Habitats of North American sea ducks - Derksen, D. V., M. R. Petersen, and J.-P. L. Savard (Studies in Avian Biology, 2015)
Breeding, molting, fall and spring staging, and wintering habitats of the sea duck tribe Mergini are described based on geographic locations and distribution in North America, geomorphology, vegetation and soil types, and freshwater and marine characteristics. The dynamics of habitats are discussed in light of natural and anthropogenic events that shape areas important to sea ducks. Strategies for sea duck habitat management are outlined and recommendations for international collaboration to preserve key terrestrial and aquatic habitats are advanced
Keywords: Conservation; Habitat

Cooperative feeding behavior in red-breasted mergansers - Des Lauriers, James R.; Brattstrom, Bayard H. (Auk, 1965)
Cooperative feeding is described for red-breasted mergansers, Mergus serrator, near Guaymas, Sonora, Mexico. Hunting birds formed a semicircle around a discovered fish and chased the fish until caught. Greater fishing success was observed in cooperative feeding than in solitary feeding. || ABSTRACT AUTHORS: Authors
Keywords: Behavior; Nonbreeding Seasons; Trophic Interactions; Mergus serrator; Red-breasted merganser

Individual optimization of reproduction in a long-lived migratory bird: a test of the condition-dependent model of laying date and clutch size - Descamps, Sebastien; Bety, Joel; Love, Oliver P.; Gilchrist, H. Grant (Functional Ecology, 2011)
P>1. Optimality theory predicts that both timing of arrival and arrival state on the breeding area will determine reproductive timing and investment in migratory organisms. We tested this idea using a condition-dependent individual optimization model (Ardea68, 1980, 225 and The American Naturalist143, 1994, 698) in common eider ducks through descriptive data, path analyses and experimental manipulation.2. Our results support the causal pathways drawn from the optimization model indicating that individuals adjust their reproductive decisions as a function of their arrival date and body condition at arrival.3. Independent of body condition, early-arriving females had a longer pre-laying period, but still initiated their nests earlier, and produced larger clutches than late-arriving birds. Independent of arrival date, females in good condition laid earlier than those in poor condition. Manipulation of pre-laying female body condition confirmed that the relationship between condition and laying date was causal.4. Female common eiders appear to optimize reproductive decisions in response to both their external (i.e. environmental conditions affecting the egg-value) and internal (i.e. body condition) states. These adjustments seem to minimize the fitness costs of reproduction, in which higher clutch size is not associated with an apparent lower survival or future breeding probability.5. Our study emphasizes the importance of (i) simultaneously considering the timing of migration, the state of individuals and the seasonal change in egg-value to understand clearly birds' breeding decisions and (ii) appreciating the potential proximate and ultimate factors explaining why some individuals delay breeding and/or produce small clutches.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Productivity; Energetics and Nutrition

Avian cholera, post-hatching survival and selection on hatch characteristics in a long-lived bird, the common eider Somateria mollisima - Descamps, Sebastien; Forbes, Mark R.; Gilchrist, H. Grant; Love, Oliver P.; Bety, Joel (Journal of Avian Biology, 2011)
Infectious diseases can have dramatic impacts on animal population dynamics, but how they influence vital rates remains understudied. We took advantage of the appearance of an avian cholera epizootic in an arctic colony of common eiders Somateria mollissima to study variation in juvenile survival and selection on hatch characteristics in relation to this highly infectious disease. Avian cholera is one of the most important infectious diseases affecting wild birds and is thought to primarily affect adult survival. Here, we show that avian cholera was associated with a 90% decline in duckling survival, leading to almost zero recruitment. Before the cholera outbreak, there was significant stabilizing selection on hatching date and significant positive directional selection on hatching mass. During cholera outbreaks, selection on hatch characteristics was no longer significant. These results were based on a low sample of surviving ducklings in cholera years, but suggested that date and mass at hatching did no longer affect duckling survival in the presence of cholera. These effects of avian cholera on post-hatching survival were likely not only the consequence of the disease per se, but also a consequence of an increase in predation rates that followed the emergence of avian cholera. Our results emphasize the dramatic direct and indirect impacts that infectious disease can have on vital rates, and thus population dynamics.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Population Dynamics; Survival; Disease

Avian Cholera, a Threat to the Viability of an Arctic Seabird Colony? - Descamps, S.; Jenouvrier, S.; Gilchrist, H. G.; Forbes, M. R. (Plos One, 2012)
Times Cited: 3 Descamps, Sebastien Jenouvrier, Stephanie Gilchrist, H. Grant Forbes, Mark R. Forbes, Mark/B-3575-2013 3
Keywords: Breeding Season; Disease; SDJV funded; Common eider; somateria mollissima

Detecting population heterogeneity in effects of North Atlantic Oscillations on seabird body condition: get into the rhythm - Descamps, Sebastien; Yoccoz, Nigel G.; Gaillard, Jean-Michel; Gilchrist, H. Grant; Erikstad, Kjell Einar; Hanssen, Sveinn Are; Cazelles, Bernard; Forbes, Mark R.; Bety, Joel (Oikos, 2010)
Climatic influences on animal populations, mediated by changes in condition-dependent survival or reproduction, have long intrigued ecologists. We analyzed links between winter North Atlantic Oscillations (NAO), a large scale climatic phenomenon affecting weather conditions over the North Atlantic and the Arctic, and average pre-laying body mass in common eiders. Body mass is a good proxy for condition-dependent reproductive output in this species. Time series links were assessed for two eider populations breeding at high latitudes, over a 10- and a 21-year time series. Winter NAO affected body mass in both populations and these effects were easier to detect when changes in the series rhythm were assessed using a novel method based on data discretization and information theory, rather than detection based on changes in amplitude, assessed using traditional linear models. Winter conditions affected body condition of eiders in both populations. Different mechanisms, however, are likely to be involved in the two populations, one being presumably affected by direct effects of climate and the other by effects through the food chain. Therefore, the same species can respond along different pathways to the same large scale climatic pattern, an important consideration when seeking to understand or manage the response of species to present and future climate change.
Keywords: Common Eider; Nonbreeding Seasons; Somateria mollissima; Energetics and Nutrition

Duckling response to changes in the trophic web of acidified lakes - Desgranges, Jean-Luc; Gagnon, Christian (Hydrobiologia, 1994)
We reared American Black Duck (Anas rubripes Brewster) and Common Goldeneye (Bucephala clangula Linnaeus) ducklings on two Quebec laurentian lakes in which we manipulated brook trout populations (Salvelinus fontinalis Mitchill), lake acidity and take productivity to relate waterfowl foraging to trophic status of lakes. We developed a preliminary model to assess the effects of lake acidity and productivity, fish predation and interspecific fish/duck competition in relation to available food (aquatic invertebrates). We then validated the model using a factorial analysis of the relationships between the variables pertaining to the diet of the fish and ducklings, and the environmental characteristics of the lakes (acidity, biological production and fish predation). The first factorial axis can be interpreted in terms of biological productivity, while the second axis illustrates the effect that fish have on the quantity and type of food available to ducklings. Two different trends appear to occur depending on whether the carrying capacity of the lake is reduced by acidification of the water or increase through liming or fertilization. In the first case, fish predation appears to have a marked effect on available food, whereas in the second case, interspecific fish/duck competition is apparently to blame for changes in the diet of ducklings. In both instances, but to a lesser extent, fish compete increasingly (exploitation and/or interference) with the ducklings, forcing them to feed to a greater extent in riparian sites that are less accessible to fish.
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Contaminants; Trophic Interactions

Effect of Lake Acidity and Morphometry on the Distribution of Aquatic Birds in Southern Quebec Canada - Desgranges, J. L.; Darveau, M. (Holarctic Ecology, 1985)
More than half the lakes in the deciduous and boreal forest regions of southern Quebec harbour at least one aquatic bird species during the nesting period. Although the number of nesting pairs per lake is generally small, those pairs are most commonly seen on lakes with a surface area of more than 15 ha, a winter pH lower than that of normal rain (i.e. < 5.6), an irregular shore configuration marked by abundant riparian vegetation, and islands. In a correspondence analysis, the first axis, representing lake acidity, explains 68% of the total variance. The common goldeneye Bucephala clangula, which is frequently seen on the most acidic lakes, and the American black duck Anas rubripes, which tends to avoid acidic lakes, show the largest contributions to that axis. The second axis describes an altitude/surface area gradient and brings the cumulative percentage of explained total variance to 94%; the great blue heron Ardea herodias and the common loon Gavia immer primarily use large, low-altitude lakes, whereas the ringnecked duck Aythya collaris and the American black duck are often found on the smaller, higher-altitude lakes. Those results are discussed as they relate to the feeding requirements of the various species of bird and the biology of their main prey. The ecological segregation of the three waterfowl species is attributed to interspecific competition.
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Trophic Interactions; Habitat

Visiting of Lakes in Southern Quebec Canada by Aquatic Birds During the Breeding Season - Desgranges, J. L.; Darveau, M. (Naturaliste Canadien (Quebec), 1988)
Five common species of aquatic birds that frequent lakes in the hilly regions of southern Ouebec are sympatrically distributed throughout the breeding season. Although their distribution was fairly uniform over both space and time, each species was observed more frequently on a specific type of lake during both nesting and brood rearing. Habitat shift vectors built from a correspondence analysis showed that the common loon (Gavia immer) and the great blue heron (Ardea herodias) were found mainly on large (i.e. > 15 ha), buffered, low altitude (i.e. < 600 m) lakes. The American black duck (Anas rubripes) and the ring-necked duck (Aythya collaris) often frequented smaller lakes with abundant riparian vegetation, while the common goldeneye (Bucephala clangula) primarily used acidic lakes. Few habitats are probably used by each species throughout the breeding season because wetlands in hilly regions are generally stable in terms of permanence of lakes and productivity of aquatic communities, so that all food and cover requirements are met on one lake type.
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Habitat

How much do small-scale changes in flight direction increase overall migration distance? - Desholm, Mark (Journal of Avian Biology, 2003)
During a radar study of autumn migrating waterfowl Denmark, individual flight trajectories of bird flocks were seen to show zigzag-like patterns, rather than exact straight lines. An analysis of these small-scale changes in flight directions, which are too small to be detected by satellite telemetry, showed that geese and common eiders Somateria m. mollissima were flying on average 0.7% and 1.6% longer distances, respectively, than if they would have flown along exact straight lines. Thus, it is concluded that the flight paths are remarkably similar to straight lines. A multivariate regression analysis suggested cross wind as a factor increasing flight distance, and hence, the small-scale changes in flight directions could in part be a result of birds trying to compensate for wind drift.
Keywords: Behavior; Common Eider; Nonbreeding Seasons; Migration; Somateria mollissima

Status of the Baltic/Wadden Sea population of the Common Eider Somateria m. mollissima - Desholm, M.; Christensen, T. K.; Scheiffarth, G.; Hario, M.; Andersson, A.; Ens, B.; Camphuysen, C. J.; Nilsson, L.; Waltho, C. M.; Lorentsen, S. H.; Kuresoo, A.; Kats, R. K. H.; et al. (Wildfowl, 2002)
A dramatic decline in the number of wintering Common Eiders from c. 800,000 to c. 370,000 occurred in Danish waters between 1990 and 2000. Denmark represents the second most important wintering area for Eiders from the Baltic/Wadden Sea flyway, and mid-winter counts suggest the total population could have fallen from c.1.2 million individuals in 1991 to c. 760,000 in 2000, implying major (c.36%) overall declines. However, although declines of similar magnitude have been detected in breeding numbers at some sites (eg Saltholm in Denmark), such a dramatic reduction is not generally evident amongst breeding numbers monitored throughout the flyway. Five hypotheses are offered to explain this discrepancy, two of which are considered likely to contribute to the differences. These relate to shortcomings in our ability to monitor adequately breeding and wintering numbers in both time and space, as well as to an unknown buffering effect of non-breeders (which are counted on the winter quarters, but which do not appear amongst assessments of breeding abundance). Parameters known to contribute to declines in population size include low duckling survival caused by viral infections, mass adult mortality due to Avian Cholera, and reduced adult annual survival rates due to mass mortality events on the wintering grounds. The population continues to be a quarry species in Denmark, Sweden, Norway and Finland. It is strongly recommended that the national monitoring schemes should be standardised and synchronised, in order to establish future population abundance and change. It is further recommended that population modelling is undertaken to understand the relationships between the numbers of Common Eiders in the Baltic/Wadden Sea flyway population and the different factors affecting their abundance.
Keywords: Abundance, Distribution, and Trends; Common Eider; Nonbreeding Seasons; Somateria mollissima

Waterfowl use of mine tailing ponds in comparison with beaver ponds in boreal eastern Canada - Desjardins, E.; Imbeau, L.; Darveau, M.; Mazerolle, M. J.; Fenton, N. J. (AVIAN CONSERVATION AND ECOLOGY, 2021)
Wetlands are essential for many animal and plant species. However, many of these ecosystems are being degraded. Wetland degradation affects the habitat of certain groups of species such as waterfowl, which use these environments at different stages of their life cycle. In this study, we assessed the quality of man-made wetlands, i.e., mine tailing ponds, in comparison to beaver ponds, which are natural wetlands used by waterfowl. We conducted repeated surveys of breeding waterfowl species present on 12 mining ponds and 38 beaver ponds in boreal western Quebec, Canada. We also conducted brood surveys and considered environmental variables at the sites that could affect their occupancy. Conditions at the mining ponds appear to be as favorable for the establishment of breeding waterfowl as those observed in beaver ponds. Using site occupancy models, we found that five out of the six species studied were as likely to occupy and breed in mining ponds as in beaver ponds: Mallard (Anas platyrhynchos), Ring-necked Duck (Aythya collaris), American Wigeon (Mareca americana), Green-winged Teal (Anas crecca), and Hooded Merganser (Lophodytes cucullatus). Both adults and broods of Common Goldeneye (Bucephala clangula) were more likely to use mining ponds than beaver ponds, but we did not find a direct relationship between goldeneye occupancy and environmental variables at our sites. Overall, the results of our study suggest that mining ponds have the potential to be managed for waterfowl and used by this group during the breeding season. However, further studies are required to assess the long-term effects of mining ponds on wildlife, particularly regarding contaminants such as heavy metals likely present at such sites.
Times Cited in Web of Science Core Collection: 1 Total Times Cited: 1 Cited Reference Count: 62
Keywords: habitat use; Common Goldeneye; waterfowl; DUCKS; ABUNDANCE; SELECTION; FISH; beaver ponds; BROODS; FOREST; GOLDENEYE; HABITAT LOSS; LAKES; mining ponds; reproduction; WETLAND USE

Pike predation affects breeding success and habitat selection of ducks - Dessborn, Lisa; Elmberg, Johan; Englund, Goran (Freshwater Biology, 2011)
P>1. Fish and ducks often belong to the same local food web, and several studies indicate that there is a general negative effect of fish on breeding ducks. This pattern has so far been addressed mainly within the framework of competition for common invertebrate prey, while predation by large fish as a force behind settlement and abundance patterns in ducks remains largely unknown. This is the first study to address the effect of fish predation on breeding ducks, isolated from that of competition, and the first experiment to explore the ability of ducks to identify and avoid lakes with high risk of fish predation.2. We used a before-after control-impact design and 11 naturally fishless lakes. Waterfowl on the lakes were surveyed during the breeding season of 2005. Large adult pike (Esox lucius) were added to two lakes in early spring 2008, and waterfowl surveys were repeated on all 11 lakes.3. Pike introduction did not affect the number of pairs on lakes during the nesting season in any of three focal duck species (mallard Anas platyrhynchos, teal Anas crecca, and goldeneye Bucephala clangula). During the brood-rearing season, however, there was a decrease in duck days in teal and goldeneye in lakes with pike, with similar trends observed in mallard. The number of goldeneye ducklings was also significantly lower in lakes with pike. We were unable to determine whether the response was attributable to direct pike predation or to broods leaving experimental lakes, but in either case, our study demonstrates high fitness costs for ducks breeding on lakes with pike.4. The apparent inability of nesting ducks to detect pike and the clear fitness implications may influence the annual recruitment of ducks on a larger scale as pike are both common and widespread. Vegetation complexity and food abundance are likely to be of overriding importance when breeding ducks are choosing a nesting site. As pike have a strong influence on breeding birds, relying on vegetation and cues of food abundance, while ignoring indicators of predation risk from fish, could lead to lakes with pike acting as an ecological trap.
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Productivity; Trophic Interactions

Combining Stable-Isotope and Body-Composition Analyses to Assess Nutrient-Allocation Strategies in Breeding White-Winged Scoters (Melanitta Fusca) - DeVink, Ean-Michel; Slattery, Stuart M.; Clark, Robert G.; Alisauskas, Ray T.; Hobson, Keith A. (Auk, 2011)
Birds meet the energy and nutrient demands of egg formation by using dietary (exogenous) sources, somatic (endogenous) nutrients, or combinations of both. Therefore, understanding plasticity in resource acquisition and the allocation strategies that are used is important for predicting how ecosystem changes across a species' range could affect vital rates. Sources of egg nutrients have traditionally been assessed through analyses of body composition, but stable-isotope analysis has provided a new tool in cases where animal tissues differ isotopically from the local food webs where they breed. We provide the first simultaneous comparison of these two techniques and test the "seasonally variable nutrient threshold hypothesis." Using body-composition analysis of White-winged Scoters (Melanitta fusca) collected at the northern extent of their range, we inferred that protein in rapidly developing ovarian follicles was derived entirely from dietary sources but that follicle lipids were most likely derived largely from somatic reserves. Stable-isotope analysis confirmed that most protein was derived from dietary sources during early (70.7-86.6%) and late (83.4-94.4%) spring collection periods, but dietary lipids were not distinguishable isotopically from stored somatic lipids to estimate lipid contributions to eggs. This pattern differed from that at the southern limit of the species' breeding range, where both lipid and protein for egg formation were derived from exogenous sources. Although our results were consistent with plasticity in resource-allocation strategies among sites (latitudinal variation), they did not support the seasonally variable nutrient threshold hypothesis within a site. We discuss the benefits of using both techniques simultaneously to assess reproductive strategies of birds that migrate between isotopically distinct areas. Received 16 March 2010, accepted 1 September 2010.
Keywords: Breeding Season; Melanitta fusca; White-winged Scoter; Energetics and Nutrition; Techniques

COMBINING STABLE-ISOTOPE AND BODY-COMPOSITION ANALYSES TO ASSESS NUTRIENT-ALLOCATION STRATEGIES IN BREEDING WHITE-WINGED SCOTERS (MELANITTA FUSCA) - DeVink, E. M.; Slattery, S. M.; Clark, R. G.; Alisauskas, R. T.; Hobson, K. A. (Auk, 2011)
Times Cited: 0 DeVink, Ean-Michel Slattery, Stuart M. Clark, Robert G. Alisauskas, Ray T. Hobson, Keith A. 0
Keywords: Breeding Season; Melanitta fusca; Techniques; white-winged Scoter; energetics and Nutrition

Is selenium affecting body condition and reproduction in boreal breeding scaup, scoters, and ring-necked ducks? - DeVink, Jean-Michel A.; Clark, Robert G.; Slattery, Stuart M.; Wayland, Mark (Environmental Pollution, 2008)
Elevated levels of selenium (Se) have been detected in wintering and spring-staging lesser scaup. Here, we compared spring scaup Se and mercury (Hg) levels to those of ring-necked ducks and white-winged scoters, species exhibiting increasing and decreasing boreal populations, respectively. Mercury concentrations were low in all three species. Geometric mean (95%Cl) liver Se concentrations were 6.2 (5.5-7.0), 4.6 (4.0-5.4), and 32.6 (28.4-37.3) mg/kg dry weight (dw) in scaup, ringnecks and scoters, respectively. Only scoter livers (66%) were above 33 mg/ka dw Se. Scaup and ringneck Se levels were unrelated to breeding status or lipid and protein levels; breeding scoters and females with greater lipid mass had higher Se than non-breeders. Egg and follicle concentrations in scaup and scoters were normal (mean [95%CI] = 2.3 [1.9-2.6] and 2.4 [2.1-2.7] mg/kg dw, respectively). Overall, we found no support for a relationship between selenium and boreal scaup and scoter declines, and discuss current Se threshold concentrations. (c) 2007 Elsevier Ltd. All rights reserved.
Keywords: Breeding Season; Melanitta fusca; White-winged Scoter; Contaminants; Productivity; Energetics and Nutrition

Effects of water salinity on growth and survival of common eider (Somateria mollissima) ducklings - DeVink, Jean-Michel A.; Gilchrist, H. Grant; Diamond, Antony W. (Auk, 2005)
The need for fresh water may affect growth and survival of young waterfowl, including ducklings of sea ducks that are routinely raised in coastal marine habitats. We studied the influence of water salinity on growth and survival of Common Eider (Somateria mollissima) ducklings collected from nests on Southampton Island, Nunavut, Canada, in July 2001 and 2002. In 2001, 50 ducklings were partitioned into five groups (n = 10) and assigned a water salinity treatment for 6.5 days. Treatments included fresh water (<1 ppt NaCl), brackish water (11 ppt or 21 ppt), seawater (33 ppt), and a mixed regime (<1 ppt for 12 h, followed by 33 ppt for six days). In 2002, the experiment was replicated twice with different ducklings. Overall, growth rates were negatively correlated, and mortality rates positively correlated, with water salinity: 3%, 17%, and 60% of ducklings died in the <1-ppt, 11-ppt, and 21-ppt treatment groups, respectively; and 100% died in the 33-ppt and mixed-regime groups. The results confirm that fresh water is required for growth and survival of Common Eider ducklings immediately after hatch, which suggests that sources of fresh water in brood-rearing areas are an important requirement for successful reproduction.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Physiology; Survival; Habitat

Increasing nest predation will be insufficient to maintain polar bear body condition in the face of sea ice loss - Dey, C. J.; Richardson, E.; McGeachy, D.; Iverson, S. A.; Gilchrist, H. G.; Semeniuk, C. A. D. (GLOBAL CHANGE BIOLOGY, 2017)
Climate change can influence interspecific interactions by differentially affecting species-specific phenology. In seasonal ice environments, there is evidence that polar bear predation of Arctic bird eggs is increasing because of earlier sea ice breakup, which forces polar bears into nearshore terrestrial environments where Arctic birds are nesting. Because polar bears can consume a large number of nests before becoming satiated, and because they can swim between island colonies, they could have dramatic influences on seabird and sea duck reproductive success. However, it is unclear whether nest foraging can provide an energetic benefit to polar bear populations, especially given the capacity of bird populations to redistribute in response to increasing predation pressure. In this study, we develop a spatially explicit agent-based model of the predator-prey relationship between polar bears and common eiders, a common and culturally important bird species for northern peoples. Our model is composed of two types of agents (polar bear agents and common eider hen agents) whose movements and decision heuristics are based on species-specific bioenergetic and behavioral ecological principles, and are influenced by historical and extrapolated sea ice conditions. Our model reproduces empirical findings that polar bear predation of bird nests is increasing and predicts an accelerating relationship between advancing ice breakup dates and the number of nests depredated. Despite increases in nest predation, our model predicts that polar bear body condition during the ice-free period will continue to decline. Finally, our model predicts that common eider nests will become more dispersed and will move closer to the mainland in response to increasing predation, possibly increasing their exposure to land-based predators and influencing the livelihood of local people that collect eider eggs and down. These results show that predatorprey interactions can have nonlinear responses to changes in climate and provides important predictions of ecological change in Arctic ecosystems.
Times Cited in Web of Science Core Collection: 25 Total Times Cited: 26 Cited Reference Count: 72
Keywords: climate change; CLIMATE-CHANGE; Arctic; PERIOD; RISK; MODELS; IMPACTS; BEHAVIOR; REPRODUCTIVE SUCCESS; agent-based model; biological interaction; ecological forecast; ENERGETIC CONTRIBUTION; foraging; individual based-model; MARITIMUS SUMMER DIETS; URSUS-MARITIMUS

Changes in the distribution of nesting Arctic seaducks are not strongly related to variation in polar bear presence - Dey, C. J.; Semeniuk, C. A. D.; Iverson, S. A.; Gilchrist, H. G. (ARCTIC SCIENCE, 2020)
Contemporary climate change is predicted to expose some species to altered predation regimes. Losses of Arctic sea ice are causing polar bears to increasingly forage on colonial seaduck eggs in lieu of ice-based hunting of marine mammals. Although polar bear predation of bird eggs has now been widely documented, it is unclear whether this change in predator behavior is having population-level consequences for Arctic breeding birds. In this study, we tested whether changes in the number of common eider nests on 76 islands in Hudson Strait, Canada, were related to variation in polar bear presence. We found that polar bear sign detected during eider breeding surveys was strongly correlated with spatial patterns of polar bears observed during aerial surveys. However, changes in eider nest count did not appear to be clearly related to polar bear sign at either the island scale or the island-cluster scale. This results of this study, therefore, suggest that the spatial overlap between eiders and polar bears varies across the landscape, but patterns of polar bear spatial variation do not seem to have driven large-scale redistribution of nesting common eiders.
Times Cited in Web of Science Core Collection: 2 Total Times Cited: 2 Cited Reference Count: 43
Keywords: BIRDS; EIDERS SOMATERIA-MOLLISSIMA; CLIMATE-CHANGE; SELECTION; SIZE; ECOLOGY; sea ice; PREDATION RISK; URSUS-MARITIMUS; FLEXIBILITY; global warming; predator-prey; SEA; seabird; Ursus

Forecasting the outcome of multiple effects of climate change on northern common eiders - Dey, C. J.; Semeniuk, C. A. D.; Iverson, S. A.; Richardson, E.; McGeachy, D.; Gilchrist, H. G. (BIOLOGICAL CONSERVATION, 2018)
Contemporary climate change has complex effects on animal populations caused by the (non-linear) combination of multiple direct and indirect effects on individuals. These interactions make predictions of the ecological response to climate change challenging; however, predictive models are required to effectively manage wildlife populations and conserve biodiversity. Here, we demonstrate how agent-based models (ABMs) can be used to predict population responses under multiple effects of climate change. We consider the case of northern common eiders (Somateria mollissima borealis), a culturally and ecologically important seaduck which is experiencing dramatic environmental change due to losses in Arctic sea ice. Our model shows that losses in Arctic sea ice will lead to increases in nest predation by polar bears in areas where these species are sympatric. However, climate mediated increases in breeding propensity and clutch size could have a large positive effect on eider population size. When considered together, these effects are predicted to result in a relatively stable eider population size over a 50-year period. Additionally, assuming eider populations are influenced by climate change in the manner proposed in this study, our model suggests that future eider populations will not be more susceptible to extrinsic perturbations (e.g. severe weather events, disease outbreaks) than were historical populations. As a result, our study demonstrates increasing climatic suitability and increasing nest predation will not lead to major changes in population size in northern common eiders, and emphasizes the importance of considering multiple, interacting effects on wildlife populations experiencing climate change.
Times Cited in Web of Science Core Collection: 12 Total Times Cited: 12 Cited Reference Count: 83
Keywords: CLUTCH SIZE; SOMATERIA-MOLLISSIMA; PATTERNS; MODELS; IMPACTS; HUMAN FOOTPRINT; POLAR BEAR POPULATIONS; PREDATION; SEA-ICE; SYSTEMS

Heavy Metals in Tissues of Waterfowl from the Chesapeake Bay USA - Di Giulio, R. T.; Scanlon, P. F. (Environmental Pollution Series A Ecological and Biological, 1984)
Concentrations of Cd, Pb, Cu and Zn were measured in 774 livers, 266 kidneys and 271 ulnar bones from 15 spp. [mallard, black duck, pintail, gadwall, American wigeon, green-winged teal, wood duck, ring-necked duck, greater scaup, bufflehead, canvasback, lesser scaup, ruddy duck, oldsquaw, white-winged scoter] of ducks obtained from the Chesapeake Bay region. A major purpose of this study was to elucidate relationships between food habits and tissue accumulations of heavy metals in Chesapeake Bay waterfowl. Liver and kidney concentrations of Cd were highest among 2 carnivorous seaduck species, Clangula hyemalis and Melanitta deglandi. Pb concentrations in tissues were generally highest in largely herbivorous species, such as Anas platyrhynchos, A. rubripes and A. strepera. Spent shot may have been an important source for tissue burdens of Pb in these ducks. No marked trends were observed between food habits and tissue concentrations of the nutrient elements, Cu and Zn.
Keywords: Melanitta fusca; Nonbreeding Seasons; White-winged Scoter; Clangula hyemalis; Long-tailed Duck; Contaminants; Bucephala albeola; Bufflehead

Bill Colour and identification of female Barrow's Goldeneye - Di Labio, Bruce; Pittaway, Ron; Burke, Peter (Ontario Birds, 1997)
Keywords: Techniques; Barrow's Goldeneye; Bucephala islandica

Decoding dumping ducks - Dickinson, Janis L. (Molecular Ecology, 2007)
Conspecific brood parasitism, where females of the same species lay eggs in each other's nests, is common in waterfowl, and is usually considered costly to host females, which are stuck looking after eggs and chicks that are not their own. However, since female waterfowl often exhibit an unusual propensity to nest near where they were born, there has been some uncertainty over whether, in ducks and geese, laying in nests of conspecifics really is parasitism. Do parasitic and host females tend to be related? And is parasitism actually a form of cooperation in disguise? In a population in Hudson Bay, Andersson & Waldeck (this issue) found that 'parasitic' eggs in nests of the common eider, Somateria mollissima sedentaria, are more closely related to host eggs than expected by chance. In fact, host and 'donor' eggs are more closely related than are females breeding at neighbouring nests. The Hudson Bay population of common eiders is unusual, because unlike in more benign climates, females do not tend to breed near their natal nest. Spatial proximity alone cannot account for the high relatedness between host eggs and 'dumped' or donor eggs. Instead, the high relatedness values are probably the result of active recognition, where females favour kin, either when dumping or accepting eggs. These new data, along with evidence indicating that the donor lays the first egg in the nest nearly half the time, suggest that what appears to be parasitism in common eiders may be a form of kin-based cooperation.
Keywords: Behavior; Breeding Season; Common Eider; Somateria mollissima

King and Common eiders of the western Canadian Arctic - Dickson, D.L. (Occasional paper - Canadian Wildlife Service, 1997)

Seasonal movement of Pacific Common Eiders breeding in Arctic Canada - Dickson, D.L. (Technical Report Series, 2012)
Pacific Common Eiders (Somateria mollissima v-nigrum) were tagged with satellite transmitters at a site in central arctic Canada and their year-round movement was tracked to determine migration routes, timing of movement, and location of moulting, wintering and staging areas. Males departed the nesting colony in the second week of July about a week after median date of start of incubation. Two thirds of the males remained in arctic Canada to moult, primarily in outer Bathurst Inlet, Dolphin and Union Strait and off Cape Parry, while the rest moulted closer to the wintering area, mostly at Kolyuchin Bay in northern Russia. Females remained on the nesting colony until time of hatch, and then moved to marine waters within 45 km of the colony to moult. Males that moulted in Canada departed on fall migration in early October, whereas females departed approximately two weeks later. Fall migration through the Beaufort and Chukchi seas took an average (± SD) of 11 ± 4 days, and none of the eiders staged until they reached the Chukotsk Peninsula in the northern Bering Sea. All but one eider wintered in the polynyas and flaw leads off the southeast coast of Chukotsk Peninsula and St. Lawrence Island; the exception likely wintered north of Nunivak Island, Alaska. Spring migration of birds destined for breeding areas in North America lasted 2.4 ± 0.7 months. Four key spring staging areas were identified: off Chukotsk Peninsula just north of the wintering area, eastern Chukchi Sea, southeast Beaufort Sea, and Lambert Channel in Dolphin and Union Strait. Eiders arrived on their breeding grounds in mid-June. All females returned to within 2 km of the nest site used the previous year (n = 7). By contrast, males were widely distributed across the breeding range in the second year from northeastern Russia to central arctic Canada. Assuming a male follows a female to her breeding area, the dispersal of males in the second breeding season suggests that Pacific Common Eiders from across eastern arctic Russia, northern Alaska and western arctic Canada are all part of the same population that winters in the northern Bering Sea. All females (n = 4), plus those males that returned to Canada to breed in the second year (n = 3), moulted within 24 km of the moult site used the previous year. However, two males that bred in Russia in the second year remained in Russia to moult, thus using an entirely different area. All wintered in the same general location in two consecutive years (n = 5). Due to their tendency to congregate in large numbers in a few select locations especially during spring migration and winter, Pacific Common Eiders are vulnerable to changes in their environment such as oil spills and altered ice conditions brought about by climate change.
Keywords: Common Eider; Molt; Migration; Somateria mollissima; Breeding season; SDJV funded; Nonbreeding season

Seasonal movement of King Eiders breeding in western Arctic Canada and northern Alaska - Dickson, D.L. (Technical Report Series, 2012)
Tracking the year-round movement of King Eiders using satellite telemetry technology has rapidly expanded our knowledge of a species that spends much of its life at sea. In this study, satellite transmitters were implanted in 86 King Eiders from two breeding sites in western arctic Canada (Victoria Island and Banks Island), as well as 10 eiders from a site in northern Alaska. Transmitters provided eider locations for a median of 13 months (range: 1-22 months). Males departed the breeding area in late June (mean ± SD: 26 June ± 6 days), whereas females departed about a month later, following hatch. Most eiders initially moved to coastal waters near the breeding area, where they staged for 2-4 weeks prior to moult migration. However, the majority of males from Victoria Island flew a distance of about 700 km to the flaw lead in the southeastern Beaufort Sea after breeding. Males arrived at moulting areas in the second week of August on average (11 August ± 9 days), whereas females arrived at the end of August (30 August ± 11 days). Regardless of the difference in timing of migration, both sexes followed the same route across the Beaufort, Chukchi, and Bering seas. Over half of the eiders (44 of 80) moulted in the northern Bering Sea off the Chukotsk Peninsula: 8 moulted off St. Lawrence Island, 2 females remained on the breeding area, 3 males moulted in the Chukchi Sea, and the rest were scattered along both the Russian and Alaskan coasts of the Bering Sea. Timing and duration of fall migration was highly variable. Some eiders (15%) did not migrate, and instead remained on the moulting area for winter. The rest departed from the moulting area over a 3-month period from 24 September to 16 December, and arrived on the wintering area over an even more protracted period from 8 October to 2 January. The area most heavily used during fall migration was the northern Bering Sea near St. Lawrence Island, where 75% of the eiders staged for 4 weeks on average (30 ± 19 days). The King Eiders spent winter in three separate regions: off the southeast Chukotsk Peninsula, off the Alaska Peninsula, and off the Kamchatka Peninsula. By the end of the first week of April, most eiders had begun spring migration. The initial move consisted of a shift northward within the winter region. This was followed by departure from the winter region, which occurred in the second half of April (23 April ± 11 days). Spring migration lasted an average of 2.4 months, and consisted of rapid long-distance movements iv followed by periods of 1-4 weeks of staging. Seven spring staging areas were identified, including the eastern Chukchi Sea and southeastern Beaufort Sea. The latter area was the most heavily used staging area for eiders destined for breeding areas in arctic Canada; the average length of stay in the southeastern Beaufort Sea was 26 ± 10 days, with peak numbers occurring from 13 May to 5 June. King Eiders arrived on the breeding grounds over a 3-week period from 6-27 June (n=30). Females showed a high degree of breeding site fidelity. Excluding a suspected immature female, average distance apart in two consecutive years was 1.6  1.1 km (n = 22). By contrast, distance between breeding sites in two consecutive years for males averaged over 1000 km (n = 22). Males and females both returned to the same general area to moult over two consecutive years; mean distance apart was 18  15 km (n = 13). Breeding and wintering areas were diffusely connected. The eiders from two separate breeding areas (Victoria and Banks islands) used all three winter regions in similar proportions. Furthermore, in the second year, males from each winter region migrated to areas throughout the breeding range. Results of this study add to the growing evidence that boundaries in the breeding area between the Pacific and Atlantic population of King Eiders are the Taymyr Peninsula in central Russia and the east side of Victoria Island in central arctic Canada (approximately 100-104° W). Six key marine areas for King Eiders were identified: the southeastern Beaufort Sea, off the west coast of Banks Island, the eastern Chukchi Sea, Bristol Bay, Bering Sea off the southeast Chukotsk Peninsula, and Anadyr Bay. Information obtained during this study will be useful in several ways, including: assessment of impact of resource development on King Eiders; development of regulations to ensure sustainable harvest; design of monitoring surveys; and identification of marine areas that require special protective status.
Keywords: Molt; Migration; Breeding season; King Eider; Somateria spectabilis; SDJV funded; Nonbreeding season

Movement of King Eiders from Breeding Grounds on Banks Island, NWT, to Moulting and Wintering Areas - Dickson, D.L. (Technical Report Series, 2012)
This study was part of a long-term program to document spatiotemporal characteristics of migration of King Eiders (Somateria spectabilis) from breeding areas in the western Canadian Arctic, and to identify key areas used by the eiders during various stages of their life history. In mid-June 2008, 16 males and 13 females were captured and implanted with satellite transmitters at Banks Island, Northwest Territories, Canada. Movements were subsequently tracked by Argos satellites. With the exception of one eider shot in July during moult migration, and another that died on a wintering area in January, the remaining 27 transmitters provided locations for a period of 13 months on average. Male King Eiders departed from the breeding grounds in late June and arrived at moulting areas to the west of the continent during the first half of August. Females departed from the breeding grounds about a month later than the males and arrived at moulting areas in the third week of August. The primary staging area for both sexes during moult migration was the west coast of Banks Island, where males and females staged an average of 25 ± 7 and 18 ± 8 days, respectively. Other areas used for staging during moult migration, but to much lesser extent, included off Cape Bathurst, NWT, and Smith Bay, Alaska, in the Beaufort Sea; off Alaska in the Chukchi Sea; and off the east side of Chukotsk Peninsula, Russia, in the Bering Sea. All but one King Eider moulted in the Bering Sea: 8 off the coast of Alaska and 19 off the coast of Russia. The remaining eider moulted in Kolyuchin Bay on the north side of Chukotsk Peninsula. All but two eiders remained in the Bering Sea for the winter: 15 off Chukotsk Peninsula, 9 along the south shore of Bristol Bay, Alaska, and 1 off Cape Olyutor, Russia. The other two eiders wintered in the North Pacific off Kodiak Island, Alaska. Eiders began to move northward as early as February 4. However, they did not depart from their wintering region until the fourth week of April on average. The eiders that migrated to breeding areas in North America staged at three locations during spring migration: off Alaska in the eastern Chukchi Sea; off Tuktoyaktuk Peninsula in the southeast Beaufort Sea and off Banks Island in the eastern Beaufort Sea. The most heavily used of these staging areas was the southeast Beaufort Sea, where all of the eiders that returned to breeding areas in North America (n=18) staged for an average of 30 ± 9 days. Peak numbers occurred in the southeast Beaufort Sea from May 8 to June 4. In the second year, all females returned to within 2.2 km of the area where they had nested the previous year (mean 1.0 ± 0.6, n=10). By contrast, males (n=11) were scattered across the breeding range from the Lena River Delta, Russia, to Victoria Island, Canada. Date of arrival of females on their nesting grounds on Banks Island in 2009 ranged from June 6 to June 17. Eiders moulted within 2 to 44 km of the site used the previous year (mean 18 ± 16 km, n=8).
Keywords: Molt; Migration; King Eider; Somateria spectabilis; SDJV funded; Nonbreeding season

Status of marine birds of the southeastern Beaufort Sea - Dickson, D. Lynne; Gilchrist, H. Grant (Arctic, 2002)
This summary and update of information on the marine birds of the southeastern Beaufort Sea is intended to support discussions on how to improve management of marine resources in the Canadian Beaufort Sea region. Perhaps the most outstanding use of the Beaufort Sea by marine birds is the staging during spring migration by hundreds of thousands of eiders and long-tailed ducks in the early open water off Cape Bathurst and Banks Island. During midsummer, tens of thousands of long-tailed ducks, scoters, scaup, and mergansers moult in the sheltered bays and behind barrier beaches and spits. Although several species of geese, ducks, loons, gulls, and terns nest on islands and in wetlands along the Beaufort Sea coast, this region has relatively few nesting seabirds compared to eastern Arctic Canada and the Bering Sea. Two possible reasons for this are a shortage of cliffs suitable for nesting and a lack of pelagic fish. The five most common sea duck species that occur in the region, long-tailed duck, king eider, common eider, surf scoter, and white-winged scoter, have all declined in numbers since the mid-1970s. Western Arctic brant populations have also declined, although their status within the Beaufort Sea region is unclear. Brant and king eider are the only marine bird species harvested there in substantial numbers. Other threats to Beaufort Sea marine bird populations include oil spills, global warming, coastal development, and contaminants. Certain threats can be managed at a local level since they are a result of local economic development, but others, such as global warming or loss of critical wintering areas, stem from environmental problems outside the region. Solving these issues will require mutual understanding and commitment on the part of numerous countries.
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons; Molt; Migration

Habitat used by common and king eiders in spring in the southeast Beaufort Sea and overlap with resource exploration - Dickson, D. L.; Smith, P. A. (Journal of Wildlife Management, 2013)
Times Cited: 0 Dickson, D. Lynne Smith, Paul A. 0
Keywords: migration; Nonbreeding Seasons; Somateria mollissima; Somateria spectabilis; SDJV funded; Common eider; habitat; King eider

Feeding Groups of Common Scoters Containing Other Species - Dickson, R. C. (British Birds, 1992)
Keywords: Black Scoter; Melanitta nigra

Phenology and duration of remigial moult in Surf Scoters (Melanitta perspicillata) and White-winged Scoters (Melanitta fusca) on the Pacific coast of North America - Dickson, R. D.; Ester, D.; Hupp, J. W.; Anderson, E. M.; Evenson, J. R.; Barrett, J. (Canadian Journal of Zoology-Revue Canadienne De Zoologie, 2012)
Times Cited: 1 Dickson, R. D. Ester, D. Hupp, J. W. Anderson, E. M. Evenson, J. R. Barrett, J. 1
Keywords: Melanitta fusca; Nonbreeding Seasons; Melanitta perspicillata; Surf Scoter; white-winged Scoter; molt

Marine mammal and seabird summer distribution and abundance in the fjords of northeast Cumberland Sound of Baffin Island, Nunavut, Canada - Diemer, Kristen M.; Conroy, Michael J.; Ferguson, Steven H.; Hauser, Donna D. W.; Grgicak-Mannion, Alice; Fisk, Aaron T. (Polar Biology, 2011)
Critical baseline population knowledge is required to properly assess the status of marine mammal and bird populations in the Canadian Arctic and the effects of climate trends on them. To address this need for one significant Arctic region, a boat-based marine mammal and seabird transect survey was conducted in Cumberland Sound fjords during summer 2008. During 173 km effort (20 h), 959 birds were recorded representing at least nine species which were dominated by Common Eiders (Somateria mollissima borealis), Iceland or Glaucous Gulls (Larus glaucoides or Larus hyperboreus), and Black Guillemots (Cepphus grylle), in addition to less common birds including Red-throated and Common Loons (Gavia stellata and Gavia immer), Northern Fulmars (Fulmarus glacialis), and Great or Lesser Black-backed Gulls (Larus marinus or Larus fuscus). Of these, 480 birds were observed on the water in one event consisting of eiders and gulls which may have biased encounter rates. Of 101 marine mammal sightings, four species were represented: 73 harp seals (Pagophilus groenlandicus), 13 beluga whales (Delphinapterus leucas), nine bowhead whales (Balaena mysticetus), five ringed seals (Pusa hispida), and one unidentified pinniped. A pod of four killer whales (Orcinus orca) was observed off-effort in Pangnirtung Fjord during the survey period. This pilot study provided the first estimates of relative abundance for marine mammals and seabirds in the study area to aid in developing future surveys.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Common Eider; Somateria mollissima

Distribution of common eiders Somateria mollissima during the brood-rearing and moulting periods in the St. Lawrence Estuary, Canada - Dieval, H.; Giroux, J. F.; Savard, J. P. L. (Wildlife Biology, 2011)
Times Cited: 0 Dieval, Helene Giroux, Jean-Francois Savard, Jean-Pierre L. 0
Keywords: Abundance, Distribution, and Trends; Nonbreeding Seasons; Common eider; somateria mollissima; molt

Impact of exposure to a simulated predator (Mergus merganser) on the activity of juvenile Atlantic salmon (Salmo salar) in a natural environment - Dionne, Melanie; Dodson, Julian J. (Canadian Journal of Zoology, 2002)
Some laboratory studies suggest that the presence of predators influences the short-term behaviour of juvenile Atlantic salmon. However, few studies have been conducted in the natural environment to confirm these observations and to document how biological and environmental factors influence the behaviour of fish faced with a predator. Of the many potential predators of juvenile Atlantic salmon, Salmo salar, the common merganser, Mergus merganser, is a major one. This study was designed to investigate the immediate and short-term impact of exposure to a simulated avian predator on the activity of juvenile Atlantic salmon in their natural habitat. The influence of riverbed sediment grain size, a major determinant of habitat choice in salmon, and body size of juvenile salmon on the nature and intensity of their response to the predator was also investigated. Observations were made before and after exposure to a model of M. merganser in three situations: (1) fry (young salmon during their first summer of life) on fine sediment, (2) fry on coarse sediment, and (3) parr (young salmon during their second or third summer of life) on coarse sediment. Observations were also made on fry exposed to a harmless floating stimulus to evaluate if the decoys were perceived as threat. Following exposure, the feeding rate of juvenile salmon decreased by 25-39% and the moving rate increased by 123-386%. Sediment grain size influenced the nature of the immediate response of juvenile salmon, while body size influenced the intensity of the moving response. Parr moved significantly more than fry after exposure to the simulated predator.
Keywords: Trophic Interactions; Common merganser; Mergus merganser

The Fitness of the Goosander Upon Leaving the Nesting Hole - Dittberner, H. (Falke, 1988)
Keywords: Breeding Season; Common merganser; Mergus merganser

Imprinting of a Velvet Scoter Melanitta-Fusca to a Female Tufted Duck Aythya-Fuligula - Dittberner, H.; Dittberner, W. (Beitraege zur Vogelkunde, 1987)
Keywords: Behavior; Melanitta fusca; White-winged Scoter

An artificial nest site for arctic nesting common eiders - Divoky, George J.; Suydam, Robert (Journal of Field Ornithology, 1995)
Artificial structures were placed on a barrier island in arctic Alaska to provide nesting cover for Common Eiders (Somateria mollissima). Wooden cross-like nest sites, providing four quadrants with 20-cm high and 61-cm long boards on two sides of each quadrant, were occupied by nesting eiders. Previous research had shown that sites based on the design developed for the eastern Atlantic subspecies (S. m. dresseri) were not used by the arctic Alaska subspecies (S. m. v-nigra) perhaps due to different predation pressures in the two regions.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Techniques

Assessing the effect of developed habitat on waterbird behaviour in an urban riparian system in Ottawa, Canada - Donaldson, Michael R.; Henein, Kringen M.; Runtz, Michael W. (Urban Ecosystems, 2007)
Waterbird species were used to assess the consequences of developed habitat on wildlife behaviour in an urban riparian system along the Rideau River in Ottawa, Canada. Fourteen developed sites and 14 undeveloped sites were surveyed from October 2004 to February 2005. Each site was approached on foot and the first observed behaviour (i.e., fleeing, foraging, resting or swimming) of each individual was recorded. A total of 10,604 behavioural observations were made across 12 taxa. Overall, the fleeing behaviour was observed more often at undeveloped sites. Foraging, resting and swimming behaviours were observed more often at developed sites. We found that seven species fled more often at undeveloped sites, including hooded merganser. This species was also more abundant at undeveloped sites, suggesting that hooded merganser may be more sensitive to anthropogenic disturbance in urban environments than other species that are habituated toward humans. For sensitive species, undeveloped shoreline may serve as a refuge from human disturbance in urban ecosystems.
Keywords: Behavior; Nonbreeding Seasons; Bucephala clangula; Common Goldeneye; Habitat; Hooded Merganser; Lophodytes cucullatus

Gull Predation and Breeding Success of Common Eiders on Stratton Island, Maine - Donehower, Christina E.; Bird, David M. (Waterbirds, 2008)
Common Eider (Somateria mollissima dresseri) breeding success and gull-eider interactions were studied at Stratton Island, Maine in 2004 and 2005. Eiders suffered little nest predation, and most egg losses to gulls were either facilitated by researcher intrusions or confined to newly inititated, unattended nest. Despite high nest success (>80%) in both study years, predation watches indicated that few, if any, ducklings survived to fledging as a result of extreme harassment and predation by Great Black-backed Gulls (Larus marinus). Gull attacks were opportunistic, involved one to 36 gulls, and often resulted in complete creche destruction. herring Gulls (L. argentatus) also took occasional young and eggs. Although Stratton Island is managed as a tern restoration site, and gull control measures to enhance tern productivity include nest destruction and shooting of tern predators, gulls continued to congregate around creching areas and to prey on ducklings. We suggest that additional gull control measures, particularly at a nearby gull colony, may enhance duckling survival. We also recommend monitoring of other eider colonies in the region to better assess duckling survival and recruitment rates.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Productivity; Trophic Interactions

Nesting Habitat Use by Common Eiders on Stratton Island, Maine - Donehower, Christina E.; Bird, David M. (Wilson Journal of Ornithology, 2009)
We examined nesting habitat use of Common Eiders (Somateria mollissima dresseri) breeding on Stratton Island. Maine in 2004 and 2005. Eiders generally avoided low-lying, open vegetation, and nested in dense, structurally complex habitats. The three most common habitat types used were Asiatic bittersweet (Celastrus orbiculata) patches, red raspberry (Rubus idaeus) thickets, and forest (primarily Malus pumila and Prunus virginiana). Nest densities were highest in bittersweet (> 500 nests/ha). Eiders had little nest predation by Larus gulls, and apparent nest success was high in all three habitats (bittersweet: 82-89%, raspberry: 87%. forest: 58-72%). Eiders appeared to select nest sites adaptively to avoid detection or access by predators, although other factors such as nest microclimate, female quality or condition, and energetic demands during incubation may also be important.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Habitat

Background-Color Acclimation of Brook Trout for Crypsis Reduces Risk of Predation by Hooded Mergansers Lophodytes-Cucullatus - Donnelly, W. A.; Whoriskey, F. G. Jr (North American Journal of Fisheries Management, 1991)
In a laboratory study, fry of brook trout Salvelinus fontinalis experienced less predation by hooded mergansers if they were previously acclimated for 11-12 weeks to tanks having the same background color as the predation arena. Color acclimation produced morphological color changes that rendered the fish more cryptic to the birds. Overall, cryptic trout accounted for 37% of predation, whereas unmatched fish experienced 63% of the total predation mortality. Implications of this study for salmonid management are that reduced predation of transplanted fish will occur if they are acclimated in hatcheries to backgrounds having similar coloration to the gravel in the habitat where they will be transplanted.
Keywords: Trophic Interactions; Hooded Merganser; Lophodytes cucullatus

Wood Duck Aix-Sponsa and Hooded Merganser Lophodytes-Cucullatus Nesting on Arrowwood National Wildlife Refuge North-Dakota USA - Doty, H. A.; Lee, F. B.; Kruse, A. D.; Matthews, J. W.; Foster, J. R.; Arnold, P. M. (Journal of Wildlife Management, 1984)
Keywords: Breeding Season; Productivity; Hooded Merganser; Lophodytes cucullatus

Differences in plumulaceous feather characters of dabbling and diving ducks - Dove, Carla J.; Agreda, Ana (Condor, 2007)
We examined variation in five microscopic plumulaceous (downy) feather characters of eighteen species of dabbling (Anatini) and diving (Aythyini, Mergini) ducks to quantify the differences between these tribes, and to explain how the plumulaceous feather ultrastructure in ducks may be influenced by different ecological requirements. Over 75% of the variation in feather characters among these ducks was explained by the first two components of a principal components analysis (PCA). Component I explained 51% of the variation and was positively correlated with the characters that quantified the number of barbules with expanded nodes and the number of expanded nodes on barbules. The microscopic feather characters of dabbling ducks (Anatini) have triangular-shaped, expanded nodes on most proximal barbules, whereas diving ducks (Aythyini and Mergini) lack expanded nodes on some barbules. Anatini also have a greater density of expanded nodes per barbule, wider nodes, shorter distance between expanded nodes, and longer barbule length. Further analysis of node density across all taxa showed that as dive depths increase, the number of expanded nodes per barbule decreases, and in the deepest divers many of the barbules completely lack expanded nodes. The significantly greater density of expanded nodes in dabbling ducks suggests that the downy nodes may function to trap more air. Diving species have fewer expanded nodes, less buoyant plumage, and are more efficient at foraging in deeper water than dabbling ducks.
Keywords: Sea Ducks - General; Physiology

Population vulnerability to climate change linked to timing of breeding in boreal ducks - Drever, M. C.; Clark, R. G.; Derksen, C.; Slattery, S. M.; Toose, P.; Nudds, T. D. (GLOBAL CHANGE BIOLOGY, 2012)
Identifying and understanding why traits make species vulnerable to changing climatic conditions remain central problems in evolutionary and applied ecology. We used spring snow cover duration as a proxy for phenological timing of wetland ecosystems, and examined how snow cover duration during spring and during the entire snow season affected population dynamics of duck species breeding in the western boreal forest of North America, 19732007. We predicted that population level responses would differ among duck species, such that late-nesting species with reduced flexibility in their timing of breeding, i.e. scaup (Aythya spp.) and scoter (Melanitta spp.), would be more strongly affected by changing snow cover conditions relative to species better able to adjust timing of breeding to seasonal phenology, i.e. mallard (Anas platyrhynchos) and American wigeon (Anas americana). Population growth rates of scaup and scoter were positively linked to spring snow cover duration; after accounting for effects of density dependence, larger populations resulted after springs with long snow cover duration than after springs with short snow cover duration. In contrast, population growth rates of mallard and wigeon were either negatively or only weakly associated with snow cover duration. Duck population models were then incorporated with snow cover duration derived from climate model simulations under the A2 emission scenario, and these predictions suggested that late-nesting duck species will experience the most severe population declines. Results are consistent with a hypothesis that the gradual climatic warming observed in the western boreal forest of North America has contributed to and may continue to exacerbate population declines of scaup and scoter.
Times Cited in Web of Science Core Collection: 54 Total Times Cited: 59 Cited Reference Count: 67
Keywords: REPRODUCTION; DYNAMICS; IMPACTS; WETLAND USE; AYTHYA-AFFINIS; DECLINING SCAUP POPULATIONS; HEMISPHERE SNOW COVER; LESSER SCAUP; TEMPERATURE; VARIABILITY

Breeding eider ducks strongly influence subarctic coastal pond chemistry - Duda, M. P.; Hargan, K. E.; Michelutti, N.; Kimpe, L. E.; Clyde, N.; Gilchrist, H. G.; Mallory, M. L.; Blais, J. M.; Smol, J. P. (AQUATIC SCIENCES, 2018)
Arctic freshwater ponds are typically pristine and oligotrophic, however seabird biovectors can markedly alter water quality via enrichment with marine-derived nutrients and bioaccumulated metals. These ornithogenic inputs can be the dominant factor structuring aquatic biota and the surrounding island flora. Here, we measured a suite of limnological water chemistry variables and sediment geochemistry from 21 freshwater ponds influenced by Common Eiders (Somateria mollissima) in Hudson Strait, near the northern communities of Cape Dorset (Nunavut) and Ivujivik (Quebec). Nest counts and sedimentary N-15 values were used as proxies of bird abundance. Nutrient-rich guano from the nesting eiders visibly promoted the growth of catchment vegetation. Elevated metal (Al, Cd, Zn), metalloid (Se), and nutrient concentrations (N, P) in the water of eider-affected sites were recorded (Sign test; p=0.004), but the proximity of many sites to the coast meant that variables related to ocean spray (conductivity, Na+, Mg2+, Cl-, Sr) confounded the effects of birds on pond water chemistry. In contrast, sediment geochemistry appeared to more clearly characterize sites according to the level of eider activity in their catchments by tracking Pb, Cd, N, and P sedimentary concentrations (Sign test; p=0.02). These results have direct implications for reconstructing historical eider population trends using sediment archives, which is necessary to inform effective conservation management strategies.
Times Cited in Web of Science Core Collection: 10 Total Times Cited: 10 Cited Reference Count: 99
Keywords: Common Eider; COMMON EIDERS; Arctic; SOMATERIA-MOLLISSIMA; STABLE-ISOTOPES; TRACE-ELEMENTS; Metals; Biovector; CAPE VERA; CHEMICAL LIMNOLOGY; DEVON ISLAND; DISSOLVED ORGANIC-CARBON; ENVIRONMENTAL-CHANGE; LEAD SHOT; Nutrients; Ornitholimnology

Hooded Merganser (Lophodytes cucullatus) - Dugger, Bruce D., Katie M. Dugger and Leigh H. Fredrickson (The Birds of North America, 2009)
Keywords: Hooded Merganser; Lophodytes cucullatus

Response of female hooded mergansers to eggs of an interspecific brood parasite - Dugger, Bruce D.; Bollmann, Lia C.; Fredrickson, Leigh H. (Auk, 1999)
Keywords: Behavior; Breeding Season; Hooded Merganser; Lophodytes cucullatus

Annual survival rates of female Hooded Mergansers and Wood Ducks in southeastern Missouri - Dugger, Katie M.; Dugger, Bruce D.; Fredrickson, Leigh H. (Wilson Bulletin, 1999)
Successful conservation and management, particularly of harvested species, relies on accurate estimates of population demographics. In addition, estimates of survival and longevity allow more accurate modeling of evolutionary life-history trade-offs within and between species. We estimated survival rates for box nesting female Hooded Mergansers (Lophodytes cucullatus) and Wood Ducks (Aix sponsa) in southeastern Missouri during 1987-1997 and 1987-1993, respectively. Hooded Merganser survival rates varied annually and ranged from 0.42-1.0 (x = 0.66 +- 0.04). Wood Duck survival did not vary significantly over time and averaged 0.63 (+- 0.02). Mean annual survival rates and capture probabilities were similar for the two species (chi2 = 0.49, df = 1, P > 0.05; chi2 = 0.02, df = 1, P > 0.05). Annual variation in Hooded Merganser survival rates was an important component of this species' population ecology, but was not related to winter weather conditions, harvest rates, b reeding season rainfall, or nesting parameters. Our female Wood Duck survival rates were higher than survival estimates for other adult females in the north-central subpopulation, but were comparable to some estimates for adult females that breed in southern and mid-Atlantic states.
Keywords: Breeding Season; Survival; Hooded Merganser; Lophodytes cucullatus

PREDATION BY HERRING-GULLS (LARUS-ARGENTATUS COUES) ON 2 ROCKY INTERTIDAL CRAB SPECIES CARCINUS-MAENAS (L) AND CANCER-IRRORATUS SAY - Dumas, J. V.; Witman, J. D. (Journal of Experimental Marine Biology and Ecology, 1993)
DUMAS, JV WITMAN, JD

Evaluating models of population process in a threatened population of Steller's eiders: a retrospective approach - Dunham, K.; Grand, J. B. (ECOSPHERE, 2017)
The Alaskan breeding population of Steller's eiders (Polysticta stelleri) was listed as threatened under the Endangered Species Act in 1997 in response to declines in abundance and a contraction in their breeding and nesting range. Aerial surveys suggest the breeding population is small and breeds in highly variable numbers, with zero birds counted in five of the last 25 years. The primary objective of this research was to evaluate competing population process models of Alaskan breeding Steller's eiders through comparison of model projections to aerial survey data. To evaluate model efficacy and estimate demographic parameters, we used a Bayesian state-space modeling framework and fit each model to counts from the annual aerial surveys using sequential importance sampling/resampling. The results strongly support that the Alaskan breeding population experiences population-level non-breeding events, and is open to exchange with the larger Russian-Pacific breeding population. Current recovery criteria for the Alaskan breeding population rely heavily on the ability to estimate population viability. Our results provide an informative model of population process that can be used to examine future population states and assess the population in terms of the current recovery and reclassification criteria.
Times Cited in Web of Science Core Collection: 4 Total Times Cited: 4 Cited Reference Count: 59
Keywords: conservation; SOMATERIA-MOLLISSIMA; SELECTION; SITE FIDELITY; REPRODUCTION; DYNAMICS; Alaska; POLYSTICTA-STELLERI; ANNUAL SURVIVAL; Bayesian; INFERENCE; sequential importance sampling; state-space models; threatened species

Assessing recovery of spectacled eiders using a Bayesian decision analysis - Dunham, K. D.; Osnas, E. E.; Frost, C. J.; Fischer, J. B.; Grand, J. B. (PLOS ONE, 2021)
Assessing species status and making classification decisions under the Endangered Species Act is a critical step towards effective species conservation. However, classification decisions are liable to two errors: i) failing to classify a species as threatened or endangered that should be classified (underprotection), or ii) classifying a species as threatened or endangered when it is not warranted (overprotection). Recent surveys indicate threatened spectacled eider populations are increasing in western Alaska, prompting the U.S. Fish and Wildlife Service to reconsider the federal listing status. There are multiple criteria set for assessing spectacled eider status, and here we focus on the abundance and decision analysis criteria. We estimated population metrics using state-space models for Alaskan breeding populations of spectacled eiders. We projected abundance over 50 years using posterior estimates of abundance and process variation to estimate the probability of quasi-extinction. The decision analysis maps the risk of quasi-extinction to the loss associated with making a misclassification error (i.e., underprotection) through a loss function. Our results indicate that the Yukon Kuskokwim Delta breeding population in western Alaska has met the recovery criteria but the Arctic Coastal Plain population in northern Alaska has not. The methods employed here provide an example of accounting for uncertainty and incorporating value judgements in such a way that the decision-makers may understand the risk of committing a misclassification error. Incorporating the abundance threshold and decision analysis in the reclassification criteria greatly increases the transparency and defensibility of the classification decision, a critical aspect for making effective decisions about species management and conservation.
Times Cited in Web of Science Core Collection: 1 Total Times Cited: 1 Cited Reference Count: 28
Keywords: DENSITY-DEPENDENCE; MODELS; VARIABILITY; CRITERIA; TIME-SERIES

Demographic responses to climate change in a threatened Arctic species - Dunham, K. D.; Tucker, A. M.; Koons, D. N.; Abebe, A.; Dobson, F. S.; Grand, J. B. (ECOLOGY AND EVOLUTION, 2021)
The Arctic is undergoing rapid and accelerating change in response to global warming, altering biodiversity patterns, and ecosystem function across the region. For Arctic endemic species, our understanding of the consequences of such change remains limited. Spectacled eiders (Somateria fischeri), a large Arctic sea duck, use remote regions in the Bering Sea, Arctic Russia, and Alaska throughout the annual cycle making it difficult to conduct comprehensive surveys or demographic studies. Listed as Threatened under the U.S. Endangered Species Act, understanding the species response to climate change is critical for effective conservation policy and planning. Here, we developed an integrated population model to describe spectacled eider population dynamics using capture-mark-recapture, breeding population survey, nest survey, and environmental data collected between 1992 and 2014. Our intent was to estimate abundance, population growth, and demographic rates, and quantify how changes in the environment influenced population dynamics. Abundance of spectacled eiders breeding in western Alaska has increased since listing in 1993 and responded more strongly to annual variation in first-year survival than adult survival or productivity. We found both adult survival and nest success were highest in years following intermediate sea ice conditions during the wintering period, and both demographic rates declined when sea ice conditions were above or below average. In recent years, sea ice extent has reached new record lows and has remained below average throughout the winter for multiple years in a row. Sea ice persistence is expected to further decline in the Bering Sea. Our results indicate spectacled eiders may be vulnerable to climate change and the increasingly variable sea ice conditions throughout their wintering range with potentially deleterious effects on population dynamics. Importantly, we identified that different demographic rates responded similarly to changes in sea ice conditions, emphasizing the need for integrated analyses to understand population dynamics.
Times Cited in Web of Science Core Collection: 3 Total Times Cited: 3 Cited Reference Count: 98
Keywords: Somateria fischeri; COMMON EIDERS; EIDERS SOMATERIA-MOLLISSIMA; POPULATION-DYNAMICS; PROTECTED AREAS; Alaska; SEA-ICE; Arctic Russia; Bering sea; BODY-MASS; BREEDING SUCCESS; full annual cycle; integrated population models; PACK ICE; spectacled eiders; YUKON-KUSKOKWIM DELTA

Energetic constraints and parental care: Is corticosterone indicative of energetic costs of incubation in a precocial bird? - DuRant, S. E.; Hopkins, W. A.; Hepp, G. R.; Romero, L. M. (Hormones and Behavior, 2013)
Times Cited: 1 DuRant, Sarah E. Hopkins, William A. Hepp, Gary R. Romero, L. Michael 1 SI
Keywords: Breeding Season; Physiology; Hooded Merganser; Lophodytes cucullatus; energetics and Nutrition

Diet of the common scoter Melanitta nigra and velvet scoter Melanitta fusca wintering in the North Sea - Durinck, Jan; Christensen, Kim Diget; Skov, Henrik; Danielsen, Finn (Ornis Fennica, 1993)
Keywords: Melanitta fusca; Nonbreeding Seasons; White-winged Scoter; Trophic Interactions; Black Scoter; Melanitta nigra

The distribution and abundance of seabirds off southwestern Greenland in autumn and winter 1988-1989 - Durinck, Jan; Falk, Knud (Polar Research, 1996)
Ship-based surveys of seabirds were carried out off southwestern Greenland in the autumn of 1988 and winter of 1989. The results provide the first quantitative information on seabird distribution and numbers for single seasons and estimates for one particular area in winter. Some oceanographic habitat characteristics important for seabird distribution are described. In winter, high numbers of king eiders Somateriaspectabilis, Brunnich's guillemots Urialomvia, glaucous gulls Larushyperboreus. Iceland gulls Larusglaucoides, great black-backed gulls Larusmarinus and black guillemots Cepphusgrylle were found in offshore habitats with heavy ice cover. An estimated 280,000 king eiders, 170,000 Brunnich's guillemots, 2,500 glaucous gulls, 7,000 Iceland gulls, 9,500 great black-backed gulls and 25,000 black guillemots were found in winter in an area west of Nuuk.
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons; King Eider

Survival of the Common Goldeneye Banded at Emma Lake Saskatchewan Canada - Duwors, M. R.; Houston, C. S.; Brown, P. W. (Journal of Field Ornithology, 1984)
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Survival

Morphometry of gut in long-tailed duck Clangula hyemalis wintering in the Polish Baltic coast - Dziala-Szczepanczyk, Ewa (Vogelwarte, 2003)
Keywords: Nonbreeding Seasons; Clangula hyemalis; Long-tailed Duck; Physiology

Morphometric characteristic of oesophagus and intestine in Black Scoter, Melanitta nigra (Anseriformes), wintering in the Polish Baltic coast - Dziala-Szczepanczyk, E. (Vestnik Zoologii, 2004)
The material for the studies was oesophagi and intestines of 52 individuals of the Black Scoter Melanitta nigra Linnaeus - 32 males (5 immature and 27 adult ones) and 20 females (11 immature and 9 adult ones). The following morphometric features of the alimentary system were analysed: oesophagus length EL and weight EW, duodenum length DL, combined length of jejunum and ileum JIL, combined length CBL and weight CBW of both caeca, small intestine length SIL, and combined length of rectum and cloaca RCL. In the analysis the sex and age of birds was taken into consideration, as well as their body sizes characterised by four parameters: body weight BW, body length BL, sternum length SL, and tarsus length TL. Despite the revealed significant dimorphic differences in the features describing the size of black scoters' bodies, only in EL, EW and RCL significant differences between males and females were recorded. No ontogenetic differences concerning black scoters' body sizes within each sex occurred. Such differences were, however, revealed both in the group of males and females with reference to EW, JIL, and CBW. A positive correlation for the relation of CBL to SIL and a negative one for the relation of EW to both parameters of caeca and to JIL, were shown.
Keywords: Nonbreeding Seasons; Physiology; Black Scoter; Melanitta nigra

Morphometric characteristic of glandular stomach and gizzard of the common scoter Melanitia nigra (aves, laridae) wintering on the polish baltic coast - Dziala-Szczepanczyk, E. (Vestnik Zoologii, 2007)
The material for studies were stomachs of 52 individuals of the Common Scoter Melanitta nigra obtained in winter in western parts of Polish Baltic coast. Six parameters of stomachs were established: glandular stomach weight (GSW) and length (GSL), gizzard length (GL) and width (GWi); combined length of both stomachs (GGL), and four measurements describing the birds' body size: body weight (BW) and length (BL), sternum length (SL) and tarsus length JL). Dimorphic differences connected with the birds' sex and age in concerning average values of stomachs parameters and indices of their relative size were examined. Relationships among values of the stomach parameters and relationships between the values of the stomach parameters and the measurements describing the bird body size were analysed. Despite clearly marked sexual dimorphism in the bird body size in favour of males, only in three parameters GWi, GW, GGL, and in the index GGL/SL (both stomach length in.relation to sternum length) drakes achieved significantly higher values than ducks. Adult and immature birds, both in the group of males and females, did not differ in body size and most average values of the stomach parameters. Only in the group of females adult individuals were characterised with heavier gizzard than immature individuals, and adult individuals of both sexes had wider gizzard than immature individuals. Except GSL and GSW, remaining parameters of the stomachs positively correlated with at least two body parameters of the birds. A positive correlation for the relation of GL to BL, TL SL; GWi to BW, BL; GW to BW, BL; GGL to BW, TL, SL were shown. No relationship between GSL and giizard measurements was noticed. But GSW was in a positive correlation with GWi and GW.
Keywords: Nonbreeding Seasons; Physiology; Black Scoter; Melanitta nigra

Morphometric characteristics of the caecum of long-tailed duck Clangula hyemalis wintering on the Polish Baltic coast - Dziala-Szczepanczyk, Ewa; Kalisinska, Elzbieta (Alauda, 2005)
Keywords: Nonbreeding Seasons; Clangula hyemalis; Long-tailed Duck; Physiology

Common Goldeneye (Bucephala clangula) - Eadie, John M., Mark L. Mallory and H. G. Lumsden (The Birds of North America, 1995)
Keywords: Bucephala clangula; Common Goldeneye

Barrow's Goldeneye (Bucephala islandica) - Eadie, John M., Jean-Pierre L. Savard and Mark L. Mallory (The Birds of North America, 2000)
Keywords: Bucephala islandica; Barrow’s Goldeneye

Density dependence, frequency dependence, and alternative nesting strategies in goldeneyes - Eadie, John M.; Fryxell, John M. (American Naturalist, 1992)
We develop a simple model to explore the conditions under which intraspecific brood parasitism would be evolutionarily stable in a cavity-nesting bird, the Barrow's golodeneye. Our results show that parasitism can be maintained by negative frequency-dependent selection, which is consistent with recent speculations. However, when we include the effects of density dependence, we find a density threshold below which frequency-dependent effects on fitness are negligible but above which frequency dependence plays a prominent role. Patterns consistent with either a mixed evolutionarily stable strategy (ESS) or a conditional ESS can therefore be obtained simply by varying population density. These results may provide an explanation for contradictory patterns found in a previous field study of blood parasitism in goldeneyes. More generally, our results indicate that conclusions about the adaptive basis of alternative reproductive behaviors can be influenced strongly by population demography. Evolutionarily stable strategy theory holds that mixed and conditional ESSs are mutually exclusive, yet we suggest that attempts to test between these alternatives in field studies may meet with limited success if population density varies.
Keywords: Behavior; Breeding Season; Barrow's Goldeneye; Bucephala islandica

Prospecting for Nest Sites by Cavity-Nesting Ducks of the Genus Bucephala - Eadie, J. M.; Gauthier, G. (Condor, 1985)
We studied the pattern of post-laying visitation of nest sites by non-nesting females in three species of cavity-nesting ducks, the Common and Barrow's goldeneyes (Bucephala clangula and B. islandica) and the Bufflehead (B. albeola). Nests were visited from mid-June to mid-July when most nesting females either had hatched their clutches or were finishing incubation. Females often visited more than one nest site and each nest site could be visited by several birds. Observations of marked individuals and body measurements of trapped birds show that most visiting females were either yearlings or failed breeders. These females always visited nest sites in intra- or inter-specific groups, and exhibited typical vocalizations and flight patterns. We propose that these females were "prospecting" for nest sites in preparation for the next breeding season. We could not find any detrimental effects of prospecting on incubating females. We also discuss the evolutionary significance of prospecting behavior and its relationship to delayed maturity and nest-site availability for both cavity- and ground-nesting North American ducks.
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye; Bucephala albeola; Bufflehead; Barrow's Goldeneye; Bucephala islandica

Cooperation, conflict, and Creching behavior in goldeneye ducks - Eadie, John M.; Lyon, Bruce E. (American Naturalist, 1998)
Creching behavior, or brood amalgamation, results in offspring being reared by adults other than their genetic parents. Although a variety of hypotheses have been proposed to explain this behavior, most assume either that brood amalgamation is accidental (i.e., nonselected) or that adoption of young is selected for because of social benefits to the young and/or adopting parents. We propose, instead, that brood amalgamation is a function of two separate processes: brood desertion and brood adoption. To examine brood desertion, we develop a graphic model to predict when parents should abandon their young and we test this model experimentally for the Barrow's goldeneye (Bucephala islandica). As predicted, females deserted their offspring when the size of the brood was experimentally reduced. Brood adoption occurred when deserted ducklings joined other broods. However, the success of ducklings in doing so was strongly dependent on the availability of potential host broods and on the age of the recipient broods. Foreign ducklings were readily accepted into young broods (<10 d old) but invariably were rejected from old broods. We could detect no benefits or costs of brood adoption to the host females, contrary to the expectations of a social benefit hypothesis. Our experiments indicate that creching behavior is driven by selection on adults to abandon their brood when the benefits of continued investment are outweighed by the reduction in future reproduction and selection on deserted ducklings to join other broods to obtain parental care. Rather than a form of cooperative brood care, creching in goldeneyes is perhaps best considered as a form of reproductive parasitism, entailing parent-offspring conflict over brood desertion and intergenerational conflict over adoption of abandoned young.
Keywords: Behavior; Breeding Season; Barrow's Goldeneye; Bucephala islandica

The relative role of relatives in conspecific brood parasitism - Eadie, J. M.; Lyon, B. E. (Molecular Ecology, 2011)
Times Cited: 2 Eadie, John McA Lyon, Bruce E. Lyon, Bruce/E-8491-2011 2
Keywords: Behavior; Breeding Season; Barrow's Goldeneye; Bucephala islandica

Common goldeneye - Eadie, J. M.; Mallory, M. L.; Lumsden, H. G. (Birds of North America, 1995)
Keywords: Breeding Season; Nonbreeding Seasons; Bucephala clangula; Common Goldeneye

Barrow's goldeneye: Bucephala islandica - Eadie, John M.; Savard, Jean-Pierre L.; Mallory, Mark L. (Birds of North America, 2000)
Keywords: Breeding Season; Nonbreeding Seasons; Barrow's Goldeneye; Bucephala islandica

Probing parentage in parasitic birds: an evaluation of methods to detect conspecific brood parasitism using goldeneyes Bucephala islandica and Bl. clangula as a test case - Eadie, John M.; Smith, James N. M.; Zadworny, David; Kuehnlein, Urs; Cheng, Kim (Journal of Avian Biology, 2010)
Conspecific brood parasitism (CBP) occurs in over 200 species of birds. Efforts to detect CBP have relied on either observational criteria, or more recently, on molecular methods. While molecular approaches are powerful, they are expensive, time consuming and may prove prohibitive for studies requiring estimates of CBP over large spatial and temporal scales involving hundreds of nests. We evaluated a series of observational methods that have been applied in previous studies to detect CBP, using two species of cavity-nesting ducks, the Barrow's goldeneye Bucephala islandica and common goldeneye B. clangula, as test species. We first describe a method based on differences in egg morphology and find it to be a reliable method to detect CBP in both species in British Columbia, Canada. The application of recursive partitioning analysis was especially effective in classifying parasitized and non-parasitized nests using differences in egg morphology. We then evaluated five additional observational criteria that have been used previously in several studies to detect CBP in birds. We show that considerable redundancy exists among all criteria, as expected, but no single method is effective at detecting all suspected cases of CBP. Subsets of criteria (2 or more eggs/d, eggs laid 2 or more days after incubation, and clutch sizes exceeding 12 eggs) were successful, in combination, in detecting 75% of parasitized nests for goldeneyes. Finally, we suggest that ecological and evolutionary analyses of the dynamics of CBP will require estimates of the frequency of the parasitic tactic in the population (rather than just the proportion of parasitized nests) and we provide a simple method to obtain such an estimate. Although our data are specific to goldeneyes, the techniques we used should have broad application to other studies of CBP.
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye; Techniques; Barrow's Goldeneye; Bucephala islandica

Breeding systems, spacing behavior, and reproductive behavior of sea ducks - Eadie, J. M. and J.-P. L. Savard (Studies in Avian Biology, 2015)
Sea ducks in tribe Mergini exhibit a wide range of spacing, breeding, and brood-rearing behaviors and have provided important insights in both theoretical and applied behavioral ecology. The strength, timing, and duration of pairing vary among species. Long-term pair bonds of more than one year are common but the proportion of birds that re-pair annually is unknown. At least two pairing periods have been documented—one in fall, likely involving birds that are reuniting, and one in spring representing new pair formation. Courtship behaviors are diverse and spectacular but their ontogeny from juveniles to adult birds has not been described. Sea ducks have one of the largest gradients in pair spacing behavior among aquatic birds, ranging from a lack of pronounced spacing in the colonial Common Eider to extremely well-developed intra- and interspecific territorial behaviors in goldeneyes and Buffleheads. Brood spacing behavior ranges from the crèching behavior of Common Eiders to the highly developed territorial system of goldeneyes. The frequency of conspecific brood parasitism (CBP) is high in species that are cavity nesting or that nest in high densities, but uncommon in species nesting at low densities in dispersed ground nests. Strong female natal and breeding philopatry results in various levels of kinship between parasites and hosts suggesting that CBP may also constitute cooperation among generations of closely related females. We review the evidence supporting various models and hypotheses attempting to explain CBP. There is increasing evidence that nest-site quality or host quality may be important factors influencing how and where females lay their eggs. Interspecific brood parasitism is found in the same species for which CBP occurs, suggesting that there may be common ecological factors that influence both behaviors. Brood amalgamation (BA) after hatch is more frequent in cavity-nesting sea ducks and ground-nesting species that nest in high densities and rare or occasional in ground-nesting species that nest at low densities. Interestingly, BA occurs more frequently in those species in which CBP is also more common. Whether BA is the result of accidental mixing or has an adaptive basis is still debated, but studies suggest differences in benefits or costs of BA among populations and years. As for CBP, kinship may also play a role in BA but evidence is equivocal. Unfortunately, we still know little about many of these species and our understanding of their social and reproductive ecology is based on detailed studies of less than half of the species in the tribe. The great behavioral diversity of ducks within the tribe Mergini offers a rich opportunity to explore the threads of physiology, ecology, and evolution that underlie a complex and intriguing spectrum of reproductive behaviors.
Keywords: Behavior; Breeding season

Mercury bioaccumulation and risk to three waterbird foraging guilds is influenced by foraging ecology and breeding stage - Eagles-Smith, Collin A.; Ackerman, Joshua T.; De La Cruz, Susan E. W.; Takekawa, John Y. (Environmental Pollution, 2009)
We evaluated mercury (Hg) in five waterbird species representing three foraging guilds in San Francisco Bay, CA. Fish-eating birds (Forster's and Caspian terns) had the highest Hg concentrations in thier tissues, but concentrations in an invertebrate-foraging shorebird (black-necked stilt) were also elevated. Foraging habitat was important for Hg exposure as illustrated by within-guild differences, where species more associated with marshes and salt ponds had higher concentrations than those more associated with open-bay and tidal mudflats. Importantly, Hg concentrations increased with time spent in the estuary. Surf scoter concentrations tripled over six months, whereas Forster's terns showed an up to 5-fold increase between estuary arrival and breeding. Breeding waterbirds were at elevated risk of Hg-induced reproductive impairment, particularly Forster's terns, in which 48% of breeding birds were at high risk due to their Hg levels. Our results highlight the importance of habitat and exposure timing, in addition to trophic position, on waterbird Hg bioaccumulation and risk. Published by Elsevier Ltd.
Keywords: Nonbreeding Seasons; Melanitta perspicillata; Surf Scoter; Contaminants

Wax Esters Secreted by the Uropygial Glands of Some Anseriformes - Edkins, E.; Hansen, I. A. (Comparative Biochemistry and Physiology B, 1976)
Wax esters of 8 Anseriformes were shown to contain simple mixtures of the following series of acids: dimethyl-haxanoic (A) and heptanoic (B): trimethyl-octanoic (C) and nonanoic (D) tetramethyl-decanoic (E) and undecanoic (F) pentamethyl-dodecanoic (G) and tridecanoic (H). E, F, G and H were obtained from the grass whistling duck [Dendrocygna eytoni], and mass spectra of G and H indicated that the methyl substituents were at positions 2, 4, 6, 8 and 10. Other Anatidae investigated were: Hawaiian goose (C, D, E) [Branta sandvicensis], European wigeon (A, B) [Anas penelope], Chiloe wigeon (A, B, C) [A. sibilatrix], redhead [Aythya americana] and harlequin [Histrionicus histrionicus] ducks (B, C, D, E) and smew (C, D,) [Mergus albellus]. The major alcohol in each species was octadecanol. The crested screamer [Chauna torquata] (family Anhimidae) had only n-acids, mainly C12 and C14 and mainly n-C14, C15 and C16 alcohols. The resemblance of these wax esters to those of the magpie goose is striking. [The relationship of the pattern of composition of the uropygial wax esters to the taxonomic position of these species is discussed.].
Keywords: Harlequin duck; Histrionicus histrionicus; Physiology

The Bottom of Lake Myvatn Iceland Past Present and Future - Einarsson, A. (Natturufraedingurinn, 1985)
The present lake came into being about 2300 years ago when the precursor lake was overrun by a lavaflow from the Threngslaborgir/Ludentsborgir crater row. Sediment from the precursor lake can be found underlying the sediment formed in the present lake, as well as mixed with scoria in pseudocraters to the south of Lake Myvatn. Palaeolimnological investigations have shown that the green alga Cladophora aegagropila increased considerably in the early 17th century. The most probable cause is a gradual decrease in water depth due to sedimentation. C. aegagrophila is a dominant macrophyte on the botton of the Syorifloi basin and serves as a substrate for invertebrates, i.a. Eurycercus lamellatus, which is important as food for diving ducks (Anatidae) and arctic char (Salvelinus alpinus). Certain bottom areas are clearly very important for wildlife conservation. These include (1) spawning sites of arctic charr and trout (Salmo trutta); (2) areas that are icefree in winter and hence important to the Barrow's goldeneye (Bucephala islandica); (3) major brood-rearing areas; (4) areas where large flocks of ducks occur regularly; (5) focal areas of common scoter (Melanitta nigra), (6) moulting sites of whooper swans (Cygnus cygnus) and (7) gadwall (Anas strepera). More research is urgently needed in order to determine how much of the sediments can be mined without harmful effects on this famous ecosystem.
Keywords: Conservation; Breeding Season; Harlequin duck; Histrionicus histrionicus; Trophic Interactions; Habitat; Black Scoter; Melanitta nigra; Barrow's Goldeneye; Bucephala islandica

Distribution and Movements of Barrow's Goldeneye Bucephala-Islandica Young in Relation to Food - Einarsson, A. (Ibis, 1988)
Barrow's Goldeneye females with broods in the Lake Myvatn district, Iceland, concentrated in a small area in the lake's outlet where the density of blackfly Simulium vittatum larvae, the principal food of the young, was highest. A downstream migration of broods took place as predicted from the growth pattern and emergence of blackflies in the river.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Dispersal; Trophic Interactions; Barrow's Goldeneye; Bucephala islandica

Settlement into Breeding Habitats by Barrow's Goldeneyes Bucephala-Islandica Evidence for Temporary Oversaturation of Preferred Habitat - Einarsson, A. (Ornis Scandinavica, 1990)
The paper describes spatio-temporal patterns of settlement into different habitats by territorial pairs of Barrow's Goldeneye at Lake Myvatn and River Laxa, Iceland, in spring. Locally, a preference for a habitat, as relfected by timing and rate of settlement and final density of pairs, could be predicted by density of potential food. Settlement followed a pattern which suggested preferred habitats were saturated. In rich habitats numbers of territorial pairs increased to a peak but decreased again before egglaying commenced. This decline could not be accounted for by a decline in food supply or redistribution of pairs due to ice break-up. This suggests that the decline represents a final adjustment of density after the habitat has become temporarily overcrowded. Territories were classified as either inshore or offshore, the latter being more costly to defend, smaller, set up later and eventually abandoned. Density of potential food was similar in both types of territory but inshore birds spent a lower proportion of time foraging.
Keywords: Behavior; Breeding Season; Habitat; Barrow's Goldeneye; Bucephala islandica

Moulting diving ducks and their food supply - Einarsson, Arni; Gardarsson, Arnthor (Aquatic Ecology, 2004)
Numbers of moulting diving ducks at Myvatn, north Iceland, were monitored over a period of 25 years; aquatic insects (Chironomidae and Simuliidae), a major food resource, were monitored with window traps for 23 years. The response of the duck populations to changes in the food situation during the moulting period varied between species. Histrionicus histrionicus and Melanitta nigra invariably go to the sea to moult. Three species (Aythya fuligula, Clangula hyemalis and Mergus serrator) have shown long term variation in moult migration habits. Aythya marila and Bucephala islandica stay for moulting, their numbers supplemented by birds from elsewhere. A. marila is a generalist feeder and therefore at low risk of starving, the strategy of Bucephala islandica is to move within the water system where the food situation tends to alternate between the lake and the river. Numbers of Bucephala islandica males moulting on Lake Myvatn were strongly and positively correlated with chironomid numbers and those moulting on the river Laxa with Simulium vittatum, the main food resource there. We did not find convincing evidence that numbers of moulting A. marila and C. hyemalis responded to variation in the food supply during the study period. This applied also to A. fuligula in the South Basin of Myvatn, but numbers in the North Basin were positively associated with chironomid numbers. M. serrator moulting on Myvatn showed negative correlations with the chironomids, perhaps reflecting a negative association between chironomids and its main food, Gasterosteus aculeatus. Apart from safety considerations for a flightless bird, the choice of a moulting site is apparently influenced by the local food conditions on one hand and by the opportunities and risks involved in migrating to distant moulting sites with an unknown food situation on the other hand.
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons; Molt

Populations of ducks and trout of the River Laxa, Iceland, in relation to variation in food resources - Einarsson, Arni; Gardarsson, Arnthor; Gislason, Gisli Mar; Gudbergsson, Gudni (Hydrobiologia, 2006)
We examined annual variation in production, recruitment and density of the three most abundant vertebrate species of the River Laxi at Lake Myvatn, Iceland: Barrow's goldeneye, Bucephala islandica, harlequin duck, Histrionicus histrionicus, and brown trout, Salmo trutta, in relation to food resources and other environmental variables. The study is largely based on correlations from long-term monitoring series in the period 1975-2002. Production of young in the harlequin duck was significantly correlated with food resources (the blackfly, Simulium vittatum) of the river, as was the recruitment of brown trout to the angling stock. In Barrow's goldeneye, which uses both the lake and the river, dispersion of adults in spring and young in August was influenced by the availability of aquatic insects in each habitat. The dispersion of Barrow's goldeneye tracks the availability of aquatic insects in each of these two main habitats. Introduced Amercian mink, Mustela vison, may have affected spring numbers and dispersion of harlequin ducks, but the evidence was not conclusive. Numbers of both duck species and the trout (as CPUE) were relatively stable, although a sharp drop in numbers followed by slow recovery was observed in Barrow's goldeneye, and an increase was observed in harlequin ducks in the first year of study.
Keywords: Breeding Season; Harlequin duck; Histrionicus histrionicus; Productivity; Population Dynamics; Trophic Interactions; Barrow's Goldeneye; Bucephala islandica

Nesting Synchrony and Clutch Size in Migratory Birds: Capital versus Income Breeding Determines Responses to Variable Spring Onset - Ejsmond, A.; Forchhammer, M.; Varpe, O.; Jonsson, J. E.; Jorgensen, C. (AMERICAN NATURALIST, 2021)
Synchronous reproduction of birds has often been explained by benefits from nesting together, but this concept fails to explain observed intraspecific variation and climate-mediated changes of breeding synchrony. Here, we present a theoretical model of birds that store resources for reproduction (capital breeders) to show how breeding synchrony, clutch size, and offspring recruitment respond to changes in timing of first possible breeding date. Our approach is based on individual fitness maximization when both prebreeding foraging and offspring development are time constrained. The model predicts less synchronous breeding, smaller clutch size, and higher chances for offspring recruitment in capital breeding birds that advance their nesting. For contrast, we also show that birds that need to acquire resources during egg laying (income breeders) do not change nesting synchrony but increase clutch size along with earlier breeding. The prediction of stronger nesting synchronization of capital breeders in years with late nesting onset is confirmed by empirical data on breeding synchrony of a high-latitude capital breeding sea duck, the common eider (Somateria mollissima). We predict that in warming high-latitude ecosystems, bird species that depend on stored reserves for reproduction are expected to desynchronize their nesting.
Times Cited in Web of Science Core Collection: 2 Total Times Cited: 2 Cited Reference Count: 65
Keywords: common eider; CLIMATE-CHANGE; BODY CONDITION; REPRODUCTION; breeding synchrony; capital breeding; clutch size; COSTS; dynamic programming; EGG SIZE; EIDERS; ENERGY; NUTRIENT; PHENOLOGY; RESERVES; timing of breeding

Declines amongst breeding Eider Somateria mollissima numbers in the Baltic/Wadden Sea flyway - Ekroos, J.; Fox, A. D.; Christensen, T. K.; Petersen, I. K.; Kilpi, M.; Jonsson, J. E.; Green, M.; Laursen, K.; Cervencl, A.; de Boer, P.; Nilsson, L.; Meissner, W.; et al. (Ornis Fennica, 2012)
Times Cited: 4 Ekroos, Johan Fox, Anthony D. Christensen, Thomas K. Petersen, Ib K. Kilpi, Mikael Jonsson, Jon E. Green, Martin Laursen, Karsten Cervencl, Anja de Boer, Peter Nilsson, Leif Meissner, Wlodzimierz Garthe, Stefan Ost, Markus Ost, Markus/C-7376-2008; Meissner, Wlodzimierz/A-3657-2008; Fox, Anthony/I-7465-2013; Christensen, Thomas/J-4915-2013; Laursen, Karsten /L-3006-2013 Meissner, Wlodzimierz/0000-0002-1259-2838; 4
Keywords: Breeding Season; Abundance, Distribution, and Trends; Nonbreeding Seasons; Common eider; somateria mollissima

Philopatric predisposition to predation-induced ecological traps: habitat-dependent mortality of breeding eiders - Ekroos, J.; Ost, M.; Karell, P.; Jaatinen, K.; Kilpi, M. (Oecologia, 2012)
Times Cited: 6 Ekroos, Johan Ost, Markus Karell, Patrik Jaatinen, Kim Kilpi, Mikael Jaatinen, Kim/A-3221-2011 6
Keywords: Breeding Season; Dispersal; Survival; Trophic Interactions; Common eider; somateria mollissima

Waterfowl counts on the Tay Estuary, 1985-1995 - Elkins, N.; Lynch, B. M. (Scottish Birds, 1997)
The Tay Estuary is an important site for both migrating and wintering waterfowl. It holds internationally important populations of wintering Eider, Redshank, and Bar-tailed Godwit. The wintering populations of Sanderling and Goldeneye achieve national importance. The estuary is a staging post for migrant waders in spring and autumn, and recent counts of migrant Sanderling, Knot, Ringed Plover and Turnstone have exceeded wintering populations, especially in spring. Mallard, Wigeon and Tufted Duck are all common wildfowl in winter, while Shelduck reach a spring peak. A substantial moulting flock of Goosander is present in late summer. This paper describes the numbers, distribution and changes in waterfowl populations on the estuary between 1985 and 1995, as shown by monthly high tide roost counts and a series of midwinter low tide counts.
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons; Molt; Common merganser; Mergus merganser

Butyltins, trace metals and morphological variables in surf scoter (Melanitta perspicillata) wintering on the south coast of British Columbia, Canada - Elliott, J. E.; Harris, M. L.; Wilson, L. K.; Smith, B. D.; Batchelor, S. P.; Maguire, J. (Environmental Pollution, 2007)
From 1998 to 2001 we examined spatial and temporal variation in uptake of contaminants by surf scoters (Melanitta perspicillata) in the Georgia Basin region of the Pacific coast of Canada. Samples were collected during late fall and early spring at industrialized and reference locations, carcasses examined, and tissues collected for histology, biomarkers, and contaminant analyses. Scoters from both Vancouver and Victoria harbours had significantly higher hepatic concentrations of Sigma butyltins than birds from a reference site. In adult mate surf scoters, hepatic Sigma butyltins increased over the winter at two sites (p = 0.02, n = 26), while mercury increased (p = 0.03, n = 15) and selenium decreased at one site p = 0.001, n = 15). Body condition decreased over the winter at both the treatment site, Howe Sound (p < 0.0001, n = 12), and the reference site, Baynes Sound (p = 0.02, n = 15). Multiple regression analysis using Akaike's Information Criteria (AIC(C)) showed an association between hepatic butyltin concentrations and overall body condition (p = 0.06, r = -0.237). Crown Copyright (c) 2006 Published by Elsevier Ltd. All rights reserved.
Keywords: Nonbreeding Seasons; Melanitta perspicillata; Surf Scoter; Contaminants; Physiology; Energetics and Nutrition

Chlorinated hydrocarbon contaminants in grebes and seaducks wintering on the coast of British Columbia, Canada: 1988-1993 - Elliott, John E.; Martin, Pamela A. (Environmental Monitoring and Assessment, 1998)
Grebe and seaduck species were collected during late winter at industrial and reference sites along coastal British Columbia, and during spring migration in the Yukon Territory, from 1988 to 1993. Liver and/or breast muscle were analyzed for polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), biphenyls (PCBs), organochlorine (OC) pesticides, and chlorophenol-related compounds. Piscivorous species, including western grebes (Aechmophorus occidentalis) and common mergansers (Mergus merganser), contained highest levels of all contaminants. DDE and PCBs were detectable in all species analyzed, but were at low levels (<50 and 100 mug/kg (sum PCBs) wet weight, respectively) in all but some grebe and merganser samples. Highest DDE concentration (229 mug/kg) was in liver of common mergansers collected at Port Alberni in 1989, and that of PCB (2300 mug/kg) in breast muscle of western grebes collected in 1992 from the same site. The interspecific PCDD/PCDF pattern was similar to that of the OC pesticides and PCBs, with the fish-eating species containing highest concentrations. The only congener detected in all samples was 2,3,7,8-TCDF, although 2,3,7,8-TCDD was regularly present. Generally, of all samples collected in 1989, those from the bleached-kraft pulp mill (BKPM) site at Port Alberni were the most contaminated with PCDDs and PCDFs. Of the chlorophenolic compounds measured, only pentachlorophenol was routinely detected, typically at levels below 5 mug/kg. Traces of 3,4,5,6-tetrachloroguaiacol, 5-chloroguaiacol and 4,5-dichloroguaiacol were also detected in a few samples, mainly from a BKPM site at Prince Rupert. By 1992, after changes to pulp mill bleaching processes and restrictions in chlorophenolic anti-sapstain use, PCDD and PCDF concentrations were substantially lower compared to 1989 in all species sampled and no longer posed a concern for human consumers. International TCDD-toxic equivalents (1-TEQs) in some western grebe samples were within the range of concentrations associated with sublethal effects in waterbird species (200-400 ng/kg).
Keywords: Nonbreeding Seasons; Contaminants; Common merganser; Mergus merganser

Comments on the distribution and migration of birds in Foxe Basin, Northwest Territories - Ellis, D. V.; Evans, J. (Canadian Field Nat, 1960)
Based on field observations by scientists and crew of the Calanus during 1955, 1956 and 1957. Bird lists and ecological notes are given principally for Igloolik Island and Frustration Bay, Rowley Island, but also for a number of other localities scattered around Foxe Basin. Dates are given for arrivals and departures of different species. King eiders, Somateria spectabilis, and snow buntings, Plectrophenax nivalis, arrived in April or May in 1956 and 1957, but most other spp. during the first 2 or 3 weeks of June. In 1957 sea-birds preceded the smaller ground birds by a few days. Signs of fall migration in 1957 were the flocking and disappearing in late July of male king eiders, followed by assembling of shore birds on beaches and along streams, the gradual disappearance of common spp., and the spasmodic appearance of non-residents. It was noticed during 1955-7, and checked with previously published reports, that spp. of sea-birds normally requiring cliff nesting-sites, e. g. fulmars, kittiwakes, and some alcids, were only casual visitors to north Foxe Basin. There are few cliffs in the area which could support colonies of these birds. || ABSTRACT AUTHORS: D. V. Ellis
Keywords: Abundance, Distribution, and Trends; Common Eider; Sea Ducks - General; King Eider

Predation by gulls on crabs in rocky intertidal and shallow subtidal zones of the Gulf of Maine - Ellis, J. C.; Chen, W.; O'Keefe, B.; Shulman, M. J.; Witman, J. D. (Journal of Experimental Marine Biology and Ecology, 2005)
Ellis, JC Chen, W O'Keefe, B Shulman, MJ Witman, JD

Regulation of intertidal food webs by avian predators on New England rocky shores - Ellis, J. C.; Shulman, M. J.; Wood, M.; Witman, J. D.; Lozyniak, S. (Ecology, 2007)
Ellis, Julie C. Shulman, Myra J. Wood, Megan Witman, Jon D. Lozyniak, Sara

Increased Bufflehead (Bucephala albeola) Breeding Activity in Minnesota - Ellis-Felege, S. N.; Skaggs, C. G.; Knutsen, G. A. (CANADIAN FIELD-NATURALIST, 2017)
Buffleheads (Bucephala albeola) predominantly nest in the boreal forests and aspen parklands of Canada and Alaska. Historically, Buffleheads were common migrants but not summer residents in Minnesota. However, recent observations in Minnesota and surrounding states suggest increased breeding activity in the region. In 1978, the first Bufflehead brood in Minnesota was recorded at East Park Wildlife Management Area. Annually, Agassiz National Wildlife Refuge (NWR) has conducted pair and brood surveys, with species-specific records available from 1990 to 2014. We report an increase in numbers of Bufflehead breeding pairs and broods at Agassiz NWR and new pair observations in surrounding areas.
Times Cited in Web of Science Core Collection: 1 Total Times Cited: 1 Cited Reference Count: 32

Longitudinal monitoring of sex steroid hormones in excrement of spectacled eiders (Somateria fischeri) - Ellsworth, A.; Buck, C. L.; Atkinson, S.; Hollmen, T. (General and Comparative Endocrinology, 2014)
From the 1970s to the 1990s, the breeding population of spectacled eiders (Somateria fischeri) in western Alaska declined by 96%, which led to the listing of this species as threatened under the Endangered Species Act in 1993. Since then, the population has stabilized, but has not recovered to pre-decline numbers. While little is known about reproductive endocrinology in spectacled eiders, in other avian species, estrogen and testosterone are known to initiate and modulate various reproductive processes including yolk protein synthesis, reproductive behaviors and secondary sex characteristics. Measurement of the metabolites of estrogen and testosterone (EM and TM, respectively) in excrement reflect circulating hormone concentrations and provide a non-invasive method to monitor reproductive physiology. We measured concentrations of excreted EM in captive females and TM in males to (1) determine the efficacy of commercially available radioimmunoassay kits to detect EM and TM, (2) describe annual profiles of EM and TM concentrations, and (3) define the reproductive season of captive spectacled eiders using endocrine status. Excrement samples were collected from captive female and male spectacled eiders three times per week throughout 1 year. Female EM and male TM levels were quantified using radioimmunoassay. Mean female EM profile exhibited values exceeding the threshold for "peak" values (EM > 193.3 ng/g) from mid-February to early July, and again in September. Additionally, the highest average concentrations of EM were seen in March, May and September. Elevated TM concentrations occurred in mid March, mid May and late June. These data suggest that levels of excreted sex steroids reflect patterns predicted by breeding landmarks in the annual cycle and will assist in field monitoring and captive breeding programs for spectacled eiders. (C) 2014 Elsevier Inc. All rights reserved.
Ellsworth, Abigail Buck, C. Loren Atkinson, Shannon Hollmen, Tuula
Keywords: Breeding Season; Somateria fischeri; Spectacled Eider; Physiology

Presence of fish affects lake use and breeding success in ducks - Elmberg, Johan; Dessborn, Lisa; Englund, Goran (Hydrobiologia, 2010)
Several previous studies indicate that presence of fish has negative effects on waterbirds breeding on lakes, owing either to competition for common invertebrate prey or fish predation on ducklings/chicks. However, others have reported results to the contrary and it remains unresolved what factors trigger, inhibit, and modulate fish-waterbird interactions. The present study was designed to test the effect of fish presence per se, with a minimum of variation in possibly confounding environmental variables. Thus, after stratifying for area, depth, altitude, pH, and total phosphorus we compared 13 lakes with and 12 without fish (mainly pike Esox lucius and perch Perca fluviatilis) with respect to (i) general species richness of waterbirds, (ii) species-specific utilization and breeding success of two dabbling ducks (mallard Anas platyrhynchos and teal Anas crecca) and a diving duck (goldeneye Bucephala clangula). General species richness of waterbirds was higher on fishless lakes. Overall use (bird days) and brood number of teal and goldeneye were higher on fishless lakes. The latter also had more benthic and free-swimming prey invertebrates compared to lakes with fish. Mallard use, mallard brood number, and abundance of emerging insects did not differ between lake groups. Generalized linear models including fish presence as factor and considering seven environmental variables as covariates, confirmed that all waterbird variables except mallard days and broods were negatively correlated to fish presence. There was also a residual positive relationship of lake area on general species richness, teal days, and teal broods. Our data demonstrate a stronger effect of fish presence on diving ducks and small surface feeding ducks than on large surface-feeding ducks. We argue that observed patterns were caused by fish predation on ducks rather than by fish-duck competition for common prey.
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Trophic Interactions; Habitat

Is the risk of nest predation heterospecifically density-dependent in precocial species belonging to different nesting guilds? - Elmberg, J.; Poysa, H. (Canadian Journal of Zoology-Revue Canadienne De Zoologie, 2011)
Times Cited: 1 Elmberg, Johan Poysa, Hannu 1
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Productivity

Evidence that Life History Characteristics of Wild Birds Influence Infection and Exposure to Influenza A Viruses - Ely, C. R.; Hall, J. S.; Schmutz, J. A.; Pearce, J. M.; Terenzi, J.; Sedinger, J. S.; Ip, H. S. (Plos One, 2013)
Times Cited: 0 Ely, Craig R. Hall, Jeffrey S. Schmutz, Joel A. Pearce, John M. Terenzi, John Sedinger, James S. Ip, Hon S. 0
Keywords: Disease; Sea ducks

Predation by Fish and Common Mergansers on Darters Pisces Percidae in the Thames River Watershed of Southwestern Ontario Canada - Englert, J.; Seghers, B. H. (Canadian Field-Naturalist, 1983)
Keywords: Trophic Interactions; Common merganser; Mergus merganser

Plastic and metal ingestion in three species of coastal waterfowl wintering in Atlantic Canada - English, M. D.; Robertson, G. J.; Avery-Gomm, S.; Pine-Hay, D.; Roul, S.; Ryan, P. C.; Wilhelm, S. I.; Mallory, M. L. (Marine Pollution Bulletin, 2015)
Relatively little attention has been paid to the occurrence of anthropogenic debris found in coastal species, especially waterfowl. We examined the incidence of ingested plastic and metal in three waterfowl species wintering in Atlantic Canada: American black ducks (Anas rubripes) and mallards (A. platyrhynchos), two species that use marine and freshwater coastal habitats for foraging in the winter, and common eider (Somateria mollissima), a coastal marine species that feeds on intertidal and subtidal benthic organisms. Plastic was found in the stomachs of 46.1% (6/13) of mallards and 6.9% (6/87) of black ducks, the first report of ingested anthropogenic debris in these species, while 2.1% (1/48) of eider stomachs contained plastic. Metal was found in the stomachs of 30.8% (4/13) of mallards, 2.3% (2/87) of black ducks, and in 2.1% (1/48) of eiders. Our results indicate that species using coastal marine and freshwater environments are exposed to and ingest anthropogenic debris. (C) 2015 Elsevier Ltd. All rights reserved.
English, Matthew D. Robertson, Gregory J. Avery-Gomm, Stephanie Pine-Hay, Donald Roul, Sheena Ryan, Pierre C. Wilhelm, Sabina I. Mallory, Mark L.
Keywords: Common Eider; Contaminants; Somateria mollissima; Nonbreeding season

Influence of fish assemblage and shallow lake productivity on waterfowl communities in the Boreal Transition Zone of western Canada - Epners, C. A.; Bayley, S. E.; Thompson, J. E.; Tonn, W. M. (Freshwater Biology, 2010)
P>1. Shallow lakes in the Boreal Transition Zone (BTZ) in Alberta, Canada are naturally productive systems that provide important breeding and moulting habitat for many waterfowl (Anseriformes). To examine the relative importance of biotic and abiotic factors on waterfowl population densities, species richness and community composition, we surveyed 30 shallow lakes and evaluated the relationships among fish communities, lake characteristics and waterfowl in both breeding and moulting habitat. Shallow lakes were either fishless (n = 15), contained only small-bodied fishes (n = 10) or contained large-bodied, mostly predatory, fish in addition to small-bodied fish (n = 5).2. Environmental factors, including water colour, submerged aquatic vegetation, lake area and potassium, explained 24.3% of the variation in breeding waterfowl communities. Fish assemblage contributed independently to a small but significant proportion (13.4%) of the variation, while 13.8% of the explained variation was shared between environmental factors and fish assemblage. In total, 51.5% of the variation in breeding waterfowl communities was explained.3. Overall, 55.5% of the total variation in moulting waterfowl communities was explained. Environment alone [especially total phosphorus, lake area, maximum depth and dissolved organic carbon (DOC)] and variation shared by fish and environment similarly accounted for most of the explained variation in moulting waterfowl communities (21.7% and 25.7% respectively), while fish assemblage was only one-third as important (8.1%).4. Both breeding and moulting waterfowl densities increased with lake productivity, even in eutrophic and hypereutrophic lakes. Breeding waterfowl density was also twice as great in fishless lakes than in lakes with fish, after accounting for lake area.5. Certain waterfowl taxa were linked to fishless lakes, especially in the moulting season. Canvasback and moulting ring-necked ducks were linked to small-bodied fish lakes, whereas moulting common goldeneye were indicators of large-bodied fish lakes. Knowledge of fish presence and species composition can therefore help guide conservation and management of waterfowl habitat in western Canada. Our results suggest that management efforts to maintain the most productive waterfowl habitat in the BTZ should focus on smaller, shallow, fishless lakes, particularly given that larger fish-bearing systems have greater regulatory protection.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Nonbreeding Seasons; Bucephala clangula; Common Goldeneye; Habitat

Oil pollution and migratory birds - Erickson, Ray C. (Atlantic Nat, 1963)
Since most birds suffering from oil pollution die at sea, observed loss is minimal. Aquatic species are most affected loons, greater scaup, eiders, scoters, oldsquaws, American golden-eyes, murres and auks. Feeding is impaired with buoyancy loss, with difficulty in flying and destruction of food. This results in inability to maintain body temperature and mortality is hastened with cold environmental temperatures. Treatment consists of a fuller's earth shampoo preceded when necessary by application of butter, soapy warm bath and over-night drying. || ABSTRACT AUTHORS: E. M. Boyd
Keywords: Sea Ducks - General; Contaminants

Breeding Performance of the Goosander Mergus-Merganser in the Archipelago of the Gulf of Finland - Eriksson, K.; Niittyla, J. (Ornis Fennica, 1985)
The clutch size of the Goosander Mergus merganser was studied in the archipelago of the Gulf of Finland, during the years 1973-81. The average clutch size was 9.93 .+-. 1.69 (SD; N = 231). The annual averages did not differ significantly but the females which started to nest earliest in the spring laid larger clutches than the late starters. Goosanders started to nest on the average on 27 April, but in an early spring the first eggs were found at the end of March. Altogether 75 females were recaptured at least once. The relative age of the female showed a positive correlation with clutch size, and a negative one with the laying date, which indicates that old females lay large clutches early in the season. The average weight of the incubating female was 1196 .+-. 73 grams (N = 156), and there was a positive correlation between the average egg size and the weight of the female. The average hatching success was 91% (N = 199), clutches laid in the beginning of May being the most successful. The most experienced females produced the highest number of young per clutch.
Keywords: Breeding Season; Productivity; Common merganser; Mergus merganser

Competition between Fresh Water Fish and Goldeneyes Bucephala-Clangula for Common Prey - Eriksson, M. O. G. (Oecologia (Berlin), 1979)
Goldeneyes preferred lakes [in Sweden] without fish to those with fish. Field experiments were conducted to investigate whether or not this preference could be ascribed to a higher food supply in the lakes devoid of fish, as goldeneyes and some freshwater fish (perch [Perca fluviatilis] and roach [Leuciscus rutilis] in the studied lakes) to some extent feed on the same kinds of prey. Changes in the abundance of prey common to fish and goldeneyes and the use by goldeneyes of lakes after experimentally changed predation pressure from fish were studied. Some aquatic insect groups, (Cloeon larvae, Odonata larvae, water bugs, dytiscids and Chaoborus larvae) proved sensitive to predation from fish. Goldeneyes increased their use of an experimental lake after fish were removed; they used this lake more than an adjacent control lake. Fish may be able to reduce the availability of foods common to the goldeneyes to such an extent that the selection by the ducks of feeding localities is affected and exploitation competition between freshwater fish and goldeneyes may occur.
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Trophic Interactions

Acidification of Lakes Effects on Waterbirds in Sweden - Eriksson, M. O. G. (Ambio, 1984)
The decline in abundance of fish in acidified lakes affects the bird fauna according to the feeding habits of the species in question. Ducks feeding on aquatic insects are favored by the reduced competition with fish for common prey. Goldeneye in particular exploit the increased populations of highly mobile insects which turn up in lakes with reduced densities of fish. Among fish-eating birds such as divers and mergansers, which search for prey while swimming with their eyes below the surface, there is a compensation for the reduced abundance of fish prey by a concomitant increase in water transparency which makes remaining fish easier to detect. Other species, such as osprey and terns, do not benefit from the increased visibility as their diving depths limit them to fish in the uppermost meter of water. In addition to exposure to ecological changes resulting from acidification, birds are also increasingly exposed to metal pollutants, which increase in acidified waters. Among passerine birds, impaired reproductive success has been related to breeding in territories close to the shore where they are exposed to Al by feeding on emerging insects. Generally, the waterbird fauna in the type of lake which is susceptible to acidification is comparatively sparse. But for some species, such as divers and osprey, a considerable proportion of the total European populations breed at such waters and it is of international importance for the preservation of these species that people are concerned with the effects of lake acidification.
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Contaminants; Trophic Interactions; Common merganser; Mergus merganser; Habitat

Parental investment and adult survival in Norwegian seabirds - Erikstad, K. E.; Anker-Nilssen, T.; Asheim, M.; Barrett, R. T.; Bustnes, J. O.; Jacobsen, K. O.; Johnsen, I.; Saether, B. E.; Tveraa, T. (NINA (Norsk Institutt for Naturforskning) Forskningsrapport, 1994)
Parental investment and adult survival was studied in Puffins Fratercula arctica (Hornoya and Rost), Common Guillemots Uria aalge (Hornoya), Brunnich's Guillemots Uria lomiva (Hornoya), Kittiwake Rissa tridacytla (Hornoya), and Common Eider Somateria mollissima (Grindoya). The survival of birds was estimated using the computer programme SURGE. Survival of Puffins on Rost was estimated to 91% and on Hornoya to only 79% during the same time period. Such a considerable difference in survival rate implies that birds on Rost have a further life expectancy of 7 years from first breeding, while the corresponding estimate for birds from Hornoya is only 3 years. For most of the species for which data from several years were available, annual adult survival varied considerably: for Common Guillemots and Kittiwakes on Hornoya from 87% to 100% and from 60% to 91%, respectively, and for Common Eiders on Grindoya from 60% to 100%. Experimental manipulation of clutch size in Kittiwakes showed that females produce the number of eggs which maximize the number of fledglings. Females which raised an additional chick had a considerably lower survival than controls. Studies on both Puffins and Common Eiders showed that female body condition greatly influenced her willingness to invest in offsprings. To increase our understanding of population regulation in seabirds there is a great need for long-term studies in combination with experimental manipulation to examine the relationship between food shortage, body condition and adult survival.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Productivity; Survival

Clutch size determination in common eiders: An egg removal and egg addition experiment - Erikstad, Kjell Einar; Bustnes, Jan O. (Journal of Avian Biology, 1994)
Egg addition and egg removal experiments in Common Eiders Somateria mollissima were carried out during three breeding seasons to examine their effect on final clutch size. When the third egg and all subsequent eggs were removed during the laying cycle, females did not respond by laying more eggs. This result is consistent with the hypothesis that egg-production is limited by body reserves; however the experiment may have been carried out too late in the laying cycle to make further egg-laying possible. When three eggs were added to nests containing two eggs females produced fewer eggs than a normal clutch. This suggests that females respond to egg parasitism by reducing their own clutch size. A reduced host clutch size suggests that availability of body reserves is not the only control of clutch size in Eiders, but that costs to incubate and/or to care for chicks may increase with increasing clutch size.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Productivity

Clutch-size determination in precocial birds: A study of the common eider - Erikstad, Kjell Einar; Bustnes, Jan Ove; Moum, Truls (Auk, 1993)
Clutch-size determination in the Common Eider (Somateria mollissima) was evaluated in a colony in northern Norway. Females in good body condition (determined from mass at hatching) produced large clutches and had a shorter incubation period than females with small body reserves. Females in good body condition cared for young (including adoption of the young of other females), while females in poor body condition abandoned their young soon after hatching. Repeatability (an upper limit to heritability) of clutch size, which for individual females varies from three to six eggs, does not differ significantly from zero. A hypothesis is proposed, suggesting that there is a trade-off involved in allocating body reserves to eggs, incubation, and care of chicks and that females use a particular clutch-size strategy related to their body condition and ability to care for young.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Productivity

Does the cost of incubation set limits to clutch size in common eiders Somateria mollissima? - Erikstad, Kjell Einar; Tveraa, Torkild (Oecologia (Berlin), 1995)
We examined the effect of natural clutch size on the cost of incubation in a population of common eiders Somateria mollissima nesting in Tromso, northern Norway. The body condition of females at day 5 in the incubation period was not related to clutch size (3-6 eggs), but females incubating large clutches lost more mass and had a lower body condition at day 20 in the incubation period than females incubating small clutches. Females incubating large clutches had a slightly shorter incubation period and a lower egg predation rate. The results do not support the hypothesis that the female's ability to produce eggs is the only ultimate control of clutch size in eider. Instead the results suggest that body there may be an interaction between the allocation of body reserves to eggs and incubation, and that females producing large clutches allocate more of their body reserves to incubation than females producing small clutches, in order to shorten the incubation period and to minimise the risk of predation on eggs.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Energetics and Nutrition

Significance in intraclutch egg-size variation in Common Eider: The role of egg size and quality of ducklings - Erikstad, Kjell Einar; Tveraa, Torkild; Bustnes, Jan Ove (Journal of Avian Biology, 1998)
In ducks and geese intraclutch egg-size variation shows a consistent pattern. The first egg is generally smaller than the second egg and from then on egg size declines over the laying sequence. Such an intraclutch egg-size pattern has previously been described in the Common Eider Somateria mollissima. In our study area the differences between the largest and the smallest egg in a clutch increased on average from 7.5% among 3-egg clutches to 14.2% among 6-egg clutches. The maximum difference was as much as 25% among 6-egg clutches. In the present study we examine the relationship between egg size, laying position and the growth of ducklings. We have done this by collecting complete clutches of which we knew the exact laying order and the size of all eggs, and transferred them to a standard incubator to hatch. We then fed ducklings ad lib and measured their growth rate in relation to egg size and laying order. There was a close relationship (r2 = 0.82) between egg size and hatching body mass of ducklings. Large eggs in a clutch also produced relatively larger ducklings (in relation to egg size) at hatching than smaller eggs. Ducklings from large second eggs in a clutch had a higher body mass up to day 12 after hatching than ducklings from small final eggs. The results are consistent with the hypothesis that female eiders allocate resources to eggs in their clutch differentially and that such an investment may affect growth rate and hence the chances of survival of the ducklings.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Productivity; Physiology

A joint clutch of Barrow's goldeneye and bufflehead eggs - Erskine, Anthony J. (Canadian Field Nat, 1959)
A nest was found in British Columbia containing eggs of Bucephala islandica and B albeola. Young of both species hatched and left the nest successfully. || ABSTRACT AUTHORS: A. J. Erskine
Keywords: Behavior; Breeding Season; Bucephala albeola; Bufflehead; Barrow's Goldeneye; Bucephala islandica

Further notes on interspecific competition among hole-nesting ducks - Erskine, Anthony J. (Canadian Field Nat, 1960)
In 1959 a Barrow's goldeneye (Bucephala islandica) nest in British Columbia, described earlier (Can. Field Nat., 73131. 1959), contained a recently dead female bufflehead B. albeola, probably killed by the goldeneye found in the nest. Natural nest-sites for goldeneye are few and nest-boxes are accepted. In 1959, one box contained a joint clutch of Barrow's goldeneye and bufflehead eggs, incubated successfully by the latter species. This is the only record of such a joint clutch incubated by bufflehead. || ABSTRACT AUTHORS: A. J. Erskine
Keywords: Behavior; Breeding Season; Bucephala albeola; Bufflehead; Barrow's Goldeneye; Bucephala islandica

Nest-site tenacity and homing in the bufflehead - Erskine, Anthony J. (Auk, 1961)
Female buffleheads Bucephala albeola exhibit a tendency to home to their natal lake, often returning to the nest site used in previous years. Re-use of a nest site may be prevented by its having become unusable, or disturbance during the previous nesting season may induce a move to another site. The homing tendency and the distance of moves between nests are similar to those established earlier for other species of ducks. Female buffleheads also tend to return to molting areas, while both sexes return to wintering grounds used in previous years. Evidence is presented to suggest that male bufflehead may home to the breeding grounds, often independently of the female. Banding male ducks on their territories, lacking for the bufflehead and for other ducks seems the logical way to prove homing in drakes. || ABSTRACT AUTHORS: A. J. Erskine
Keywords: Breeding Season; Dispersal; Bucephala albeola; Bufflehead

Nest-site competition between bufflehead Bucephala-albeola , mountain bluebird Sialia-currucoides and tree swallow lridoprocne-bicolorl - Erskine, A. J. (Can Field Natur, 1964)
Keywords: Breeding Season; Habitat; Bucephala albeola; Bufflehead

Parental Carrying of Young by Goosanders - Erskine, A. J. (Wildfowl, 1971)
Keywords: Behavior; Common merganser; Mergus merganser

Growth and Annual Cycles in Weights Plumages and Reproductive Organs of Goosanders in Eastern Canada - Erskine, A. J. (Ibis, 1971)
Keywords: Physiology; Energetics and Nutrition; Common merganser; Mergus merganser

Durability of Tree Holes Used by Buffleheads - Erskine, A. J. (Canadian Field-Naturalist, 1978)
Keywords: Breeding Season; Habitat; Bucephala albeola; Bufflehead

Joint Laying in Bucephala Ducks Parasitism or Nest-Site Competition - Erskine, A. J. (Ornis Scandinavica, 1990)
The assumption that parasitism is involved in most joint laying by two or more conspecific ducks in one nest is questioned. Joint laying by Buffleheads Bucephala albeola and Barrow's Goldeneyes B. islandica can be explained by assuming that all females start laying with the intent to incubate. When two or more birds lay in the same nest, one bird incubates the joint clutch; birds excluded once and continuing to lay may incubate a partial clutch, or another joint clutch, or be excluded again. Birds that have been excluded from incubation twice may "dump" one or two eggs that they cannot resorb, as a last resort. The relative costs and benefits of various scenarios are reviewed.
Keywords: Behavior; Breeding Season; Bucephala albeola; Bufflehead; Barrow's Goldeneye; Bucephala islandica

Status and Movements of Common Eiders in the Maritime Provinces Canada - Erskine, A. J.; Smith, A. D. (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: Abundance, Distribution, and Trends; Common Eider; Somateria mollissima

Surface elevation dynamics in vegetated Spartina marshes versus unvegetated tidal ponds along the mid-Atlantic coast, USA, with implications to waterbirds - Erwin, R. Michael; Cahoon, Donald R.; Prosser, Diann J.; Sanders, Geoffrey M.; Hensel, Philippe (Estuaries and Coasts, 2006)
Mid Atlantic coastal salt marshes contain a matrix of vegetation diversified by tidal pools, pannes, and creeks, providing habitats of varying importance to many species of breeding, migrating, and wintering waterbirds. We hypothesized that changes in marsh elevation were not sufficient to keep pace with those of sea level in both vegetated and unvegetated Spartina alterniflora sites at a number of mid lagoon marsh areas along the Atlantic Coast. We also predicted that northern areas would suffer less of a deficit than would southern sites. Beginning in August 1998, we installed surface elevation tables at study sites on Cape Cod, Massachusetts, southern New Jersey, and two locations along Virginia's eastern shore. We compared these elevation changes over the 4-4.5 yr record with the long-term (> 50 yr) tidal records for each locale. We also collected data on waterbird use of these sites during all seasons of the year, based on ground surveys and replicated surveys from observation platforms. Three patterns of marsh elevation change were found. At Nauset Marsh, Cape Cod, the Spartina marsh surface tracked the pond surface, both keeping pace with regional sea-level rise rates. In New Jersey, the ponds are becoming deeper while marsh surface elevation remains unchanged from the initial reading. This may result in a submergence of the marsh in the future, assuming sea-level rise continues at current rates. Ponds at both Virginia sites are filling in, while marsh surface elevation rates do not seem to be keeping pace with local sea-level rise. An additional finding at all sites was that subsidence in the vegetated marsh surfaces was less than in unvegetated areas, reflecting the importance of the root mat in stabilizing sediments. The implications to migratory waterbirds are significant. Submergence of much of the lagoonal marsh area in Virginia and New Jersey over the next century could have major negative (i.e., flooding) effects on nesting populations of marsh-dependent seaside sparrows Ammodramus maritimus, saltmarsh sharp-tailed sparrows Ammodramus caudacutus, black rails Laterallus jamaicensis, clapper rails Rallus longirostris, Forster's terns Sterna forsteri, common terns Sterna hirundo, and gull-billed terns Sterna nilotica. Although short-term inundation of many lagoonal marshes may benefit some open-water feeding ducks, geese, and swans during winter, the long-term ecosystem effects may be detrimental, as wildlife resources will be lost or displaced. With the reduction in area of emergent marsh, estuarine secondary productivity and biotic diversity will also be reduced.
Keywords: Sea Ducks - General; Habitat

High tides and rising seas: Potential effects on estuarine waterbirds - Erwin, R. Michael; Sanders, Geoffrey M.; Prosser, Diann J.; Cahoon, Donald R. (Studies in Avian Biology, 2006)
Coastal waterbirds are vulnerable to water-level changes especially under predictions of accelerating sea-level rise and increased storm frequency in the next century. Tidal and wind-driven fluctuations in water levels affecting marshes, their invertebrate communities, and their dependent waterbirds are manifested in daily, monthly, seasonal, annual, and supra-annual (e.g., decadal or 18.6-yr) periodicities. Superimposed on these cyclic patterns is a long-term (50-80 yr) increase in relative sea-level rise that varies from about 2-4 + mm/yr along the Atlantic coastline. At five study sites selected on marsh islands from Cape Cod, Massachusetts to coastal Virginia, we monitored marsh elevation changes and flooding, tide variations over time, and waterbird use. We found from longterm marsh core data that marsh elevations at three of five sites may not be sufficient to maintain pace with current sea-level rise. Results of the short-term (3-4 yr) measures using surface elevation tables suggest a more dramatic difference, with marsh elevation change at four of five sites falling below relative sea-level rise. In addition, we have found a significant increase (in three of four cases) in the rate of surface marsh flooding in New Jersey and Virginia over the past 70-80 yr during May-July when waterbirds are nesting on or near the marsh surface. Short-term, immediate effects of flooding will jeopardize annual fecundity of many species of concern to federal and state agencies, most notably American Black Duck (Anas rubripes), Nelson's Sharp-tailed Sparrow (Ainniodrannts nelsoni), Saltmarsh Sharp-tailed Sparrow (A. caudacn tits), Seaside Sparrow (A. niariffina), Coastal Plain Swamp Sparrow (Melospiza georgiana nigrescens), Black Rail (Laterallus jamaicensis), Forster's Tern (Sterna forsteri). Gull-billed Tern (S. nilotica), Black Skimmer (Rynchops niger), and American Oystercatcher (Haentotopus palliatus). Forster's Terns are probably most at risk given the large proportion of their breeding range in the mid-Atlantic and their saltmarsh specialization. At a scale of 1-2 decades, vegetation changes (saltmeadow cordgrass [Spartina patens] andsalt grass [Distichlis spicata] converting to smooth cordgrass [Spartina alternifloral), interior pond expansion and erosion of marshes will reduce nesting habitat for many of these species, but may enhance feeding habitat of migrant shorebirds and/or migrant or wintering waterfowl. At scales of 50-100 yr, reversion of marsh island complexes to open water may enhance populations of open-bay waterfowl, e.g., Bufflehead (Bucephala albeola) and Canvasback (Aythya valisneria), but reduce nesting habitats dramatically for the above named marsh-nesting species, may reduce estuarine productivity by loss of the detrital food web and nursery habitat for fish and invertebrates, and cause redistribution of waterfowl, shorebirds, and other species. Such scenarios are more likely to occur in the mid- and north Atlantic regions since these estuaries are lower in sediment delivery on average than those in the Southeast. A simple hypothetical example from New Jersey is presented where waterbirds are forced to shift from submerged natural marshes to nearby impoundments, resulting in roughly a 10-fold increase in density. Whether prey fauna are sufficiently abundant to support this level of increase remains an open question, but extreme densities in confined habitats would exacerbate competition, increase disease risk, and possibly increase predation.
Keywords: Conservation; Sea Ducks - General

Conclusions, synthesis, and future directions: Understanding sources of population change - Esler, D., P. L. Flint, D. V. Derksen, J.-P. L. Savard, and J. M. Eadie (Studies in Avian Biology, 2015)
The chapters in this volume of Studies in Avian Biology reflect the burgeoning interest in sea ducks, both as study species with compelling and unique ecological attributes and as taxa of conservation concern. In this review, we provide perspective on the current state of sea duck knowledge by highlighting key findings in the preceding chapters that are of particular value for understanding or influencing population change. We also introduce a conceptual model that characterizes links among topics covered by individual chapters and places them in the context of demographic responses. Last, we offer recommendations for areas of future research that we suggest will have importance for understanding and managing population dynamics of sea ducks.
Keywords: Conservation; Abundance, Distribution, & Trends

CESSATION OF OIL EXPOSURE IN HARLEQUIN DUCKS AFTER THE EXXON VALDEZ OIL SPILL: CYTOCHROME P4501A BIOMARKER EVIDENCE - Esler, D.; Ballachey, B. E.; Bowen, L.; Miles, A. K.; Dickson, R. D.; Hendersonk, J. D. (ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY, 2017)
The authors quantified hepatic hydrocarbon-inducible cytochrome P4501A (CYP1A) expression, as ethoxyresorufin-Odeethylase (EROD) activity, in wintering harlequin ducks (Histrionicus histrionicus) captured in Prince William Sound, Alaska (USA), during 2011, 2013, and 2014 (22-25 yr following the 1989 Exxon Valdez oil spill). Average EROD activity was compared between birds from areas oiled by the spill and those from nearby unoiled areas. The present study replicated studies conducted from 1998 to 2009 demonstrating that harlequin ducks using areas oiled in 1989 had elevated EROD activity, indicative of oil exposure, up to 2 decades post spill. In the present study, it was found that average EROD activity during March 2011 was significantly higher in wintering harlequin ducks captured in oiled areas relative to unoiled areas, which the authors interpret to indicate that harlequin ducks continued to be exposed to residual Exxon Valdez oil up to 22 yr after the original spill. However, the 2011 results also indicated reductions in exposure relative to previous years. Average EROD activity in birds from oiled areas was approximately 2 times that in birds from unoiled areas in 2011, compared with observations from 2005 to 2009, in which EROD activity was 3 to 5 times higher in oiled areas. It was also found that average EROD activity during March 2013 and March 2014 was not elevated in wintering harlequin ducks from oiled areas. The authors interpret these findings to indicate that exposure of harlequin ducks to residual Exxon Valdez oil abated within 24 yr after the original spill. The present study finalizes a timeline of exposure, extending over 2 decades, for a bird species thought to be particularly vulnerable to oil contamination in marine environments. Published 2016 Wiley Periodicals Inc. on behalf of SETAC.
Times Cited in Web of Science Core Collection: 6 Total Times Cited: 6 Cited Reference Count: 50
Keywords: Harlequin duck; ALASKA; 1A INDUCTION; BAY CRUDE-OIL; Biomarkers; Cytochrome P450; EROD ACTIVITY; Exxon Valdez oil spill; HYDROCARBON EXPOSURE; Oil spills; PRINCE-WILLIAM-SOUND; RECOVERY; RIVER OTTERS; SEA OTTERS; SITE-SPECIFIC CONTAMINANTS

Cytochrome P4501A biomarker indication of the timeline of chronic exposure of Barrow's goldeneyes to residual Exxon Valdez oil - Esler, Daniel; Ballachey, Brenda E.; Trust, Kimberly A.; Iverson, Samuel A.; Reed, John A.; Miles, A. Keith; Henderson, John D.; Woodin, Bruce R.; Stegeman, John J.; McAdie, Malcolm; Mulcahy, Daniel M.; Wilson, Barry W. (Marine Pollution Bulletin, 2011)
We examined hepatic EROD activity, as an indicator of CYP1A induction, in Barrow's goldeneyes captured in areas oiled during the 1989 Exxon Valdez spill and those from nearby unoiled areas. We found that average EROD activity differed between areas during 2005, although the magnitude of the difference was reduced relative to a previous study from 1996/1997, and we found that areas did not differ by 2009. Similarly, we found that the proportion of individuals captured from oiled areas with elevated EROD activity (>= 2 times unoiled average) declined from 41% in winter 1996/1997 to 10% in 2005 and 15% in 2009. This work adds to a body of literature describing the timelines over which vertebrates were exposed to residual Exxon Valdez oil and indicates that, for Barrow's goldeneyes in Prince William Sound, exposure persisted for many years with evidence of substantially reduced exposure by 2 decades after the spill. (C) 2010 Elsevier Ltd. All rights reserved.
Keywords: Nonbreeding Seasons; Contaminants; Barrow's Goldeneye; Bucephala islandica

Cross-seasonal dynamics in body mass of male Harlequin Ducks: a strategy for meeting costs of reproduction - Esler, Daniel; Bond, Jeanine C. (Canadian Journal of Zoology, 2010)
Considerations of acquisition of energy for reproduction by waterfowl have disproportionately focused on females, although males also require energy for reproduction. We quantified variation in body mass of male Harlequin Ducks (Histrionicus histrionicus (L., 1758)) on coastal wintering areas prior to spring migration, as well as on breeding grounds, to determine when and where nutrients were acquired to meet costs of reproduction. Male mass on wintering grounds increased, on average, by 45 g (7%) in the weeks prior to migration. On breeding streams, we inferred that body mass of paired males decreased with the length of time on breeding grounds. Also, on average, male mass was considerably lower on breeding streams than when they departed coastal wintering sites. We conclude that males store nutrients on marine wintering grounds for subsequent use during the breeding season. Male Harlequin Ducks are highly vigilant while on breeding streams and the associated reduction in feeding time presumably requires energy stores. We suggest that males have evolved a strategy that is at least partially "capital" for meeting costs of reproduction, in which they acquire an optimal amount of energy reserves prior to spring migration and subsequently invest them in behaviours that can enhance reproductive success.
Keywords: Breeding Season; Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Energetics and Nutrition

Correlates of Harlequin Duck densities during winter in Prince William Sound, Alaska - Esler, Daniel; Bowman, Timothy D.; Dean, Thomas A.; O'Clair, Charles E.; Jewett, Stephen C.; McDonald, Lyman L. (Condor, 2000)
We evaluated relationships of Harlequin Duck (Histrionicus histrionicus) densities to habitat attributes, history of habitat contamination by the 1989 Exxon Valdez oil spill, and prey biomass density and abundance during winters 1995-1997 in Prince William Sound, Alaska. Habitat features that explained variation in duck densities included distance to streams and reefs, degree of exposure to wind and wave action, and dominant substrate type. After accounting for these effects, densities were lower in oiled than un-oiled areas, suggesting that population recovery from the oil spill was not complete, due either to lack of recovery from initial oil spill effects or continuing deleterious effects. Prey biomass density and abundance were not strongly related to duck densities after accounting for habitat and area effects. Traits of Harlequin Ducks that reflect their affiliation with naturally predictable winter habitats, such as strong site fidelity and intolerance of increased energy costs, may make their populations particularly vulnerable to chronic oil spill effects and slow to recover from population reductions, which may explain lower densities than expected on oiled areas nearly a decade following the oil spill.
Keywords: Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Contaminants; Habitat

Densities of Barrow's Goldeneyes during winter in Prince William Sound, Alaska in relation to habitat, food and history of oil contamination - Esler, Daniel; Bowman, Timothy D.; O'Clair, Charles E.; Dean, Thomas A.; McDonald, Lyman L. (Waterbirds, 2000)
We evaluated variation in densities of Barrow's Goldeneyes (Bucephala islandica) during winter at 214 sites within oiled and unoiled study areas in Prince William Sound, Alaska in relation to physical habitat attributes, prey biomass, and history of habitat contamination by the 1989 Exxon Valdez oil spill. Using general linear model analyses, we found that goldeneye densities were positively associated with occurrence of a stream within 200 m, lack of exposure to wind and waves, and mixed (versus rocky) substrate. We speculate that these associations relate to habitat profitability via selection of beneficial attributes and avoidance of detrimental features. We also determined that biomass of blue mussels (Mytilus trossulus), the primary prey, was not related to Barrow's Goldeneye densities; we suggest that mussel standing stock exceeds predation demands in our study areas and, thus, does not dictate goldeneye distribution. After accounting for habitat effects, we detected no effect of history of oil contamination on Barrow's Goldeneye densities, suggesting that populations have recovered from the oil spill. Although other studies documented hydrocarbon exposure in Barrow's Goldeneyes through at least 1997, either the level of exposure did not affect populations via reductions in survival, or effects of oil exposure were offset by immigration.
Keywords: Nonbreeding Seasons; Contaminants; Habitat; Barrow's Goldeneye; Bucephala islandica

Harlequin duck population recovery following the 'Exxon Valdez' oil spill: Progress, process and constraints - Esler, Daniel; Bowman, Timothy D.; Trust, Kimberly A.; Ballachey, Brenda E.; Dean, Thomas A.; Jewett, Stephen C.; O'Clair, Charles E. (Marine Ecology Progress Series, 2002)
Following the 1989 'Exxon Valdez' oil spill in Prince William Sound, Alaska, we studied the status of recovery of harlequin duck Histrionicus histrionicus populations during 1995 to 1998. We evaluated potential constraints on full recovery, including (1) exposure to residual oil; (2) food limitation; and (3) intrinsic demographic limitations on population growth rates. In this paper, we synthesize the findings from our work and incorporate information from other harlequin duck research and monitoring programs to provide a comprehensive evaluation of the response of this species to the 'Exxon Valdez' spill. We conclude that harlequin duck populations had not fully recovered by 1998. Furthermore, adverse effects continued as many as 9 yr after the oil spill, in contrast to the conventional paradigm that oil spill effects on bird populations are short-lived. These conclusions are based on the findings that (1) elevated cytochrome P450 (CYP1A) induction on oiled areas indicated continued exposure to oil in 1998; (2) adult female winter survival was lower on oiled than unoiled areas during 1995 to 1998; (3) fall population surveys by the Alaska Department of Fish and Game indicated numerical declines in oiled areas during 1995 to 1997; and (4) densities on oiled areas in 1996 and 1997 were lower than expected using models that accounted for effects of habitat attributes. Based on hypothesized links between oil contamination and demography, we suggest that harlequin duck population recovery was constrained primarily by continued oil exposure. Full population recovery will also be delayed by the time necessary for intrinsic population growth to allow return to pre-spill numbers following cessation of residual oil spill effects. Although not all wildlife species were affected by the 'Exxon Valdez' oil spill, and some others may have recovered quickly from any effects, harlequin duck life history characteristics and benthic, nearshore feeding habits make them susceptible to both initial and long-term oil spill effects.
Keywords: Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Contaminants; Population Dynamics

Female Harlequin Duck Winter Survival 11 to 14 Years After the Exxon Valdez Oil Spill - Esler, Daniel; Iverson, Samuel A. (Journal of Wildlife Management, 2010)
In the mid-to late 1990s, nearly a decade after the 1989 Exxon Valdez oil spill, female harlequin ducks (Histrionicus histrionicus) suffered reduced winter survival in oiled areas of Prince William Sound, Alaska, USA, relative to unoiled areas. We conducted follow-up studies from winters 2000-2001 to 2002-2003 to determine whether differential survival persisted and to evaluate whether individual-level indices of oil exposure were related to survival. Using radiotelemetry, we tracked 138 female harlequin ducks from November through March over three winters. We analyzed variation in survival in relation to season, area oiling history, age class, body mass, and an index to exposure to residual oil based on cytochrome P4501A (CYP1A) induction. We determined that survival was most strongly related to season and age class, with evidence of higher survival in late winter and after hatch year (AHY) categories, respectively. We estimated cumulative winter survival for AHY females to be 0.837 (+/- 0.064) and 0.834 (+/- 0.065) on unoiled and oiled areas, respectively, and we estimated hatch-year female cumulative winter survival at 0.766 (+/- 0.138) on unoiled areas and 0.758 (+/- 0.152) on oiled areas. Despite persistence of oil in some intertidal areas and evidence of contaminant ingestion by harlequin ducks during and beyond this study, neither area nor CYP1A were strongly related to variation in survival, suggesting that direct effects of the oil spill on harlequin duck demography had largely abated by the winters 2000-2001 to 2002-2003. Our findings offer an unprecedented description of the timeline of effects of exposure to spilled oil and contribute to a body of literature that describe demographic effects of the Exxon Valdez oil spill that persisted over a much longer time than previously assumed. An appreciation for the timescale of chronic effects of oil spills, as well as potential for demographic effects related to much lower concentrations of oil than during the immediate period of acute effects following a spill, will provide wildlife managers with a basis for risk assessment and plans for mitigation when confronted with large spills or chronic pollution.
Keywords: Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Contaminants; Population Dynamics; Survival

Genetic and demographic criteria for defining population units for conservation: The value of clear messages - Esler, Daniel; Iverson, Samuel A.; Rizzolo, Daniel J. (Condor, 2006)
In a recent paper on Harlequin Duck (Histrionicus histrionicus) interannual site fidelity (Iverson et al. 2004), we concluded that wintering populations were demographically structured at a finer geographic scale than that at which genetic differentiation was observed and that conservation efforts should recognize this degree of demographic independence. In a critique of our study, Pearce and Talbot (2006) contend that our measures of fidelity were not robust and imply that in the face of "mixed messages" we failed to appreciate the role of genetic data in defining population units. We recognize, as we did in our original paper, that our methods for quantifying site fidelity have some limitations; however, the patterns in our data are consistent with a considerable body of literature indicating high winter site fidelity in Harlequin Ducks. Moreover, we do not consider differences in the scales at which genetic and demographic structure are expressed to be "mixed messages," given the different spatial and temporal scales at which genetic and contemporary demographic processes operate. We emphasize that a lack of genetic differentiation does not necessarily preclude the existence of contemporary demographic structure with relevance for conservation.
Keywords: Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Dispersal; Population Delineation

Testing assumptions for unbiased estimation of survival of radiomarked harlequin ducks - Esler, Daniel; Mulcahy, Daniel M.; Jarvis, Robert L. (Journal of Wildlife Management, 2000)
Unbiased estimates of survival based on individuals outfitted with radiotransmitters require meeting the assumptions that radios do not affect survival, and animals for which the radio signal is lost have the same survival probability as those for which fate is known. In most survival studies, researchers have made these assumptions without testing their validity. We tested these assumptions by comparing interannual recapture rates (and, by inference, survival) between radioed and unradioed adult female harlequin ducks (Histrionicus histrionicus), and for radioed females, between right-censored birds (i.e., those for which the radio signal was lost during the telemetry monitoring period) and birds with known fates. We found that recapture rates of birds equipped with implanted radiotransmitters (21.6 +- 3.0%; x +- SE) were similar to unradioed birds (21.7 +- 8.6%), suggesting that radios did not affect survival. Recapture rates also were similar between right-censored (20.6 +- 5.1%) and known-fate individuals (22.1 +- 3.8%), suggesting that missing birds were not subject to differential mortality. We also determined that capture and handling resulted in short-term loss of body mass for both radioed and unradioed females and that this effect was more pronounced for radioed birds (the difference between groups was 15.4 +- 7.1 g). However, no difference existed in body mass after recapture 1 year later. Our study suggests that implanted radios are an unbiased method for estimating survival of harlequin ducks and likely other species under similar circumstances.
Keywords: Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Techniques

Winter survival of adult female harlequin ducks in relation to history of contamination by the Exxon Valdez oil spill - Esler, Daniel; Schmutz, Joel A.; Jarvis, Robert L.; Mulcahy, Daniel M. (Journal of Wildlife Management, 2000)
Harlequin duck (Histrionicus histrionicus) life-history characteristics make their populations particularly vulnerable to perturbations during nonbreeding periods. The 1989 Exxon Valdez oil spill was a major perturbation to nonbreeding habitats of harlequin ducks in Prince William Sound, Alaska, which resulted in population injury. To assess the status of population recovery from the oil spill and to evaluate factors potentially constraining full recovery, we used radiotelemetry to examine survival of adult female harlequin ducks during winters of 1995-96, 1996-97, and 1997-98. We implanted 294 harlequin ducks (154 and 140 in oiled and unoiled areas, respectively) with transmitters and tracked their signals from aircraft during October through March. We examined variation in survival rates relative to area and season (early, mid, and late winter) through comparisons of models using Akaike's information criterion (AICc) values. The 3 models best supported by the data indicated that survival of birds in oiled areas was lower than in unoiled areas. Inclusion of standardized body mass during wing molt in the 3 best models did not improve their fit, indicating that body mass during wing molt did not affect subsequent winter survival. In the model that best fit our data, survival was high in early winter for both areas, lower during mid and late winter seasons, and lowest in oiled areas during mid winter. Cumulative winter survival estimated from this model was 78.0% (SE = 3.3%) in oiled areas and 83.7% (SE = 2.9%) in unoiled areas. We determined that area differences in survival were more likely related to oiling history than intrinsic geographic differences. Based on a demographic model, area differences in survival offer a likely mechanism for observed declines in populations on oiled areas. Concurrent studies indicated that harlequin ducks continued to be exposed to residual Exxon Valdez oil as much as 9 years after the spill. We suggest that oil exposure, mortality, and population dynamics were linked and conclude that continued effects of the oil spill likely restricted recovery of harlequin duck populations through at least 1998.
Keywords: Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Contaminants; Population Dynamics; Survival

Cytochrome P4501a Biomarker Indication of Oil Exposure in Harlequin Ducks up to 20 Years after the Exxon Valdez Oil Spill - Esler, Daniel; Trust, Kimberly A.; Ballachey, Brenda E.; Iverson, Samuel A.; Lewis, Tyler L.; Rizzolo, Daniel J.; Mulcahy, Daniel M.; Miles, A. Keith; Woodin, Bruce R.; Stegeman, John J.; Henderson, John D.; Wilson, Barry W. (Environmental Toxicology and Chemistry, 2010)
Hydrocarbon-inducible cytochrome P4501A (CYP1A) expression was measured, as ethoxyresorufin-O-deethylase (EROD) activity, in livers of wintering harlequin ducks (Histrionicus histrionicus) captured in areas of Prince William Sound, Alaska, USA, oiled by the 1989 Exxon Valdez spill and in birds from nearby unoiled areas, during 2005 to 2009 (up to 20 years following the spill). The present work repeated studies conducted in 1998 that demonstrated that in harlequin ducks using areas that received Exxon Valdez oil, EROD activity was elevated nearly a decade after the spill. The present findings strongly supported the conclusion that average levels of hepatic EROD activity were higher in clucks from oiled areas than those from unoiled areas during 2005 to 2009. This result was consistent across our sampling periods; furthermore, results generated from two independent laboratories using paired liver samples from one of the sampling periods were similar. The EROD activity did not vary in relation to age, sex, or body mass of individuals, nor did it vary strongly by season in birds collected early and late in the winter of 2006 to 2007. indicating that these factors did not confound inferences about observed differences between oiled and unoiled areas. We interpret these results to indicate that harlequin chicks continued to be exposed to residual Exxon Valdez oil up to 20 years after the original spill. This adds to a growing body of literature suggesting that oil spills have the potential to affect wildlife for much longer time frames than previously assumed. Environ. Toxicol. Chem. 2010;29:1138-1145. (C) 2010 SETAC
Keywords: Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Contaminants

Comparison of lead residues among avian bones - Ethier, A. L. M.; Braune, B. M.; Scheuhammer, A. M.; Bond, D. E. (Environmental Pollution, 2007)
To determine if significant differences exist in lead (Pb) accumulation in different bones, especially those most often used for bone-Pb studies in wildlife, we compared Ph concentrations in radius, ulna, humerus, femur, and tibia of Common Eider (Somateria mollissima); and radius/ulna (combined), femur, and tibia of American Woodcock (Scolopax minor). There were no significant differences in bone-Pb concentrations among woodcock bones over a wide range of Ph concentrations (3-311 mu g/g). In eider, where bone-Pb concentrations were low (< 10 mu g/g), leg bones had significantly higher Ph concentrations (approximately 30-40%) than wing bones from the same individuals. The variation among individual birds was greater than the variation among different bones within a bird. Based on our findings, we conclude that one type of bone may be substituted for another in bone-Pb studies although the same bone type should be analyzed for all birds within a study, whenever possible. Crown Copyright (c) 2006 Published by Elsevier Ltd. All rights reserved.
Keywords: Common Eider; Contaminants; Somateria mollissima

Does shooting disturbance affect diving ducks wintering on large shallow lakes? A case study on Lough Neagh, Northern Ireland - Evans, Darren M.; Day, Keith R. (Biological Conservation, 2001)
Waterfowl hunting is widespread and common throughout Europe, affecting waterfowl populations directly through the kill and indirectly through disturbance. Freedom from such disturbance is an important part of waterfowl management. However, most studies of the effects of disturbance on duck populations have been site specific with few attempts to synthesis the results of these local studies and use them in management strategies. Lough Neagh has the largest surface area of any freshwater lake in the British Isles. It is also relatively shallow with a mean depth of ca. 9 m. The seasonal effects of shooting disturbance on the daytime distributions and behaviour of wintering Pochard Aythya ferina, Tufted Duck A. fuligula, Scaup A. marila and Goldeneye Bucephala clangula was studied during the winter of 1998/1999. The nocturnal use of shoreline areas was also studied using an image-intensifing telescope. The distributions of wintering Pochard, Tufted duck and Scaup were shown to be affected by shooting disturbance on Lough Neagh. But because they were also shown to predominantly roost during the day, and were not observed to forage in the marginal areas of the Lough throughout the winter period at night, any energetic consequence of shoreline based shooting disturbance is likely to be small. Goldeneye predominantly fed during the day. It would be expected that diurnal feeding Goldeneye would show the biggest response to shooting disturbance during the day, but proportions observed in designated zones during and after the shooting season did not change significantly, confirming the lack of effect. Observation of Pochard and Tufted Duck engaged in various behaviours did show an increase in the proportion of ducks feeding, after the shooting season had closed. The increase was attributed to increased feeding prior to migration as opposed to being the result of the cessation of shooting disturbance. The most important factors to consider when applying conservation measures to diving duck populations wintering on lakes with similar attributes are identified and discussed.
Keywords: Conservation; Nonbreeding Seasons; Bucephala clangula; Common Goldeneye; Habitat

Migration patterns and sex ratios of diving ducks wintering in Northern Ireland with specific reference to Lough Neagh - Evans, Darren M.; Day, Keith R. (Ringing and Migration, 2001)
Several duck species exhibit differential migration, whereby females settle further south than males on the winter grounds after the autumn migration. This is most exaggerated in the diving ducks. In Northern Ireland generally, the migration patterns of Common Pochard Aythya ferina, Tufted Duck A. fuligula, Greater Scaup A. marila, and Common Goldeneye Bucephala clangula are similar to those observed in Great Britain. On Lough Neagh in particular, the sex ratios of wintering flocks of diving ducks were observed between the winters of 1996 and 1999. On average, 79% of Common Pochard, 72% of Tufted Duck and 66% of Common Goldeneye wintering on Lough Neagh were male. The possible reasons for differential migration of the sexes include body size dimorphism resulting in different cold temperature tolerances, advantages for males in returning to breeding grounds sooner and intersexual competition excluding the less competitive females to areas further south.
Keywords: Behavior; Nonbreeding Seasons; Migration; Bucephala clangula; Common Goldeneye

Hunting disturbance on a large shallow lake: The effectiveness of waterfowl refuges - Evans, Darren M.; Day, Keith R. (Ibis, 2002)
Disturbance is most likely to have an impact during those periods of the annual cycle when food is scarce and birds have difficulty in meeting their energy requirements. The provision of disturbance-free refuges has been shown to enhance the abundance and diversity of waterfowl wintering on such sites. Lough Neagh, a large shallow lake in Northern Ireland, hosts internationally important numbers of wintering waterfowl, the most numerous being Common Pochard Aythya ferina, Tufted Duck A. fuligula, Greater Scaup A. marila and Common Goldeneye Bucephala clangula. Hunting is the predominant winter recreational activity. A small number of refuges have been provided to limit the effects of shooting disturbance on the wintering populations. The use of one of these refuges (Doss Bay) was studied during the winter of 1997/8 and compared with a non-refuge site (Brockish Bay) during the winter of 1998/9. Shooting intensity was greater at weekends than midweek, and significantly more birds used the refuge at weekends than midweek during the shooting season. In contrast, significantly fewer birds were observed in Brockish Bay at weekends. This trend ceased when the shooting season closed, suggesting that the effect was due to shooting disturbance. Furthermore, significantly fewer birds used Doss Bay after the shooting season had closed, whereas significantly more birds were observed at Brockish Bay. Shooting disturbance had the greatest impact on dabbling duck species and rails at both sites. Diving ducks moved away from shoreline disturbance to shallow areas where they could still feed. The value of shoreline refuges for waterfowl populations on lakes is discussed.
Keywords: Conservation; Nonbreeding Seasons; Bucephala clangula; Common Goldeneye; Habitat

A comparison of the characteristics and fate of Barrow's Goldeneye and Bufflehead nests in nest boxes and natural cavities - Evans, Matthew R.; Lank, David B.; Boyd, W. Sean; Cooke, Fred (Condor, 2002)
Barrow's Goldeneye (Bucephala islandica) and Bufflehead (B. albeola) are cavity-nesting waterfowl that have received considerable attention in studies using nest boxes, but little is known about their nesting ecology in natural cavities. We found larger clutch size, lower nesting success, and different major predators for Barrow's Goldeneyes nesting in boxes versus those nesting in natural cavities, but few differences for Bufflehead. These differences are attributed to the location and physical differences between Barrow's Goldeneye nest boxes and natural cavities that affect their conspicuousness to predators and conspecific nest-parasitizing females. Goldeneye boxes were concentrated in highly visible locations such as trees at water or forest edge. Natural cavity nests, on the other hand, were often abandoned Pileated Woodpecker (Dryocopus pileatus) cavities, which were more dispersed throughout the forest interior and concealed under dense canopy cover. Bufflehead natural cavity nests were typically closer to edges, which may account for their similarity with boxes. We conclude that in some respects, studies of Barrow's Goldeneye that use nest boxes may not be representative of birds nesting in natural cavities, whereas those of Bufflehead are more likely to be so.
Keywords: Breeding Season; Techniques; Habitat; Bucephala albeola; Bufflehead; Barrow's Goldeneye; Bucephala islandica

Numbers of wintering seaducks, divers and grebes in the Moray Firth, 1977-1995 - Evans, Richard J. (Scottish Birds, 1998)
Numbers and distribution of seaducks, divers and grebes in the Moray Firth were monitored for 18 consecutive winters. Most sections within the firth held nationally important concentrations of at least one species. The Moray Firth as a whole held internationally important numbers of Red-breasted Mergansers and Slavonian Grebes and nationally important numbers of Scaup, Eiders, Common and Velvet Scoters, Long-tailed Ducks, Goldeneyes, Goosanders and Red-throated and Black-throated Divers. Peak numbers for individual species occurred in different months from September to April. Numbers of Common and Velvet Scoters and Goosanders declined during the study period and numbers of Goldeneyes, Red-breasted Mergansers and Slavonian Grebes increased. There were changes in the distribution of Eiders and Scaup within the firth. Oil pollution had no obvious effect during the study period, but remains a potential threat. These nationally important concentrations of seaducks, divers and grebes have had no adequate statutory protection to date.
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons

Oldsquaws Nesting in Association with Arctic Terns at Churchill Manitoba - Evans, R. M. (Wilson Bulletin, 1970)
Keywords: Breeding Season; Clangula hyemalis; Long-tailed Duck

Seasonal variation in accumulation of persistent organic pollutants in an Arctic marine benthic food web - Evenset, A.; Hallanger, I. G.; Tessmann, M.; Warner, N.; Ruus, A.; Borga, K.; Gabrielsen, G. W.; Christensen, G.; Renaud, P. E. (Science of the Total Environment, 2016)
The aim of the present study was to investigate seasonal variation in persistent organic pollutant (POP) concentrations, as well as food-web biomagnification, in an Arctic, benthic marine community. Macrozoobenthos, demersal fish and common eiders were collected both inside and outside of Kongsfjorden, Svalbard, during May, July and October 2007. The samples were analysed for a selection of legacy chlorinated POPs. Overall, low levels of POPs were measured in all samples. Although POP levels and accumulation patterns showed some seasonal variation, themagnitude and direction of change was not consistent among species. Overall, seasonality in bioaccumulation in benthic biota was less pronounced than in the pelagic systemin Kongsfjorden. In addition, the results indicate that delta N-15 is not a good predictor for POP-levels in benthic food chains. Other factors, such as feeding strategy (omnivory, necrophagy versus herbivory), degree of contact with the sediment, and a high dependence on particulate organic matter (POM), with low POP-levels and high delta N-15-values (due to bacterial isotope enrichment), seem to govern the uptake of the different POPs and result in loads deviating from what would be expected consulting the trophic position alone. (C) 2015 Elsevier B.V. All rights reserved.
Evenset, A. Hallanger, I. G. Tessmann, M. Warner, N. Ruus, A. Borga, K. Gabrielsen, G. W. Christensen, G. Renaud, P. E. A
Keywords: Common Eider; Contaminants; Somateria mollissima

Retinometra-Albeolae New-Species Cestoda Hymenolepididae from the Bufflehead Duck Bucephala-Albeola L - Ewart, M. J.; McLaughlin, J. D. (Canadian Journal of Zoology, 1990)
Retinometra albeolae n. sp. is described from bufflehead ducks (Bucephala albeola L.) from Manitoba, Canada. It is armed with eight skrjabinoid rostellar hooks 69-75 .mu.m long, and has a cirrus sac 240-480 .mu.m long that extends to approximately the midline of mature proglottids, a trilobed ovary, and a lobed vitelline gland. Staphylepis indica and S. meggitti, currently included in the genus Retinometra, are returned to Staphylepis on the basis of proglottid morphology and the apparent lack of a cirrus stylet in both species.
Keywords: Breeding Season; Bucephala albeola; Bufflehead; Parasites

Helminths from Spring and Fall Migrant Bufflehead Ducks Bucephala-Albeola at Delta Manitoba Canada - Ewart, M. J.; McLaughlin, J. D. (Canadian Journal of Zoology, 1990)
The digestive tracts of one local, eight spring migrant, and 16 fall migrant bufflehead ducks (Bucephala albeola L.) collected at Delta, Manitoba, were examined for helminths. Twenty-five species (5 nematode, 8 trematode, 11 cestode, and 1 acanthocephalan) were found. Thirteen species occurred in both spring and fall migrants, four occurred in spring migrants only, and six were found only in fall migrants. The species composition of the helminth fauna of buffleheads resembles that of lesser scaup more closely than that of any other anatid species studied to date.
Keywords: Nonbreeding Seasons; Bucephala albeola; Bufflehead; Parasites

Organochlorine Compounds in Tissues of Golden Eye Velvet Scoter Eider and Coot Wintering in Gdansk Bay Poland 1975-1976 - Falandysz, J. (Bromatologia i Chemia Toksykologiczna, 1986)
During 1975-1976, a survey was conducted to determine the residues of hexachlorobenzene (HCB), alpha-, beta-, and gamma-hexachlorocyclobexane (.SIGMA. BHC), p, p'-DDE and p, p'-DDT (.SIGMA. DDT), and polychlorinated biphenyls, (PCBs) in breast muscles, liver, and adipose tissue of diving ducks (golden eye - Bucephala clangula, velvet scoter - Melanitta fusca, eider - Somateria mollissima) and coot (Fulica atra) wintering in Gdansk Bay, Baltic Sea. Birds under examination were found dead and were gathered on the beaches around the Bay or taken from fishing nets in nearshore region of the Bay. It was found that healthy ducks taken from fishing nets contained considerably lower levels of HCB, .SIGMA. BHC, .SIGMA. DDT, and PCBs in extractable lipids from breast muscles and liver (maximum 0.19, 0.24, 5.2, 17.0 mg/kg, and 1.8, 1.5, 130.0, and 21.0 mg/kg, respectively) than birds found dead (9.4, 13.9, 250.0, and 890.0 mg/kg, and 16.0, 14.0, 170.0, 250.0 mg/kg, respectively). The mean level of HCB, .SIGMA. BHC, .SIGMA. DDT, and PCBs in lipids extracted from the breast muscles and liver of twelve coots that died probably because of starvation and adverse weather conditions, was 1.5, 0.26, 46.0, 130.0 mg/kg, and 2.3, 0.19, 76.0, 150.0 mg/kg, respectively.
Keywords: Melanitta fusca; Nonbreeding Seasons; White-winged Scoter; Contaminants

Chlorinated Hydro Carbons in Diving Ducks Wintering in Gdansk Bay Baltic Sea - Falandysz, J.; Szefer, P. (Science of the Total Environment, 1982)
The levels of HCB [hexachlorobenzene fungicide], .alpha.BHC, .gamma.-BHC, DDT (plus analogs) and PCB [polychlorinated biphenyl] were determined in adipose fat from 7 spp. of diving ducks [Aythya fuligula, A. marila, Bucephala clangula, Clangula hyemalis, Melanitta fusca, M. nigra, Somateria mollissima] at their winter quarters in the southern Baltic. PCB, .SIGMA.DDT and HCB were detected in all samples. PCB was highest, followed by .SIGMA.DDT and HCB. Residues of .gamma.-BHC were detected in 4 of 129 samples, but for all samples from the long-tailed duck, only levels of .alpha.-BHC were positive. Differences between HCB, .SIGMA.DDT and PCB residue levels between males and females of the scaup duck were statistically insignificant (P < 0.01).
Keywords: Sea Ducks - General; Nonbreeding Seasons; Contaminants

Perfluorinated compounds in some terrestrial and aquatic wildlife species from Poland - Falandysz, J.; Taniyasu, S.; Yamashita, N.; Rostkowski, P.; Zalewski, K.; Kannan, K. (Journal of Environmental Science and Health Part A Toxic-Hazardous Substances & Environmental Engineering, 2007)
Perfluorooctanesulfonate (PFOS) at 1.6 - 39 ng/g ww and 4.8 - 200 pg/mL, respectively, perfluorooctanoate (PFOA) at 0.06 - 0.28 ng/g ww and < 0.05 - 1.8 pg/mL, and perfluorodecanoate (PFDA) at 0.13 - 0.57 ng/g ww and 0.05 - 1.8 pg/mL, were detected in all specimens of European Beaver's (Castor fiber) liver as well as in whole blood of Cod (Gadus morhua), Velvet Scoter (Melanitta fusca), Eider Duck (Sommateria mollisima), Long-tailed Duck (Clangula hyemalis), Razorbill (Alca torda), Red-throated Diver (Gavia stellata) sampled in Poland. At smaller concentrations and at less frequency was perfluorononanoate (PFNA) at 0.05 - 1.4 ng/g ww and < 0.2 - 2 pg/mL, perfluorohexanoate (PFHxA) at 0.03 - 0.23 ng/g ww and < 0.05 - 0.69 pg/mL, while perfluorohexanesulfonate (PFHxS) at 0.05 - 4.3 pg/mL and perfluorooctanesulfonamidoacetate (PFOSA) at 0.1 - 13 pg/mL were also found in Cod as well as in molluscivorous diving-ducks and fish-eating birds but not in Beaver, while perfluoroheptanoate (PFHpA) at < 0.05 - 0.74 pg/mL was found only in Cod.
Keywords: Common Eider; Melanitta fusca; White-winged Scoter; Clangula hyemalis; Long-tailed Duck; Contaminants; Somateria mollissima

Embedded lead shot and infliction rates in common eiders Somateria mollissima and king eiders S. spectabilis wintering in southwest Greenland - Falk, Knud; Merkel, Flemming; Kampp, Kaj; Jamieson, Sarah E. (Wildlife Biology, 2006)
The large numbers of common ciders Somateria mollissima and king ciders S. spectabilis wintering in southwest Greenland are subject to intensive hunting, and in addition to direct harvest an unknown number of birds are wounded and become carriers of embedded lead shot. We conducted the first assessment of the magnitude of this undesirable side effect of hunting in Greenland by X-raying 879 common and 114 king eiders collected by local fishermen and hunters during three winters (2000-2002). On average, 22% of all common eiders carried embedded shot, but proportions were strongly age dependent; of first-winter (1W) birds 13.2%, of immatures (IM) 16.4%, and of adults (AD) 29.1% were carriers. For king eiders the proportions were similar: 11.3, 10 and 20%, respectively, were carriers. Adult common ciders collected in fjord areas were significantly less burdened (24.5%) than birds collected in the more heavily hunted coastal areas (35.0%). Among inflicted birds, 1W birds contained more pellets (mean 2.2) than AD (mean 1.7), despite the adults' longer time to accumulate pellets from multiple inflictions, which suggests that the most burdened juveniles die before entering the older age class. From the proportion of wounded I W birds (13.2%) we modelled the infliction rates, i.e. the proportion of an age class that become pellet carriers each year, for older birds (IM+AD) to be at least 1.8-3%, assuming that annual survival of adult eiders falls within the range 0.8-0.9. Assuming that roughly 35% of the 463,000 common ciders estimated to winter in southwest Greenland are juveniles, 13% are immatures, and 52% adults (fourth winter and older), then each winter up to 30,000 ciders would become new carriers of embedded shot (2 1,000 juveniles, 1,200-1,800 immatures and 4,800-7,300 adults). As wounded birds may risk increased mortality in severe winters and reduced reproductive output, the infliction has implications for the demographic models used to assess sustainable eider harvest levels. There is a need for follow-up studies of regional variation in infliction, and to identify ways to possibly reduce the hunters' unintended impact on their game populations.
Keywords: Conservation; Common Eider; Nonbreeding Seasons; Somateria mollissima; King Eider; Somateria spectabilis

Long Nights, Airplanes, and Avian Surgery: A Tale of Working With Volunteers to Study Long-tailed Ducks (Clangula hyemalis) Wintering on Lake Michigan - Fara, L. J.; Ford, S.; Lubinski, B. R.; Houdek, S. C.; Eichholz, M. W. (JOURNAL OF AVIAN MEDICINE AND SURGERY, 2019)
Evidence suggests that wintering populations of long-tailed ducks along the Atlantic and Pacific coasts are in decline, but little is known about wintering populations on Lake Michigan. Researchers seek answers to basic questions regarding habitat use and migration patterns (temporal and spatial) of long-tailed ducks that winter on Lake Michigan, by using surgically implanted satellite transmitters. The processes of locating the birds, capturing and implanting satellite transmitters, and interpreting the results were challenging, and efforts relied on dedicated researchers, veterinarians, resource managers, and many volunteers.
Times Cited in Web of Science Core Collection: 0 Total Times Cited: 0 Cited Reference Count: 9

Effects of Implanted Satellite Transmitters on Behavior and Survival of Female Common Eiders - Fast, P. L. F.; Fast, M.; Mosbech, A.; Sonne, C.; Gilchrist, H. G.; Descamps, S. (Journal of Wildlife Management, 2011)
Times Cited: 1 Fast, Peter L. F. Fast, Marie Mosbech, Anders Sonne, Christian Gilchrist, H. Grant Descamps, Sebastien Fast, Peter/B-5131-2013; Sonne, Christian/I-7532-2013; Mosbech, Anders/J-6591-2013 Mosbech, Anders/0000-0002-7581-7037 2
Keywords: survival; common eider; Behavior; Breeding Season; Techniques; somateria mollissima

Experimental evaluation of nest shelter effects on weight loss in incubating common eiders Somateria mollissima - Fast, Peter L. F.; Gilchrist, H. Grant; Clark, Robert G. (Journal of Avian Biology, 2007)
Evaluating consequences of habitat selection is an important step in understanding life history strategies and behavioural decisions of animals. Kilpi and Lindstrom (1997) found that incubating common eiders Somateria mollissima on exposed, treeless islands lost weight faster than females nesting on wooded islands and proposed that this difference was due to adverse incubation conditions at exposed nests. Therefore, we tested whether common eiders gained an advantage when nesting in sheltered habitats by placing artificial shelters over randomly-selected females after the onset of incubation within an eider colony in arctic Canada. We predicted that sheltered females would be heavier on completion of incubation than control hens lacking shelters. Females nesting in artificial shelters experienced a more moderate thermal environment at both cold and warm temperature extremes. Eiders nesting in shelters were heavier than control females during mid incubation, consistent with habitat-specific rates of weight loss reported by Kilpi and Lindstrom (1997). Natural overhead cover was available at potential nests but few eiders used those sites. We suspect that microclimatic advantages offered by sheltered sites may be offset by costs of increased female vulnerability to predators. Further work is needed to test this hypothesis, and to determine mechanisms responsible for lower weight loss in eiders attending well concealed nests.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Energetics and Nutrition; Habitat

Nest-site materials affect nest-bowl use by Common Eiders (Somateria mollissima) - Fast, Peter L. F.; Gilchrist, H. Grant; Clark, Robert G. (Canadian Journal of Zoology, 2010)
Nest-site characteristics influence reproductive success in birds. Most studies of nest-site selection evaluate nest characteristics following the commencement of egg-laying, possibly overlooking the importance of pre-existing nest-site features that may be altered during the nesting process. Because Common Eiders (Somateria mollissima (L.,1758)) often lay their eggs in nest bowls created in previous years, we were able to experimentally place moss or feather down in nest bowls prior to nesting. We then quantified whether these materials increased nest establishment or advanced laying dates relative to control nests and nests where material was removed prior to arrival of nesting females. We found no difference in the likelihood of successful nest establishment between groups. However, the onset of incubation occurred 2-3 days earlier in nest bowls that contained feather down versus nest bowls with little or no nesting material. Nest bowls containing feathers or vegetation may be selected first if they increase nest survival, perhaps by enhancing egg concealment during the critical early-laying period. The presence of material for egg concealment may be particularly important in nesting environments where tall or dense vegetation is not available to provide nest cover.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Habitat

STABLE CARBON AND NITROGEN ISOTOPE DISCRIMINATION FACTORS FOR QUANTIFYING SPECTACLED EIDER NUTRIENT ALLOCATION TO EGG PRODUCTION - Federer, R. N.; Hollmen, T. E.; Esler, D.; Wooller, M. J. (Condor, 2012)
Times Cited: 0 Federer, Rebekka N. Hollmen, Tuula E. Esler, Daniel Wooller, Matthew J. 0
Keywords: Breeding Season; Somateria fischeri; Spectacled Eider; Techniques; energetics and Nutrition

Stable carbon and nitrogen isotope discrimination factors from diet to blood plasma, cellular blood, feathers, and adipose tissue fatty acids in Spectacled Eiders (Somateria fischeri) - Federer, R. N.; Hollmen, T. E.; Esler, D.; Wooller, M. J.; Wang, S. W. (Canadian Journal of Zoology, 2010)
Stable isotope analyses of animal tissues can be used to infer diet through application of mixing models. An important component in a mixing model is the incorporation of stable isotope discrimination factors so that isotopic shifts between diet and tissues built from the diet can be accounted for when comparing tissues to potential food sources. We determined the stable carbon and nitrogen isotopic discrimination factors between lipid-free diet and blood plasma, cellular blood, and adult chest contour feathers for captive female Spectacled Eiders (Somateria fischeri (Brandt, 1847)). Mean discrimination factors for blood components and feathers were either similar or slightly larger compared with previously studied species. Additionally, we determined the stable carbon isotope discrimination factors between dietary lipids and adipose tissue fatty acids using three adipose tissue biopsies from captive male Spectacled Eiders that were fed three different diet treatments. Isotopic signatures of adipose tissue fatty acids closely reflected shifts in the diet and were either similar to or increased relative to diet. Our study provides a foundation for research using tissues as end-members in stable isotope nutrient allocation models and foraging ecology studies of Spectacled Eiders, and will provide the most applicable isotope data to date for sea ducks.
Keywords: Somateria fischeri; Spectacled Eider; Energetics and Nutrition; Techniques; Trophic Interactions

The Diet of Red-Breasted Mergansers Mergus-Serrator During the Smolt Run in Northeast Scotland Uk the Importance of Salmon Salmo-Salar Smolts and Parr - Feltham, M. J. (Journal of Zoology (London), 1990)
Salmon (Salmo salar) formed the large proportion by mass of fish found in the stomachs of red-breasted mergansers (Mergus serrator) shot during the smolt run in north-east Scotland. Salmon parr represented approximately two-thirds by mass of juvenile salmon eaten, whilst smolts were present in a smaller proportion than previously predicted. The median lengths of parr and smolts eaten were 70 and 115 mm, respectively; the latter being significantly smaller than the smolt population sampled during annual production estimates on the river.
Keywords: Trophic Interactions; Mergus serrator; Red-breasted merganser

Consumption of Atlantic salmon smolts and parr by goosanders: Estimates from doubly-labelled water measurements of captive birds released on two Scottish rivers - Feltham, M. J. (Journal of Fish Biology, 1995)
The field metabolic rates (FMRs) of nine captive goosanders, Mergus merganser, released on two Scottish rivers were estimated using the doubly-labelled water (DLW) technique. Mean (+- S.E.) FMR was 2.322 +- 0.239 ml CO-2 g-1 h-1 and daily energy expenditure (DEE) 1939 +- 184 kJ per day. This was significantly greater ( times 1.5) than previous estimates which assumed DEE to be three times the basal metabolic rate (BMR) based on regression equations predicting BMR from body mass. FMR of captives and dietary data from previous studies were used to estimate daily consumption of salmon, Salmo salar, smolts and parr by natural populations of these ducks on the river North Esk, north-east Scotland. Goosanders are likely to consume 480-522 g fish per day of which two-thirds are juvenile salmon: equivalent to a daily intake of 10-11 smolts and 48-52 parr. Annual predation of smolts by goosanders was estimated to be between 8000 and 15 000 or 3 and 16% of annual production.
Keywords: Energetics and Nutrition; Trophic Interactions; Common merganser; Mergus merganser

Predation of Atlantic salmon, Salmo salar L., smolts and parr by red-breasted mergansers, Mergus serrator L., on two Scottish rivers - Feltham, M. J. (Fisheries Management and Ecology, 1995)
Current models estimating the impact of red-breasted mergansers, Mergus serrator L., on salmon, Salmo salar L., fisheries in Scotland fail to take account of any annual variation in the proportion of the diet that is smolts. During the 1987-1990 smolt runs, the annual variation in the diet of mergansers was estimated from the stomach contents of birds shot on two Scottish rivers. The proportion of salmon in the diet was greatest early in the smolt run (76-91% by weight), and contained proportionately more smolts than later in the run, when coarse fish were more prominent. There was little annual variation in the proportion of the diet that was juvenile salmon. However, the proportion of these fish that were smolts, was twice as great in some years than in others and this appeared to be independent of estimated annual smolt production in the rivers.
Keywords: Trophic Interactions; Mergus serrator; Red-breasted merganser

Carlin tag recoveries as an indicator of predation on salmon smolts by goosanders and red-breasted mergansers - Feltham, M. J.; MacLean, J. C. (Journal of Fish Biology, 1996)
Between 1984 and 1990 a total 221 Carlin tags used to mark salmon Salmo salar smolts in the River North Esk, NE Scotland, were recovered from the stomachs of goosanders Mergus merganser and red-breasted mergansers M. serrator. Both Carlin-tagging and adipose-clipping affected the predation of salmon smolts by sawbill ducks. The mean ( +- S.D.) sizes of tagged smolts taken by both species were similar (117 +- 3 mm) and significantly smaller than the mean sizes of smolts in the river, possibly due to a reduction in the swimming performance of small smolts bearing tags. Large adipose-clipped smolts ( gtoreq mean smolt size) were predated significantly more than unclipped smolts, but no such difference was observed for small smolts ( lt mean smolt size). Data suggested that some ducks cued into smolt release sites where they took a disproportionately high number of tagged smolts on or near the day of release and continued to do so for several days. Although tag recoveries are commonly used to estimate the impact of piscivores on fish stocks, our study suggests that some predators respond to the presence of tagged fish in ways that directly reflect the tagging procedure and that caution should be exercised when extrapolating conclusions based on such data to untagged fish.
Keywords: Techniques; Trophic Interactions; Common merganser; Mergus merganser; Mergus serrator; Red-breasted merganser

Incubating Wood Duck Aix-Sponsa and Hooded Merganser Mergus-Cucullatus Hens Killed by Black Rat Snakes Elaphe-Obsoleta - Fendley, T. T. (Wilson Bulletin, 1980)
Keywords: Breeding Season; Trophic Interactions; Hooded Merganser; Lophodytes cucullatus

DNA double-strand breaks in incubating female common eiders (Somateria mollissima): Comparison between a low and a high polluted area - Fenstad, A. A.; Bustnes, J. O.; Bingham, C. G.; Ost, M.; Jaatinen, K.; Moe, B.; Hanssen, S. A.; Moody, A. J.; Gabrielsen, K. M.; Herzke, D.; Lierhagen, S.; Jenssen, B. M.; et al. (ENVIRONMENTAL RESEARCH, 2016)
Alterations in the genetic material may have severe consequences for individuals and populations. Hence, genotoxic effects of environmental exposure to pollutants are of great concern. We assessed the impact of blood concentrations of persistent organic pollutants (POPs) and mercury (Hg) on DNA double strand break (DSB) frequency, in blood cells of a high-exposed Baltic, and lower exposed Arctic population of common eiders (Somateria mollissima). Furthermore, we examined whether the genotoxic response was influenced by antioxidant concentration (plasma total glutathione (tGSH) and total antioxidant capacity) and female body mass. The DNA DSB frequency did not differ between the two populations. We found significant positive relationships between Hg and DNA DSB frequency in Baltic, but not in Arctic eiders. Although both p,p'-DDE and PCB 118 had a lesser effect than Hg, they exhibited a positive association with DNA DSB frequency in Baltic eiders. Antioxidant levels were not important for the genotoxic effect, suggesting alternative mechanisms other than GSH depletion for the relationship between Hg and DNA DSBs. Hence, the Baltic population, which is considered to be endangered and is under the influence of several environmental stressors, may be more susceptible to genotoxic effects of environmental exposure to Hg than the Arctic population. (C) 2016 Elsevier Inc. All rights reserved.
Times Cited in Web of Science Core Collection: 11 Total Times Cited: 12 Cited Reference Count: 63
Keywords: PERSISTENT ORGANIC POLLUTANTS; OXIDATIVE STRESS; Mercury; PCB; CONTAMINATED GULL EGGS; FASTING SEABIRD; GEL-ELECTROPHORESIS; Genotoxicity; HUMAN-LYMPHOCYTES; IN-VITRO; LARUS-HYPERBOREUS; MICRONUCLEUS TEST; MOLECULAR-MECHANISMS; p,p '-DDE; Seabirds

Blood and feather concentrations of toxic elements in a Baltic and an Arctic seabird population - Fenstad, A. A.; Bustnes, J. O.; Lierhagen, S.; Gabrielsen, K. M.; Ost, M.; Jaatinen, K.; Hanssen, S. A.; Moe, B.; Jenssen, B. M.; Krokje, A. (MARINE POLLUTION BULLETIN, 2017)
We report blood and feather concentrations of elements in the Baltic Sea and Arctic population of common eiders (Somateria mollissima). The endangered Baltic Sea population of eiders was demonstrably affected by element pollution in the 1990s. While blood concentrations of Hg were higher in Baltic breeding eiders, blood Se, As and Cd concentrations were higher in Arctic eiders. Blood concentrations of Pb, Cr, Zn and Cu did not differ between the two populations. While blood Pb concentrations had declined in Baltic eiders since the 1990s, Hg concentrations had not declined, and were above concentrations associated with adverse oxidative effects in other bird species. Inconsistent with blood concentrations, feather concentrations suggested that Pb, Zn, and Cd exposure was higher in Baltic eiders, and that Hg exposure was higher in Arctic eiders. Our study thus emphasizes the need for comprehensive evaluation of toxic element status, covering the annual cycle of a species. (C) 2016 Elsevier Ltd. All rights reserved.
Times Cited in Web of Science Core Collection: 21 Total Times Cited: 21 Cited Reference Count: 84
Keywords: MERCURY; OXIDATIVE STRESS; TRACE-ELEMENTS; SEA; Common eiders; EIDER SOMATERIA-MOLLISSIMA; Environmental exposure; Heavy metals; HEAVY-METAL CONTAMINATION; MARINE BIRDS; NESTING COMMON EIDERS; Pollution; SELENIUM; SURFACE SEDIMENTS; Svalbard

PERSISTENT ORGANIC POLLUTANT LEVELS AND THE IMPORTANCE OF SOURCE PROXIMITY IN BALTIC AND SVALBARD BREEDING COMMON EIDERS - Fenstad, A. A.; Jenssen, B. M.; Gabrielsen, K. M.; Ouml;st, M.; Jaatinen, K.; Bustnes, J. O.; Hanssen, S. A.; Moe, B.; Herzke, D.; Krokje, A. (Environmental Toxicology and Chemistry, 2016)
The distance to sources and the long-range transport potential of persistent organic pollutants (POPs) are important in understanding the impact of anthropogenic pollution on natural seabird populations. The present study documented blood concentrations of POPs in the Baltic Sea (Tvarminne, Finland) population of common eiders (Somateria mollissima) in 2009 and in 2011 and compared the concentrations with the presumably less exposed Arctic population in Svalbard (Kongsfjorden, Norway). The Baltic population had 26, 10, and 5 times greater concentrations of hexachlorocyclohexane, polychlorinated biphenyls, and p,p'-dichlorodiphenyldichloroethylene than the Svalbard population. Unexpectedly, concentrations of chlordanes were higher in Svalbard eiders, whereas concentrations of hexachlorobenzenes (HCBs) did not differ between the 2 populations. Although the similar HCB levels may partly be explained by the high transport potential of HCBs, unknown factors may have been more important than distance to sources and long-range transport potential for the chlordanes. One plausible explanation may be that the fasting-related redistribution of POPs from fat to blood was greater throughout the incubation in Arctic eiders, causing them to have higher blood levels of these POPs at the end of incubation. The blood concentrations of POPs in Baltic eiders were higher than documented in any other eider population and were comparable to levels in seabirds feeding at higher trophic positions in the food chain. (C) 2015 SETAC
Fenstad, Anette A. Jenssen, Bjorn M. Gabrielsen, Kristin M. Ost, Markus Jaatinen, Kim Bustnes, Jan O. Hanssen, Sveinn A. Moe, Borge Herzke, Dorte Krokje, Ase
Keywords: Common Eider; Contaminants; Somateria mollissima

DNA Double-Strand Breaks In Relation To Persistent Organic Pollutants In Fasting Common Eiders (Somateria Molissima) - Fenstad, A. A.; Jenssen, B. M.; Moe, B.; Hanssen, S. A.; Bingham, C.; Herzke, D.; Bustnes, J. O.; Krokje, A. (Mutagenesis, 2014)
Fenstad, Anette A. Jenssen, Bjorn Munro Moe, Borge Hanssen, Sveinn A. Bingham, Chris Herzke, Dorte Bustnes, Jan O. Krokje, Ase
Keywords: Breeding Season; Common Eider; Contaminants; Somateria mollissima

DNA double-strand breaks in relation to persistent organic pollutants in a fasting seabird - Fenstad, A. A.; Jenssen, B. M.; Moe, B.; Hanssen, S. A.; Bingham, C.; Herzke, D.; Bustnes, J. O.; Krokje, A. (Ecotoxicology and Environmental Safety, 2014)
Lipophilic persistent organic pollutants (POPs) are released from fat reserves during fasting, causing increased blood concentrations. Thus, POPs represent a potential anthropogenic stressor during fasting periods. We analysed the blood of female common eiders (Somateria mollissima) by using agarose gel electrophoresis and image data analysis to quantify the DNA-fraction, of total DNA, that migrated into the gel (DNA-FTM) as a relative measure of DNA double strand-breaks (DSBs) during the fasting incubation period in the high arctic. In 2008 and in 2009 blood samples were obtained for analysis of 9 POPs and DNA-FTM at day 5 of the incubation period, and then in the same individuals at day 20. This unique study design gave us the opportunity to analyse the same individuals throughout two points in time, with low and high stress burdens. During the incubation period the body mass (BM) decreased by 21-24%, whereas the POP levels increased by 148-639%. The DNA-FTM increased by 61-67% (being proportional to the increase in DSBs). At day 5, but not day 20, DNA-FTM was positively correlated with most analysed POPs. The increase in DNA-FTM was positively correlated with the decrease in BM (g) during incubation. Thus, we suggest that fasting stress (BM loss) decreases DNA integrity and that stress caused by fasting on BM loss appeared to override the additional stress caused by concurrent increase in levels of the analysed POPs in the eiders. Blood levels of POPs in the eiders in Svalbard were relatively low, and additive and/or synergistic genotoxic effects of fasting stress and POP exposure may occur in populations with higher POP levels. (C) 2014 Elsevier Inc. All rights reserved.
Fenstad, Anette A. Jenssen, Bjorn M. Moe, Borge Hanssen, Sveinn A. Bingham, Chris Herzke, Dorte Bustnes, Jan O. Krokje, Ase
Keywords: Breeding Season; Common Eider; Contaminants; Somateria mollissima

Antioxidant Responses in Relation to Persistent Organic Pollutants and Metals in a Low- and a High-Exposure Population of Seabirds - Fenstad, A. A.; Moody, A. J.; Ost, M.; Jaatinen, K.; Bustnes, J. O.; Moe, B.; Hanssen, S. A.; Gabrielsen, K. M.; Herzke, D.; Lierhagen, S.; Jenssen, B. M.; Krokje, A. (Environmental Science & Technology, 2016)
Oxidative stress occurs when there is an imbalance between the production of reactive oxygen species (ROS) and antioxidant defense. Exposure to pollutants may increase ROS and affect antioxidant levels, and the resulting oxidative stress may negatively affect both reproduction and survival. We measured concentrations of 18 persistent organic pollutants (POPs) and 9 toxic elements hi blood, as well as total antioxidant capacity (TAC), total glutathione (tGSH), and carotenoids in plasma of Baltic and Arctic female common eiders (Somateria mollissima) (N = 54) at the end of their incubation-related fasting. The more polluted Baltic population had higher TAC and tGSH concentrations compared to the Arctic population. Carotenoid level's did not differ between populations. The effect of mixtures of pollutants on the antioxidants was assessed, and the summed molar blood concentrations of 14 POPs were positively related to TAC. There was no significant relationship between the analyzed pollutants and tGSH concentrations. The adaptive improvement of the antioxidant defense system in the Baltic population, may be a consequence of increased oxidative stress. However, both increased oxidative stress and energy allocation toward antioxidant defense may have adverse consequences for Baltic eiders at the incubation stage, when energy resources reach an annual minimum due to incubation-related fasting.
Fenstad, Anette A. Moody, A. John Ost, Markus Jaatinen, Kim Bustnes, Jan O. Moe, Borge Hanssen, Sveinn A. Gabrielsen, Kristin M. Herzke, Dorte Lierhagen, Syverin Jenssen, Bjorn M. Krokje, Ase
Keywords: Breeding Season; Common Eider; Contaminants; Somateria mollissima

Notes on the Breeding of the Common Scoter Melanitta-Nigra in Ireland - Ferguson, A. (Irish Naturalists' Journal, 1971)
Keywords: Breeding Season; Black Scoter; Melanitta nigra

High contrast panels and lights do not reduce bird bycatch in Baltic Sea gillnet fisheries - Field, R.; Crawford, R.; Enever, R.; Linkowski, T.; Martin, G.; Morkunas, J.; Morkune, R.; Rouxel, Y.; Oppel, S. (GLOBAL ECOLOGY AND CONSERVATION, 2019)
Bycatch is a cause of mortality among marine mammals, sea turtles, fish and birds. For some species this mortality may be sufficient to cause population declines. The Baltic Sea is a global 'hotspot' for bird bycatch in gillnet fisheries and is globally important for wintering sea ducks, but no technical solution has been found yet to reduce bird bycatch in gillnet fisheries in the Baltic. Here, we report on trials conducted in the Baltic Sea to test whether two different gillnet modifications with visual stimuli can effectively reduce bird bycatch while maintaining volume of fish caught. We conducted paired trials of two types of visual stimuli attached to nets: 1) high contrast monochrome net panels and 2) net lights (constant green and flashing white LED lights). We measured the amount of fish and birds caught in standard nets and those modified with the visual stimuli. Neither of the two most commonly caught species, Long- tailed Ducks (Clangula hyemalis) and Velvet Scoters (Melanitta fusca), were deterred from lethal encounters with nets by either black-and-white panels or by steady green or flashing white net lights. Long-tailed Ducks were caught in larger numbers in nets equipped with flashing white net lights than in unmodified nets at the same location. Catch rates of commercial fish were not affected by net lights or net panels placed within the nets. Hence, while the deterrents that we tested successfully maintained fish catch, they failed to reduce bird bycatch and are therefore ineffective. We discuss likely avenues for future investigation of bycatch mitigation methods for gillnet fisheries, including species and location response to net lights, managed fishery closures, above-water distraction of birds and gear switching. (C) 2019 The Authors. Published by Elsevier B.V.
Times Cited in Web of Science Core Collection: 26 Total Times Cited: 26 Cited Reference Count: 55
Keywords: CONSERVATION; ECOLOGY; TURTLE BYCATCH; ALBATROSSES; Bycatch; Coastal gillnet fisheries; EYESPOTS; Fisheries; LONGLINE; MEGAFAUNA; Mitigation; PORPOISE PHOCOENA-PHOCOENA; Sea duck; Seabird; SEABIRD BYCATCH

Alterations of riverine ecosystems adversely affect bird assemblages - Figarski, T.; Kajtoch, L. (Hydrobiologia, 2015)
The alteration of flow regimes is the most serious threat to the environment and populations of riverine ecosystems. The aim of this study was to verify how newly recovered assemblages of riverine birds react to recent and intensive water control transformations. Data on habitat transformations, breeding bird species and population abundance within submontane river channels in southern Poland were compared before and after river regulation. Regulation works affected approximately one-third of river sections in the drainages studied. Simultaneously, large amounts of gravel, clay and woody debris were removed from river channels, and river channels became overgrown by dense vegetation. Regulation works carried out in river channels, previously restored by severe flood, led to a strong decline in breeding bird assemblages (23% decrease of species richness and 33% decrease of population abundance). These results show that river regulation can significantly alter the structure of breeding bird assemblages, and such change is generally negative for bird diversity (especially for rare and vulnerable species). Riverine habitats are some of the most important biodiversity hotspots and major routes of migration for organisms in Europe, so the degradation of riverine ecosystems can have a catastrophic impact on nature in the entire European Union.
Figarski, Tomasz Kajtoch, Lukasz
Keywords: Conservation; Breeding Season; Mergus merganser; Habitat; Common Merganser

Offshore Flight of Buffleheads, Bucephala albeola, After Twilight in Winter: An Anti-Predation Tactic? - Finley, James K. (Canadian Field-Naturalist, 2007)
In winter, oil Vancouver island, Buffleheads depart from coastal marine feeding habitat shortly after the onset of civil twilight. This precisely-timed phenomenon may have evolved in response to predation pressure from Peregrine Falcons, Falco peregrinus. The dual habitat requirements of Buffleheads in Shoal Harbour Migratory Bird Sanctuary (1931) and Sidney Channel Important Bird Area are to be included within the proposed Gulf Islands National Marine Conservation Area.
Keywords: Behavior; Nonbreeding Seasons; Bucephala albeola; Bufflehead

The Punctual Bufflehead, Bucephala albeola: Autumn Arrivals in Shoal Harbour Sanctuary, Vancouver Island, in Relation to Freeze-up - Finley, James K. (Canadian Field-Naturalist, 2007)
Buffleheads are punctual in their return to wintering grounds on the Pacific coast. First arrivals appeared in Shoal Harbour Migratory Bird Sanctuary, southeastern Vancouver Island, on the 288(th) day of the year on average (+/- S.D. 2.3; n = 10), that is. 15 October. This vanguard preceded the first peak influx by about 15-20 days, and a second influx by about 24-26 days. First arrivals usually appeared by mid-morning, and included singles (females on two occasions) and small flocks of up to eight. First arrivals may represent a photoperiodic threshold, whereas subsequent peak influxes represent climatic thresholds associated with freeze-up. The phenology of Bufflehead autumn migrations is a good proxy indicator of the advance of the zero degree isotherm, and thus of climatic variability. The timing of their autumn migrations does not appear to have changed in the last half of the twentieth century, consistent with evidence that freeze-up has not advanced. Monitoring of their migrations, in conjunction with shore-based observations of freeze-up, would validate one-dimensional thermodynamic models of freeze-up, and provide a more ecologically meaningful index of climate change, at minimal cost.
Keywords: Behavior; Nonbreeding Seasons; Bucephala albeola; Bufflehead

Feeding behavior and food habits of wintering Harlequin Ducks at Shemya Island, Alaska - Fischer, Julian B.; Griffin, Curtice R. (Wilson Bulletin, 2000)
The foraging ecology of wintering Harlequin Ducks (Histrionicus histrionicus) is poorly understood and information on basic food habits is lacking for this species in the Aleutian Islands of Alaska where the largest winter concentrations occur. We investigated feeding behavior and food habits of wintering Harlequin Ducks in the western Aleutian Islands of Alaska with respect to sex and temporal and environmental variables to document behavioral responses to winter conditions, resource use, and nutritional requirements. We found that on average, Harlequin Ducks spent most of the diurnal period feeding (70% males, 76% females). However, more time was spent feeding during evenings, midwinter, cold weather, and high tides. Gastropods, crustaceans, and diptera larvae made up 83% of the diet, but diet composition changed throughout winter. Despite change in food habits, diet energy density was stable throughout winter.
Keywords: Behavior; Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Trophic Interactions

Summer distribution of marine birds in the Western Beaufort Sea - Fischer, Julian B.; Larned, William W. (Arctic, 2004)
Proposed expansion of oil and gas development into offshore waters of the Beaufort Sea has raised concerns that marine birds could be affected by disturbance and oil spills. We conducted aerial surveys to determine the composition and distribution of avian species in the western Beaufort Sea. We sampled marine waters up to 100 km from shore, between Cape Halkett and Brownlow Point in June, July, and August of 1999 and 2000 and between Point Barrow and Demarcation Point in July 2001. Approximately 90% of the birds we observed were sea ducks, predominantly long-tailed ducks (Clangula hyematis), king eiders (Somateria spectabilis), and scoters (Melanitta spp.). Densities of most species decreased with distance from shore, although king eider densities were higher in deeper, offshore waters. Densities of long-tailed ducks increased in nearshore coastal lagoons at the onset of post-breeding moult, and densities of eiders increased offshore during their peak moult migration. In general, bird densities were highest in areas with less than 30% ice cover, although high densities of king eiders occurred in areas with 30%-60% ice cover. Our results suggest species-specific uses of the Beaufort Sea in summer for moulting, migration, brood rearing, and foraging. The vulnerability of marine birds to potential oil spills and disturbance will depend on the location of facilities, timing of events, and ice conditions.
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General; Molt; Migration; Contaminants

Spatial-genetic structuring in a red-breasted merganser (Mergus serrator) colony in the Canadian Maritimes - Fishman, D. J.; Craik, S. R.; Zadworny, D.; Titman, R. D. (Ecology and Evolution, 2011)
Times Cited: 0 Fishman, David J. Craik, Shawn R. Zadworny, David Titman, Rodger D. 0
Keywords: Breeding Season; Mergus serrator; Red-breasted merganser; Population Delineation

An assessment of the toxicological significance of anthropogenic contaminants in Canadian arctic wildlife - Fisk, Aaron T.; de Wit, Cynthia A.; Wayland, Mark; Kuzyk, Zou Zou; Burgess, Neil; Letcher, Robert; Braune, Birgit; Norstrom, Ross; Blum, Susan Polischuk; Sandau, Courtney; Lie, Elisabeth; Larsen, Hans Jorgen S.; et al. (Science of the Total Environment, 2005)
Anthropogenic contaminants have been a concern in the Canadian arctic for over 30 years due to relatively high concentrations of bioaccumulating and biomagnifying organochlorine contaminants (OCs) and toxic metals found in some arctic biota and humans. However, few studies have addressed the potential effects of these contaminants in Canadian arctic wildlife. Prior to 1997, biological effects data were minimal and insufficient at any level of biological organization. The present review summarizes recent studies on biological effects related to contaminant exposure, and compares new tissue concentration data to threshold effects levels. Weak relationships between cadmium, mercury and selenium burdens and health biomarkers in common eider ducks (Somateria mollissima borealis) in Nunavut were found but it was concluded that metals were not influencing the health of these birds. Black guillemots (Cepplius grylle) examined near PCB-contaminated Saglek Bay, Labrador, had enlarged livers, elevated EROD and liver lipid levels and reduced retinol (vitamin A) and retinyl palmitate levels, which correlated to PCB levels in the birds. Circulating levels of thyroid hormones in polar bears (Ursus maritimus) were correlated to PCB and HO-PCB plasma concentrations, but the impact at the population level is unknown. High PCB and organochlorine pesticide concentrations were found to be strongly associated with impaired humoral and cell-mediated immune responses in polar bears, implying an increased infection risk that could impact the population. In beluga whale (Delphinapterus leucas), cytocbromes P450 (phase I) and conjugating (phase II) enzymes have been extensively profiled (immunochemically and catalytically) in liver, demonstrating the importance of contaminants in relation to enzyme induction, metabolism and potential contaminant bioactivation and fate. Concentrations of OCs and metals in arctic terrestrial wildlife, fish and seabirds are generally below effects thresholds, with the possible exception of PCBs in burbot (Lota lota) in some Yukon lakes, Greenland shark (Soniniosus microcephalus), glaucous and great black-backed gulls (Larus hyperboreus and L. marinus), and TEQs of dioxin-like chemicals in seabird eggs. PCB and DDT concentrations in several arctic marine mammal species exceed effects thresholds, although evidence of stress in these populations is lacking. There is little evidence that contaminants are having widespread effects on the health of Canadian arctic organisms, with the possible exception of polar bears. However, further research and better understanding of organolialogen exposure in arctic biota is needed considering factors such as tissue levels that exceed effects thresholds, exposure to "new" organolialogen contaminants of concern, contaminated regions, and climate change. (c) 2005 Published by Elsevier B.V.
Keywords: Common Eider; Contaminants; Somateria mollissima

Abdominal implantation of transmitters in Harlequin Ducks (Histrionicus histrionicus) and Barrow's Goldeneyes (Bucephala islandica). - Fitzgerald, G.; Brodeur, S.; Robert, M. (Medecin Veterinaire du Quebec, 2001)
The use of abdominally implanted transmitters with external whip antenna in ducks is relatively new. We describe a study conducted on free-ranging 40 Harlequin Ducks and 21 Barrow's Goldeneyes between 1996 and 2001 in the province of Quebec and in Labrador with emphasis on the surgical technique. Both conventionnal and satellite transmitters were implanted. Isoflurane anesthesia, endotracheal intubation, thermoregulation and careful monitoring were considered relevant to the success of the implantation. Radio extrusion was observed in captivity with the pre-study trial of the surgical technique on two American Black Ducks (Anas rubripes). Two mortalities occurred on identified high risk patients (female in oviposition and male injured during capture), the male during the procedure revealing internal hemorrage, the female during recovery from anesthesia. Three post-release mortalities were suspected to be related to the implantation. The signal was lost for three other birds and the cause was unknown. Two female Harlequin Ducks were found dead by predation one to two months after release. Implanted birds were observed healthy as long as four years later. The study resulted in major discoveries regarding these two duck species, which are considered to be at risk in eastern North America.
Keywords: Harlequin duck; Histrionicus histrionicus; Techniques; Barrow's Goldeneye; Bucephala islandica

Pleistocene Ducks of the Old Crow Basin Yukon Territory Canada - Fitzgerald, G. R. (Canadian Journal of Earth Sciences, 1991)
Thirteen species of ducks, ranging in age from ?latest Illinoian to Holocene, have been identified from the Old Crow Basin. The most common species in the collection is the Oldsquaw (Clangula hyemalis), followed by the White-winged Scoter (Melanitta fusca). The genus Anas (six species) is well represented. The Ring-necked Duck (Aythya collaris) and the Black Scoter (Melanitta nigra) also occupied the area in the past. This shows that good habitat for ducks has existed in the area at times since the ?Illinoian and supports environmental reconstructions for the area suggesting that ?Sangamon conditions were as warm as, or warmer than, today, with ponds and streams and pockets of boreal forest. There is also evidence for inland migration of the Common Eider (Somateria mollissima).
Keywords: Common Eider; Clangula hyemalis; Long-tailed Duck; Somateria mollissima; Black Scoter; Melanitta nigra

Winter diet and weights of Barrow's and common goldeneye in southcentral Washington - Fitzner, R. E.; Gray, R. H. (Northwest Science, 1994)
Keywords: Nonbreeding Seasons; Bucephala clangula; Common Goldeneye; Energetics and Nutrition; Trophic Interactions; Barrow's Goldeneye; Bucephala islandica

Vulnerability and conservational value analysis for seabirds in connection with drilling for oil and gas in the northern Barents sea: Suggestion for additional studies - Fjeld, Per Espen; Bakken, Vidar (Norsk Polarinstitutt Meddelelser, 1993)
This assessment of the vulnerability in relation to oil and conservational value of seabirds in the northern part of the Barents Sea, is the first part of a total impact analysis for the area. As yet no simulations of oil drift have been undertaken in the assessment area. The vulnerability and conservational values arrived at here are based on the methods described by Anker-Nilssen (1987). 88 bird populations were assessed for the seasons: spring, summer, autumn and winter Of the 88 populations, a total of 64 were classified as highly or partially vulnerable in relation to oil spills. Of the 25 populations defined for the spring, 21 were classified as highly vulnerable. The most vulnerable populations were Common Eider, King Eider and Fulmar. Of the 28 populations defined for the summer season, 22 were classified as highly vulnerable. Ranking highest were the Common Eider, King Eider, Brent Goose populations, and next vulnerable were the Barnacle Goose and some auk species. Of the 26 populations defined for the autumn, 15 were classified as highly vulnerable. For the winter only 9 populations were considered, of which 6 were classified as highly vulnerable. The same 88 populations considered for vulnerability were also assessed to determine their conservational value. 13 populations were defined as having national conservational value, and 43 were defined as having international conservational value. As many of the populations considered are arctic species with limited distributions in the North Atlantic area, it is natural that these receive international protection value classification. The existing data basis was sufficient for carrying out a vulnerability assessment for most of the populations considered in this study. For the future effect analysis, however, more precise descriptions of the distribution and population size of some populations are needed. This especially applies to some rare and vulnerable species such as the King Eider and Brent Goose. Lack of suitable registration methods accounts for the inadequate knowledge of some populations, for example the Little Auk. The projects proposed in this report will provide a more substantial data basis for the final impact analysis of seabirds/oil in the northern Barents Sea area: (1) the registration of breeding and moulting geese and ducks in the Liefdefjorden-Moffen area, (2) the development of census methods for the Little Auk, and (3) the distribution of seabirds in open sea in the breeding period and in ice-covered waters in the spring.
Keywords: Breeding Season; Common Eider; Sea Ducks - General; Nonbreeding Seasons; Contaminants; King Eider

Recent Changes in Waterfowl Situation in the Lakes Myvatn and Vikingavatn Iceland - Fjeldsa, J. (Dansk Ornitologisk Forenings Tidsskrift, 1975)
Keywords: Sea Ducks - General

A review of beached bird surveys within the Wadden sea trilateral monitoring and assessment program - Fleet, David M. (Marine Ornithology, 2006)
The Trilateral Monitoring and Assessment Programme (TMAP), established in 1994, is carried out in the framework of the Trilateral Cooperation on the Protection of the Wadden Sea, which includes Denmark, Germany, and the Netherlands. Its objective is integrated monitoring and assessment of the Wadden Sea ecosystem. Beached bird surveys have been carried out on southern North Sea coasts since the 1970s (Netherlands) or the mid-1980s (Germany and Denmark). The surveys use trilateral standardized procedures and are evaluated as part of the TMAP. The results are published at regular intervals in Wadden Sea Quality Status Reports by the Common Wadden Sea Secretariat. The results of the surveys within the Wadden Sea and adjoining regions indicate steady declines in pollution levels since the mid-1980s. For example, oiling rates (the proportion of beached birds that are oiled) of the Common Guillemot Uria aalge declined on German North Sea coasts to 62% in the period 1992/93-1994/95 from 82% (n = 620) during the three winters 1984/85-1986/87 (n = 967) and to 35.5% (n = 1024) in 2001/02-2003/04. The oiling rates of pelagic and offshore species are, however, still high on southern North Sea coasts. In the period 2001/02-2003/04, the oiling rates of the Red-throated Loon Gavia stellata, Common (Black) Scorer Melanitta nigra, and the Black-legged Kittiwake Rissa tridactyla on the German North Sea coast were 80% (n = 54), 50% (n = 357), and 22% (n = 137) respectively. An Ecological Quality Objective (EcoQO), phrased as "proportion of oiled Common Guillemots among those found dead or dying on beaches," has been developed within the OSPAR Convention on the Protection of the Marine Environment of the North East Atlantic and is currently being implemented. Oiling rates for this species in the southern North Sea are currently much higher than the 10% level targeted by the EcoQO.
Keywords: Sea Ducks - General; Contaminants

A Ship Traffic Disturbance Vulnerability Index for Northwest European Seabirds as a Tool for Marine Spatial Planning - Fliessbach, K. L.; Borkenhagen, K.; Guse, N.; Markones, N.; Schwemmer, P.; Garthe, S. (FRONTIERS IN MARINE SCIENCE, 2019)
Ship traffic in Northwestern European seas is intense and continuing to increase, posing a threat to vulnerable seabird species as a result of disturbance. However, information on species-specific effects of ship traffic on seabirds at sea is limited, and tools are needed to prioritize species and areas to support the integration of conservation needs in Marine Spatial Planning. In this study, we investigated the responses of 26 characteristic seabird species in the German North and Baltic Seas to experimental ship disturbance using large datasets collected as part of the Seabirds at Sea counts. We developed a Disturbance Vulnerability Index (DVI) for ship traffic combining indicators for species' shyness, escape costs, and compensatory potential, and analyzed the relationships among shyness, escape costs, and vulnerability. The DVI was calculated using the following eight indicators: escape distance, proportion of escaping birds, proportion of birds swimming prior to disturbance, wing loading, habitat use flexibility, biogeographic population size, adult survival rate, European threat and conservation status. Species-specific disturbance responses differed considerably, with common scoters (Melanitta nigra) and red-throated loons (Gavia stellata) showing the longest escape distances and highest proportions of escaping individuals. Red-throated loon, black guillemot (Cepphus grylle), Arctic loon (Gavia arctica), velvet scoter (Melanitta fusca), and red-breasted merganser (Mergus serrator) had the highest DVI values, and gulls and terns had the lowest. Contrary to theoretical considerations, shyness correlated positively with escape costs, with the shyest species also being the most vulnerable among the species studied. The strong reactions of several species to disturbance by ships suggest the need for areas with little or no disturbance in some marine protected areas, to act as a refuge for vulnerable species. This DVI can be used in combination with distribution data to identify the areas most vulnerable to disturbance.
Times Cited in Web of Science Core Collection: 16 Total Times Cited: 16 Cited Reference Count: 109
Keywords: EIDERS SOMATERIA-MOLLISSIMA; BEHAVIORAL-RESPONSES; behavior; HABITAT LOSS; disturbance; ENERGETIC COST; escape distance; FLIGHT INITIATION DISTANCE; HAEMATOPUS-OSTRALEGUS; HUNTING DISTURBANCE; LIFE-HISTORY; MAGELLANIC PENGUINS; marine spatial planning; POPULATION CONSEQUENCES; risk-disturbance hypothesis; seabirds; ship traffic; vulnerability index

Changes in size and trends of North American sea duck populations associated with North Pacific oceanic regime shifts - Flint, P. L. (Marine Biology, 2013)
Times Cited: 0 Flint, Paul L. 0
Keywords: Population Dynamics; Sea Ducks

Population Dynamics of Sea Ducks - Flint, Paul. L (Studies in Avian Biology, 2015)
In this chapter, I explore population dynamics of sea ducks by developing population models. In determining which life history characteristics had the greatest influence on future population dynamics, adult female survival consistently had the highest sensitivity and elasticity and this result was robust across a wide range of life history parameter values. Conversely, retrospective models consistently found that the majority of annual variation in λ was associated with variation in productivity. Stochastic models that are based on process variation and incorporate correlations among life history parameters are the most useful for visualizing the probability of achieving a desired management outcome. Effective management targets both the mean and the variance of parameters and takes advantage of correlations among life history parameters. Example models demonstrate that sea duck species can achieve equal fitness using a variety of survival and productivity combinations. Sea duck populations will tend to have long time lags in terms of responding to management actions. Understanding the role of density-dependent population regulation is critical for effective sea duck management and conservation.
Keywords: Population Dynamics; Population Model

Modeling bird mortality associated with the M/V Citrus oil spill off St. Paul Island, Alaska - Flint, Paul L.; Fowler, Ada C.; Rockwell, Robert F. (Ecological Modelling, 1999)
We developed a model to estimate the number of bird carcasses that were likely deposited on the beaches of St. Paul Island, Alaska following the M/V Citrus oil spill in February 1996. Most of the islands beaches were searched on an irregular schedule, resulting in the recovery of 876 King Eider carcasses. A sub-sample of beaches were intensively studied to estimate daily persistence rate and detection probability (Fowler, A.C., Flint, P.L., 1997. Marine Pollution Bulletin). Using these data, our model predicted that an additional 733 +- 70 King Eider carcasses were not detected during our searches. Therefore, we estimate that at least 1609 +- 70 King Eider carcasses occurred on beaches as a result of the spill. We lacked sufficient sample size to model losses for other species, thus we applied the estimated recovery rate for King Eiders (54%) to other species and estimate a total combined loss of 1765 birds. In addition, 165 birds were captured alive making the total estimated numberof birds impacted by the M/V Citrus spill 1930. Given that oiled birds occurred in places on the island which could not be systematically searched combined with the fact that it was unlikely that oiled birds that died at sea would have been recovered during our searches (Flint, P.L., Fowler, A.C., 1998. Marine Pollution Bulletin), our estimate of total mortality associated with the spill should be considered a minimum.
Keywords: Nonbreeding Seasons; Contaminants; King Eider; Somateria spectabilis; Survival

Survival of spectacled eider adult females and ducklings during brood rearing - Flint, Paul L.; Grand, James B. (Journal of Wildlife Management, 1997)
We studied survival of adult female and duckling spectacled eiders (Somateria fischeri) during brood rearing on the Yukon-Kuskokwim Delta, Alaska from 1993 to 1995. Duckling survival to 30 days of age averaged 34% with a 95% confidence interval from 25 to 47%. Half (49%) of radiomarked adult females had lost all their ducklings by 30 days after hatch. Most (74%) duckling mortality occurred in the first 10 days. Adult female survival during the first 30 days of brood rearing was 93 +- 3% (SE). Females died from lead poisoning, as a result of ingesting lead shot, and predation. Mortality of adult females during brood rearing is probably higher than during other times of the year. Low adult female survival during the breeding season may be contributing to the overall population decline of spectacled eiders.
Keywords: Breeding Season; Somateria fischeri; Spectacled Eider; Contaminants; Survival

Incubation behavior of Spectacled Eiders on the Yukon-Kuskokwim Delta, Alaska - Flint, Paul L.; Grand, J. Barry (Condor, 1999)
We studied incubation behavior of Spectacled Eiders (Somateria fischeri) on the Yukon-Kuskokwim Delta in 1996. We trapped 19 females on their nests and weighed them in early incubation and again at hatch. Average daily weight loss for incubating females was 16.6 +- 1.0 g day-1, which resulted in a cumulative loss of 26% of body weight throughout incubation. Nest attendance was monitored for a portion of the incubation period using temperature sensing artificial eggs. Incubation constancy averaged 90 +- 1%. Average recess length was 37.1 +- 0.9 min, and nests cooled an average of 4.2 +- 0.1degreeC during recesses. Recess frequency averaged 2.5 +- 0.1 recesses day-1, and most recesses (70%) occurred between 10:00 and 22:00. Incubation constancy varied among females, but was not related to changes in body weight or incubation period. There was no influence of ambient temperature on incubation recess length, however most recesses were taken during the warmest part of the day. We found considerable variation among females in patterns of daily incubation constancy, nest cooling, recess frequency, and recess length. It is not clear from our results what factors constrain incubation behavior of Spectacled Eiders, but we suggest that individual females respond to a complex suite of variables.
Keywords: Behavior; Breeding Season; Somateria fischeri; Spectacled Eider; Energetics and Nutrition

Late summer survival of adult female and juvenile Spectacled Eiders on the Yukon-Kuskokwim Delta, Alaska - Flint, Paul L.; Grand, J. Barry; Morse, Julie A.; Fondell, Tom F. (Waterbirds, 2000)
We used radio-telemetry to examine survival of adult female and juvenile Spectacled Eiders (Somateria fischeri) from 30 days after hatch until departure from the Yukon-Kuskokwim Delta (YKD) during 1997-1999. Juvenile survival was 71.4%; adult female survival was 88.5%. Mink (Mustella vison) were the most common predator identified for both adults and juveniles. Detectable levels of lead were found in bones of 74% of juvenile carcasses recovered and 21% had levels indicative of acute exposure. Average age at departure was 59+-1 days old for juveniles and 56+-1 days after hatch for adults. Most broods (60.5%) departed the YKD synchronously. Overall our data indicate that mortality during the latter half of brood-rearing is higher than previously thought. We conclude that brood rearing is a period of high mortality for brood-rearing females and that lead poisoning is responsible for reductions in juvenile survival to fledging.
Keywords: Breeding Season; Somateria fischeri; Spectacled Eider; Contaminants; Survival

Breeding of Steller's Eiders, Polysticta stelleri, on the Yukon-Kuskokwim Delta, Alaska - Flint, Paul L.; Herzog, Mark P. (Canadian Field-Naturalist, 1999)
Historically, an unknown number of Steller's Eiders nested along the outer coastal fringe of the Yukon-Kuskokwim Delta, Alaska, but no nests had been found since 1975. We located six nests from 1991-1998 and we conclude that Steller's Eiders are still a regular breeder at low densities on the Yukon-Kuskokwim Delta.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Polysticta stelleri; Steller's eider

Movements of flightless long-tailed Ducks during wing molt - Flint, Paul L.; Lacroix, Deborah L.; Reed, John A.; Lanctot, Richard B. (Waterbirds, 2004)
We examined the movements of flightless Long-tailed Ducks (Clangula hyemalis) during the wing molt in the near-shore lagoons of the Beaufort Sea in Alaska. Estimates of site fidelity during the 21-day flightless period ranged from 1-100%, with considerable variation among locations and within locations among years. There was no effect of low-level experimental disturbance or an underwater seismic survey on site fidelity of molting Long-tailed Ducks. Birds molting along a relatively consistent habitat gradient were more likely to move than those molting in a fragmented habitat. While flocks of birds are consistently observed in the same locations, these data suggest considerable turnover within these aggregations. These results, in conjunction with other studies, suggest that forage is relatively uniformly distributed within lagoons. We conclude that habitat selection by molting Long-tailed Ducks is likely influenced by protection from wind and associated waves.
Keywords: Nonbreeding Seasons; Molt; Clangula hyemalis; Long-tailed Duck; Dispersal; Habitat

Survival of Common Eider Somateria mollissima adult females and ducklings during brood rearing - Flint, Paul L.; Moran, Christine L.; Schamber, Jason L. (Wildfowl, 1999)
We studied survival of adult female and duckling Common Eiders during brood rearing at two sites on the Yukon-Kuskokwim Delta, Alaska, in 1997. Duckling survival to 30 days of age was 19% +- 10% (95% CI). Seventy-three percent of radio-marked adult females had lost all their ducklings by 30 days after hatch. Duckling survival was not related to hatch date. We estimate an average of 0.84 ducklings fledged per adult female radio-marked at hatch. Most broods moved to salt water within 15 days of hatch. Adult female survival during the first 30 days of brood rearing was 96 +- 6% (95% CI). Mortality of adult females during brood rearing is probably higher than during other times of the year.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Survival

Correlated growth and survival of juvenile Spectacled Eiders: Evidence of habitat limitation? - Flint, Paul L.; Morse, Julie A.; Grand, J. Barry; Moran, Christine L. (Condor, 2006)
We studied the growth and survival of Spectacled Eider (Somateria fischeri) ducklings to 30 days of age along the lower Kashunuk River on the Yukon-Kuskokwim Delta from 1995 to 2000. We replicated this study at a second site, Kigigak Island, in 1999 and 2000. Age-adjusted estimates of duckling mass and survival at 30 days posthatching were highly variable. Duckling survival was consistently higher on Kigigak Island in 1999 and 2000, averaging 67%, while survival on the Kashunuk River averaged 45% during the same time period. Duckling survival was negatively related to hatching date. At the Kashunuk River site our data supported models that indicated age-adjusted mass varied with habitat type and declined with hatching date. Ducklings from Kashunuk River were heavier in 1999, while ducklings from Kigigak Island were heavier in 2000. However, we found a positive correlation between 30-day duckling survival and age-adjusted mass, suggesting a localized environmental effect on both parameters. We conclude that predation may be the proximate mechanism of mortality, but habitat conditions are likely the ultimate factors influencing duckling survival. Geographic variation in rates of duckling survival and apparent growth suggest that spatial heterogeneity in population vital rates is occurring at multiple levels.
Keywords: Breeding Season; Somateria fischeri; Spectacled Eider; Productivity; Physiology; Population Dynamics; Survival

Annual survival and site fidelity of Steller's eiders molting along the Alaska Peninsula - Flint, Paul L.; Petersen, Margaret R.; Dau, Christian P.; Hines, James E.; Nichols, James D. (Journal of Wildlife Management, 2000)
Populations of Steller's eiders (Polysticta stelleri) molting and wintering along the Alaska Peninsula have declined since the 1960's. We captured and marked a large sample of Steller's eiders molting in 2 lagoons along the Alaska Peninsula between 1975-97. We used mark-recapture analysis techniques to estimate annual survival and movement probabilities within and among lagoons for male and female eiders. Estimates of annual survival (+-SE) were 0.899 +- 0.032 for females and 0.765 +- 0.044 for males. Both sexes showed high rates of fidelity to specific molting locations (>95%) within lagoons; yet we found no evidence that annual probability of survival differed among groups molting in different locations either within or among lagoons. We found weak evidence that annual survival decreased between the periods 1975-81 and 1991-97. The lower survival of males compared to females is unusual for waterfowl and may result in a female-biased sex ratio. We conclude that a decrease in adult survival may have initiated the long-term population decline. Further, a shortage of males may be limiting reproductive potential.
Keywords: Molt; Dispersal; Population Dynamics; Survival; Polysticta stelleri; Steller's eider

Exposure of Spectacled Eiders and other diving ducks to lead in western Alaska - Flint, Paul L.; Petersen, Margaret R.; Grand, J. Barry (Canadian Journal of Zoology, 1997)
Lead poisoning, resulting from ingestion of spent shot, has been identified as a cause of mortality in Spectacled Eiders (Somateria fischeri) on the Yukon - Kuskokwim Delta, Alaska. We examined lead-exposure rates of adult and juvenile Spectacled Eiders and other diving ducks, using atomic absorption spectrophotometry of blood samples. Additionally, we X-rayed birds in the field to identify ingested shot. We detected shot in the gizzards of 11.6% of Spectacled Eiders X-rayed. During the period from arrival through incubation, 13.0% of adult females and 6.6% of adult males had elevated blood lead levels when captured. During the brood-rearing period, 35.8% of adult females and 12.2% of ducklings were exposed to lead when captured. There was an increase in the probability of exposure of adult females with date sampled. We predict that 50% of the successfully breeding hens were likely exposed to lead, and 25-37% of the Spectacled Eider breeding population was exposed to lead. The long-term effects of sublethal doses on Spectacled Eiders are unknown; however, exposure of nesting females and young birds to lead may result in reduced over-winter survival and (or) reduced fecundity.
Keywords: Breeding Season; Somateria fischeri; Spectacled Eider; Contaminants

Chronic hydrocarbon exposure of harlequin ducks in areas affected by the Selendang Ayu oil spill at Unalaska Island, Alaska - Flint, P. L.; Schamber, J. L.; Trust, K. A.; Miles, A. K.; Henderson, J. D.; Wilson, B. W. (Environmental Toxicology and Chemistry, 2012)
Times Cited: 1 Flint, Paul L. Schamber, Jason L. Trust, Kimberly A. Miles, A. Keith Henderson, John D. Wilson, Barry W. 1
Keywords: Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Contaminants

A contribution to the biology of the common eider - Flint, V. E. (Biull Moskovskovo Obshchestva Ispytatelei Prirody Biol, 1955)
Keywords: Common Eider; Somateria mollissima

Organochlorine Residues in New York Waterfowl Harvested by Hunters in 1983-1984 - Foley, R. E. (Environmental Monitoring and Assessment, 1992)
Thirteen organochlorine compounds were detected in fat and breast muscle tissues of Canada goose and five species of ducks that were shot by sportsman in New York. Residues of DDE and PCB occurred most frequently and were postively identified along with DDT,hepatochlor epoxide, trans-nonachlor, and hexachlorobenzene. Compounds that were detected but not positively confirmed by mass spectrometry were dieldrin, mirex, heptachlor, chlordane, oxychlordane, and endrin. Wood duck (Aix sponsa) and Canada goose (Branta canadensis) had significantly lower levels of DDE and PCB than black duck (Anas rubripes), mallard (Anas platyrhynchos), scaup (Athys sp.),and bufflehead (Bucephala albeola). Birds collected from Long Island and the Hudson River-Lake Champlain corridor carried highest concentrations.
Keywords: Nonbreeding Seasons; Contaminants; Bucephala albeola; Bufflehead

Organochlorine Contaminants in Common Goldeneye Wintering on the Niagara River New York USA - Foley, R. E.; Batcheller, G. R. (Journal of Wildlife Management, 1988)
We collected adult male common goldeneye (Bucephala clangula) near their time of arrival on wintering grounds (Nov-Dec) (n = 26) and just prior to spring migration (Feb-Mar) (2 = 24) from the Upper Niagara River (UNR), New York, to identify and measure organochlorine contaminants in fat tissues. Detectable concentrations of polychlorinated biphenyl (PCB), dichlorodiphenyldichloroethylene (DDE), dieldrin, hexachlorobenzene (HCB), oxychlordane, and heptachlor epoxide (HE) were found in all adult birds. Polychlorinated biphenyl, dieldrin, HCB, and HE increased (P < 0.05) in adults between the 2 sample periods. In a group of hatching-year (HY) birds sampled in November-December (n = 27), organochlorine residues were less than those of adults from the same period (P < 0.001). Contaminants known to occur in prey items (e.g., crustaceans, gastropods, insects, pelecypods, fish, and annelids) are probably the major source of exposure for common goldeneye on the Niagara River.
Keywords: Nonbreeding Seasons; Bucephala clangula; Common Goldeneye; Contaminants

Breeding densities, biogeography, and nest depredation of birds on Igloolik Island, Northwest Territories - Forbes, Graham; Robertson, Kelly; Ogilvie, Carey; Seddon, Laura (Arctic, 1992)
The avifauna of Igloolik Island and immediate vicinity was studied during two breeding seasons in 1985-86. This is the first study to compile an intensive record of avifaunal migration patterns and nesting activity, density and success for Igloolik Island. Data for these years are supplemented by the observations of earlier explorers and researchers. During our two seasons of survey, we rercorded 40 species of birds, of which 25 nested on the island. Combining our records, with previously published data, a total of 48 species have been recorded, with 30 species nesting. Several interspecies mating of gulls and the first confirmed breeding record of purple sandpiper (Calidris maritima) for the Melville Peninsula area were recorded. The density of breeding birds on Igloolik Island (28.5 pairs cntdot km-2) is similar to other eastern high arctic sites at that latitude. Issues realted to the biogeographic comprisons of arctic sites are discussed. In late August, the eastern end of the island acts as a significant staging area for gull species, oldsquaw (Clangula hyemalis) and arctic tern (Sterna paradisaea). A combined average of 58.3% of the nests of six species were depredated. As many as 73% of red-throated loon (Gavia stellata) and 93% of arctic tern nests suffered mainly human-related egg predation.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Sea Ducks - General

Flock Size and Density of Common Mergansers Mergus-Merganser in Northwestern California USA - Foreman, L. D. (California Fish and Game, 1979)
Keywords: Abundance, Distribution, and Trends; Common merganser; Mergus merganser

Response of Long-Tailed Duck (Clangula hyemalis) to the Change in the Main Prey Availability in Its Baltic Wintering Ground - Forni, P.; Morkunas, J.; Daunys, D. (ANIMALS, 2022)
Simple Summary Extreme change in the benthic macrofauna community after invasion of the bottom fish round goby (Neogobius melanostomus) in the eastern Baltic Sea, challenged the declining long-tailed duck (Clangula hyemalis) population at the wintering ground. The aim of this study was to assess the change in the diet of the long-tailed duck in two different seabed types: highly impacted hard-bottom and adjacent pristine soft-bottom habitats. The results showed a significant change in the diet in hard-bottom habitats, while the diet in soft-bottom habitats remained similar over time. At the same time, the body condition did not differ over time or between habitats, confirming the high foraging flexibility and the quick species response to the extreme changes in prey composition and availability. The long-tailed duck (Clangula hyemalis) is a vulnerable and declining species wintering in the Baltic Sea. The introduction of the invasive fish, the round goby (Neogobius melanostomus), dramatically impacted the benthic macrofauna in hard-bottom habitats, while no significant changes occurred in soft-bottom benthic macrofauna. Therefore, we aimed to assess the extent to which the diet of long-tailed ducks changed in two different bottom types. We analysed the stomach content of 251 long-tailed ducks bycaught in gillnets from 2016 to 2020 in hard- and soft-bottom habitats and compared these results with those published by Zydelis and Ruskyte (2005). The results show that the long-tailed duck experienced a change in diet in hard-bottom habitats, shifting from the blue mussel to Hediste diversicolor, barnacles, and fish. In soft-bottom habitats, their diet remained similar over time and was based on H. diversicolor, a few bivalve species, and Saduria entomon. There was no evidence of significant differences in diet between sex or age. Despite the abovementioned changes in diet, the average body condition of the species did not change over time or between habitats. This confirms that long-tailed ducks have high feeding flexibility and quick species response to changes in prey availability, as they are capable of shifting their diet to new prey.
Times Cited in Web of Science Core Collection: 2 Total Times Cited: 2 Cited Reference Count: 38
Keywords: body condition; long-tailed duck; Clangula hyemalis; sea duck; BEHAVIOR; Baltic Sea; benthic macrofauna; diet changes; feeding ecology; feeding selectivity; FOOD

Migratory connectivity and variation in migration phenology within the Pacific population of Barrow's Goldeneye (Bucephala islandica) - Forstner, T. M.; Boyd, W. S.; Esler, D.; Bowman, T. D.; Schamber, J. L.; McAdie, M.; Thompson, J. E.; Green, D. J. (AVIAN CONSERVATION AND ECOLOGY, 2022)
Effective management of migratory animals requires an understanding of individual movement patterns throughout the annual cycle. We used satellite transmitters to track adult Barrow's Goldeneye (Bucephala islandica) captured at five wintering sites, one breeding site, and one molting site from across the species' geographic range in western North America. The data were analyzed to assess the strength of migratory connectivity and determine latitudinal and sex effects on migration phenology. At the range-wide scale, migratory connectivity was high; cluster analyses showed subpopulations aggregated at each stage of the annual cycle. Barrow's Goldeneye from all wintering latitudes traveled north and east to breed. Compared to females, males traveled farther north to molt and consequently traveled longer distances when returning to their wintering areas. Wintering latitude had little effect on migration distance but a large effect on the phenology of migration. Individuals that wintered at northern latitudes arrived on their wintering areas earlier and departed later than individuals that wintered farther south. Individuals that wintered at northern latitudes also arrived on and left their inland breeding areas later but left their molting sites earlier than individuals that wintered farther south. Sex also influenced the phenology of migration at all sites: males left their mates during incubation and consequently spent less time on breeding areas and more time on their molting and fall staging areas. The high level of migratory connectivity observed in this study suggests that the subpopulation of Barrow's Goldeneye in south-central Alaska is demographically independent from subpopulations in southeast Alaska and British Columbia, and could be managed separately.
Times Cited in Web of Science Core Collection: 1 Total Times Cited: 1 Cited Reference Count: 85
Keywords: migratory connectivity; CLIMATE-CHANGE; SURVIVAL; MOVEMENTS; Barrow's Goldeneye; Bucephala islandica; satellite telemetry; BRITISH-COLUMBIA; annual cycle; DISTANCE; latitude; phenology; PHILOPATRY; REMIGIAL MOLT; SONGBIRD; SWALLOWS; TRANSMITTERS

Selection of lake habitats by waterbirds in the boreal transition zone of northeastern Alberta - Found, C.; Webb, S. M.; Boyce, M. S. (Canadian Journal of Zoology, 2008)
We examined habitat characteristics associated with presence or absence of 16 waterbird species on 113 lakes during 2001-2006. We found that piscivorous species such as pelicans, loons, and mergansers were found on fish-bearing lakes, while birds that typically nest in emergent vegetation (e.g., coots, grebes) strongly preferred water bodies with moderate to high levels of emergent macrophytes. The presence of a riparian buffer was important for loons and several species of waterbird that nest on the backshore. Moderate to deep lake depth and high water clarity also were important for some species and likely associated with hunting habits and (or) fish availability. Breeding-occurrence models were developed for a few conspicuous species that could be sampled using aerial surveys. Surprisingly, changes in water levels were not important predictors for most species, and associations between waterbirds and high levels of recreational activity were unexpected. Common Loon (Gavia immer (Brunnich, 1764)) and Great Blue Heron (Ardea herodias L., 1758) were most sensitive to anthropogenic activities, with fewer of these species detected on lakes with more disturbed shorelines.
Keywords: Breeding Season; Common merganser; Mergus merganser; Habitat

Trends in the numbers of Coot Fulica atra and wildfowl Anatidae wintering in France, and their relationship with hunting activity at wetland sites - Fouque, Carol; Guillemain, Matthieu; Schricke, Vincent (Wildfowl, 2009)
Monitoring numbers of wintering wildfowl Anatidae and Coot Fulica atra is an important tool for their management and conservation. Twenty species of wildfowl and Coot have been counted monthly from December-February over 21 winters (1987-2008) at 88 French wetlands of national and international importance for these birds, covering 597 different count sites. Trends in average winter numbers were positive for 15 species, stable for Smew Mergus albellus, and indicated a decline in numbers for the five remaining species. Models assessing trends over time and also the effect of hunting status at the different sites (with sites grouped according to whether the area was hunted, partly hunted, or protected), found that bird numbers varied between sites of different status for A species except Red-crested Pochard Netta rufina. The immediacy with which hunting status affected local trends was less clear. There was no significant interaction between trends in numbers and the hunting status of the count sites for 10 of the 20 Anatidae species, including four of six species protected from hunting. For two protected species, trends were more favourable at fully hunted than at fully protected sites. Ten of the 14 quarry species did not show more favourable trends in protected than in hunted sites. Hunting activity at sites therefore does not, in itself, seem sufficient to explain differences in local trends in waterbird numbers.
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons

Status of the Harlequin Duck, Histrionicus histrionicus, in the western Northwest Territories - Fournier, Michael A.; Bromley, Robert G. (Canadian Field-Naturalist, 1996)
Details of historic and recent observations of the Harlequin Duck, Histrionicus histrionicus, in the western Northwest Territories including several possible breeding records are summarized. This evidence suggests a widely distributed population in the western Northwest Territories numbering in the hundreds of breeding pairs.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Harlequin duck; Histrionicus histrionicus

Effects of starvation on muscle and organ mass of King Eiders Somateria spectabilis and the ecological and management implications - Fournier, Michael A.; Hines, James E. (Wildfowl, 1994)
In the spring of 1990 we salvaged 21 carcasses of starved King Eiders from the Tuktoyaktuk and McKinley Bay areas of the Northwest Territories. The carcasses were dissected and muscle and organ mosses were measured for comparison with shot birds obtained from the Inuit hunters of Holman, N.W.T Most muscles and organs were significantly smaller in starved birds. The exception was the gizzard which was larger in starved birds. Average mass loss at death was approximately 45% of estimated initial body mass in males and 53% in females. This was reflected in the percent mass loss of individual muscles and organs. Starved females lost an estimated 4% more supracoracoideus mass, 4% more pectoralis mass, 5% more heart mass, 4% more gonad mass, 4% more liver mass, and 8%, more intestine length than starved males when compared to their shot counterparts. The amounts anti types of materials found in the gizzards of starved eiders varied considerably from that found in the gizzards of shot birds. Periods of starvation, either lethal or sublethal, during spring migration may have a severe impact on King Eider population dynamics.
Keywords: Nonbreeding Seasons; Migration; Physiology; King Eider; Somateria spectabilis; Energetics and Nutrition

Changed status of the Hooded Merganser, Lophodytes cucullatus, in the Yellowknife area, Northwest Territories - Fournier, Michael A.; Hines, James E. (Canadian Field-Naturalist, 1996)
Increased observations of Hooded Mergansers, Lophodytes cucullatus, have occurred in the Yellowknife area in recent years. These observations indicate that Hooded Mergansers now utilize this region during the post-breeding, moulting, and migration periods. The occurrence of paired birds in spring suggests the possibility of breeding. There are two plausible explanations for this increase, population increase and subsequent range expansion or displacement due to environmental disturbance.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Nonbreeding Seasons; Hooded Merganser; Lophodytes cucullatus

Persistence rates and detection probabilities of oiled king eider carcasses on St. Paul Island, Alaska - Fowler, Ada C.; Flint, Paul L. (Marine Pollution Bulletin, 1997)
Following an off spill off St Paul bland, Alaska in February 1996, persistence rates and detection probabilities of oiled king eider (Somateria spectabilis) carcasses were estimated using the Cormack-Jolly-Seber model. Carcass persistence rates varied by day, beach type and sex, while detection probabilities varied by day and beach type. Scavenging, wave action and weather influenced carcass persistence. The patterns of persistence differed on rock and sand beaches and female carcasses had a different persistence function than males. Weather, primarily snow storms, and degree of carcass scavenging, diminished carcass detectability. Detection probabilities on rock beaches were lower and more variable than on sand beaches. The combination of persistence rates and detection probabilities can be used to improve techniques of estimating total mortality.
Keywords: Nonbreeding Seasons; Contaminants; King Eider; Somateria spectabilis; Survival

Diet and habitat use of scoters Melanitta in the Western Palearctic - a brief overview - Fox, A. D. (Wildfowl, 2003)
If patterns of scoter distribution and abundance are to be understood, there is a need to know upon which prey items these birds feed, how they obtain these prey items and the habitats from which these food items are most easily harvested. Dietary studies and descriptions of habitats exploited by Common and Velvet Scoter in the non-breeding season are reviewed. The existing literature strongly suggests that, outside of the breeding season, these species forage mainly upon marine bivalve molluscs (especially those less than 4cm long) that live on the surface or within the upper 3cm of clean, coarse, sandy substrates in waters less than 20m deep. Although there is a large energetic cost to diving, handling and crushing such prey prior to digestion, such sedentary prey items often occur in very high densities, offering a locally abundant and predictable feeding resource. Since single species often dominate the diet, but dominant food items differ between feeding areas, it seems likely that scoters simply take whatever prey is locally available in sufficient abundance to fulfil nutritional needs. Large differences in documented prey size frequency distributions suggest that scoters may not select for specific prey size classes below an upper digestive limit. However, in the absence of any precise understanding of how scoters obtain their prey, nor any simultaneous studies of available benthic food abundance and size class distributions in scoter diets, it is not possible to confirm if differences simply reflect differences in profitability between different prey at different sites at different times of the year. There remains a considerable need to study the basic feeding ecology and the behaviour of scoters and their prey if their patterns of distribution and abundance are to be better understood.
Keywords: Melanitta fusca; Nonbreeding Seasons; White-winged Scoter; Trophic Interactions; Black Scoter; Melanitta nigra