concentrations of selenium (11.9 versus 17.8 mug per g dry weight) and mercury (0.389 versus 1.83 mug per g dry weight) were lower (p ltoreq 0.05) in the birds from the 1994 die-off than for the apparently healthy oldsquaw collected in 1985-1987. Three birds from the 1985-1987 cohort and none of the birds from the 1994 cohort had liver lead concentrations greater than 4 mug per g dry weight. The results of this study indicate a possible link between high cadmium tissue concentrations and susceptibility to avian cholera in oldsquaw.
Keywords: Nonbreeding Seasons; Clangula hyemalis; Long-tailed Duck; Contaminants; Disease

Numbers of wintering waterbirds on rivers in eastern England - Mason, Chris F.; Macdonald, Sheila M. (Wildfowl, 2000)
Waterbirds were counted on three occasions during the winter of 1999-2000 on 22 1-km reaches of river in north Essex and south Suffolk, eastern England. Fourteen species were recorded but only five were frequent: Little Grebe (Tachybaptus ruficollis), Mute Swan (Cygnus olor), Mallard (Anas platyrhynchos), Moorhen (Gallinula chloropus), and Coot (Fulica atra). Mallard was the most numerous species. All five species except Little Grebe congregated at places where they were fed by the public. Only Little Grebe showed an increase in numbers over the winter. Of eight habitat variables measured, only river width was consistently related positively, to waterbird numbers. Despite low densities, it is estimated that riverine populations of Little Grebe, Mute Swan, Mallard and Moorhen in the study area are likely to be larger overall than those on the main reservoirs and estuaries in the catchment.
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons; Common merganser

At-sea distribution and abundance of seabirds off southern California: A 20-year comparison - Mason, John W.; McChesney, Gerard J.; McIver, William R.; Carter, Harry R.; Takekawa, John Y.; Golightly, Richard T.; Ackerman, Joshua T.; Orthmeyer, Dennis L.; Perry, William M.; Yee, Julie L.; Pierson, Mark O.; McCrary, Michael D. (Studies in Avian Biology, 2007)
We conducted aerial at-sea and coastal surveys to examine the distribution and abundance of seabirds off southern California, from Cambria, California, to the Mexican border. From May 1999-January 2002, we flew 102 d, covered > 54,640 km of transect lines, and conducted nine complete surveys of southern California in January, May, and September. We identified 54 species comprising 12 families and counted > 135,000 individuals. Seabird densities were greater along island and mainland coastlines than at sea and were usually greatest in January surveys. Densities were greatest at sea near the northern Channel Islands in January and north of Point Conception in May, and lowest in the southwestern portion of the Southern California Bight in all survey months. On coastal transects, seabird densities were greatest along central and southern portions of the mainland coastline from Point Arguello to Mexico. We estimated that 981,000 +/- 144,000 ((x) over bar +/- SE) seabirds occurred in the study area in January, 862,000 95,000 in May, and 762,000 72,000 in September. California Gulls (Larus californicus), Western Grebes (Aechniophorus occidentalis), and Cassin's Auklets (Ptychoramphus aleuticus) were most abundant in January surveys at sea, whereas Sooty and Short-tailed shearwaters (Puffinus griseus and P. tenuirostris), phalaropes (Phalaropus spp.), and Western Gulls (Larus. occidentalis) were most abundant in May and September surveys. On coastal transects, California Gulls, Western Grebes, Western Gulls, and Surf Scoters (Melanitta perspicillata) were most abundant in January; Western Grebes, Western Gulls, Surf Scoters, and Brown Pelicans (Pelecanus occidentalis) were most abundant in May; and Sooty Shearwaters, Short-tailed Shearwaters, Western Gulls, Western Grebes, Brown Pelicans, and Heermann's Gulls (Larus heermanni) were most abundant in September. Compared to historical seabird densities collected in the same area two decades ago (1975-1978 and 1980-1983), abundance was lower by 14% in January, 57% in May, and 42% in September. Common Murres (Uria aalge, >= 75% in each season), Sooty Shearwaters, (55% in May, 27% in September), and Bonaparte's Gulls (L. philadelphia, >= 95% in each season) had lower densities. Conversely, Brown Pelicans (167% overall), Xantus's Murrelets (Synthliboramphus hypoleucus; 125% overall), Cassin's Auklets (100% overall), Ashy Storm-Petrels (Oceanodroma homochroa, 450% overall) and Western Gulls (55% in May), and Brandt's Cormorants (Phalacrocorax penicillatus, 450% in September) had greater densities. Our results indicate that seabird abundance has declined off the southern California coast in the past two decades, and these declines may be warning signs of environmental degradation in the region or effects of larger forces such as climate change.
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons

A new duck circovirus sequence, detected in velvet scoter (Melanitta fusca) supports great diversity among this species of virus - Matczuk, A. K.; Krawiec, M.; Wieliczko, A. (Virology Journal, 2015)
Background: The aim of this study was to investigate the presence of circoviruses in wild bird populations, in Poland. Circoviruses possess immuno-suppressive properties and might interfere with the health of wild birds. Method: 83 birds, which belonged to 23 species, were tested with broad-range, nested PCR. The obtained PCR products were sequenced and new primers designed, to analyse the full-length, viral genome. A phylogenetic analysis was conducted, to find any relationship to known circoviruses. Results: The circovirus DNA sequence was found in 4 birds. All samples originated from the velvet scoter (Melanitta fusca) a marine duck from the Merginae sub-family. Birds which tested positive for the circovirus were found dead in fishing nets, off the Baltic coast. During post-mortem examination, carcasses of two of the scoters showed only light emaciation, while the two other birds appeared healthy. The obtained, full-length, circovirus sequence revealed 1,988 nucleotides and the presence of typical features (i.e. Cap, Rep and ORF3). Nucleotide similarity to other duck circoviruses was 84 to 86 %. Phylogenetic analysis of the complete genome and cap gene, indicated that the new circovirus is related to known duck circoviruses, especially to sub-types sometimes referred to as duck circovirus genotype 1, but not genotype 2. Conclusions: In this study, we have reported a new duck circovirus sequence detected in the velvet scoter, a species of marine duck. Sequence comparison and phylogenetic analysis of the new virus sequence support previous reports that duck circovirus (DuCV) is a species with a high degree of diversity. The viral sequence obtained from the velvet scoter suggests that DuCV may infect birds from the Anatinae sub-family. More studies are needed to prove if the velvet scoter and other marine ducks act as a reservoir for DuCV.
Matczuk, Anna Karolina Krawiec, Marta Wieliczko, Alina
Keywords: Melanitta fusca; White-winged Scoter; Disease

Evaluation of bursal depth as an indicator of age class of Harlequin Ducks - Mather, Danielle D.; Esler, Daniel (Journal of Field Ornithology, 1999)
We contrasted the estimated age class of recaptured Harlequin Ducks (Histrionicus histrionicus) (n = 255) based on bursal depth with expected age class based on bursal depth at first capture and time since first capture. Although neither estimated nor expected ages can be assumed to be correct, rates of discrepancies between the two for within-year recaptures indicate sampling error, while between-year recaptures test assumptions about rates of bursal involution. Within-year, between-year, and overall discrepancy rates were 10%, 24%, and 18%, respectively. Most (86%) between-year discrepancies occurred for birds expected to be after-third-year (ATY) but estimated to be third-year (TY). Of these ATY-TY discrepancies, 22 of 25 (88%) birds had bursal depths of 2 or 3 mm. Further, five of six between-year recaptures that were known to be ATY but estimated to be TY had 2 mm bursas. Reclassifying birds with 2 or 3 mm bursas as ATY resulted in reduction in between-year (24% to 10%) and overall (18% to 11%) discrepancy rates. We conclude that age determination of Harlequin Ducks based on bursal depth, particularly using our modified criteria, is a relatively consistent and reliable technique.
Keywords: Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Physiology; Techniques

Numbers and Distribution of Long-Tailed Wintering Ducks in Northern Europe - Mathiasson, S. (British Birds, 1970)
Keywords: Abundance, Distribution, and Trends; Nonbreeding Seasons; Clangula hyemalis; Long-tailed Duck

Evidence of chromosomal damage in common eiders (Somateria mollissima) from the Baltic Sea - Matson, Cole W.; Franson, J. Christian; Hollmen, Tuula; Kilpi, Mikael; Hario, Martti; Flint, Paul L.; Bickham, John W. (Marine Pollution Bulletin, 2004)
Common eiders nesting in the Baltic Sea are exposed to generally high levels of contaminants including potentially genotoxic polycyclic aromatic hydrocarbons and organochlorines. Blood samples were collected from eiders at eight sites in the Baltic Sea and two sites in the Beaufort Sea. DNA content variation was estimated using the flow cytometric method, and subsequently utilized as a biomarker of genetic damage. We observed no significant differences in genetic damage among populations within either the Baltic or Beaufort Seas. However, eider populations from the Baltic Sea had significantly elevated estimates of genetic damage compared to populations from the Beaufort Sea. Copyright 2004 Elsevier Ltd. All rights reserved.
Keywords: Breeding Season; Common Eider; Contaminants; Somateria mollissima

Environmental chemicals in eggs of Dunlins (Calidris alpina) from Northern Norway compared to eggs of coastal bird species breeding in the Wadden Sea - Mattig, Frank R.; Roesner, Hans-Ulrich; Giessing, Katrin; Becker, Peter H. (Journal fuer Ornithologie, 2000)
Owing to the international importance of the Wadden Sea for waders and waterfowl a long-term program to monitor chemical contamination of birds breeding in the Wadden Sea has been established in the early 1980s with Oystercatcher (Haematopus ostralegus) and Common Tern (Sterna hirundo) as monitor species. However, numbers of birds breeding in the area are only 10% compared to numbers of birds using it as a wintering, moulting or staging area, and little is known about contamination of those non-breeding birds. In 1993 we compared contamination levels in eggs from eight species (Shelduck Tadorna tadorna; Eider Somateria mollissima; Oystercatcher; Avocet Recurvirostra avosetta; Redshank Tringa totanus; Black-headed Gull Larus ridibundus; Herring Gull Larus argentatus; Common Tern) breeding at the island of Spiekeroog (German Wadden Sea) with those from Dunlins (Calidris alpina alpina) breeding in Northern Norway (Gamvik). It is known that many Dunlin from this area use the German Wadden Sea for staging. We analyzed contaminant levels of 21 industrial chemicals (PCBs, HCB, Moschusxylol, Octachlorstyrol, Mercury) and biocides (DDT and metabolites, HCH-Isomers, Bromocyclen). Common Tern and Herring Gull eggs reached highest SIGMA-PCB levels whereas mercury had the highest concentrations in eggs of Eider, Oystercatcher and Common Tern as well as SIGMA-DDT in eggs of Black-headed Gull. Bromocyclen could not be detected in eggs of the breeding species, whereas Moschusxylol was found in 29% of the eggs and Octachlorostyrol in 57%. Contaminant levels were in most cases above the levels given by German law for eggs used for human food but are probably not high enough to show an effect on the breeding success of the different species. In comparison to these results contaminant levels in eggs of Dunlins from Northern Norway were low and showed a similar chemical pattern as for migrating waders breeding in the Wadden Sea detected. For the first time Bromocyclen residues could be detected in bird eggs.
Keywords: Breeding Season; Common Eider; Contaminants; Somateria mollissima

Using radio-transmitters to improve estimates of gull predation on Common Eider ducklings - Mawhinney, K.; Diamond, A. W. (Condor, 1999)
We quantified the efficacy of using pellet numbers to estimate predation rates on Common Eider (Somateria mollissima) ducklings by Great Black-backed Gulls (Larus marinus) by using eider ducklings fitted with radio transmitters. Ducklings fitted with radio-transmitters were no more vulnerable to gull predation than were other ducklings. The recovery of radio-transmitters attached to eider ducklings and subsequently retrieved from Great Black-backed Gull pellets suggests that traditional methods of estimating the number of eider ducklings eaten by gulls from the remains found in pellets at gull nests and loafing areas underestimates the true number eaten by gulls by a factor of 5-17. Previous low estimates of eider duckling mortality on the Wolves Archipelago, Bay of Fundy cannot be explained by movements of broods to the mainland coast.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Techniques; Trophic Interactions

Ossification sequence of the avian order Anseriformes, with comparison to other precocial birds - Maxwell, Erin E. (Journal of Morphology, 2008)
Ossification sequences are poorly known for most amniotes, and yet they represent an important source of morphogenetic, phylogenetic, and life history information. Here, the author describes the ossification sequences of three ducks, the Common Eider Somateria mollissima dresseri, the Pekin Duck Anas platyrhynchos, and the Muscovy Duck Cairina moschata. Sequence differences exist both within and among these species, but are generally minor. The Common Eider has the most ossified skeleton prior to hatching, contrary to what is expected in a subarctic migrant species. This may be attributed to a tradeoff between growth rate and locomotory performance. Growth rate is higher in hatchlings with more cartilaginous skeletons, but this may compromise locomotion. No major ossification sequence differences were observed in the craniofacial skeleton when compared with Galliformes, which suggests that the influence of adult morphology on ossification sequence might be relatively minor in many taxa. Galliformes and Anseriformes, while both highly ossified at hatching, differ in the location of their late-stage ossification centers. In Anseriformes, these are most often located in the appendicular skeleton, whereas in Galliformes they are in the thoracic region and form the ventilatory apparatus.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Physiology

Water body type and group size affect the flight initiation distance of European waterbirds - Mayer, M.; Natusch, D.; Frank, S. (PLOS ONE, 2019)
Human encroachment on nature grows constantly, increasing human-wildlife interactions. Flight initiation distance (FID, the distance at which animals flee from an approaching threat) is often used to measure antipredator behaviour and establish buffer zones to reduce human impact on wildlife. In this study, we approached 10 waterbird species on larger lakes and narrower rivers using a motorboat. We investigated whether water body type, season (winter/spring), approach starting distance, species body mass, and group size influenced bird FID. Average bird FID was 145 +/- 92 m and differed between species. In general, FID of all species was larger on lakes than rivers and increased with increasing group size and approach starting distance. When analysed separately for the two most common species, common goldeneyes (Bucephala clangula) and mallards (Anas platyrhynchos), FID increased with increasing starting distance on rivers, but not lakes, likely because birds on lakes have enough time to evaluate the approaching object and take flight at great distance. Additionally, birds might perform different activities on lakes versus rivers, leading to varying energetic trade-offs between the two habitat types, which may affect the decision when to take flight. Finally, mallards aggregated in larger groups on lakes, which affected FID, likely due to enhanced visibility (i.e., earlier detection of the approaching boat) and detection probability (via increased group size) on lakes. Our results emphasize the importance of accounting for habitat characteristics, such as water body type, when studying waterbird FID, because they can affect the visibility of stimuli, group size and potentially animal behaviour, factors which should be taken into account when planning buffer zones for waterbirds in conservation areas.
Times Cited in Web of Science Core Collection: 13 Total Times Cited: 14 Cited Reference Count: 68
Keywords: BIRDS; EXPOSURE; RESPONSES; PREDATION RISK; WILDLIFE; HUMAN DISTURBANCE; BUFFER-ZONE DISTANCES; ESCAPE BEHAVIOR; FEAR; TOLERANCE

Dietary exposure to organic contaminants of waterfowl that consume zebra mussels - Mazak, E. J.; Macisaac, H. J. (American Zoologist, 1994)
Keywords: Nonbreeding Seasons; Bucephala clangula; Common Goldeneye; Contaminants

Influence of feeding habits on organochlorine contaminant accumulation in waterfowl on the Great Lakes - Mazak, Edward John; Macisaac, Hugh J.; Servos, Mark Roy; Hesslein, Ray (Ecological Applications, 1997)
Zebra mussels (Dreissena polymorpha) are an important component of benthic communities in the Great Lakes and are exploited by a host of predators, including waterfowl. In this study, we analyze diet content and stable isotope and organochlorine contaminant patterns in Lesser Scaup (Aythya affinis), Greater Scaup (Aythya marila), Bufflehead (Bucephala albeola), Redhead (Aythya americana), Canvasback (Aythya valisineria), and Mallard (Anas platyrhynchos) collected from three sites (Fighting Island, western Lake Erie, Big Creek) in the lower Great Lakes. Lesser and Greater Scaup from Fighting Island were classified as either zebra mussel (gtoreq67% of diet) or macrophyte (gtoreq85% of diet) consumers. Bufflehead, Canvasback, Mallard, and Redhead consumed mainly (gtoreq89%) macrophyte at Fighting Island. Zebra mussel was the principal food of Lesser Scaup (>99%), Greater Scaup (97%), and Bufflehead (72%) in western Lake Erie. Stable isotope analysis revealed enrichment of delta15N in Lesser Scaup (gtoreq2.24%), Greater Scaup (gtoreq1.28%), and Bufflehead (gtoreq0.63%) that exploited mussels relative to conspecifics with macrophyte diets and relative to mussel prey. Representative contaminants of low (hexachlorobenzene (HCB)), moderate (PCB (polychlorinated biphenyl) 153), and high (PCB 180) hydrophobicity were examined in waterfowl. Lipid-normalized concentrations of PCBs 153 and 180 were significantly higher in scaup and Bufflehead that consumed Dreissena than in individuals that ate mainly macrophytes. Among taxa that consumed primarily Dreissena, concentrations of PCBs 153 and 180 were significantly higher in individuals from Lake Erie than in those Fighting Island. Principal components analysis revealed broad differences in contaminant patterns of waterfowl based principally on diet. Results from this study illustrate that Dreissena has become a primary food source of some waterfowl in the lower Great Lakes and serves as an effective conduit for transfer of persistent organic contaminants to higher trophic levels.
Keywords: Nonbreeding Seasons; Contaminants; Trophic Interactions; Bucephala albeola; Bufflehead

Common eider, Somateria mollissima, incubates Gadwall, Anas strepera, eggs: A case of clutch adoption due to human disturbance? - McAlpine, Donald F. (Canadian Field-Naturalist, 1996)
A female Common Eider (Somateria mollissima) was observed on a hatching clutch of Gadwall (Anas strepera) eggs on an island in the Bay of Fundy. This aberrant behaviour may have been related to eider egg predation by gulls, rates of which had been increased by human activity on the island.
Keywords: Behavior; Breeding Season; Common Eider; Somateria mollissima

Spring migration of Spectacled Eiders at Cape Romanzof, Alaska - McCaffery, Brian J.; Wege, Michael L.; Nicolai, Christopher A. (Western Birds, 1999)
Keywords: Somateria fischeri; Spectacled Eider; Nonbreeding Seasons; Migration

Beaver populations and their relation to wetland habitat and breeding waterfowl in Maine - McCall, Thomas C.; Hodgman, Thomas P.; Diefenbach, Duane R.; Owen, Ray B., Jr. (Wetlands, 1996)
The influence of beaver (Castor canadensis) trapping on beaver and waterfowl densities and wetland habitat is not well understood, and this information is needed by managers trying to balance beaver densities and harvest and complaints of nuisance beaver with the abundance of wetlands and waterfowl. During 1988-92 in south-central Maine, we determined the density of beaver colonies and beaver harvest, wetland characteristics, and density of breeding pairs of waterfowl on a 111-k,2 site recently closed to beaver trapping and a similar site open to trapping. Density of beaver colonies increased from 0.15 to 0.32/km-2 (113%) on the untrapped site but changed little (0.19-0.20/km-2) on the trapped site. The number of beaver dams maintained by beaver and the density of beaver colonies were correlated on the untrapped site (r = 0.99, n = 4, P = 0.009) but not on the trapped site (r = -0.18, n = 4, P = 0.820). Number of wetlands was correlated with the density of beaver colonies during 1989-92 on the untrapped site (r = 0.92, n = 4, P = 0.081) but not on the trapped site (r = -0.13, n = 4, P = 0.875). Total surface area of water on the untrapped site increased from 115 to 158 ha (36%); surface area of water remained stable on the trapped area. Species of waterfowl that increased on the untrapped site included Canada geese (Branta canadensis) (4-9/100 km-2), hooded metgansers (Lophodytes cucullatus) (23-29/100 km-2), and mallards (Anas platyrhynchos) (7-12/100 km-2). Numbers of wetlands used by pairs of each species of waterfowl increased on the untrapped site. Overall, a gtoreq 1-year closure of beaver trapping is sufficient to increase the density of beaver colonies, whereas a 2-3 year closure is necessary to increase wetland habitat. More than 3-4 years may be required to begin influencing the density of waterfowl and number of wetlands used by waterfowl.
Keywords: Breeding Season; Habitat; Hooded Merganser; Lophodytes cucullatus

Abundance, distribution, and behavior of common mergansers wintering on a reservoir in southern New Mexico - McCaw, Jack H. Iii; Zwank, Phillip J.; Steiner, Robert L. (Journal of Field Ornithology, 1996)
Arrival dates, mean numbers, departure dates, and proportion of adult males differed for Common Mergansers (Mergus merganser) on Caballo Reservoir between winters of 1992-1993 and 1993-1994. Wintering Common Mergansers spent daylight hours loafing (58.6%), sleeping (17.5%), flying (5.7%), preening (4.0%), stretching (4.0%) and swimming (3.8%). Feeding accounted for lt 4% of daily activity. Diet of Common Mergansers consisted solely of large gizzard shad (Dorosoma cepedianum) during the first winter, but was predominantly threadfin shad (D. potenense) during the second winter. The change in diet was probably a result of most gizzard shad having grown too large to be eaten by Common Merganser by the second winter. Fish caught in gill net samples during both winters were predominately gizzard shad. Other fish netted were: white bass (Morone chrysops), walleye (Stizostedion vitreum), channel catfish (Ictalurus punctatus), and common carp (Cyprinus carpio). We suggest that managers should promote consistent annual recruitment of shad to provide a reliable food source for wintering Common Mergansers.
Keywords: Behavior; Abundance, Distribution, and Trends; Nonbreeding Seasons; Trophic Interactions; Common merganser; Mergus merganser

The response of stonefly (Plecoptera) nymphs to seasonal increases in predation risk - McCutchen, Nicole A. (Canadian Journal of Zoology, 2002)
The main objective of this study was to determine if predation risk accounted for the patterns of stonefly (Plecoptera) nymph abundance in the Maligne Valley watershed, Jasper National Park, Alberta. Seasonal declines in nymph density corresponded to increased use of the Maligne Lake Outlet and Lower Maligne River by harlequin ducks (Histrionicus histrionicus). Neither decline represented a shift from aperiodic to nocturnal use of surface rocks. Rather, rock use remained aperiodic throughout the season despite increases in risk. The decline that occurred in the Maligne Lake Outlet also did not represent a shift from small to large surface rocks. These results, when combined with the results of an odor experiment, suggest that nymphs tend to avoid surface rocks when in the presence of harlequin ducks. Nymph density did not decline seasonally in the Middle Maligne River, a site free of harlequin ducks but inhabited year-round by brook char (Salvelinus fontinalis) and rainbow trout (Onchorhynchus mykiss). Nymphs in this site as well as those exposed to char odor were nocturnally biased in their use of the substrate surface. Overall, predation risk appears to play a strong role in the patterns of stonefly nymph abundance in the Maligne Valley watershed, although not in the way originally expected.
Keywords: Behavior; Breeding Season; Harlequin duck; Histrionicus histrionicus; Trophic Interactions

Harlequin Duck Histrionicus histrionicus distribution and stonefly nymph availability in the Maligne Valley watershed - a preliminary study - McCutchen, N. A.; Ydenberg, R. C. (Wildfowl, 2005)
The relationship between Harlequin Duck Histrionicus histrionicus distribution and stonefly (Plecoptera) nymph availability in the Maligne Valley watershed, Jasper National Park, Canada, was investigated from 1999 to 2000. Invertebrate sampling and duck counts were concentrated in the Maligne Lake Outlet (MLO), Middle Maligne River and Lower Maligne River. Harlequin Ducks were more likely to use the two sites with high nymph availability (MLO and Lower Maligne) than the site with low nymph availability (Middle Maligne). The relationship between Harlequin Duck distribution and other invertebrates was Less consistent. These results suggest that stonefly nymphs play an important role in the distribution of Harlequin Ducks in the Maligne watershed.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Harlequin duck; Histrionicus histrionicus; Trophic Interactions

Nesting of hooded mergansers Lophodytes cucullatus on the Patuxent Wildlife Research Center, Laurel, Maryland - McGilvrey, Frank B. (Auk, 1966)
Keywords: Breeding Season; Hooded Merganser; Lophodytes cucullatus

Underwater hearing in sea ducks with applications for reducing gillnet bycatch through acoustic deterrence - McGrew, K. A.; Crowell, S. E.; Fiely, J. L.; Berlin, A. M.; Olsen, G. H.; James, J.; Hopkins, H.; Williams, C. K. (JOURNAL OF EXPERIMENTAL BIOLOGY, 2022)
As diving foragers, sea ducks are vulnerable to underwater anthropogenic activity, including ships, underwater construction, seismic surveys and gillnet fisheries. Bycatch in gillnets is a contributing source of mortality for sea ducks, killing hundreds of thousands of individuals annually. We researched underwater hearing in sea duck species to increase knowledge of underwater avian acoustic sensitivity and to assist with possible development of gillnet bycatch mitigation strategies that include auditory deterrent devices. We used both psychoacoustic and electrophysiological techniques to investigate underwater duck hearing in several species including the long-tailed duck (Clangula hyemalis), surf scoter (Melanitta perspicillata) and common eider (Somateria mollissima). Psychoacoustic results demonstrated that all species tested share a common range of maximum auditory sensitivity of 1.0-3.0 kHz, with the long-tailed ducks and common eiders at the high end of that range (2.96 kHz), and surf scoters at the low end (1.0 kHz). In addition, our electrophysiological results from 4 surf scoters and 2 long-tailed ducks, while only tested at 0.5, 1 and 2 kHz, generally agree with the audiogram shape from our psychoacoustic testing. The results from this study are applicable to the development of effective acoustic deterrent devices or pingers in the 2-3 kHz range to deter sea ducks from anthropogenic threats.
Times Cited in Web of Science Core Collection: 1 Total Times Cited: 1 Cited Reference Count: 65
Keywords: Long-tailed duck; Surf scoter; Seabird; SEABIRD BYCATCH; POPULATIONS; Anthropogenic; Auditory; BRAIN-STEM-RESPONSES; BY-CATCH; Commoneider; DEVICES; FISHERIES; IN-AIR HEARING; Noise; PHOCOENA-PHOCOENA; PINGERS; pollution; PORPOISE; Psychoacoustics; Sound

Population trends of king and common eiders from spring migration counts at Point Barrow, Alaska between 1994 and 2016 - McGuire, R.; Suydam, R.; Quakenbush, L.; Powell, A. N. (POLAR BIOLOGY, 2019)
Most king (Somateria spectabilis) and common eiders (S. mollissima v-nigra) breeding in the northwestern Nearctic migrate past Point Barrow, Alaska. Spring migration counts have been conducted there since 1953; during 1976-1996, both species declined > 50% for unknown reasons. To evaluate population trends, counts in 2003, 2004, 2015, and 2016 were compared to earlier counts. King eider estimates were 304,966 (95% CI +/- 76,254) in 2003, 591,961 (+/- 172,011) in 2004, 796,419 (+/- 304,011) in 2015, and 322,381 (+/- 145,833) in 2016. Common eider estimates were 114,998 (+/- 28,566) in 2003, 110,561 (+/- 32,087) in 2004, 96,775 (+/- 39,913) in 2015, and 130,390 (+/- 34,548) in 2016. The 2016 estimate was likely biased low for king eiders due to weather (causing large pulses of king eiders to pass within 2 days) and early ice break-up (causing observers to count at greater distances from the flocks). Using all estimates, populations of both species were statistically stable during 1994-2016. Excluding the 2016 count for king eiders indicated a significant increase of 18.63%/year in that population. Photo analysis of flocks in 2016 indicated that observer counts averaged 4% lower, species detection was not different, but females' counts were underestimated by 25%. Methods should be refined to reduce bias and variability. Ice-based spring counts are becoming more difficult due to earlier break-up, less stable ice, and new techniques or locations; or a switch to land-based summer/fall migration counts are needed. Population monitoring is needed to ensure sustainability of harvests for these valuable subsistence resources.
Times Cited in Web of Science Core Collection: 1 Total Times Cited: 1 Cited Reference Count: 62
Keywords: Somateria mollissima; Somateria spectabilis; Arctic; SOMATERIA-MOLLISSIMA; VARIABILITY; BREEDING SUCCESS; DISTANCE; HETEROGENEITY; PREY; VISIBILITY BIAS; Beaufort sea; Chukchi sea; DECLINE; INCREASES; Population estimate; SPECTABILIS

A Highly Repeated Retropseudogene-Like Sequence in DNA of the Red-Breasted Merganser Mergus-Serrator - McHugh, K. P.; Madsen, C. S.; De Kloet, S. R. (Gene (Amsterdam), 1990)
Two highly repeated nucleotide sequences (RBMI and RBMII) cloned from an EcoRI digest of DNA of the redbreasted merganser (Mergus serrator) account for approx. 5 to 10% of the DNA of M. serrator and the closely related Mergus merganser. Complete DNA digestion of seven members of the Mergini with EcoRI produces distinct, relatively species-specific patterns of a few high-Mr (> 1.5 kb) fragments of RBMI-like material. In such digests RBMII forms ladder-type patterns with monomers of approx. 200 bp. The sequence of a cloned 2.6-kg RBMI fragment from M. serrator contains several extended (up to 70 bp) and modified poly(dA) sequences, two open reading frames in opposite orientation to the longest poly(dA) sequence and two direct 10-bp repeats suggesting that RBMI is a rearranged retropseudogene-like element.
Keywords: Techniques; Mergus serrator; Red-breasted merganser

Effect of Nonpetroleum Oil Spills on Wintering Birds near Vancouver British-Columbia Canada - McKelvey, R. W.; Robertson, I.; Whitehead, P. E. (Marine Pollution Bulletin, 1980)
Spills of vegetable oils at Vancouver habor have caused greater losses of birds than spills of petroleum oils. Vegetable oils affect birds by feather wetting but do not exhibit odor and slick characteristics of petroleum oils. Because most vegetable oils are edible their potential danger to aquatic birds may go unnoticed; sites of storage and transhipment of vegetable oils may be overlooked in oil spill contigency planning. The birds studied included Western grebe (Podiceps occidentalis), gull (Larus glaucescens), Barrow's goldeneye (Bucephala islandica), surf scoter (Melanitta perspicillata) and scaup (Aythya spp.).
Keywords: Nonbreeding Seasons; Melanitta perspicillata; Surf Scoter; Contaminants; Barrow's Goldeneye; Bucephala islandica

A new model to estimate daily energy expenditure for wintering waterfowl - McKinney, Richard A.; McWilliams, Scott R. (Wilson Bulletin, 2005)
Current models to estimate daily energy expenditure (DEE) for free-living birds are limited to either those that use fixed thermoregulatory costs or those that more accurately estimate thermoregulatory costs, but require extensive and often logistically difficult measurements. Here, we propose a model based on basal metabolic rate (BMR), activity budgets, and site-specific energetic costs of thermoregulation that requires only simple measures of ambient temperature and wind speed to provide estimates of DEE. We use the model to calculate the DEE of Buffleheads (Bucephola albeola) wintering at six habitats that afford differing degrees of protection from exposure within Narragansett Bay, Rhode Island. Bufflehead activity budget data collected during the winters of 2001-2002 and 2002-2003, along with average temperatures and wind speeds at the sites, were used to calculate DEE that ranged from 46.9 to 52.4 kJ/hr and increased with increasing wind speed. The energetic cost of thermoregulation composed as much as 28% of total DEE and increased with wind speed. Our DEE values were 13.4% higher, and thermoregulatory costs were up to 2x higher than those calculated using an existing model that incorporates fixed thermoregulatory costs. We also saw an increase in feeding activity with increasing wind speed; sensitivity analysis of the effects of wind speed and feeding activity showed that a 1 m/sec increase in wind speed at our sites increased DEE by 2.5%, whereas a corresponding increase in feeding activity increased DEE by 4.5%. This suggests that in temperate winter habitats, increased feeding activity may have a greater impact on Bufflehead DEE than wind exposure. Site-specific model estimates of DEE could also provide additional insight into the relative contribution of environmental conditions and changes in waterfowl behavior to DEE.
Keywords: Behavior; Nonbreeding Seasons; Energetics and Nutrition; Bucephala albeola; Bufflehead

Habitat characteristics associated with the distribution and abundance of Histrionicus histrionicus (Harlequin Ducks) wintering in southern New England - McKinney, Richard A.; McWilliams, Scott R.; Charpentier, Michael A. (Northeastern Naturalist, 2007)
Histrionicus histrionicus (Harlequin Ducks) that winter along the east coast of North America are listed as a Population of special concern in Canada, and they use several coastal wintering sites in southern New England that are subject to varying degrees of urbanization. We studied patterns of habitat use by Harlequin Ducks at 12 known wintering sites in southern New England. An average of 327 +/- 114 Harlequin Ducks were found at the sites during the winters of 2001-2003. More Harlequin Ducks wintered at sites south of Cape Cod, MA that had greater mol tusk (709,133 +/- 504,568 versus 97, 154 +/- 72.427 kcal ha(-1)) and crustacean (27,907 +/- 16,312 versus 1412 +/- 1675 kcal ha(-1)) prey energy density, and a higher index of hunting activity (2.4 +/- 1.2 versus 1.4 +/- 0.5) than sites to the north. We used logistic regression analysis at 12 sites inhabited by Harlequin Ducks and 12 nearby sites of similar geomorphology that did not Support Harlequin Ducks to identify habitat characteristics that best explained their distribution in southern New England. Our analysis identified two habitat characteristics that affected the likelihood a site was used by Harlequin Ducks: 1) the proportion of residential, commercial, and industrial land use within a 100-m radius of the perimeter of the site; and 2) distance to the nearest Harlequin Duck wintering site. However, other factors. including those related to their extremely low population size, need to also be considered as recommendations are developed for the conservation of east coast Harlequin Ducks.
Keywords: Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Habitat

Status and Distribution of Wintering Waterfowl in Narragansett Bay, Rhode Island, 2005-2014 - McKinney, R. A.; Raposa, K. B.; Trocki, C. L. (Northeastern Naturalist, 2015)
Surveys of wintering waterfowl can aid in both identifying estuarine habitats currently being used by species of conservation concern so that the sites can be targeted for protection and restoration, and in providing a baseline assessment from which the effects of future changes in wintering habitat can be assessed. In an effort to better understand the local distribution of wintering waterfowl during the period 2005-2014, we undertook a study of waterfowl abundance and distribution in Narragansett Bay, RI, a moderate-sized estuary located in the northeastern US within the Atlantic Flyway. Overall waterfowl abundance in the Bay ranged from 15,002 individuals in 2006 to 26,163 individuals in 2010 and averaged 20,062 +/- 3393 individuals over the 10-y period. Species richness ranged from 1.80 to 10.8 per site; most of the sites with high species richness were located in the Upper Bay. Based on our counts from 67 ground locations, the Narragansett Bay waterfowl community was dominated by Aythya affinis (Lesser Scaup) and A. marila (Greater Scaup), Branta bernicla (Brant), and Branta canadensis (Canada Geese) over the survey period. Waterfowl-community composition indicated that the Upper Bay, an environment characterized by low wave-energy, shallow coves, sheltered embayments, and salt marshes, supported mostly dabbling ducks, geese, and swans. The Lower Bay, an environment characterized by higher wave-energy, rocky shorelines, and deeper open-water habitats, supported mostly sea ducks and other diving-duck species. Abundance over the survey period was relatively stable, and observed patterns of waterfowl distribution suggest that conservation actions to maintain shallow-water habitats, including efforts to protect and restore salt marsh habitat, will help to maintain resources needed by many of the waterfowl species wintering in the Bay.
McKinney, Richard A. Raposa, Kenneth B. Trocki, Carol L.
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; Mergus merganser; Mergus serrator; Bucephala albeola; Bufflehead; Black Scoter; Hooded Merganser; Lophodytes cucullatus; Bucephala islandica; Abundance, Distribution, & Trends; Nonbreeding season; Barrow’s Goldeneye; Common Merganser; Melanitta americana; Red-breasted Merganser; Harlequin Duck

Genetic evidence for kin-based female social structure in common eiders (Somateria mollissima) - McKinnon, Laura; Gilchrist, H. Grant; Scribner, Kim T. (Behavioral Ecology, 2006)
Kin-based social groups are commonly studied among cooperatively breeding species but have been less studied in "nontraditional" group breeding systems. We investigated the presence of kin-based sociality among females in the common eider (Somateria mollisima), a colonial nesting sea duck that exhibits high levels of natal philopatry in females. Previous studies of female sociality in common eiders have been restricted to observations during brood rearing. However, aggregations of female common ciders are also observed during other periods of the life cycle such as colony arrival and nesting. Here we apply a novel, empirical framework using molecular markers and field sampling to genetically characterize female social groups at several stages of the common eider life cycle. When compared with mean estimates of interindividual relatedness for the entire colony, significantly higher levels of relatedness were found between females within groups arriving to the colony in flight, between females and nearest neighbors at the time of nest site selection, and between groups of females departing the colony with ducklings. Both full-sibling and half-sibling equivalent relationships were also found within these groups. Therefore, throughout each of several stages including in-flight colony arrival, nesting, and brood rearing, we provide the first genetically confirmed evidence of female kin-based social groups in common ciders and anseriformes in general.
Keywords: Behavior; Breeding Season; Common Eider; Somateria mollissima

The spring behavior of wild Steller Eiders - McKnney, F. (Condor, 1965)
The behavior of Polysticta stelleri (Anatidae) was studied during April and May at 2 wintering areas on the Alaska Peninsula. The birds were highly social when feeding and resting, often massing in tightly packed rafts. When diving for food, the members of a flock submerged almost simultaneously. In courting parties, males performed several distinct displays and frequently made pre-flight movements and Short Flights. In contrast to courting parties of Somateria mollissima, which often dive, those of Polysticta often took to the air. Pairs made deliberate fights away from the flock to copulate. After copulation, the pair often returned immediately to the flock. Pre-copulatory displays are less conspicuous than those of Somateria. Strong tendencies to flock densely and to fly readily probably have survival value against aerial predators, and these tendencies appear to have affected feeding, pairing, and copulatory behavior. Some differences between the displays of Polysticta and Somateria are thought to have resulted from selection pressure tending to reduce conspicuousness in the former species. ABSTRACT AUTHORS: Author
Keywords: Behavior; Nonbreeding Seasons; Polysticta stelleri; Steller's eider

Effects of Snow and Ice on Waterfowl Distribution in the Central Canadian Arctic Islands - McLaren, M. A.; Alliston, W. G. (Arctic, 1985)
Aerial surveys were conducted in 1974 and 1975 to determine distribution and abundance of waterfowl along the coasts of Somerset, Cornwallis, Little Cornwallis,and Byam Martin islands, Boothia Peninsula, and parts of Prince of Wales. Devon,Bathurst, and Melville islands. Waterfowl nested normally in 1975 but were prevented from doing so in 1974 by a late thaw. In 1974 Barrow Strait was ice free by 1 June. Densities of most species were lowest in spring 1975 than in 1974, when inhospitable conditions inland forced the birds to concentrate in coastal areas. In late summer brant (Branta bernicla) and oldsquaw (Clangula hyemalis) numbers were > in 1975 than in 1974; Brant left the central high Arctic in midsummer 1974, but the reason for the smaller numbers of Oldsquaw is not evident. Both snow geese (Chen caerulescens) and eiders (Somateria spp.) were more abundant in late summer 1974 than in 1975. Many snow geese moved to southeastern Somerset Island and adjacent waters to molt in 1974. In 1975 many eiders and snow geese remained at inland locations with their broods. Queens Channel, northern Somerset Island and Bellot Strait were important to waterfowl irrespective of spring phenology. Melville and Byam Martin islands were used by brant, and Canada geese (B. canadensis) occurred mainly on the Boothia Peninsula. Snow geese were abundant in both years in southeastern Somerset Island, particularly near Creswell Bay, where both breeding and molting occurred. Coastal waters of Barrow Strait, Prince Regent Inlet and the Gulf of Boothia were heavily used by oldsquaw in spring and summer, and Crooked Lake, Prince of Wales Island, was used by many molting oldsquaw in both years. Common eiders (S. mollisima) occurred principally in Queens Channel, Barrow Strait and near Bellot Strait; king eiders (S. spectabilis) concentrated in the same areas but were more widely distributed throughout the study area.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons; Habitat

Waterfowl Populations in Eastern Lancaster Sound and Western Baffin Bay Canada - McLaren, P. L.; McLaren, M. A. (Arctic, 1982)
The seasonal distributions of oldsquaws (Clangula hyemalis), common eiders (Somateria mollissima) and king eiders (S. spectabilis) were determined through aerial surveys in eastern Lancaster Sound (1976, 1978 and 1979) and northwestern Baffin Bay (1978 and 1979). Sightings of geese are summarized. The major spring influx of both eiders occurs about the 2nd wk of May but most oldsquaws do not arrive until the 1st half of June. In spring, all 3 species are rare in offshore areas, are most abundant along coasts in the northern half of the study area and tend to depart to nesting areas during the last week of June. Oldsquaws molt along coasts of Lancaster Sound and northwestern Baffin Bay, but both species of eiders undertake molt migrations. Three waves of eider out-migration were detected in 1976 and 1978. Distribution and movements within the study area are related to probable migration routes and ice conditions.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Common Eider; Nonbreeding Seasons; Molt; Clangula hyemalis; Long-tailed Duck; Migration; Somateria mollissima; King Eider; Somateria spectabilis

Further Data on Interspecific Competition at a Joint Bufflehead Goldeneye Nest Site - McLaren, W. D. (Canadian Field-Naturalist, 1969)
Keywords: Behavior; Breeding Season; Bucephala albeola; Bufflehead

Common Eider Somateria-Mollissima Plays Possum - McNair, D. B. (Wilson Bulletin, 1981)
Keywords: Behavior; Common Eider; Somateria mollissima

Monitoring nest box use by cavity-nesting ducks on acid-stressed lakes in Ontario, Canada - McNicol, Donald K.; Walton, Russel A.; Mallory, Mark L. (Wildlife Biology, 1997)
Nest boxes erected on 75 small lakes near Sudbury, Canada were monitored annually between 1987 and 1996 to measure the response of cavity-nesting waterfowl to changing chemical and biological conditions of their nesting habitat from the effects of acidification. Nest boxes were used mainly by common goldeneyes Bucephala clangula and hooded mergansers Lophodytes cucullatus, although a few were occupied by common mergansers Mergus merganser and wood ducks Aix sponsa. Use by hooded mergansers and wood ducks increased from 1987 to 1996, while use by goldeneyes remained stable. Patterns in nest box use reflected general population trends observed in the area. Interspecific nest parasitism also increased to 33% of all nests in 1996, probably a consequence of more hooded merganser nests. Clutch size, nesting and hatching success of goldeneye and hooded merganser eggs were similar to values reported for conspecifics in other studies. Overall, interspecific nest parasitism did not appear to affect the nesting success of either species. Although goldeneyes nested more often on fishless lakes early in the study, overall, fish presence, pH-value, lake area and connectivity were not related to nesting attempts or measures of nesting success for either species. Therefore, it is believed that for common goldeneyes and hooded mergansers currently breeding in the acid-stressed Sudbury area, habitat characteristics have little influence on nest site selection, particularly when compared to their documented effects on brood-rearing. However, monitoring of nest boxes may prove a less expensive method than aerial surveys to track population responses of cavity-nesting species to chemical improvements.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Bucephala clangula; Common Goldeneye; Contaminants; Habitat; Hooded Merganser; Lophodytes cucullatus

Lead isotopic signatures in blood from incubating common eiders (Somateria mollissima) in the central Baltic Sea - McPartland, M.; Garbus, S. E.; Lierhagen, S.; Sonne, C.; Krokje, A. (ENVIRONMENT INTERNATIONAL, 2020)
The Christianso colony of common eiders (Somateria mollissima) in the central Baltic Sea were exposed to high levels of Pb during the 2018 breeding season that were not present in 2017. Due to these high Pb blood levels, the present study investigated possible Pb sources and Pb dynamics within this vulnerable colony. We analyzed body mass and lead isotopic ratios (Pb-IRs) in blood taken from the same incubating eiders at the early (day 4) and late (day 24) stages of incubation during the 2018 breeding season (n = 23). Pb-IRs 208/207, 208/206, 206/207, and 207/206 were analyzed using high resolution inductively coupled mass spectrometry. We found largely similar Pb-IRs from the different stages of incubation indicating a predominantly constant endogenous source of Pb exposure. We suggest the increasing Pb levels come from pre-nesting and nesting foraging and from medullary bone release. The similar Pb-IRs also indicate continued metabolization of the medullary bone to meet the nutritional and energy demands of incubation. Comparisons to Pb-IR reports from the Baltic Sea showed multiple sources of pollution distinguished by a difference between Pb-IRs in individuals with Pb blood concentrations> 500 mu g/kg ww and< 500 mu g/kg ww. The most highly contaminated individuals in the present study had Pb-IRs similar to those of Pb ammunition indicating shot pellet uptake. This study further emphasizes the need for continued biomonitoring of the Christianso colony, including fecal sampling and environmental field sampling to identify the origin and extent of dietary Pb exposure on Christianso. As a representative unit of the Baltic Flyway population; the Christianso colony provides an important opportunity for continued investigation into Pb contamination, population dynamics, and declines.
Times Cited in Web of Science Core Collection: 5 Total Times Cited: 5 Cited Reference Count: 82
Keywords: ACCUMULATION; Biomonitoring; TRACE-ELEMENTS; BODY CONDITION; EXPOSURE; REPRODUCTION; SELENIUM; Baltic Sea; MORTALITY EVENT; Avian; RATIOS; AMMUNITION; BIOCHEMISTRY; HR-ICP-MS; Isotope; Lead poisoning

Circulating trace elements: Comparison between early and late incubation in common eiders (Somateria mollissima) in the central Baltic Sea - McPartland, M.; Noori, B.; Garbus, S. E.; Lierhagen, S.; Sonne, C.; Krokje, A. (ENVIRONMENTAL RESEARCH, 2020)
We analyzed body mass and a panel of 64 trace elements in blood from incubating common eiders (Somateria mollissima) in the central Baltic Sea during the breeding seasons of 2017 (n = 27) and 2018 (n = 23). Using a noninvasive approach, the same incubating eiders nesting on Christiansu, Denmark were sampled once on day 4 and day 24 of incubation to provide a comparison between the early and late stages of incubation. Blood concentrations of chemical elements were quantified using high-resolution inductively coupled plasma mass spectrometry (HR-ICP-MS). Cadmium and lead significantly increased over the course of the incubation period while body mass, barium, calcium, cerium, cesium, iron, magnesium, manganese, molybdenum, phosphorus, selenium, strontium, sulfur, uranium, and zinc all significantly decreased. Excluding lead, all trace elements were within expected ranges. Lead blood concentrations had a 4.7-fold increase from 2017 to 2018 indicating a potential health threat. However, internal interactions between trace elements must be considered when making comparisons to toxicological thresholds. Body mass and many essential elements showed significantly higher levels in 2017 than 2018, which could be an indication of limitations in preferred food availability or harsher fasting conditions. Additional sampling years are needed to further investigate if these results reflect yearly fluctuations or decreasing health within the Christiansu eider colony. There was little overlap in element blood concentrations and body mass between days of incubation, indicating these parameters are affected by the physiological processes of reproduction and incubation. We recommend continued biomonitoring and use of complete trace element analysis for the Christiansu eiders to further understand year-to-year variations within colonies. Further investigation into the spatial ecology of the colony is also needed to provide a more robust understanding of exposure and source identification of trace elements.
Times Cited in Web of Science Core Collection: 0 Total Times Cited: 0 Cited Reference Count: 74
Keywords: PERSISTENT ORGANIC POLLUTANTS; MERCURY; Biomonitoring; BODY CONDITION; Multiple stressors; CONTAMINANTS; REPRODUCTION; Heavy metals; CLINICAL-CHEMICAL PARAMETERS; MORTALITY EVENT; Avian; BLOOD; HR-ICP-MS; COST; Essential elements; SEABIRD

The Development and Pathogenesis of Eustrongylides-Tubifex Nematoda Dioctophymatoidea in Piscivorous Birds - Measures, L. N. (Canadian Journal of Zoology, 1988)
Experimental infections of laboratory-raised birds supported field data indicating that Common Mergansers (Mergus merganser L.) (prevalence = 20.8%, mean intensity = 3.2) and Red-breasted Mergansers (Mergus serrator L.) (prevalence = 4.0%, mean intensity = 1) are important hosts of Eustrongylides tubifex in Ontario. Fourth-stage larvae from naturally infected fish were used to infect birds. In birds, the fourth moult occurred 2 days postinfection and adult worms retained the fourth-stage cuticle. In experimentally infected mergansers, E. tubifex developed in the tunica muscularis of the proventriculus, eliciting raised, oval tumors. Worms matured rapidly, produced eggs 10 to 17 days postinfection, and then degenerated. Tumors resolved rapidly in the proventriculus which returned to its normal condition by approximately 30 days postinfection. Worms were sometimes found in aberrant locations such as the gizzard and liver but this occurred less frequently in Common Mergansers and Red-breasted Mergansers than in other experimentally infected birds (Hooded Mergansers (Mergus cucullatus L.), Great Blue Heron (Ardea herodias L.), Double-crested Cormorants (Phalacrocorax auritus (Lesson)), and domestic ducks (Anas platyrhynchos L.)).
Keywords: Common merganser; Mergus merganser; Mergus serrator; Red-breasted merganser; Hooded Merganser; Lophodytes cucullatus; Parasites

Epizootiology Pathology and Description of Eustrongylides-Tubifex Nematoda Dioctophymatoidea in Fish - Measures, L. N. (Canadian Journal of Zoology, 1988)
In Guelph Lake, a man-made reservoir in Ontario, Canada, prevalence of larval Eustrongylides tubifex in pumpkinseed (Lepomis gibbosus), rock bass (Ambloplites rupestris), and yellow perch (Perca flavescens) was 12.9% and mean intensity ranged from 1 to 1.8. Larvae were encapsulated on the mesentery of fish. Pumpkinseed and yellow perch were the important fish hosts in Guelph Lake as most larvae in these fish were alive. In contrast, 40% of larvae in rock bass were dead and calcified. Third- and fourth-stage larvae from naturally infected fish are described. Larvae in the three species of fish elicited a granulomatous inflammatory reaction. Attempts to transfer third-stage larvae from experimentally infected oligochaetes and third-stage larvae from naturally infected fish to laboratory-reared pumpkinseed were unsuccessful. Fourth-stage larvae from naturally infected fish were transferred successfully to pumpkinseed. Eutropic lakes such as Guelph Lake are particularly suitable enzootic areas because of the abundant populations of tubificid intermediate hosts and the presence of fish hosts such as pumpkinseed and perch. The advanced stage and development of larvae (to the fourth stage) in fish likely represents an adaptation for a parasite that occurs in a migratory host such as Common Mergansers (Mergus merganser), which frequent Guelph Lake for only about 1 month in spring and fall.
Keywords: Nonbreeding Seasons; Common merganser; Mergus merganser; Parasites

Revision of the Genus Eustrongylides Jagerskiold 1909 Nematoda Dioctopymatoidea of Piscivorous Birds - Measures, L. N. (Canadian Journal of Zoology, 1988)
The genus Eustrongylides Jagerskiold, 1909 (Namatoda: Dioctophymatoidea) is revised based on examination of adult E. tubifex from experimentally infected Common Mergansers (Mergus merganser) and specimens of Eustrongylides spp. from various museums. Only three species are considered distinguishable: E. tubifex (Nitzsch in Rudolphi, 1819) Jagerskiold, 1909 (the type species), E. ignotus Jagerskiold, 1909, and E. excisus Jagerskiold, 1909. All three species are redescribed. Eustrongylides perpapillatus Jagerskiold, 1909 is regarded as a synonym of E. tubifex. Eustrongylides formosensis Sugimoto, 1933, E. indicus Ali, 1971, E. phalacrocoracis Johnston and Mawson, 1941, E. plotinus Johnston and Mawson, 1941, E. tricolor Sugimoto, 1931, and E. excisus amoyensis Hoeppli, Hsu, and Wu, 1929 are regarded as synonyms of E. excisus. Nine additional species are considered species inquirendae; [Eustrongylides spinispiculum, E. wenrichi, E. gadepsis, E. acrochordi, E. sinicus, E. rubrum, E. papillosus, E. mergorum and E. africanus].
Keywords: Common merganser; Mergus merganser; Parasites

Annual cycle of White-winged Scoters (Melanitta fusca) in eastern North America: migratory phenology, population delineation, and connectivity - Meattey, D. E.; McWilliams, S. R.; Paton, P. W. C.; Lepage, C.; Gilliland, S. G.; Savoy, L.; Olsen, G. H.; Osenkowski, J. E. (CANADIAN JOURNAL OF ZOOLOGY, 2018)
Understanding full annual cycle movements of long-distance migrants is essential for delineating populations, assessing connectivity, evaluating crossover effects between life stages, and informing management strategies for vulnerable or declining species. We used implanted satellite transmitters to track up to 2 years of annual cycle movements of 52 adult female White-winged Scoters (Melanitta fusca (Linnaeus, 1758)) captured in the eastern United States and Canada. We used these data to document annual cycle phenology; delineate migration routes; identify primary areas used during winter, stopover, breeding, and molt; and assess the strength of migratory connectivity and spatial population structure. Most White-winged Scoters wintered along the Atlantic coast from Nova Scotia to southern New England, with some on Lake Ontario. White-winged Scoters followed four migration routes to breeding areas from Quebec to the Northwest Territories. Principal postbreeding molting areas were in James Bay and the St. Lawrence River estuary. Migration phenology was synchronous regardless of winter or breeding origin. Cluster analyses delineated two primary breeding areas: one molting area and one wintering area. White-winged Scoters demonstrated overall weak to moderate connectivity among life stages, with molting to wintering connectivity the strongest. Thus, White-winged Scoters that winter in eastern North America appear to constitute a single continuous population.
Times Cited in Web of Science Core Collection: 11 Total Times Cited: 11 Cited Reference Count: 90
Keywords: migratory connectivity; Melanitta fusca; White-winged Scoter; DUCKS; SELECTION; KING EIDERS; MOVEMENTS; SITE FIDELITY; satellite telemetry; HABITAT USE; population delineation; SURF SCOTERS; annual cycle; phenology; REMIGIAL MOLT; PACIFIC COAST; MOLT MIGRATION

Resource selection and wintering phenology of White-winged Scoters in southern New England: Implications for offshore wind energy development - Meattey, D. E.; McWilliams, S. R.; Paton, P. W. C.; Lepage, C.; Gilliland, S. G.; Savoy, L.; Olsen, G. H.; Osenkowski, J. E. (CONDOR, 2019)
Southern New England provides key wintering habitat for White-winged Scoters (Melanitta fusca). This area has also pioneered the development of offshore wind energy in North America. The U.S. Bureau of Ocean Energy Management (BOEM) has established 9 Wind Energy Area (WEA) lease blocks along the Atlantic Outer Continental Shelf in areas that may provide important staging and wintering habitat for scoters and other species of sea ducks. Concern over the potential impact of offshore wind energy on sea duck populations has led to efforts to develop models to understand their distribution, habitat use, and site fidelity. We used satellite telemetry to document winter phenology and site fidelity, as well as fine-scale resource selection and habitat use, of 40 White-winged Scoters along the southern New England continental shelf. Scoters spent over half of the annual cycle on the wintering grounds and demonstrated a high degree of interannual site fidelity to composite core-use areas. Sizes of individual 50% core-use home ranges were variable (X = 868 km(2); range: 32-4,220 km(2)) and individual 95% utilization distributions ranged widely (X = 4,388 km(2); range: 272-18,235 km(2)). More than half of all tagged birds occupied 2 or more discrete core-use areas that were up to 400 km apart. Throughout the study area, scoters selected areas with lower salinity, lower sea surface temperature, higher chlorophyll-a concentrations, and higher hard-bottom substrate probability. Resource selection function models classified 18,649 km(2) (23%) of the study area as high probability of use, which included or immediately bordered similar to 420 km(2) of proposed WEA lease blocks. Future offshore wind energy developments in the region should avoid key habitats highlighted by this study and carefully consider the environmental characteristics selected by sea ducks when planning and siting future WEAs.
Times Cited in Web of Science Core Collection: 9 Total Times Cited: 10 Cited Reference Count: 108
Keywords: habitat use; Melanitta fusca; White-winged Scoter; COMMON EIDERS; EIDERS SOMATERIA-MOLLISSIMA; KING EIDERS; SITE FIDELITY; COLLISION RISK; satellite telemetry; SEA DUCKS; resource selection function; SURF SCOTERS; phenology; SPECTACLED EIDERS; BLACK SCOTERS; offshore wind energy; New England

Elevated mercury levels in a wintering population of common eiders (Somateria mollissima) in the northeastern United States - Meattey, D. E.; Savoy, L.; Beuth, J.; Pau, N.; O'Brien, K.; Osenkowski, J.; Regan, K.; Lasorsa, B.; Johnson, I. (Marine Pollution Bulletin, 2014)
In North America and Europe, sea ducks are important indicators of ecological health and inshore marine pollution. To explore spatial variation in mercury accumulation in common eiders in the northeastern United States, we compared concentrations of total mercury in common eider blood at several New England locations between 1998 and 2013. Eider food items (mollusks) were collected and analyzed to determine if mercury concentrations in eider blood were indicative of local mercury bioavailability. Eiders from Plum Island Sound, MA had a significantly higher mean blood mercury concentration (0.83 mu g/g) than those in other locations. Mean mercury levels in this population were also nearly three times higher than any blood mercury concentrations reported for common eiders in published literature. We observed consistent patterns in eider blood mercury and blue mussel mercury concentrations between sites, suggesting a tentative predictive quality between the two species. (C) 2014 Elsevier Ltd. All rights reserved.
Meattey, Dustin E. Savoy, Lucas Beuth, Josh Pau, Nancy O'Brien, Kathleen Osenkowski, Jason Regan, Kevin Lasorsa, Brenda Johnson, Ian
Keywords: Common Eider; Contaminants; Somateria mollissima

Ringing Studies of Goosanders in Northumberland - Meek, E. R.; Little, B. (British Birds, 1977)
Keywords: Common merganser; Mergus merganser

The Spread of the Goosander in Britain and Ireland - Meek, E. R.; Little, B. (British Birds, 1977)
Keywords: Abundance, Distribution, and Trends; Common merganser; Mergus merganser

EFFECTS OF PREDATION BY BIRDS ON GOOSENECK BARNACLE POLLICIPES-POLYMERUS SOWERBY DISTRIBUTION AND ABUNDANCE - Meese, R. J. (Journal of Experimental Marine Biology and Ecology, 1993)
MEESE, RJ

King eider (Somateria spectabilis) brood ecology: Correlates of duckling survival - Mehl, Katherine R.; Alisauskas, Ray T. (Auk, 2007)
Events during duckling growth can influence waterfowl population dynamics. To gain insight into King Eider (Somateria spectabilis) brood ecology, we monitored 111 and 46 individually marked ducklings from broods of 23 and 11 radiomarked King Eiders during 2000 and 2001, respectively. We used capture-mark-resight data to model apparent survival of King Eider ducklings and broods, and multistratum analysis to estimate probabilities of (1) movement among habitats and (2) apparent survival of ducklings that used various habitats. In addition, we recorded length of stay for 7 and 18 radiomarked females with failed nesting attempts during 2000 and 2001, respectively. Complete loss of individual broods accounted for 84% of all duckling mortality (106 of 126 mortalities), with most brood loss (74%; 17 of 23 broods lost) within the first two days after hatch. Estimated apparent survival of ducklings to 24 days of age was 0.10 (95% CI: 0.05 to 0.15). Apparent survival of broods was estimated to be 0.31 (95% CI: 0.13 to 0.50). Our data suggested an interaction between female size and hatch date, whereby larger females whose ducklings also hatched earlier raised more ducklings than either small females or those with ducklings that hatched later. Overland brood movements >= 1 km occurred in both years, and survival was greatest for ducklings on smaller ponds away from the central nesting area at Karrak Lake, Nunavut. Females that experienced nest failure and total brood loss left the study area earlier than females with surviving ducklings.
Keywords: Breeding Season; King Eider; Somateria spectabilis; Dispersal; Survival

To winter East or West? Heterogeneity in winter philopatry in a central-Arctic population of King Eiders - Mehl, Katherine R.; Alisauskas, Ray T.; Hobson, Keith A.; Kellett, Dana K. (Condor, 2004)
We used banding data from King Eiders (Somateria spectabilis) at Karrak Lake, Nunavut, Canada, during 2001 and 2002 in conjunction with analysis of naturally occurring stable isotopes (13C, 15N) from feathers to connect winter and breeding areas of individuals. We also investigated the occurrence of winter philopatry among nesting females, and examined cross-seasonal effects of wintering area on subsequent breeding. Isotopic data suggested that 66-73% of this central-arctic breeding population wintered to the west (i.e., Bering Sea and North Pacific) and the remaining 24-37% wintered to the east (i.e., west Greenland, northwest Atlantic). In contrast, limited band recoveries from hunter-killed King Eiders marked at the same breeding location suggested that about 56% of individuals were shot in eastern wintering areas. These differences likely reflect stronger hunting pressures along the coast of Greenland, which result in more band recoveries for this area. Our results suggest that female King Eiders were not strongly philopatric to wintering areas among years. Individuals that wintered in western seas initiated nests 1.9 days earlier and had slightly larger clutches during early initiation relative to females that wintered in the east. Nest parasitism appeared to be biased toward earlier nesters, many of which wintered in the west. Female condition during incubation did not vary by wintering area. Our results have important implications for gene flow and for potentially associating wintering-area conditions with overall demography and individual fitness of King Eiders.
Keywords: Breeding Season; Nonbreeding Seasons; Productivity; King Eider; Somateria spectabilis; Dispersal; Population Delineation

Linking breeding and wintering areas of king eiders: Making use of polar isotopic gradients - Mehl, Katherine R.; Alisauskas, Ray T.; Hobson, Keith A.; Merkel, Flemming R. (Journal of Wildlife Management, 2005)
Keywords: Breeding Season; Nonbreeding Seasons; King Eider; Somateria spectabilis; Techniques; Population Delineation

Breeding Population Size of the Common Eider Somateria-Mollissima in Kongsfjorden Svalbard Arctic Ocean 1981-1987 - Mehlum, F. (Norsk Polarinstitutt Skrifter, 1991)
The breeding population size of the Common Eider Somateria mollissima was censused during a seven year period (1981-1987) in Kongsfjorden, Svalbard. The total number of breeding pairs fluctuated between 1,000 and 3,400 depending on the sea-ice conditions in the fjord. In seasons with late breakup of sea-ice in the fjord (1981 and 1986), fewer Eiders occupied their breeding islands than in seasons with early breakup. The proportion of breeding pairs on each island also varied with the years. In years with early ice breakup and snow-melt the major part of the Eiders nested at relatively low density on the largest island in the area. In years with late breakup and snow melt, most of the breeding birds inhabited the smaller and outermost islands. Egg clutch sizes varied with egg-laying dates, with the smallest clutches late in the season.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Common Eider; Somateria mollissima

Egg Predation in a Breeding Colony of the Common Eider Somateria-Mollissima in Kongsfjorden Svalbard Arctic Ocean - Mehlum, F. (Norsk Polarinstitutt Skrifter, 1991)
Egg predation was studied in a colony of Common Eiders Somateria mollissima in Svalbard during three breeding seasons, 1982-1984. The colony was located on the small island Mietheholmen (3700 m2) and was inacessible to the Arctic Fox Alopex lagopus after the late spring breakup of the surrounding sea-ice. Egg-laying started after the island was free of ice. The main predators on Eider egg was the Glaucous Gull Larus Hyperboreus. Based on mean daily egg predation rates during different parts of the breeding period, an estimate of the total egg loss was made. A total of 41.5, 77.9 and 77.9% of all eggs laid were subject to predation or in other ways lost during the 25-day incubation period in the three breeding seasons 1982-1984 respectively. The lowest predation rate was registered in the most densely populated parts of the colony. All predation observed occurred while the female was away from the nest for short rest bouts on the sea.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Productivity; Trophic Interactions

Effects of sea ice on breeding numbers and clutch size of a high arctic population of the common eider Somateria mollissima - Mehlum, F. (Polar Science, 2012)
Times Cited: 2 Mehlum, Fridtjof 2 SI
Keywords: Breeding Season; Productivity; Common eider; somateria mollissima

Effect of Down Harvesting on Nesting Success in a Colony of the Common Eider Somateria-Mollissima in Svalbard Arctic Ocean - Mehlum, F.; Neilsen, L.; Gjertz, I. (Norsk Polarinstitutt Skrifter, 1991)
The effect of down harvesting in a high arctic colony of breeding Eiders Somateria mollissima was studied in Svalbard in 1987. An experiment was conducted with three groups of harvested nests and one control group of unharvested nests. The nests were harvested in the first half, or in both halves of the incubation period. A total of 716 nests were included in the experiment. No difference in nest success of egg loss was recorded between harvested and unharvested nests.
Keywords: Conservation; Breeding Season; Common Eider; Somateria mollissima; Productivity

Red-Breasted Merganser as a Breeding Bird in the Southwest Netherlands 1987-1991 - Meininger, P. L.; De Kraker, K. (Limosa, 1992)
Until 1977, Red-breasted Mergansers were found breeding at least twelve times in The Netherlands, always in the Wadden Sea area. Between 1977 and 1991 this species has bred annually in the Delta area of the SW-Netherlands, with a maximum of 11-12 pairs in 1988 (table 1). In this area Red-breasted Mergansers breed along recently dammed sea-arms, along fresh waters as well as along salt waters. Considering the fact that more areas will develop into potentially suitable breeding sites in the near future, a further increase in breeding numbers is expected.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Mergus serrator; Red-breasted merganser

Birds as victims of marine oil pollution - Meissner, Wlodzimierz (Wiadomosci Ekologiczne)
Oil enters the marine environment from different sources: from vessels, pipelines and offshore exploration platforms. Amount of oil spills entering marine environment decreases gradually, but oil slicks are still significant danger for marine animals, also for birds. Oil spills have resulted in the death of a large number of seabirds (Table I), which are very sensitive to both internal and external affects of crude oil and its refined products. The overall result of efforts to rehabilitate oiled birds is poor.In many countries the extent of chronic oil pollution along a given shoreline is assessed by conducting systematic beached bird surveys, and determining the number and percentage of birds found that are oiled. The percentage of found oiled birds is considered to indicate the risk to birds of becoming oiled at sea, and thus to represent between-year fluctuations in the amount of oil spilled in marine environment. Moreover, species structure of oiled birds indicates the zone in which oil was spilled. Occurrence of seaducks or auks among victims of oil pollution suggests that spill entered sea waters far from the coastline, where these species are more abundant. On the other hand, dominance of swans, dabbling ducks and coots with absence of seaducks and auks indicates that source of pollution was localised close to the shoreline.Researches conducted along the Polish coast showed, that the amount of oil in marine waters of Polish Baltic zone was much lower that 30 years ago (Fig. 1).
Keywords: Sea Ducks - General; Contaminants

Seasonal changes in numbers and distribution of the Long-tailed Duck Clangula hyemalis, Common Scoter Melanitta nigra and Velvet Scoter M. fusca near the Cape Rozewie - Meissner, Wlodzimierz (Ornis Polonica, 2010)
Seasonal changes in numbers and distribution of the Long-tailed Duck Clangula hyemalis, Common Scoter Melanitta nigra and Velvet Scoter M. fusca near the Cape Rozewie. In 2003-2004 a study was conducted aiming to assess the seasonal changes in number and distribution of the three common sea-duck species. The research was carried out on the Baltic Sea between Bialogora and Wladystawowo in the two zones: coastal and open-sea zone. Birds were counted from a ship along the same routes. The number of Long-tailed Ducks Clangula hyemalis was the highest in autumn (maximum 42000 incl.), and subsequently declined. The species reached high numbers in both zones. The Common Scoter Melanitta nigra ocurred mostly in coastal zone. Its number fluctuated considerably throughout the season, and reached a peak of 3300 Md. (in both zones) on 5th April 2004. The Velvet Scoter M. fusca was much more abundant in open-sea zone, and reached a peak in autumn (9500 id.). In autum the highest densities of the clucks were found in a narrow belt of shallow waters of coastal zone, while in winter and spring most birds were concentrated in north-eastern part of the studied area with deeper waters. The most plausible reason for the desertion of coastal-zone was over-exploitation of mussel populations, which constitute the main food of the clucks. Deeper waters in open-sea zone offer high densities of benthic organisms, although diving there is more costly in terms of energy. Changes in the numbers of Long-tailed Ducks could result from both the end of autumn migration and movements of some birds to open-sea zone.
Keywords: Abundance, Distribution, and Trends; Melanitta fusca; Nonbreeding Seasons; White-winged Scoter; Clangula hyemalis; Long-tailed Duck; Black Scoter; Melanitta nigra

Changes in the body composition of Velvet Scoters (Melanitta fusca) wintering in the Gulf of Gdansk - Meissner, W.; Fischer, I.; Bzoma, S. (Oceanological and Hydrobiological Studies, 2012)
Times Cited: 0 Meissner, Wlodzimierz Fischer, Izabela Bzoma, Szymon Meissner, Wlodzimierz/A-3657-2008 Meissner, Wlodzimierz/0000-0002-1259-2838 0
Keywords: Melanitta fusca; Nonbreeding Seasons; white-winged Scoter; energetics and Nutrition

Wintering of waterfowl in the Bay of Gdansk in the season 2005/2006 - Meissner, Wlodzimierz; Rydzkowski, Piotr (Notatki Ornitolgiczne, 2007)
The ice cover appeared in January. Till mid-March the ice covered the inner section of the Puck Bay from the Reda river mouth to Kuznica village. In October large number of the Coot Fulica atra was noted. This species showed significant fluctuations in numbers during the last 22 years. Peak numbers of wintering Coots occurred at the turn of the 1980s and 1990s, when a few exceptionally mild winters appeared subsequently. In February the number of the Goldeneye Bucephala clangula reached 30 thousand. 22.7 thousand (76%) of which stayed in the mouth section of the Vistula river. This was the highest winter concentration of this species noted in Poland, which consisted of 5-7% of the European wintering population. Similarly to the previous seasons, the number of wintering Mute Swans Cygnus olor exceeded 5 thousand individuals, which is ca 2% of the population wintering in north-western Europe. The numbers of Goosanders Mergus merganser were also exceptionally large. The results indicate high importance of the western part of the Gulf of Gdansk for wintering waterbirds. In February the coastal zone supported 91800 waterbirds, except gulls. The numbers of gulls at rubbish dumps lower than usual might be a result of organized human disturbance. The number of gulls along the coast remained stable and, with an exception in January 2004, fluctuated at the level of 7-8 thousand individuals.
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons

Wintering of waterfowl on the Bay of Gdansk in the season 2003/2004 - Meissner, Wlodzimierz; Wojcik, Cezary (Notatki Ornitolgiczne, 2004)
The Bay of Gdansk was iced only during the January control, the ice covering the whole inner part of the Puck Bay. A small area in the mouth of the Reda River that was free of ice grouped ca 25 thousand birds; including 19 700 Tufted Ducks Aythya fuligula, 1 200 Coots Fulica atra and 1 200 Mallards Anas platyrhynchos, which constituted respectively 78, 61 and 52% of all representatives of these species observed during this control. In comparison with two preceding seasons, a decline in the abundance of wintering Mute Swans Cygnus olor and Goosanders Mergus merganser was recorded. The number of gulls at the rubbish dumps exceeded considerably the values noted along the shore of the Gdansk Bay. Like in the previous seasons, an absolute dominant in the group concerned was the Herring Gull Larus argentatus.
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons; Common merganser

Populations and breeding performance of divers, geese and ducks at Zackenberg, northeast Greenland, 1995-2005 - Meltofte, Hans (Wildfowl, 2006)
Monitoring at Zackenberg (74 degrees 30'N, 20 degrees 30'W) since 1995 has provided for the first time long-term data on population trends and breeding performance for a number of high-arctic waterbird species in Greenland. Breeding populations of Red-throated Diver Gavia stellata and Long-tailed Duck Clangulahyemalis were relative stable from year to year, whereas breeding success varied with the abundance of Arctic Fox Alopex, lagopus and Collared Lemming Dicrostonyx groenlandicus. Average nest survival in Red-throated Diver was 18% between 1996 and 2005, and at least five pairs produced a total of about 29 potentially fledged young, or at least 0.5 per pair per year-most of them in two years with few Arctic Foxes. Long-tailed Duck bred successfully in only one year, a year with many Arctic Foxes but also much alternative prey in the form of Collared Lemmings. Few pairs of King Eider Somateria spectabilis were found, and these had poor breeding success. Between four and 32 pairs of Barnacle Geese Branta leucopsis brought their goslings into the study area from nearby colonies each year. An average of about 0.6% of the goslings disappeared per day during the fledging period. More than 500 immature Icelandic Pink-footed Geese Anser brachyrhynchus moulted in the study area at the beginning of the study period, but most disappeared after a few years in spite of attempts to protect them from human disturbance. There is some indication that numbers of both Pink-footed Goose and Long-tailed Duck at Zackenberg have declined since the 1960s.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Clangula hyemalis; Long-tailed Duck; King Eider; Somateria spectabilis

Numbers and distribution of waterbirds in the Wadden Sea - Meltofte, Hans; Blew, Jan; Frikke, John; Roesner, Hans-Ulrich; Smit, Cor (Ophelia, 1994)
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General

Intergradation of Eastern American Common Eiders - Mendall, H. L. (Canadian Field-Naturalist, 1980)
Bill measurements were taken of adult females of 3 ssp. of North American common eiders: Somateria mollissima dresseri, S. m. borealis and S. m. sedentaria and also S. m. borealis-S. m. dresseri intergrades, as an aid in recognizing these races. Live birds and fresh specimens were primarily from Labrador, Newfoundland [Canada], and Maine [USA], and museum skins were from various parts of their ranges. Of 4 bill measurements used, the culmen midline length commonly given in avian literature was the least helpful. Total bill length and or the distance from the nostril to the posterior extension of the frontal lobe permitted separation (P < 0.05) of most individuals of the various subspecies and population groups, including intergrades. Facial feather patterns and plumage coloration varied too much to be reliable as criteria for racial identification. Intergradation between S. m. borealis and S. m. dresseri occurs regularly on the central Labrador coast, and S. m. borealis probably also intergrades with other subspecies where their breeding ranges overlap.
Keywords: Taxonomy; Common Eider; Somateria mollissima; Physiology

Identification of Eastern Races of the Common Eider - Mendall, H. L. (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: Taxonomy; Common Eider; Somateria mollissima

Nesting by Injured Common Eiders Somateria-Mollissima-Dresseri - Mendall, H. L.; Hutchinson, A. E.; Owen, R. B. (Wilson Bulletin, 1984)
Keywords: Breeding Season; Common Eider; Somateria mollissima

Interactions between shorebirds and benthic invertebrates at Culbin Sands lagoon, NE Scotland: Effects of avian predation on their prey community density and structure - Mendonca, V. M.; Raffaelli, D. G.; Boyle, P. R. (Scientia Marina, 2007)
Mendonca, Vanda Mariyam Raffaelli, David George Boyle, Peter R.

Dynamics of coastal meta-ecosystems: the intermittent upwelling hypothesis and a test in rocky intertidal regions - Menge, B. A.; Menge, D. N. L. (Ecological Monographs, 2013)
Menge, Bruce A. Menge, Duncan N. L.

The shivering response during cross-circulation in the common eider duck (Somateria mollissima) - Mercer, J. B.; Hammel, H. T. (Acta Physiologica Scandinavica, 1993)
The possible role of humoral factors in the control of shivering in the common eider duck (Somateria mollissima) was investigated using a cross-circulation technique. Pairs of animals were coupled so that the arterial system of one animal was connected to the venous system of the other. The rate of blood transferral was 12.8 ml min-1. By adequate heparinization of the extracorporal blood supply, cross-circulation could be maintained for periods of up to 12 h. The temperature of blood entering each animal (T-inlet) was controlled by heat exchangers. During control experiments T-inlet was maintained at a temperature close to normal body temperature. During cooling experiments T-inlet was maintained at c. 20 degree C. Changes in metabolic heat production and oesophageal temperature in response to blood cooling were measured in cross-circulated pairs of animals cooled simultaneously or individually. Based on analysis of the metabolic responses under the different experimental situations, no evidence was found to indicate that blood-borne substances are involved in the shivering response in these animals.
Keywords: Common Eider; Somateria mollissima; Physiology

A helicopter-based survey of waterfowl broods in central Ontario - Merendino, M. T.; Ankney, C. D.; Ross, R. K. (Canadian Field-Naturalist, 2000)
The Precambrian shield region of central Ontario supports numerous breeding waterfowl, but only localized attempts to document broad production have been undertaken. During summers of 1990 and 1991, we conducted brood surveys, via helicopter, on 13 100-km2 (10 km X 10 km) survey plots. The most common broods were Mallard, Black Duck, Wood Duck, Hooded Merganser, and Ring-necked Duck. Observations of these species were in proportion to, or greater than, expected frequencies compared to abundance of breeding pairs. Class IIb-III brood sizes for all species were similar to those reported from ground surveys in other areas of eastern Canada and the United States. Peak hatching for all species occurred from 1 June to 15 July. Based on numbers of breeding waterfowl and the general agreement between brood and pair ratios, considerable waterfowl production likely occurs in central Ontario. We suggest that brood surveys in central Ontario start no earlier than 25 June and end by 25 July. Surveys are expensive, so effort should be stratified based on breeding pair densities. For cost-effectiveness, a single survey in late July may provide a reliable production index for both early and late-nesting species.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Hooded Merganser; Lophodytes cucullatus

Evidence of population decline in common eiders breeding in Western Greenland - Merkel, Flemming Ravn (Arctic, 2004)
In the Arctic, there is great concern for several eider populations, including the northern common eider (Samateria mollissima borealis) breeding in Canada and Greenland. In 1998-2001, extensive ground surveys were conducted on 937 potential nesting islands in West Greenland, covering most of the districts of Ilulissat, Uummannaq, and Upernavik (69degree15' N to 74degree05'N). On 216 islands within 106 eider colonies, 4097 468 active nests were identified. In 15 colonies where comparable and well-documented surveys were conducted approximately 40 years ago, the study shows a population decline of 81% (from 3361 to 624 nests). A rough comparison shows that of 51 eider colonies surveyed in 1920, 1960, or 1965, 71% either were gone or had declined in breeding numbers when resurveyed in 1998-2001. At the colony level, the 1998-2001 surveys revealed large year-to-year variations in nesting numbers. The reason for the overall decline is not clear. However, there is circumstantial evidence that harvest of common eiders in West Greenland is a key factor. The results urgently call for more cautious management of the northern common eider population.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Common Eider; Somateria mollissima

Impact of hunting and gillnet fishery on wintering eiders in Nuuk, southwest Greenland - Merkel, Flemming Ravn (Waterbirds, 2004)
Commercial harvests of the Common Eider (Somateria mollissima) and King Eider (S. spectabilis) was studied at the local market in Nuuk (southwest Greenland) during the hunting season (Oct-May) in 2000 and 2001. The goal was to quantify composition (species, sex and age), sources (hunting or bycatch), and spatio-temporal distribution of the harvest. Hunting within 30 km of the city was the source of 98% of all eiders sent to market from October until March. In contrast, bycatch in gillnets accounted for 52% of the eiders brought to the market in March and April. In April, most bycatch were from remote fjord habitat;. which seem to hold a high proportion of adult Common Eiders. As measured by the removal of potential reproductive eiders, the spring harvest (April and May) was critical for the Common Eider, while the impact of harvest was highest during midwinter (January and February) for the King Eider. Sympatric distributions within hunting areas complicate management of both specie. Spring hunting and gillnet bycatch are of high management concern.
Keywords: Conservation; Common Eider; Nonbreeding Seasons; Somateria mollissima; King Eider; Somateria spectabilis

Evidence of Recent Population Recovery in Common Eiders Breeding in Western Greenland - Merkel, Flemming R. (Journal of Wildlife Management, 2010)
Severe population declines were reported for common eiders (Somateria mollissima) in western Greenland over the period 1960-2000. A monitoring program, concurrent with more restrictive hunting regulations on common eiders, revealed breeding numbers increasing by 212%, from 2,558 active nests in 2000 to 7,982 nests in 2007. Though it was not possible to directly link harvest reduction and population growth in West Greenland, a similar increase in breeding numbers in Canada was correlated with the harvest reduction in Greenland and linked to increasing adult survival and recruitment of first-time breeders, and a similar explanation is suggested for West Greenland. The study emphasizes that appropriate restrictions in hunting can be efficient in wildlife management and that common eiders can sustain dramatic rates of increase during population regrowth. It also shows that cost-efficient monitoring programs can be established through cooperation with local residents.
Keywords: Conservation; Breeding Season; Abundance, Distribution, and Trends; Common Eider; Somateria mollissima

Effect of embedded lead shot on body condition of common eiders - Merkel, Flemming R.; Falk, Knud; Jamieson, Sarah E. (Journal of Wildlife Management, 2006)
During waterfowl hunting a large number of birds are shot but not instantly killed. Some will die within a few days as a direct consequence of heavy injuries, whereas another proportion is only lightly injured and will survive for an extended period of time although their survival may still be affected. We predicted that embedded body shot (when not instantly lethal) will cause reduced body condition among common eiders (Somateria mollissima), as we assumed such birds to be physical disadvantaged (e.g., as to mobility and foraging) from their injuries. Among birds collected during 3 winters (2000-2002) by Inuit hunters and fishermen in Nuuk, southwest Greenland, we X-rayed and dissected 762 common eiders to extract information about embedded lead shot and body condition. After adjusting for structural body size, year and date of sampling, habitat, and sampling method, we found that embedded lead shot had a significant effect on juvenile body condition. Wounded juvenile birds carried on average 19% less fat than unwounded juveniles. In accordance with a priori predictions, we did not detect an impact of wounding on the body condition of immature and adult birds. For most of these older birds, the shooting incidence took place > 1 year before they were collected, and the insignificant test results indicated the absence of a long-term effect on body condition once birds survived the initial effect of wounding. For juvenile birds, the wounding effect most likely added to other causes of mortality; however, additional knowledge about natural mortality is required to estimate the net consequence on population dynamic.
Keywords: Conservation; Common Eider; Nonbreeding Seasons; Somateria mollissima; Energetics and Nutrition

The diet of common eiders wintering in Nuuk, Southwest Greenland - Merkel, Flemming R.; Jamieson, Sarah E.; Falk, Knud; Mosbech, Anders (Polar Biology, 2007)
Southwest Greenland provides wintering grounds for 70% (similar to 460,000) of the northern common eider (Somateria mollissima borealis) population. From 241 gullet samples (esophagus and proventriculus content) collected over three winters (1999-2002) near Nuuk, we identified 39 species consumed by the eiders. In contrast to studies elsewhere, fresh mass of the diet was dominated by soft-bottom species: the bivalve Mya eideri (32.8%) and the polychaete Pectinaria spp. (24.2%). The hard-bottom blue mussel (Mytilus edulis), usually the dominant prey of common eiders, was only the fourth most important diet species (7.5%). Overall, bivalves accounted for 56% of the diet. Twenty-seven prey species were minor foods with aggregate fresh mass of only 5.5%. Diets of males and females were similar, whereas juveniles consumed greater mass of crustaceans and less of bivalves. Diet diversity was higher in mid-winter than late winter, and higher in coastal habitats than in fjords. Within one important wintering area the results indicate that optimal size of blue mussels may be depleted over winter.
Keywords: Common Eider; Nonbreeding Seasons; Somateria mollissima; Trophic Interactions

Light-induced bird strikes on vessels in Southwest Greenland - Merkel, F. R.; Johansen, K. L. (Marine Pollution Bulletin, 2011)
Times Cited: 2 Merkel, Flemming Ravn Johansen, Kasper Lambert Merkel, Flemming/J-7409-2013 2
Keywords: Conservation; sea ducks

Wintering seabirds in south-west Greenland, 2017 - Merkel, F. R.; Johansen, K. L.; Nielsen, R. D.; Petersen, I. K.; Sterup, J.; Mosbech, A. (POLAR RESEARCH, 2019)
The South-west Greenland Open Water Area is an internationally important wintering area for seabirds in the North Atlantic. Nearly two decades after the area was last surveyed, we conducted a replicate aerial survey in March 2017 to update information on the distribution and abundance of seabirds. With a total effort of about 5800 km, we covered the coastal area from Aasiaat (69 degrees N) to Kap Farvel (60 degrees N), 56% of the open water area in the fjords, and the offshore bank, Store Hellefiskebanke. Line transect survey methodology was used except in the fjords, which were censused by total counts. By means of distance sampling analyses, the abundances of the dominant species were estimated to be roughly 1100 000 king eiders (Somateria spectabilis), 443 000 common eiders (Somateria mollissima), 42 000 long-tailed ducks (Clangula hyemalis) and 76 000 Iceland gulls/glaucous gulls (Larus glaucoides/Larus hyperboreus). For the great black-backed gull (Larus marinus), great cormorant (Phalacrocorax carbo), mallard (Anas platyrhynchos) and red-breasted merganser (Mergus serrator), we present the first winter population estimates for the area (6100, 7700, 7600 and 3200 individuals, respectively). Areas around Kangaatsiaq, Nuuk and Julianehabsbugten were identified as key wintering sites, as was Store Hellefiskebanke which held 99% of the king eiders. For all species assessed in 1999, abundance in the coastal survey area was considerably lower in 2017. In some cases, this may be due to changes in distribution patterns. However, for thick-billed murre (Uria lomvia), long-tailed duck and black-legged kittiwake (Rissa tridactyla), the reduced coastal abundances coincide with declining breeding populations.
Times Cited in Web of Science Core Collection: 4 Total Times Cited: 4 Cited Reference Count: 60
Keywords: common eider; COMMON EIDERS; ABUNDANCE; MOVEMENTS; king eider; CLIMATE; MARINE BIRDS; POPULATIONS; seaducks; distribution and abundance; FLUCTUATIONS; International seabird wintering area; MURRE URIA-LOMVIA; winter population status

Diurnal and Nocturnal Feeding Strategies in Common Eiders - Merkel, Flemming Ravn; Mosbech, Anders (Waterbirds, 2008)
Feeding activity of wintering Common Eiders (Somateria mollissima) was conducted in Southwest Greenland. Behavioral observations were made at two wintering sites, a fjord habitat and an outer coastal habitat, at which habitat characteristics and human activities differed considerably. In the coastal area where hunting and fishing was common and foraging typically occurred 0.5 to one km from the shore eiders were identified as primarily diurnal feeders. They also foraged during twilight periods, but only rarely at night. In constrast, in the fjord where human disturbance was rare and foraging occurred very close to the shore (< 50 m) adult ciders fed only during twilight and at flight. During daytime, birds gathered in large communal roosts in open water away front feeding areas. Occasionally, feeding was initiated by juveniles during daytime, but was discontinued due to interactions with White-tailed Eagles (Haliaeetus albicilla groenlandicus) and suggests that nocturnal feeding is an anti-predator mechanism. More experienced adult birds in the fjord did not attempt feeding during daylight hours. Large Communal roosts observed at deep waters during previous aerial surveys suggest that nocturnal feeding maybe common throughout the fjords in Southwest Greenland. Received 10 January 2007 accepted 1 April 2007.
Keywords: Behavior; Common Eider; Nonbreeding Seasons; Somateria mollissima; Habitat

Winter seabird distribution and abundance off south-western Greenland, 1999 - Merkel, Flemming Ravn; Mosbech, Anders; Boertmann, David; Grondahl, Louise (Polar Research, 2002)
South-western Greenland constitutes an internationally important wintering area for many seabird species. Several species of management concern have a predominantly near-coastal distribution, though available information about seabird numbers is mostly confined to offshore waters. Here we report on extensive aerial surveys conducted in March 1999, covering the coastal waters (up to 15-20 km from the mainland coast) and fjords of south-west Greenland. The most widespread and numerous species were estimated as 463 000 common eiders (Somateria mollissima), 153 000 king eiders (S. spectabilis), 125 000 thick-billed murres (Uria lomvia), 94 000 long-tailed ducks (Clangula hyemalis), and 12 000 black guillemots (Cepphus grylle). A total of 19 bird species were recorded. The estimates for common eider and long-tailed duck approximately represent the entire winter population in south-western Greenland while estimates for the other species represent only an unknown proportion since their distribution continues further offshore. Waters around Nuuk and within the Julianehabsbugten (Julianehab Bay) area were identified as areas of high seabird density. A large proportion of the common eider population was aggregated in the fjord systems (22%), calling attention to the importance of fjords for this species. In contrast, pelagic seabird species appear to be absent from the fjords. The large winter population of common eider reveals the importance of south-western Greenland as a key wintering area for the eastern Canadian breeding population. The western Greenland breeding population is the only other contributor, probably amounting to no more than 15 000 pairs.
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons

The diet of king eiders wintering in Nuuk, Southwest Greenland, with reference to sympatric wintering common eiders - Merkel, Flemming R.; Mosbech, Anders; Jamieson, Sarah E.; Falk, Knud (Polar Biology, 2007)
Coastal and offshore waters of Southwest Greenland are internationally important wintering areas for king eiders (Somateria spectabilis) breeding in eastern Canadian Arctic and in northwestern Greenland. This paper presents the first assessment of their winter diet. Based on esophageal-proventricular samples from 26 females (13 juveniles and 13 older birds) and 15 males (11 juveniles and four older birds) collected in 2000-2002 (November-May) in coastal waters of Nuuk, we identified 28 prey species. The diet consisted of almost equal proportions (aggregate fresh mass) of polychaetes, echinoderms, crustaceans and molluscs. The dominant prey species were Pectinaria spp. (26.8%), Strongylocentrotus droebachiensis (18.4%), Mya eideri (11.2%) and Hyas araneus (9.7%). The polychaetes have previously been identified as important prey for eiders in Greenland, but apparently not outside Greenland. Compared with a diet study of common eiders Somateria mollissima from the same wintering area, the king eiders consumed significantly less bivalves and significantly more echinoderms. This difference corresponded with observations that common eiders were feeding in shallow waters, while king eiders were feeding in deeper waters farther from the shore. Benthic surveys are needed to confirm that diet corresponds with prey availability.
Keywords: Common Eider; Nonbreeding Seasons; Somateria mollissima; King Eider; Somateria spectabilis; Trophic Interactions

Common Eider Somateria mollissima feeding activity and the influence of human disturbances - Merkel, Flemming Ravn; Mosbech, Anders; Riget, Frank (Ardea, 2009)
We studied the impact of human disturbances on the feeding activities of Common Eiders Somateria mollissima wintering in Southwest Greenland. Eider activity and human disturbances (fast moving, open boats) were recorded during 9 days of observations in mid and late winter 2002. When most heavily disturbed, the feeding activity in the study area was reduced up to 60% on a daily basis. At the same time locomotion activity tripled. Logistic regression analyses showed that eiders attempted to compensate for lost feeding opportunities by rescheduling more feeding to periods where feeding conditions were relatively less profitable with respect to other variables. When undisturbed, eiders avoided feeding during high tide and intensified feeding at the start and at the end of the day, but these tendencies were levelled out if eiders were disturbed. When disturbed, the time interval and the distance to the last disturbance were both significant explanatory variables for the feeding activity. There was a cumulative effect of repeated disturbances on the feeding activity if disturbances were close in time and space (<1 h, <1 km). The day with the highest number of disturbances coincided with observations of nocturnal feeding the following night and may indicate that a critical threshold of disturbances was reached where eiders could not rely on a diurnal feeding strategy.
Keywords: Conservation; Behavior; Common Eider; Nonbreeding Seasons; Somateria mollissima

Local movements, home ranges and body condition of Common Eiders Somateria mollissima wintering in Southwest Greenland - Merkel, Flemming R.; Mosbech, Anders; Sonne, Christian; Flagstad, Annette; Falk, Knud; Jamieson, Sarah E. (Ardea, 2006)
We examined local movements, home ranges and body condition of wintering Northern Common Eiders Somateria niollissima borealis in Southwest Greenland from late winter until spring migration in 2000 and 2001. At key marine habitats at coastal areas and in the inner fjord system of Nuuk, we implanted 33 Eiders with satellite transmitters and collected Eider carcasses for body condition analyses. Most Eiders exhibited strong site fidelity during the study period with a mean 95% home range size of 67.8 km(2) and a mean core area (50%) of 8.1 km2. Diurnal movements peaked at dawn and dusk when birds presumably moved between feeding areas and roosting sites. Roosting occurred near daytime activity centres, on average 1.7 kin apart. Among birds marked at coastal habitats only between 8% and 29% also used the inner fjord habitats, despite high levels of hunting at the coastal area. Birds that did move to the inner fjord system did not return to the coastal area. These findings accentuate the need for managing wintering Common Eiders in Southwest Greenland also at a local scale, taking site fidelity into account. The body condition of adult fjord birds was either equal or superior to that of coastal birds. However, within-years and betweenyears-variation in body condition were larger for fjord birds, suggesting that they were challenged by a higher unpredictability at the local scale. Observations indicate that differences in habitat characteristics and the behaviour of avian predators may limit the exchange of Eiders between the coastal area and the inner fjord system. Our study suggests that often Eiders build up body reserves for the breeding season elsewhere; in three of four cases adult body condition declined from late winter to early spring.
Keywords: Common Eider; Nonbreeding Seasons; Somateria mollissima; Dispersal; Energetics and Nutrition

Plasticity in timing of avian breeding in response to spring temperature differs between early and late nesting species - Messmer, D. J.; Alisauskas, R. T.; Poysa, H.; Runko, P.; Clark, R. G. (SCIENTIFIC REPORTS, 2021)
Plasticity for breeding dates may influence population vulnerability to climate change via phenological mismatch between an organism's life cycle requirements and resource availability in occupied environments. Some life history traits may constrain plasticity, however there have been remarkably few comparisons of how closely-related species, differing in key traits, respond to common phenology gradients. We compared population- and individual-level plasticity in clutch initiation dates (CID) in response to spring temperature among five duck species with early- to late-season nesting life histories. Plasticity was strongest in females of the earliest breeding species (common goldeneye [Bucephala clangula], mallard [Anas platyrhynchos], and gadwall [Mareca strepera]), whereas late-nesting lesser scaup (Aythya affinis) and white-winged scoter (Melanitta fusca deglandi) did not respond. These results contrast with previous work in other bird families that suggested late-breeders are generally more flexible. Nevertheless, late-breeding species exhibited annual variation in mean CID, suggesting response to other environmental factors unrelated to spring temperature. Goldeneye and gadwall females varied in their strength of individual plasticity ('individualxenvironment' interactions) and goldeneye and scoter females showed evidence of interannual repeatability of CID. Fitness consequences of CID plasticity in response to spring phenology, including trophic mechanisms and population consequences, warrant investigation.
Times Cited in Web of Science Core Collection: 3 Total Times Cited: 3 Cited Reference Count: 56
Keywords: CLIMATE-CHANGE; PATTERNS; SELECTION; LESSER SCAUP; MIGRATION; DATE; GROWTH; MELANITTA-FUSCA-DEGLANDI; PHENOTYPIC PLASTICITY; REPRODUCTIVE-PERFORMANCE

Trophic position influences the efficacy of seabirds as metal biovectors - Michelutti, Neal; Blais, Jules M.; Mallory, Mark L.; Brash, Jaclyn; Thienpont, Joshua; Kimpe, Lynda E.; Douglas, Marianne S. V.; Smol, John P. (Proceedings of the National Academy of Sciences of the United States of America, 2010)
Seabirds represent a well documented biological transport pathway of nutrients from the ocean to the land by nesting in colonies and providing organic subsidies (feces, carcasses, dropped food) to these sites. We investigated whether seabirds that feed at different trophic levels vary in their potency as biovectors of metals, which can bioaccumulate through the marine foodweb. Our study site, located on a small island in Arctic Canada, contains the unique scenario of two nearby ponds, one of which receives inputs almost exclusively from upper trophic level piscivores (Arctic terns, Sterna paradisaea) and the other mainly from lower trophic level molluscivores (common eiders, Somateria mollissima). We used dated sediment cores to compare differences in diatoms, metal concentrations and also stable isotopes of nitrogen (delta N-15), which reflect trophic position. We show that the seabirds carry species-specific mixtures of metals that are ultimately shunted to their nesting sites. For example, sediments from the tern-affected pond recorded the highest levels of delta N-15 and the greatest concentrations of metals that are known to bioaccumulate, including Hg and Cd. In contrast, the core from the eider-affected site registered lower delta N-15 values, but higher concentrations of Pb, Al, and Mn. These metals have been recorded at their greatest concentrations in eiders relative to other seabirds, including Arctic terns. These data indicate that metals may be used to track seabird population dynamics, and that some metal tracers may even be species-specific. The predominance of large seabird colonies on every continent suggests that similar processes are operating along coastlines worldwide.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Trophic Interactions

Breeding Biology of Cackling Geese and Associated Species on the Yukon Kuskokwim Delta Alaska USA - Mickelson, P. G. (Wildlife Monographs, 1975)
Keywords: Breeding Season; Somateria fischeri; Spectacled Eider

The effects of disturbance caused by boating on survival and behaviour of velvet scoter Melanitta fusca ducklings - Mikola, Juha; Miettinen, Mika; Lehikoinen, Esa; Lehtila, Kari (Biological Conservation, 1994)
We studied the consequences of human disturbance and gull predation on brood survival of velvet scoter Melanitta fusca in the Archipelago of South-West Finland in 1990 and 1991. Each brood was exposed to disturbance by boats on average 8.5 times a day in 1990 and 3.5 times a day in 1991. Disturbance lengthened the swimming distances of ducklings and reduced the time used for feeding. Broods disturbed more frequently than average were smaller than those disturbed less frequently. At least 60% of ducklings died before the age of three weeks. The common predators of ducklings in the study area are the herring gull Larus argentatus and the great black-backed gull Larus marinus. The daily predation rate by gulls on velvet scoter ducklings was 4.7%, which means that 56% of ducklings are caught by gulls during the first three weeks. The frequency of gull attacks was 3.5 times higher in disturbed than in undisturbed situations.
Keywords: Conservation; Behavior; Breeding Season; Melanitta fusca; White-winged Scoter; Productivity; Trophic Interactions

Submerged vegetation and the variation in the autumn waterfowl community at Lake Takern, southern Sweden - Milberg, Per; Gezelius, Lars; Blindow, Irmgard; Nilsson, Leif; Tyrberg, Tommy (Ornis Fennica, 2002)
We analysed data from 25 years of standardised mid-September counts of waterfowl at eutrophic Lake Takern, southern Sweden. For eight species, counts were compared with a national index constructed from similar counts at numerous lakes and coastal sites. For Crested Grebes and Mute Swans there was a correlation between counts at Lake Takern and the national index, suggesting that they simultaneously vary in number over a large geographic area. Indirect gradient analysis (PCA) revealed a strong temporal trend in the data, which was covaried out in a partial PCA to expose residual patterns. This ordination separated Pochards and Tufted Ducks at on end of the first axis from Cormorants and Goosanders at the other. A direct gradient analysis, with biomass of submerged macrophytes (recorded for 14 of the 25 years) as the sole environmental variable, showed that bird species composition varied significantly with plant biomass. The piscivores, Cormorants and Goosanders, were abundant in years with small amounts of plant biomass, while several species were most abundant in years with large amounts. Our analyses suggest that the abundance of submerged macrophytes is an important determinant of the bird community composition in eutrophic lakes.
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons; Common merganser; Mergus merganser; Habitat

Polycyclic aromatic hydrocarbon exposure in Steller's eiders (Polysticta stelleri) and harlequin ducks (Histronicus histronicus) in the eastern Aleutian Islands, Alaska, USA - Miles, A. Keith; Flint, Paul L.; Trust, Kimberley A.; Ricca, Mark A.; Spring, Sarah E.; Arrieta, Daniel E.; Hollmen, Tuula; Wilson, Barry W. (Environmental Toxicology and Chemistry, 2007)
Seaducks may be affected by harmful levels of polycyclic aromatic hydrocarbons (PAHs) at seaports near the Arctic. As an indicator of exposure to PAHs, we measured hepatic enzyme 7-ethoxyresorufin-O-deethylase activity (EROD) to determine cytochrome P4501A induction in Steller's eiders (Polysticta stelleri) and Harlequin ducks (Histronicus histronicus) from Unalaska, Popof, and Unga Islands (AK, USA) in 2002 and 2003. We measured PAHs and organic contaminants in seaduck prey samples and polychlorinated biphenyl congeners in seaduck blood plasma to determine any relationship to EROD. Using Akaike's information criterion, species and site differences best explained EROD patterns: Activity was higher in Harlequin ducks than in Steller's eiders and higher at industrial than at nonindustrial sites. Site-specific concentrations of PAHs in blue mussels ([Mytilus trossilus] seaduck prey; PAH concentrations higher at Dutch Harbor, Unalaska, than at other sites) also was important in defining EROD patterns. Organochlorine compounds rarely were detected in prey samples. No relationship was found between polychlorinated biphenyl congeners in avian blood and EROD, which further supported inferences derived from Akaike's information criterion. Congeners were highest in seaducks from a nonindustrial or reference site, contrary to PAH patterns. To assist in interpreting the field study, 15 captive Steller's ciders were dosed with a PAH known to induce cytochrome P4501A. Dosed, captive Steller's ciders had definitive induction, but results indicated that wild Steller's eiders were exposed to PAHs or other inducing compounds at levels greater than those used in laboratory studies. Concentrations of PAHs in blue mussels at or near Dutch Harbor (similar to 1,180-5,980 ng/g) approached those found at highly contaminated sites (similar to 4,100-7,500 ng/g).
Keywords: Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Contaminants; Polysticta stelleri; Steller's eider

Long-term decline and geographical variation in the numbers of moulting Common Eiders Somateria mollissima in Shetland - Miles, W.; Mellor, M.; Gear, S.; Harvey, P. V.; Tyler, G. (BIRD STUDY, 2021)
Capsule: Numbers of moulting Common Eiders Somateria mollissima counted in Shetland during surveys from 1977 to 2019 decreased from approximately 14,500 to an estimated 3600 individuals, a 75% population decline. Aims: To report results of extensive surveys of Eiders across Shetland during the annual complete moult period, review historical surveys, and evaluate long-term population changes and the possible underlying causes for change. Methods: Extensive areas of coastal Shetland were surveyed for Eiders during the annual moult period from July to September, every one to five years from 1977 to 2019. Spatial sampling was variable between surveys from 1977 to 1993 but more systematic and standardised during all surveys from 1996 to 2019. Overall population change, changes in numbers of birds within areas categorised as either exposed or sheltered coast, and change in the proportion of adult males to females/juveniles were assessed. Results: Surveys from 1977 to 1993 indicated a 55% decrease, from approximately 14,500-6500 individuals, and surveys from 1996 to 2019 showed a 45% decrease, from an estimated 6700-3600 individuals, indicating an overall population decrease of approximately 75% from 1977 to 2019. From 1996 to 2019, Eider numbers decreased in areas of exposed coast by approximately 90% but increased by at least 70% in the more sparsely populated sheltered areas, and the overall proportion of adult males to females/juveniles reduced by one-third. Conclusion: From 1977 to 2019, a substantial decline of approximately 75% occurred in the Shetland Eider population at the time of moult. Shetland Eiders are not S. m. mollissima but morphologically and genetically akin to S. m. faeroeensis, the Faroese subspecies, the rarest subspecies worldwide, so this decline is of high conservation concern. Causes of the decline largely remain unknown, but ecological datasets on Shetland Eiders are few and detailed studies, including remote tracking of individuals' movements throughout the year, would be worthwhile.
Times Cited in Web of Science Core Collection: 0 Total Times Cited: 0 Cited Reference Count: 44

Allometry, bilateral asymmetry and sexual differences in the vocal tract of common eiders Somateria mollissima and king eiders S-spectabilis - Miller, Edward H.; Williams, Joni; Jamieson, Sarah E.; Gilchrist, H. Grant; Mallory, Mark L. (Journal of Avian Biology, 2007)
Intraspecific sexual differences, high variation, and positive allometry of sexually-selected external display structures are common. Many sexually-selected anatomical specializations occur in the avian vocal tract but intraspecific variation and allometry have been investigated little. The tracheal bulla bulla syringealis occurs in males of most duck species. We quantified variation and size-scaling of the bulla, plus sexual differences in size of trachea, bronchi, and vocal muscles, for 62 common eiders Somateria mollissima and 51 king eiders S. spectabilis. Trends were similar in both species. Bullar ossification and definitive size occurred early in life: bullar size did not differ between first-year and older males. Bullar size did not vary more than size of other body parts (CVs of 3.4-7.0% for bullar length and breadth). Bullar size scaled to body size with negative allometry or isometry. Vocal muscles were 10-50% thicker in males than females, a much greater sexual difference than in body size (CVs of 3-6% on linear body-size variables). Vocal muscles were larger on the left side in both sexes and bilateral asymmetry was slightly more pronounced in males. Low variation and a trend towards negative allometry suggest that bullar size is under stabilizing selection; if bullar size affects vocal attributes of voice, then the latter cannot be condition-dependent. We recommend comparative research on vocal communication, vocal individuality and vocal-tract anatomy and function in eiders and other ducks.
Keywords: Common Eider; Somateria mollissima; Physiology; King Eider; Somateria spectabilis

Red-breasted mergansers in an urban winter habitat - Miller, Jeffrey Boone (Journal of Field Ornithology, 1996)
During the winters of 1991-95, I determined population densities, proportions of adult males, activity budgets, and foraging by Red-breasted Mergansers (Mergus serrator) during mid-day on the urbanized inner harbor at Boston Massachusetts. Red-breasted Mergansers arrived at Boston in mid-to-late December, reached peak densities of 1-3/ha in late January or early February, and left by the first week of April. The mid-winter proportion of adult males was 60-80% in the three winters of 1991-92 through 1993-94, but only approximately 30% during the warmer than average winter of 1994-95. Foraging, preening, and alert/swimming each accounted for about 20-30% of observations. Red-breasted Mergansers surfaced with and ingested fish after 6.4% of dives, and, when gulls attempted to pirate fish, the mergansers escaped under piers.
Keywords: Behavior; Abundance, Distribution, and Trends; Nonbreeding Seasons; Mergus serrator; Red-breasted merganser

Use of marine vs. freshwater proteins for egg-laying and incubation by sea ducks breeding in Arctic tundra - Miller, M. W. C.; Lovvorn, J. R.; Graff, N. R.; Stellrecht, N. C. (ECOSPHERE, 2022)
Understanding dietary nutrient sources is fundamental to conserving sensitive species, especially as climate change alters food web dynamics. Migratory species that depend on both marine and terrestrial habitats face unique challenges, as the locations and quality of resources in the two realms may respond quite differently to environmental changes, with potential for spatial and temporal carryover effects. For sea ducks (Mergini) that winter at sea but move inland to breed, body size may determine their capacity to store nutrient reserves for later use in alternative habitats. We assessed ultimate sources of protein for reproduction in four sea duck species in northern Alaska: smaller-bodied Long-tailed Ducks and Steller's Eiders (Clangula hyemalis and Polysticta stelleri), and larger-bodied Spectacled and King Eiders (Somateria fischeri and Somateria spectabilis). To assess the relative use of local freshwater foods vs. marine protein for both egg production and body maintenance of incubating females, we measured stable isotopes of carbon and nitrogen in egg membranes, red blood cells, marine and freshwater invertebrates, and vegetation. For egg production, isotope mixing models indicated that proteinaceous egg membranes of all four species were derived mostly (89%-95%) from freshwater foods on the breeding grounds, with broad individual variation in specific prey types selected by the larger species. For incubation, isotopes in red blood cells indicated that body maintenance of females also relied mainly (87%-91%) on freshwater foods in Long-tailed Ducks and Steller's Eiders. However, incubating Spectacled and King Eiders obtained only about 60% of their protein from freshwater foods and the remainder from marine-derived body tissues. The latter strategy allows the larger-bodied species to incubate almost continuously, whereas the smaller species must take more frequent incubation breaks and generally incur higher rates of predation on eggs. Thus, depending on body size, cross-seasonal effects of feeding conditions in marine habitats may strongly influence population processes well after the birds move to inland nesting sites. Although conservation programs on land and sea are often researched, planned, and administered by different agencies and organizations, our results emphasize the need to coordinate marine and land-based efforts for species that integrate conditions across both environments.
Times Cited in Web of Science Core Collection: 1 Total Times Cited: 1 Cited Reference Count: 99
Keywords: climate change; COMMON EIDERS; POPULATION-DYNAMICS; KING EIDERS; LONG-TAILED DUCKS; STABLE-ISOTOPES; sea duck; BODY CONDITION; STELLERS EIDERS; SPECTACLED EIDERS; breeding strategy; cross-seasonal effects; ISOTOPE DISCRIMINATION FACTORS; isotope mixing model; nutrient source; reproductive strategy; SOMATERIA-SPECTABILIS; stable isotopes

Interspecific patterns of trace elements in sea ducks: Can surrogate species be used in contaminants monitoring? - Miller, M. W. C.; Lovvorn, J. R.; Matz, A. C.; Taylor, R. J.; Latty, C. J.; Brooks, M. L.; Hollmen, T. E. (ECOLOGICAL INDICATORS, 2019)
As industrial development, aerial deposition of pollutants, and chemical releases from thawing permafrost increase in the Arctic, there is need to monitor exposure to contaminants in a range of species. Surrogate or bioindicator species are often used to represent groups of taxa and are typically selected for their wide geographic ranges and ease of sampling. However, it is seldom known how well surrogates exemplify different species, ages, or breeding stages in different areas. We examined multiple trace elements in incubating females of five sea duck species (long-tailed ducks Clangula hyemalis, Steller's eiders Polysticta stelleri, spectacled eiders Somateria ftscheri, king eiders S. spectabilis, and common eiders S. mollissima), in pre-laying spectacled eiders, and in brood-rearing female spectacled and king eiders and their ducklings, among four areas on the Arctic Coastal Plain of Alaska, USA. For Se, Cd, and Cu that are probably acquired during the nonbreeding period, Se and Cd in the blood of hens varied appreciably among species, whereas all species appeared to regulate Cu at similar concentrations. Levels of blood Hg and Pb sampled during incubation were inconsistent among species, apparently reflecting variable exposure on breeding areas. During incubation, species of similar body mass had similar patterns of elements. Se, Cu, and Pb differed substantially across the breeding season in spectacled eiders, as well as between ducklings and hens of spectacled and king eiders. Although analysis of feathers avoids invasive sampling, patterns of element concentrations in feathers differed from those in blood. Species of comparable body mass and life history traits sampled at a given site generally had similar concentrations of trace elements in blood, suggesting some utility as surrogates, but still showed regional variation. Our results suggest that for sea ducks, surrogate species of varying body mass and life history traits may not consistently reflect levels of exposure across taxa, or even among congeners or sex-age classes in the same areas. Biomonitoring for contaminants should use species of comparable mass as indicators at small spatial scales, but at the regional scale, should focus on specific taxa of concern.
Times Cited in Web of Science Core Collection: 3 Total Times Cited: 3 Cited Reference Count: 101
Keywords: ALASKA; BEAUFORT SEA; KING EIDERS; Biomonitoring; BODY-MASS; EIDER SOMATERIA-MOLLISSIMA; MARINE BIRDS; SPECTACLED EIDERS; Eiders; FEATHERS; Bioindicators; Contaminants in blood; Contaminants in feathers; FEMALE COMMON EIDERS; MERCURY CONCENTRATIONS; Surrogate species

Trace Elements in Sea Ducks of the Alaskan Arctic Coast: Patterns of Variation Among Species, Sexes, and Ages - Miller, M. W. C.; Lovvorn, J. R.; Matz, A. C.; Taylor, R. J.; Latty, C. J.; Safine, D. E. (Archives of Environmental Contamination and Toxicology, 2016)
Climate change and increasing industrialization in the Arctic call for the collection of reference data for assessing changes in contaminant levels. For migratory birds, measuring and interpreting changes in trace element burdens on Arctic breeding areas require insights into factors such as sex, body size, or wintering area that may modify patterns independently of local exposure. In the Alaskan Arctic, we determined levels of trace elements in liver and kidney of common eiders (Somateria mollissima) and long-tailed ducks (Clangula hyemalis) from the Prudhoe Bay oil field and of king eiders (S. spectabilis) and threatened spectacled eiders (S. fischeri) and Steller's eiders (Polystica stelleri) from near the town of Barrow. Small-bodied Steller's eiders and long-tailed ducks from different locations had similarly low levels of selenium (Se), cadmium (Cd), and copper (Cu), perhaps reflecting high mass-specific rates of metabolic depuration during long spring migrations through areas of low exposure. In larger species, Se, Cd, and Cu concentrations were higher in adults than juveniles suggesting that these elements were acquired in nonbreeding marine habitats. Adult male spectacled eiders had exceptionally high Se, Cd, and Cu compared with adult females, possibly because of depuration into eggs and longer female occupancy of nonmarine habitats. Adult female common eiders and juvenile long-tailed ducks at Prudhoe Bay had high and variable levels of Pb, potentially due to local exposure. Explanations for substantial variations in Hg levels were not apparent. Further research into reasons for differing element levels among species and sexes will help clarify the sources, pathways, and risks of exposure.
Miller, Micah W. C. Lovvorn, James R. Matz, Angela C. Taylor, Robert J. Latty, Christopher J. Safine, David E.
Keywords: Breeding Season; Somateria fischeri; Spectacled Eider; Common Eider; Clangula hyemalis; Long-tailed Duck; Contaminants; Somateria mollissima; King Eider; Somateria spectabilis; Polysticta stelleri; Steller’s Eider

Body Weights and Carcass Composition of the Common Eider - Milne, H. (Wildfowl, 1976)
Keywords: Common Eider; Somateria mollissima; Energetics and Nutrition

Egg formation, brood survival and cost of reproduction as clutch-size-determining factors in common goldeneyes - Milonoff, Markku; Paananen, Pertti (Auk, 1993)
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Productivity

Factors affecting clutch size and duckling survival in the common goldeneye Bucephala clangula - Milonoff, Markku; Poysa, Hannu; Runko, Pentti (Wildlife Biology, 1998)
Female age and condition as well as nesting schedule may affect clutch size and chick survival, which both are important factors affecting the annual reproductive output. Clutch size and chick survival are often interrelated in altricial birds but in precocial species the interrelation is dubious. To study factors affecting clutch size and the survival of ducklings in the common goldeneye Bucephala clangula, we examined ringing-recovery data, supplied by ringers, from seven intensively studied goldeneye populations from different parts of Finland. Due to large sample sizes it was possible to distinguish the effects of interrelated variables, e.g. female age and hatching date. Clutch size was significantly associated with both female age and hatching date; first-time breeders and late breeders had small clutches. Clutch size was not associated with female condition. The recovery rate of ducklings was associated with hatching date (low in late broods) but not with female age, condition or brood size. The natal brood sizes of recruited female ducklings did not differ from annual averages, but the natal hatching date of recruited females was earlier and their mothers were older than annual averages in the populations into which the recruited females were born. The timing of nesting was the most important factor affecting the reproductive output of common goldeneye females in a given year.
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Productivity; Survival

Reproductive performance of Common Goldeneye Bucephala clangula females in relation to age and lifespan - Milonoff, Markku; Poysa, Hannu; Runko, Pentti (Ibis, 2002)
We studied the effects of female age and length of lifespan on reproductive performance in the Common Goldeneye Bucephala clangula, a precocial species with self-feeding chicks. Dependent variables studied were the occurrence of failed nesting attempts and non-breeding years, clutch size, nesting and hatching success, female condition and recovery rate of offspring. To avoid misinterpretations resulting from age-dependent quality changes in the cohorts, individuals with different lifespans were separated in the analyses. There was no evidence that females of different lifespan differed in reproductive strategy. The data revealed no significant differences in nest losses, occurrence of non-breeding years, timing of nesting or clutch size, but the physiological condition of short-lived females was poorer than that of longer living females. This accords with the prediction that poor-quality females invest proportionally more in reproduction than high-quality females and consequently die earlier. The most productive individuals were those that lived longest. The only indication of senescence was the low recovery rate of offspring produced by old females. The last breeding attempt did not differ in any observable respect from the penultimate attempt, implying that the last investment in reproduction was no heavier than the previous one.
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Productivity

Brood rearing costs affect future reproduction in the precocial common goldeneye Bucephala clangula - Milonoff, Markku; Poysa, Hannu; Runko, Pentti; Ruusila, Vesa (Journal of Avian Biology, 2004)
Life-history theory assumes a trade-off between current reproductive effort and future reproductive success. There are a large number of studies demonstrating reproductive trade-offs in different animal taxa, particularly in birds. Most bird studies have focused on the costs of chick rearing in altricial species. These costs have been assumed to be low in precocial species, but this aspect has been little studied. We used long-term individual reproductive data from the common goldeneye Bucephala clangula, an iteroparous precocial duck with uniparental female care, to examine whether brood rearing carries costs that affect future reproductive performance. All females were experienced breeders, and possible differences in female quality were ruled out. We compared within-individual (between-year) changes in clutch size, hatching date and body mass between females that had reared a brood in the previous year and females that had not. It turned out that brood rearing involved a cost in terms of clutch size and hatching date the next year, but not in terms of body mass: females that had reared a brood in the previous year laid relatively smaller clutches and laid relatively later than females that had not reared a brood. Our results show that normal brood rearing in a precocial species involves costs that affect future reproduction.
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye

Brood-size-dependent offspring mortality in common goldeneyes reconsidered: Fact or artifact? - Milonoff, Markku; Poysa, Hannu; Virtanen, Juha (American Naturalist, 1995)
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Survival

Sex-Specific Survival of Adult Common Eiders in Nova Scotia, Canada - Milton, G. R.; Iverson, S. A.; Smith, P. A.; Tomlik, M. D.; Parsons, G. J.; Mallory, M. L. (JOURNAL OF WILDLIFE MANAGEMENT, 2016)
Common eiders (Somateria mollissima) are large sea ducks with a circumpolar distribution and have high cultural significance to sport hunters and indigenous peoples in many countries. Their gregarious habits, including colonial breeding and forming large flocks during migration and winter, make eiders susceptible to environmental stressors during breeding and non-breeding seasons. Our objective was to assess whether low adult survivorship could be contributing to suspected local population declines in Nova Scotia, Canada. We banded molting male and breeding female common eiders along the marine coastline of Nova Scotia and recaptured them in later years. We found that from 1997 to 2011, when males and females were banded, male survival (S) was high (S = 0.92; 95% CI = 0.87-0.95), whereas female survival was approximately 10% lower (S = 0.83; 95% CI = 0.78-0.87) and at a level comparable to what has been reported in other regions of the world where eider populations are thought to be in decline. Recovery rates (f) of harvested male and female eiders were indistinguishable (f = 0.013; 95% CI = 0.010-0.016), suggesting that lower female survival is attributable to factors other than hunting. Supplementary analyses using a longer-term data set for females only (1978-2011) and including live recapture data indicated that female survival rates have not changed markedly during the past 40 years and that the emigration rate from colonies is low (similar to 6%). We conclude that to successfully conserve this population, sources of non-harvest female mortality should be investigated and used to develop targeted management solutions. We speculate that one of those sources of mortality is predation on females at breeding colonies, notably from eagles and mustelids. (C) 2016 The Wildlife Society.
Times Cited in Web of Science Core Collection: 10 Total Times Cited: 10 Cited Reference Count: 65
Keywords: predation; common eider; POPULATION-DYNAMICS; SOMATERIA-MOLLISSIMA; Somateria mollissima dresseri; CONSERVATION; REPRODUCTION; RECOVERY; LONG-TERM; INCREASES; ECOLOGICAL TRAPS; FEMALE EIDERS; Nova Scotia; recovery rate; survival rate; SUSTAINABILITY

Population Status of the Globally Threatened Long-Tailed Duck Clangula hyemalis in the Northeast European Tundra - Mineev, O.; Mineev, Y.; Kochanov, S.; Novakovskiy, A. (DIVERSITY-BASEL, 2023)
Arctic Russia is home to more than 90% of all Long-tailed Ducks in the Clangula hyemalis species from the Western Siberia/Northern Europe population. The breeding population in European Russia was estimated to be about 5 million birds in the 1960s, while today, estimates have declined to 1 million birds. Up until now, the main reasons for the overall population decline of the Long-tailed Duck were related to wintering conditions in the Baltic Sea. Our data indicate that the loss or deterioration of key breeding habitats in the Arctic regions of Russia is one important factor influencing the rapid population decline. Many key breeding habitats of the Long-tailed Duck were completely lost in the Bolshezemelskaya tundra, as this area was transformed into major oil and gas extraction sites. The transformation of these sites increased the disturbance and oil pollution of adjacent habitats, leading to the direct loss of certain key nesting sites and a marked and rapid decline of the breeding population of the Long-tailed Duck in the Bolshezemelskaya tundra. Oil-spills during transportation by sea may also be an important factor of decline in the Long-tailed Duck population. Meanwhile, in the Malozemelskaya tundra, which did not experience oil and gas development, the breeding population over the last decades remained stable. Urgent establishment of new protections in key breeding areas in Arctic Russia, sustainable population management, and new research programs are necessary for the conservation and enhancement of this globally threatened species.
Times Cited in Web of Science Core Collection: 0 Total Times Cited: 0 Cited Reference Count: 37
Keywords: Long-tailed Duck; GILLNET FISHERIES; Northeast European tundra; population status

Tidal Diurnal and Habitat Influences on Common Eider Somateria-Mollissima Rearing Activities - Minot, E. O. (Ornis Scandinavica, 1980)
The rearing activities of the common eider S. mollissima were studied in the Grand Manan Archipelago, New Brunswick, Canada. Tide and time of day were both correlated with a number of different activities. Generally, tide affected physical or biotic aspects of the environment while time of day was related to the internal need to feed. Eiders concentrated along sheltered, rockweed-covered shores, feeding most actively at tides when food was most available but with a concurrent diurnal feeding pattern that had peaks of activity early and late in the day. Tide, time of day and status of the birds interacted in determining the use of various nearshore habitats. Groups of females and young traveled from the nesting islands to rearing areas 5-8 km away. This departure was timed, by tide and time of day, to minimize gull (Larus spp.) predation and to use favorable currents.
Keywords: Behavior; Breeding Season; Common Eider; Somateria mollissima

Effects of predation by fish and wintering ducks on dreissenid mussels at Nanticoke, Lake Erie - Mitchell, J. S.; Bailey, R. C.; Knapton, R. W. (Ecoscience, 2000)
Mitchell, JS Bailey, RC Knapton, RW

Harlequin Ducks in the Eastern United States - Mittelhauser, Glen H. (Waterbirds, 2008)
Harlequin Ducks (Histrionicus histrionicus) arrive along the eastern coast of the United States at traditional wintering grounds from late September to December through early January. Counts in January and February best represent wintering bird numbers. Spring migrants depart from April to May, although from more southerly wintering areas, birds appear to depart in March. Breeding has never been confirmed in the eastern United States. Molting females have been documented in Maine during the fall, but the extent of molting has not been assessed. It is estimated 1,575 to 1,800 Harlequin Ducks wintered in the eastern United States from Maine to North Carolina between the winters of 1997-98 and 2001-02. Over 75% of the birds wintering in the eastern United States were in Maine, primarily in the vicinity of Isle an Haut. Smaller concentrations representing about 18% of the wintering birds in the eastern United States were at locations in Massachusetts and Rhode Island, primarily the Cape Anne region and Martha's Vincyard, Massachusetts and the Sachuest Point region, Rhode Island. South of Rhode Island, Barnegat, New Jersey is the only area that regularly reports counts of over 25 birds. In the Isle an Haut region of Maine, numbers along survey routes have not shown a linear change from 1989-2002, but show a pattern of decline from 1989 to 1993 followed by increases since then. In eastern Maine, population increases are greatest and birds are expanding their winter range into new areas. All Other areas in the eastern United States South of Isle an Haut that regularly report over 50 birds show significant population increases since the 1980s, north-eastern US.
Keywords: Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus

Apparent Survival and Local Movements of Harlequin Ducks Wintering at Isle au Haut, Maine - Mittelhauser, Glen H. (Waterbirds, 2008)
Capture-recapture data from a five-year field study of individually marked Harlequin Ducks (Histrionicus histrionicus) wintering at Isle an Haut, Maine was used to examine patterns in age- and sex-specific apparent survival and local movements. Adult females had lower annual apparent survival probabilities than adult males. Survival probabilities for adult females were lower during the summer season than the winter season. Adult males showed no differences in apparent survival between the summer and winter intervals and survival during the winter season was similar for adult males and females. There was little evidence to Suggest differences in apparent survival between first winter males and females,although sample sizes, especially for first winter females, were small. Annual apparent. survival rates were lower for first winter males than adult males and likely reflected a combination of greater dispersal and higher mortality. Adult males captured in April in the study area disappeared from the study area more than adult males captured in November and may represent spring dispersal of unpaired males searching for mates or individuals from other wintering sites gathering before spring migration. Greater dispersal of adult and first winter males to adjacent wintering sites ill subsequent winters was noted than for adult females.
Keywords: Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Dispersal; Population Dynamics; Survival; SDJV funded

Harlequin Ducks (Histrionicus histrionicus) in Maine, 1950-1999 - Mittelhauser, Glen H.; Drury, John B.; Corr, Patrick O. (Northeastern Naturalist, 2002)
We estimate between 1,150 to 1,300 Harlequin Ducks wintered in Maine in the late 1990s. This represents over 50% of the total known wintering population in eastern North America. About 75% of these wintering birds in Maine were located in the Isle au Haut area from Vinalhaven to Swans Island. Smaller concentrations of birds were also present in eastern Hancock County (Sally Islands area) and York County (Cape Neddick area). At four groups of islands in the Isle au Haut area, numbers show a pattern of decline from 1989 to 1993 followed by increases since then. In contrast, the maximum number of birds reported each winter in York County has increased from about five birds in 1955 to about 75 birds in 1999 (rs=0.73, n=42, P<0.001). The proportion of males to females observed during mid-winter counts increased from a low of 0.8:1.0 in 1992 to a high of 1.2:1.0 in 1996 (rs=0.54, n=35, P=0.001) and averaged 1.0:1.0 (n=35, SD=3.5) from 1989-99. Given the small numbers and limited distribution of Harlequin Ducks in Maine, they should remain under full protection in the foreseeable future.
Keywords: Abundance, Distribution, and Trends; Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus

Behavior and Diving of Harlequin Ducks Wintering at Isle au Haut, Maine - Mittelhauser, Glen H.; Drury, John B.; Morrison, Eric (Waterbirds, 2008)
Mid-winter activity budgets and diving behaviors of Harlequin Ducks (Histrionicus histrionicus) at Isle an Haut, Maine were examined. Feeding was the most frequent activity and the number of hours during the day devoted to feeding increased from December to March as day length increased. Resting was not a frequent midwinter activity, but birds rested more in the morning than in the afternoon and the duration of testing bents increased in March, likely in relation to increasing day length. During foraging bouts, first-winter males had longer submergence times and longer pause times than adult males, although the resulting dive:pause ratio was similar. This may be related to feeding inefficiency of the young birds or lack of experience with local habitats or prey species. Mean dive durations and pause durations at Isle an Haut were greater than reported elsewhere for this species, and may be related to strong local currents associated with the wave washed ledges on Isle an Haut.
Keywords: Behavior; Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus

Experimental evaluation of predation of stocked salmon by riparian wildlife: effects of prey size and predator behaviours - Miyamoto, K.; Squires, T. E.; Araki, H. (MARINE AND FRESHWATER RESEARCH, 2018)
Predation after release is one of the major concerns of hatchery fish conservation and propagation. However, the relationships between the size of hatchery fish, the predator species and their behaviours in natural environments are largely unknown. To understand these relationships, we conducted predation experiments in outdoor tanks and a seminatural stream with exposure to local predators. Masu salmon (Oncorhynchus masou) of two different size classes were used as experimental prey fish in the present study. Camera trap data showed that grey herons (Ardea cinerea) were the primary predator in the experimental system, and that most herons used shallow areas in the morning or evening while feeding. Increasing the density of stocked salmon led to increases in the number of occurrences of grey heron. More importantly, predation by grey herons resulted in a significantly lower survival rate of larger salmon compared with smaller salmon. The results indicate that it is important to understand local predators, adjust the optimum body size of hatchery fish at release and choose the appropriate stocking site and time of day for maximising the effectiveness of fish stocking.
Times Cited in Web of Science Core Collection: 7 Total Times Cited: 7 Cited Reference Count: 66
Keywords: MERGUS-MERGANSER; ARDEA-CINEREA; ATLANTIC SALMON; AVIAN PREDATION; COLUMBIA RIVER; hatchery management; JUVENILE SALMONIDS; ONCORHYNCHUS-KISUTCH; PACIFIC SALMON; piscivorous water birds; predator-prey interaction; RAINBOW-TROUT; size-selective predation; WADING BIRDS

Breeding distribution, non-breeding and wintering population of the Goosander Mergus Merganser in the Odra river basin - Mizera, Tadeusz; Uhlig, Rolf; Kalisinski, Marek; Mundt, Juergen; Czeraszkiewicz, Ryszard (Vogelwelt, 1994)
Breeding Goosanders were surveyed during 1980-1993 in the Odra river basin and the population size since 1945 was analysed. The area covered comprises the rivers Oder/Odra, Neisse/Nysa Luzycka, Warta, Obra, Drawa, Gwda, Barycz, Bobr and Kwisa. The breeding population for 1980-1993 is estimated at 164-267 females with young. In addition there is a non-breeding population of some 500-600 birds. Apart from the population in Switzerland, the Odra basin contains the largest breeding population of Goosander in Central Europe. In the Odra and Warta area Goosanders mainly nest in willows Salix spec. and poplars Populus spec., while the favourite nesting trees at lakes in northwest Poland are oak Quercus spec. and beech Fagus spec. Goosanders increasingly use nest boxes for breeding. A total of 176 females with young were recorded; on average a female had 6.8 young. A new moulting ground where birds from a larger area congregate was discovered at the Bobr reservoir in southwest Poland. The overall population trend can be estimated with any degree of certainty only for the German side of the Odra, where the breeding population increased since the mid-1970s. The winter population of the Odra estuary was surveyed from boats and small airplanes. In cold winters, the area holds between 71,500 and 80,000 Goosanders, about two thirds of them on the Polish side. The Odra estuary is one of the most important wintering grounds in Europe and accounts for 47-53% of the western European wintering population of the species.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Nonbreeding Seasons; Common merganser; Mergus merganser

Clostridium botulinum Type E beurotoxin in Great Lakes fish: implications for transmission of avian botulism - Moccia, R. D.; Yule, A.; Barker, I. K.; Austin, J. (Canadian Technical Report of Fisheries and Aquatic Sciences, 2005)
Keywords: Disease; Mergus serrator; Red-breasted merganser

Cadmium contamination in wild birds as an indicator of environmental pollution - Mochizuki, Mariko; Hondo, Ryo; Kumon, Kiichi; Sasaki, Rei; Matsuba, Hironori; Ueda, Fukiko (Environmental Monitoring and Assessment, 2002)
Cadmium (Cd) is an environmental pollutant that has serious toxicity in humans and animals and causes Itai-Itai disease. However, there is little available information on its contamination in wildlife as an indicator of environmental pollution. The Cd contents in the kidney and liver of 85 wild birds from 9 different prefectures in Japan were investigated. The ranges of the Cd contents in the kidney and liver in all birds were ND-174.4 and ND-21.2 mug g-1 dry wt., respectively. The mean Cd contents were higher in the oil-contaminated birds than those in the non-contaminated ones. Furthermore, a strong correlation was obtained only between the Cd contents in the kidney and those in the liver of the oil-contaminated seabirds and not in the other non-contaminated ones. These results suggest that wild birds reflect the level of environmental contamination which should be monitored.
Keywords: Sea Ducks - General; Contaminants

Recent disastrous effects of oil pollution on birds in the San Francisco Bay region - Moffitt, James; Orr, Robert T. (California Fish and Game, 1938)
The wrecking of the oil tanker Frank H. Buck off San Francisco on March 6, 1937, proved disastrous to many spp. of aquatic birds along the coast of central California as a result of oil pollution of coastal waters. During the ensuing 2 months oil extended along about 55 miles of coast, reaching from 15 to 20 miles to sea as well as inland to a number of shallow bays. Aside from California murres, whose numbers were greatly depleted, few offshore ranging spp. were affected. In the quiet bays western grebes, white-winged scoters, ruddy ducks, eared grebes and red-throated loons suffered most in the order named. Gulls of several spp. were numerous in this area during the period of pollution but escaped disaster largely by reason of their feeding and resting habits. || ABSTRACT AUTHORS: R. T. Orr
Keywords: Melanitta fusca; Nonbreeding Seasons; White-winged Scoter; Contaminants

Parental Investment Under Predation Threat in Incubating Common Eiders (Somateria mollissima): A Hormonal Perspective - Mohring, B.; Angelier, F.; Jaatinen, K.; Parenteau, C.; Ost, M. (FRONTIERS IN ECOLOGY AND EVOLUTION, 2021)
Predation risk affects the costs and benefits of prey life-history decisions. Predation threat is often higher during reproduction, especially in conspicuous colonial breeders. Therefore, predation risk may increase the survival cost of breeding, and reduce parental investment. The impact of predation risk on avian parental investment decisions may be hormonally mediated by prolactin and corticosterone, making them ideal tools for studying the trade-offs involved. Prolactin is thought to promote parental care and commitment in birds. Corticosterone is involved in allostasis and may either mediate reduced parental investment (corticosterone-fitness hypothesis), or promote parental investment through a reallocation of resources (corticosterone-adaptation hypothesis). Here, we used these hormonal proxies of incubation commitment to examine the impact of predation risk on reproduction in common eiders (Somateria mollissima) breeding in the Baltic Sea. This eider population is subject to high but spatially and temporally variable predation pressure on adults (mainly by the white-tailed eagle Haliaeetus albicilla and introduced mammalian predators) and nests (by the adult predators and exclusive egg predators such as hooded crows Corvus cornix). We investigated baseline hormonal levels and hatching success as a function of individual quality attributes (breeding experience, female and duckling body condition), reproductive investment (clutch weight), and predation risk. We expected individuals nesting in riskier environments (i.e., on islands where predation on adults or nests is higher, or in less concealed nests) to reduce their parental investment in incubation, reflected in lower baseline prolactin levels and either higher (corticosterone-fitness hypothesis) or lower (corticosterone-adaptation hypothesis) baseline corticosterone levels. Contrary to our predictions, prolactin levels showed a positive correlation with nest predation risk. The unexpected positive relationship could result from the selective disappearance of low-quality females (presumably having low prolactin levels) from risky sites. Supporting this notion, female body condition and hatching success were positively correlated with predation risk on females, and baseline prolactin concentrations were positively correlated with duckling body condition, a proxy of maternal quality. In line with the corticosterone-adaptation hypothesis, baseline corticosterone levels increased with reproductive investment, and were negatively associated with nest predation risk. Hatching success was lower on islands where nest predation risk was higher, consistent with the idea of reduced reproductive investment under increased threat. Long-term individual-based studies are now needed to distinguish selection processes occurring at the population scale from individually plastic parental investment in relation to individual quality and variable predation risk.
Times Cited in Web of Science Core Collection: 4 Total Times Cited: 4 Cited Reference Count: 139
Keywords: CLUTCH-SIZE; BODY CONDITION; reproductive success; LONG-LIVED BIRD; BASE-LINE GLUCOCORTICOIDS; common eider (Somateria mollissima); corticosterone; CORTICOSTERONE LEVELS; FOOD AVAILABILITY; individual quality; INDIVIDUAL-DIFFERENCES; NEST-SITE SELECTION; parental care; predation risk; prolactin; STRESS-RESPONSE

FORAGING OF COMMON EIDER (SOMATERIA MOLISSIMA) WINTERING IN VELIKAYA SALMA STRAIT (KANDALAKSHA BAY, THE WHITE SEA) - Mokievsky, V. O.; Popovkina, A. B.; Poyarkov, N. D.; Tsetlin, A. B.; Zhadan, A. E.; Isachenko, A. Y. (Zoologichesky Zhurnal, 2012)
Times Cited: 0 Mokievsky, V. O. Popovkina, A. B. Poyarkov, N. D. Tsetlin, A. B. Zhadan, A. E. Isachenko, A. Yu Zhadan, Anna/J-3488-2012 0
Keywords: Nonbreeding Seasons; Trophic Interactions; Common eider; somateria mollissima

On winter foraging of the common eiders (Somateria mollissima) in the Kandalaksha Bay - Mokievsky, V. O.; Popovkina, A. B.; Poyarkov, N. D.; Tzetlin, A. B.; Zhadan, A. E. (Vogelwarte, 2003)
Keywords: Common Eider; Nonbreeding Seasons; Somateria mollissima; Trophic Interactions

Large feet are beneficial for eiders Somateria mollissima - Moller, A. P.; Laursen, K. (ECOLOGY AND EVOLUTION, 2019)
Many waterbirds have fully (totipalmate) or partially webbed (palmate) feet that are used for locomotion in aquatic environments. If webbed feet and wings both contribute to efficient diving, we predicted a positive association between the area of webbed feet and the size of the frontal locomotor apparatus (wing area, heart mass, and breast muscle, after adjusting for any partial effects of body size). We predicted that individuals able to acquire more and better quality food due to larger webbed feet should have larger livers with higher concentrations of fat-soluble antioxidants such as vitamin E, and invest more in immune function as reflected by the relative size of the uropygial gland than individuals with small webbed feet. Here, we examine if the area of webbed feet is correlated with locomotion, diet, and body condition in a sea-duck, the eider (Somateria mollissima). We analyzed an extensive database of 233 eiders shot in Danish waters and at angstrom land, Finland during winter and early spring. Eiders with larger webbed feet had a larger locomotor apparatus, but did not have larger body size, they had larger uropygial glands that waterproof the plumage, they had larger beak volume and larger gizzards, and they had higher body condition. These findings imply that eiders with large webbed feet benefitted in terms of locomotion, feeding, and reproduction.
Times Cited in Web of Science Core Collection: 2 Total Times Cited: 2 Cited Reference Count: 38
Keywords: SIZE; MASS; eider; BODY; SEA DUCK; PROPULSION; condition; duck's feet; FOOT; locomotion; PATTERN; uropygial gland; webbed feet

Function of the uropygial gland in eiders (Somateria mollissima) - Moller, A. P.; Laursen, K. (AVIAN RESEARCH, 2019)
BackgroundThe uropygial gland is an exocrine gland located above the tail of birds that produces a diverse range of biochemicals. It has been hypothesized to be involved in chemical protection, water-proofing and maintenance of plumage brightness. Although these not necessarily mutually exclusive functions have received some empirical support, there has been little empirical research on the function of water-proofing.MethodsHere we analyzed data for 229 individual eiders (Somateria mollissima) collected by Danish hunters during 20162018.ResultsThe Eider is a sea-duck that spends almost its entire life in sea water emphasizing water-proofing of the plumage. The size of the uropygial gland increased with body mass in males, but not in females, and it increased with age. The size of the uropygial gland decreased during winter. Eiders with small uropygial glands grew their feathers at a fast rate. Eiders with large wing areas had large uropygial glands.ConclusionsThese findings are consistent with large uropygial glands playing a role in water-proofing during molt and foraging, but also that uropygial glands may play a role in chemical defense.
Times Cited in Web of Science Core Collection: 5 Total Times Cited: 5 Cited Reference Count: 38
Keywords: Somateria mollissima; SIZE; Eider; INCREASES; ANAS-PLATYRHYNCHOS; Anti-microbial substance; BACTERIA; PLUMAGE; PREEN OIL; SECRETIONS; SPARROWS PASSER-DOMESTICUS; STATE; Uropygial gland; Water-proofing

Retrospectively analysing condition in historical samples of birds - Moller, A. P.; Laursen, K.; Hobson, K. A. (JOURNAL OF ZOOLOGY, 2018)
Large amounts of nitrogen are used as fertilizer across the globe annually exceeding 100 million metric tons, with consequences for primary productivity and effects at higher trophic levels. We measured N-15 values in feathers from samples of eiders Somateria mollissima wintering on the Danish coast in 2014-2016 and a century ago, using museum specimens. Blue mussels Mytilus edulis are filter feeders relying on phytoplankton as food and they constitute the main diet of eiders. Feather N-15 increased by 40% during the past century reflecting increased terrestrial runoff of N through agricultural use of fertilizer, in turn supporting increased primary production in shallow coastal systems. This increase in N-15 was associated with an increase in body mass and longer duration of moult. However, there was a recent decrease in the quality of feathers as reflected by more fault bars and a higher degree of feather wear suggesting that longer duration of moult comes at a cost in terms of poorer feather quality. These findings imply that terrestrial nitrogen subsidies to coastal marine systems from anthropogenic sources has profound effects on species such as the eider as revealed by the effects on body condition and plumage quality and hence the ability to fly and dive.
Times Cited in Web of Science Core Collection: 4 Total Times Cited: 5 Cited Reference Count: 45
Keywords: body condition; Somateria mollissima; POPULATION; IMPACTS; eider; FEATHERS; stable isotopes; DELTA-C-13; DELTA-N-15; diet; FAULT BARS; feather quality; fertilizer; METAANALYSIS; NITRATE; nitrogen-15; STABLE NITROGEN ISOTOPES; TROPHIC RELATIONSHIPS

Antibacterial and anatomical defenses in an oil contaminated, vulnerable seaduck - Moller, A. P.; Laursen, K.; Izaguirre, J.; Marzal, A. (ECOLOGY AND EVOLUTION, 2021)
Oil spills have killed thousands of birds during the last 100 years, but nonlethal effects of oil spills on birds remain poorly studied. We measured phenotype characters in 819 eiders Somateria mollissima (279 whole birds and 540 wings) of which 13.6% were oiled. We tested the hypotheses that (a) the morphology of eiders does not change due to oil contamination; (b) the anatomy of organs reflects the physiological reaction to contamination, for example, increase in metabolic demand, increase in food intake, and counteracting toxic effects of oil; (c) large locomotion apparatus that facilitates locomotion increases the risk of getting oiled; and (d) individual eiders with a higher production of secretions from the uropygial grand were more likely to have oil on their plumage. We tested whether 19 characters differed between oiled and nonoiled individuals, showing a consistent pattern. The final model retained seven predictor variables showing relationships between eiders contaminated with oil and food consumption, flight, and diving abilities. We tested whether these effects were due to differences in body condition, liver mass, empty gizzard mass, or other characters that could have been affected by impaired flight and diving ability. There was no evidence of such negative impact of oiling on eiders. We found that significant exposure to oil was associated with increased diversity of antibacterial defense. Oiled eiders did not constitute a random sample, and superior diving ability as reflected by large foot area was at a selective disadvantage during oil spills. Thus, specific characteristics predispose eiders to oiling, with an adaptation to swimming, diving, and flying being traded against the costs of oiling. In contrast, individuals with a high degree of physiological plasticity may experience an advantage because their uropygial secretions counteract the effects of oil contamination.
Times Cited in Web of Science Core Collection: 1 Total Times Cited: 1 Cited Reference Count: 61
Keywords: SEABIRDS; CLIMATE; MASS; STRESS; ducks; diving; pollution; ingestion; intestine; REHABILITATION; selection; SPILL; WATER-HORIZON OIL