Reproductive Strategy of Eider Ducks Somateria-Mollissima in Mixed Communities of Colonial Birds - Plyusnin Yu, M. (Izvestiya Sibirskogo Otdeleniya Akademii Nauk SSSR Seriya Biologicheskikh Nauk, 1982)
The reciprocal impacts of marine species of birds were studied in small nesting colonies. The nesting density of eider ducks is influenced by the size of herring and common gull colonies if the later are dominating the community. In the pure eider duck colonies, nesting density is the logistic function of colony size. The impact of the community on the success of eider ducks nesting and the survival of offspring is connected with the quantity of the dominating species: in great gull colonies the nesting density of eider ducks was .apprx. 0 and degenerated to diffusion settlings. The eider ducks reproductive strategy varies in different communities to minimize the unfavorable influence of the neighboring gull colonies on the reproductive potential of the population.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Productivity

Relatedness and the evolution of conspecific brood parasitism: parameterizing a model with data for a precocial species - Poeysae, Hannu (Animal Behaviour, 2004)
Conspecific brood parasitism (CBP) is a common reproductive tactic in several animal taxa, especially in precocial birds. It has been suggested that host-parasite relatedness can facilitate the evolution of CBP. A recent model showed that the existence and accuracy of the kin recognition system is crucial for this to occur. I used field data to parameterize the model for the common goldeneye, Bucephala clangula, a precocial species in which CBP frequently occurs and in which a recent finding of nonrandom host-parasite relatedness has been interpreted to support the idea that relatedness and kin selection influence CBP. It turned out that possibilities to detect brood parasitism and accurately discriminate between kin and nonkin parasites are negligible in the species. The empirically parameterized model exercise revealed that relatedness and kin selection are unlikely explanations of CBP in the species. Copyright 2004 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye

Public information and conspecific nest parasitism in goldeneyes: targeting safe nests by parasites - Poeysae, Hannu (Behavioral Ecology, 2006)
Conspecific nest parasitism (CNP) is a widespread alternative reproductive tactic in birds. Several hypotheses have been put forward to explain the evolution and occurrence of CNP, but no generally applicable hypothesis exists. Recent experimental results from the common goldeneye (Bucephala clangula), a cavity-nesting duck, have revealed that parasitic females preferentially lay eggs in safe nest-sites, implying that nest predation risk is an important ecological determinant of CNP. The present study focuses on the mechanisms by which parasites identify safe nest-sites. Predation risk of a given nest-site was predictable between successive breeding seasons. At the end of the nesting season, females prospected active nest-sites more frequently than nest-sites that did not have a nest in the current season. Nest-sites that had been prospected more frequently by females in year t had a higher probability to be parasitized in year t + 1. The results suggest that the use of public information, derived through nest-site prospecting, enabled parasites to target safe nests. These findings provide a new and potentially generally applicable perspective to understand the evolution and occurrence of CNP.
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye

Estimation of benthic macrofauna consumption by water birds in the bay of Saint-Brieuc (France) - Ponsero, A.; Le Mao, P. (Revue D Ecologie-La Terre Et La Vie, 2011)
Times Cited: 1 Ponsero, Alain Le Mao, Patrick 1
Keywords: Nonbreeding Seasons; Trophic Interactions; Sea Ducks

Associations between Resting, Activity, and Daily Metabolic Rate in Free-Living Endotherms: No Universal Rule in Birds and Mammals - Portugal, S. J.; Green, J. A.; Halsey, L. G.; Arnold, W.; Careau, V.; Dann, P.; Frappell, P. B.; Gremillet, D.; Handrich, Y.; Martin, G. R.; Ruf, T.; Guillemette, M. M.; et al. (Physiological and Biochemical Zoology, 2016)
Energy management models provide theories and predictions for how animals manage their energy budgets within their energetic constraints, in terms of their resting metabolic rate (RMR) and daily energy expenditure (DEE). Thus, uncovering what associations exist between DEE and RMR is key to testing these models. Accordingly, there is considerable interest in the relationship between DEE and RMR at both inter-and intraspecific levels. Interpretation of the evidence for particular energy management models is enhanced by also considering the energy spent specifically on costly activities (activity energy expenditure [AEE] = DEE 2 RMR). However, to date there have been few intraspecific studies investigating such patterns. Our aim was to determine whether there is a generality of intraspecific relationships among RMR, DEE, and AEE using long-term data sets for bird and mammal species. For mammals, we use minimum heart rate (f(H)), mean fH, and activity fH as qualitative proxies for RMR, DEE, and AEE, respectively. For the birds, we take advantage of calibration equations to convert fH into rate of oxygen consumption in order to provide quantitative proxies for RMR, DEE, and AEE. For all 11 species, the DEE proxy was significantly positively correlated with the RMR proxy. There was also evidence of a significant positive correlation between AEE and RMR in all four mammal species but only in some of the bird species. Our results indicate there is no universal rule for birds and mammals governing the relationships among RMR, AEE, and DEE. Furthermore, they suggest that birds tend to have a different strategy for managing their energy budgets from those of mammals and that there are also differences in strategy between bird species. Future work in laboratory settings or highly controlled field settings can tease out the environmental and physiological processes contributing to variation in energy management strategies exhibited by different species.
Portugal, Steven J. Green, Jonathan A. Halsey, Lewis G. Arnold, Walter Careau, Vincent Dann, Peter Frappell, Peter B. Gremillet, David Handrich, Yves Martin, Graham R. Ruf, Thomas Guillemette, Magella M. Butler, Patrick J.
Keywords: Common Eider; Somateria mollissima; Energetics and Nutrition

The use of body mass loss to estimate metabolic rate in birds - Portugal, Steven J.; Guillemette, Magella (Comparative Biochemistry and Physiology Part A Molecular & Integrative Physiology, 2011)
During starvation, energy production occurs at the expense of body reserve utilisation which results in body mass loss. Knowing the role of the fuels involved in this body mass loss, along with their energy density, can allow an energy equivalent of mass loss to be calculated. Therefore, it is possible to determine daily energy expenditure (DEE) if two body mass loss measurements at an interval of a few days are obtained. The technique can be cheap, minimally stressful for the animals involved, and the data relatively simple to gather. Here we review the use of body mass loss to estimate DEE in birds through critiquing the strengths and weaknesses of the technique, and detail the methodology and considerations that must be adhered to for accurate measures of DEE to be obtained. Owing to the biology of the species, the use of the technique has been used predominantly in Antarctic seabirds, particularly penguins and albatrosses. We demonstrate how reliable the technique can be in predicting DEE in a non-Antarctic species, common eiders (Somateria mollissima), the female of which undergoes a fasting period during incubation. We conclude that using daily body mass loss to estimate DEE can be a useful and effective approach provided that (1) the substrate being consumed during mass loss is known, (2) the kinetics of body mass loss are understood for the species in question and (3) only species that enter a full phase II of a fast (where substrate catabolism reaches a steady state) and are not feeding for a period of time are appropriate for this method. (C) 2010 Elsevier Inc. All rights reserved.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Physiology; Energetics and Nutrition

Do captive waterfowl alter their behaviour patterns during their flightless period of moult? - Portugal, Steven J.; Isaac, Rhian; Quinton, Kate L.; Reynolds, S. James (Journal of Ornithology, 2010)
Many different behavioural changes have been observed in wild waterfowl during the flightless stage of wing moult with birds frequently becoming inactive and reducing time spent foraging. Increased predation risk, elevated energetic demands of feather re-growth and restriction of foraging opportunities are thought to underlie these changes. By studying captive populations of both a dabbling and a diving duck species at the same site, we determined whether captive birds would reflect the behavioural responses of wild waterfowl to moult. The time-budgets of 42 Common Eiders, Somateria mollissima, (a diving duck) and 18 Garganeys, Anas querquedula, (a dabbling duck) were recorded during wing moult (July-August) and non-moult (January) with behaviour recorded under six categories. Despite captivity providing a low predation risk and constant access to food, birds altered their behaviour during the flightless period of wing moult. Time allocated to foraging and locomotion decreased significantly during moult compared to non-moult periods, while resting time increased significantly. Moulting Eiders underwent a greater reduction in time spent foraging and in locomotion compared with Garganeys, which is likely to be in response to a higher energetic cost of foraging in Eiders. It is possible that increased resting in both diving and dabbling ducks reduces their likelihood of detection by predators, while allowing them to remain vigilant. We demonstrate that there is much potential for using captive animals in studies that can augment our knowledge of behaviours of free-living conspecifics, the former being a hitherto under-exploited resource.
Keywords: Behavior; Common Eider; Nonbreeding Seasons; Molt; Somateria mollissima

King Eider (Somateria spectabilis) - Powell, Abby N. and Robert S. Suydam (The Birds of North America, 2012)
Keywords: King Eider; Somateria spectabilis

Variation in parental care of common goldeneye (Bucephala clangula) females - Poysa, Hannu (Behaviour, 1992)
Factors affecting the variation of parental care were examined in the precocial, nidifugous common goldeneye (Bucephala clangula), a species with uniparental female care. Parental care, measured as the time spent by the female in rearing the brood, varied considerably. Habitat shelterness and food abundance in brood rearing lakes did not affect the duration of parental care. Brood mortality and size affected females' decision to abandon the brood; broods left younger experienced higher mortality during the parental care and were smaller than broods reared for longer. Offspring left by a female did not have higher mortality than same-aged offspring not left. Broods that were deserted early did also produce young to the fledging age.
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye

Factors affecting abandonment and adoption of young in common eiders and other waterfowl: A comment - Poysa, Hannu (Canadian Journal of Zoology, 1995)
Factors affecting abandonment and adoption of young have been studied extensively in waterfowl. Several hypotheses have been advanced to account for these behaviors, and Bustnes and Erikstad (J.0. Bustnes and K.E. Erikstad. 1991. Can. J. Zool. 69: 1538-1545) recently evaluated these in common eiders (Somateria mollissima). They found, among other things, that young of "abandoners" had a lower survival rate than young of "tenders," but were not able to accurately time the mortality of ducklings. I propose a hypothesis based on brood success and parental investment theory to explain why some parents abandon their young exceptionally early and why some parents tend their own as well as foreign young. According to the hypothesis, parents provide relatively less care for offspring that are surviving less than average during the parental care period. The low survival of the young of abandoners while they are still with their own mother may have influenced the final decision of common eider females to abandon their broods early.
Keywords: Behavior; Breeding Season; Common Eider; Somateria mollissima

Population estimates and the timing of waterfowl censuses - Poysa, Hannu (Ornis Fennica, 1996)
The effect of the timing of waterfowl censuses on the estimates of breeding population sizes of different species was studied in southeast Finland from 1991 to 1994. Lakes used only for breeding and a local stop-over lake that was used for staging during spring migration were analysed separately. Also, the effect of the break-up of ice cover on the order of lake occupation by breeding pairs was studied. A standard waterfowl census was made four times in May at an interval of approximately seven days in each year. In general, the timing of waterfowl censuses within the three-week period considered did not cause serious biases in population estimates, though differences between species and between lake types were observed. The timing of the break-up of the ice cover was critical in the build-up of local breeding populations. However, pairs of many species, especially the Mallard, Teal, and Common Goldeneye occupied breeding lakes even when the lake still was considerably covered by ice. A comparison of recommended census times between earlier studies and this study suggests that in some species censuses could be started much earlier than previously recommended.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Bucephala clangula; Common Goldeneye; Techniques

Association between conspecific nest parasitism and the timing of breeding in the Common Goldeneye Bucephala clangula: An alternative interpretation - Poysa, Hannu (Ornis Fennica, 1999)
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye

Conspecific nest parasitism is associated with inequality in nest predation risk in the common goldeneye (Bucephala clangula) - Poysa, Hannu (Behavioral Ecology, 1999)
Previous studies of the role of nest predation in conspecific nest parasitism have not taken into account the possibility that predation risk may not be randomly distributed among nest sites and that breeding individuals may use different cues to assess the risk and adjust their reproductive tactic between years accordingly. Especially in cavity-nesting species, the role of nest predation in conspecific nest parasitism has been downplayed, while the role of nest site limitation has been highlighted. Using both observational and experimental data, I show that in the common goldeneye (Bucephala clangula), a cavity-nesting species in which conspecific nest parasitism is common, predation risk varies considerably between nest sites and does not follow a random expectation. The inequality in predation risk between nest sites also showed up in the occurrence of parasitized nests in an experimental setup. Nests parasitized in year t were more frequent in those nest sites that were not depredated during the previous nesting attempt in year t - n than in nest sites that were depredated and in control nest sites that had not been used for nesting before. A nest site addition experiment revealed that conspecific nest parasitism was not associated with nest site limitation. My findings give support for the hypothesis that nest predation is an important ecological factor explaining conspecific nest parasitism in goldeneyes.
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye

Parasitic common goldeneye (Bucephala clangula) females lay preferentially in safe neighbourhoods - Poysa, Hannu (Behavioral Ecology and Sociobiology, 2003)
Nest predation has been suggested as an explanation of the adaptive significance and evolution of conspecific brood parasitism, an alternative reproductive tactic pursued by females in several animal taxa. I used new nest boxes that contained only decoy eggs and were erected on lakes differing in real nest predation risk to test this hypothesis in the common goldeneye (Bucephala clangula), a hole-nesting duck. I used broken eggs to simulate predation risk of the boxes to determine if parasites having no previous experience with the boxes discriminate between seemingly safe and risky nest sites. Parasites laid eggs in the experimental boxes independently of the simulated predation risk, suggesting that they do not use broken eggs or nest disarray as indicators of predation intensity. Parasites preferred experimental boxes on lakes where real nest predation risk was low, supporting the nest predation risk hypothesis. Assuming that females in high risk areas have had experience of nest predation, they may take this into account in selecting host nests.
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye

Low host recognition tendency revealed by experimentally induced parasitic egg laying in the common goldeneye (Bucephala clangula) - Poysa, Hannu (Canadian Journal of Zoology, 2003)
Host-parasite relatedness has been suggested to promote the evolution of conspecific brood parasitism, an alternative reproductive tactic pursued by females in several animal taxa. An essential prerequisite for relatedness to promote brood parasitism is accurate kin recognition, including the recognition of related hosts by parasites. I performed a field experiment to address the accuracy of host recognition by parasites in the common goldeneye (Bucephala clangula), a cavity-nesting duck. I studied whether parasites discriminate between experimental nests that did not have a host (i.e., new nest boxes that contained chicken eggs dyed to mimic the colour of common goldeneye eggs) and real nests that did have a host (i.e., active nests that progressed to incubation). Parasitic egg laying in the experimental nests was not constrained by the lack of contemporarily available nests that had a host; it was also not constrained by the lack of suitable and empty nest sites. There was no difference in the start of parasitic laying between the experimental and real nests. The experimental nests and real nests were equally parasitized. The findings suggest that host recognition by parasites is not sophisticated in the common goldeneye, questioning the possible function of accurate kin recognition in brood parasitism in this species.
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye

Local variation in the timing and advancement of lake ice breakup and impacts on settling dynamics in a migratory waterbird - Poysa, H. (SCIENCE OF THE TOTAL ENVIRONMENT, 2022)
Timing of ice-out is important to fundamental hydrological and ecological processes in freshwater ecosystems at high northern latitudes. While earlier ice-out in lakes during the last century is a well-documented phenomenon across the Northern Hemisphere, local variation in the rate of advancement of ice-out has received little attention. Here, records of ice-out date in 1991-2020 from 37 small lakes in a boreal catchment area in southeastern Finland were used to study variation in the timing of ice-out and its advancement. In addition, data of settling phenology of migratory common goldeneyes (Bucephala clangula) at the study lakes were used to examine how betweenyear and within-season variation in the timing of ice-out affects lake settlement of the species. Overall, ice-out date (IOD, the timing of ice break-up in the spring) advanced 9.8 days during the 30-year study period, April temperature being more important than winter temperature (severity) in determining the IOD. Rate of the advancement of IOD in individual lakes varied from 1.5 to 16.1 days, having advanced more in relatively larger lakes. Lakes at higher elevations had later mean IOD than lakes at lower elevations. Within-season differences among the lakes in IOD increased from 1991 to 2020, this variation being mainly driven by temperature during the ice melting period. Lakes with late mean IOD were settled later in a season by breeding common goldeneyes than lakes with early IOD. The faster the ice melting progressed within a season, the faster common goldeneyes settled the breeding lakes. The results demonstrate how global warming differently affects IOD in boreal lakes even within the same catchment area. More research in the landscape context is needed to enhance our understanding of changes in IOD in boreal lakes and how differently advancing IOD affects local dynamics of species dependent on open water. (c) 2021 The Author. Published by Elsevier B.V. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/).
Times Cited in Web of Science Core Collection: 1 Total Times Cited: 1 Cited Reference Count: 109
Keywords: Climate change; CLIMATE-CHANGE; ECOLOGY; COVER; TEMPERATURE; PHENOLOGY; TRENDS; HABITAT SELECTION; Aquatic ecosystems; Catchment area; COMMON GOLDENEYE; Ice-out timing; MANN-KENDALL; NORTHERN-HEMISPHERE; Spring temperature

Do environmental conditions experienced in early life affect recruitment age and performance at first breeding in common goldeneye females? - Poysa, H.; Clark, R. G.; Paasivaara, A.; Runko, P. (JOURNAL OF AVIAN BIOLOGY, 2017)
Environmental conditions experienced early in life may have long-term impacts on life history traits and reproductive performance. We investigated whether ambient temperature experienced during the first two to four weeks of life and weather severity during the first two winters affected recruitment age and relative timing of breeding in the year of recruitment in female common goldeneyes Bucephala clangula. Our sample consisted of 141 female recruits hatched in a study population in central Finland between 1985 and 2013 and captured later as breeders. About 56% of the recruited females bred for the first time when two years old (range 2-6 yr). Individuals facing colder ambient temperatures during the first two to four weeks posthatch or more severe winter conditions during the first two winters did not recruit at an older age. Nor did maternal characteristics, relative hatch date or nest site availability affect recruitment age. For females that recruited at two years old, the date of first breeding was usually late relative to the population mean that year (mean difference 6.9 d, range -7 to 21 d). Our results suggest developmental buffering enables female goldeneye ducklings to mitigate the impacts of adverse environmental conditions experienced during the first weeks of life, at least in terms of first breeding.
Times Cited in Web of Science Core Collection: 1 Total Times Cited: 1 Cited Reference Count: 56
Keywords: BIRDS; DENSITY-DEPENDENCE; PATTERNS; BUCEPHALA-CLANGULA; SUCCESS; DUCKLINGS; GROWTH; REPRODUCTIVE-PERFORMANCE; FACTORS AFFECTING SURVIVAL; FITNESS CONSEQUENCES

Generalist predator, cyclic voles and cavity nests: testing the alternative prey hypothesis - Poysa, H.; Jalava, K.; Paasivaara, A. (OECOLOGIA, 2016)
The alternative prey hypothesis (APH) states that when the density of the main prey declines, generalist predators switch to alternative prey and vice versa, meaning that predation pressure on the alternative prey should be negatively correlated with the density of the main prey. We tested the APH in a system comprising one generalist predator (pine marten, Martes martes), cyclic main prey (microtine voles, Microtus agrestis and Myodes glareolus) and alternative prey (cavity nests of common goldeneye, Bucephala clangula); pine marten is an important predator of both voles and common goldeneye nests. Specifically, we studied whether annual predation rate of real common goldeneye nests and experimental nests is negatively associated with fluctuation in the density of voles in four study areas in southern Finland in 2000-2011. Both vole density and nest predation rate varied considerably between years in all study areas. However, we did not find support for the hypothesis that vole dynamics indirectly affects predation rate of cavity nests in the way predicted by the APH. On the contrary, the probability of predation increased with vole spring abundance for both real and experimental nests. Furthermore, a crash in vole abundance from previous autumn to spring did not increase the probability of predation of real nests, although it increased that of experimental nests. We suggest that learned predation by pine marten individuals, coupled with efficient search image for cavities, overrides possible indirect positive effects of high vole density on the alternative prey in our study system.
Times Cited in Web of Science Core Collection: 10 Total Times Cited: 10 Cited Reference Count: 63
Keywords: Bucephala clangula; DENSITY-DEPENDENCE; GOLDENEYE BUCEPHALA-CLANGULA; LONG-TERM; AEGOLIUS-FUNEREUS; MARTEN MARTES-MARTES; Martes martes; MEDIATED INTERACTIONS; Nest predation; RODENT ABUNDANCE; Search image; SEASONAL DIET; TERM POPULATION FLUCTUATIONS; Vole cycles; VULPES-VULPES

Estimating production in ducks: a comparison between ground surveys and unmanned aircraft surveys - Poysa, H.; Kotilainen, J.; Vaananen, V. M.; Kunnasranta, M. (EUROPEAN JOURNAL OF WILDLIFE RESEARCH, 2018)
We tested the use of unmanned aerial systems (UAS) in duck brood surveys in boreal wetlands in Finland. We performed brood surveys at the same wetlands concurrently with ground-based point counts and using a UAS (multicopter; drone counts) equipped with a camera that produced high-quality images for identification of broods and ducklings. The number of broods did not differ between point counts and drone counts in three duck species, the mallard (Anas platyrhynchos), common teal (Anas crecca), and common goldeneye (Bucephala clangula). The number of ducklings was higher in drone counts than in point counts in the common teal, but no such difference was found in the mallard and common goldeneye. UAS-based images seem to be useful for estimating numbers of both broods and ducklings for different duck species, although the manual processing of images is labor intensive.
Times Cited in Web of Science Core Collection: 19 Total Times Cited: 22 Cited Reference Count: 17
Keywords: Brood size; Drone; MALLARD DUCKLINGS; Multicopter; Species detection; Waterbird census

Reliability of egg morphology to detect conspecific brood parasitism in goldeneyes Bucephala clangula examined using protein fingerprinting - Poysa, Hannu; Lindblom, Kari; Rutila, Jarkko; Sorjonen, Jorma (Journal of Avian Biology, 2009)
Eadie (1989) developed a method based on variation between females in egg length, width and weight to detect conspecific brood parasitism in the field: using these three egg measures, Euclidean distance between all pairs of eggs within a clutch is calculated, and if maximum Euclidean distance (MED) between any two eggs exceeds a threshold value the nest is considered parasitized. The MED method has been tested in Finnish and Scottish common goldeneye Bucephala clangula populations but the results have been contradicting. Here we use protein fingerprinting to assess the validity of the MED method. Data comprised 35 clutches of which we knew, based on protein fingerprinting, how many different females laid the clutch (range 1-5 females). The mean MED of non-parasitized clutches (laid by 1 female only) was 1.470 (95% CI: lower 1.169, upper 1.771; n = 21) and that of parasitized clutches ( laid by 2 or more females) was 3.654 (95% CL: lower 3.083, upper 4.225; n = 14). Using a MED >3.0 as a criterion to identify parasitized clutches 89% of all clutches were classified correctly either parasitized or non-parasitized when compared to the identification based on protein fingerprinting. Clutch size and the number of females (beyond 2 females) did not affect the clutch MED, whereas the status of parasitism did. Repeatability of egg length, width and weight were: 0.63, 0.76 and 0.80, respectively, implying that, variation in these egg measures occurs among rather than within females. Our new results confirm that the MED method is reliable enough to detect parasitism in common goldeneye.
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye; Techniques

Response of parasitically laying goldeneyes to experimental nest predation - Poysa, Hannu; Lindblom, Kari; Rutila, Jarkko; Sorjonen, Jorma (Animal Behaviour, 2010)
Conspecific brood parasitism (CBP) has been identified as an integral life history component in birds. Recent empirical and theoretical studies suggest that nest predation is an important ecological factor affecting the occurrence and evolution of CBP; however, behavioural responses of parasites to nest predation remain unexplored. Here we report on a field experiment addressing the ability of parasitically laying common goldeneye, Bucephala clangula, females to respond to nest predation, based either on their own experience or on public information. Females that started parasitic laying in a nest and afterwards experienced partial clutch predation stopped laying in the nest. However, nests that faced partial clutch predation earlier in the season were not avoided by other parasitically laying females later in the season; these later-laying females had not themselves experienced the partial clutch predation in the nest. Hence, considering within-season responses to nest predation, a parasite uses its own experience, rather than public information, in laying decisions and nest choice. The rate of parasitic laying in the experimental nests decreased from the first to the last year of the experiment. Because the experimental nests never produced a successful clutch, this finding suggests that parasites used information on the ever-failing nature of the nests and avoided laying in them. Our results offer new experimental evidence to support the hypothesis that safety and success of nest sites play important roles in CBP. (C) 2010 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye

Nest-site selection in relation to habitat edge: Experiments in the Common Goldeneye - Poysa, Hannu; Milonoff, Markku; Ruusila, Vesa; Virtanen, Juha (Journal of Avian Biology, 1999)
Habitat edges affect several ecological phenomena, usually known as the edge-effect concept. One of its basic principles is the ecological trap hypothesis which assumes that birds are attracted to nest near habitat edges where food supplies may be greater but nest predation is higher. We studied nest-site selection in relation to the lake shore/forest habitat edge in the Common Goldeneye Bucephala clangula, a hole-nesting duck, using two types of experiment. First, we examined nest-site prospecting by erecting nest boxes with traps at the shoreline and inside the forest at varying distances from the shoreline. Secondly, we examined nest-site selection in three study areas by erecting nest boxes in pairs: at the shoreline and at varying distances inside the forest. In addition we experimentally measured nest predation rate in shore and forest boxes using artificial nests. Goldeneye females prospected shore and forest boxes equally. However, the final decision was in favour of shore boxes: within a box pair, the shore box was occupied first in all three study areas. There was no difference in nest predation rate between shore and forest boxes, except in one study area where predation rate was lower, not higher, in shore boxes. Thus, while Goldeneye females clearly exhibit a pattern of nest-site selection in relation to habitat edge, the ecological trap hypothesis is not supported so far as the risk of predation is considered. Increased predation risk associated with the period of getting hatched young out of the nest to a brood-rearing lake may be the reason for the rejection of forest boxes.
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Habitat

Nest predation in hole-nesting birds in relation to habitat edge: An experiment - Poysa, Hannu; Milonoff, Markku; Virtanen, Juha (Ecography, 1997)
We experimentally tested the hypothesis that nest predation rate in hole-nesting birds, especially the common goldeneye Buccephala clangula, was related to the edge between aquatic and terrestrial habitats. We also studied whether nest predation rate was related to habitat patch (lake) size. In three Study areas nest-boxes were erected in pairs: one nest-box was erected at the shoreline and the other one inside the forest at a varying distance (range from 14 to 140 m) from the shoreline. One chicken egg was placed in each nest-box (dummy nest). Overall predation rate on dummy nests varied from 34.6% to 52.6% depending on the study area. The pine marten Martes martes was the primary nest predator in all study areas. Daily predation rates did not differ between natural and dummy nests. Predation rate on dummy nests was not related to the distance of the nest-box from the shoreline in any study area. Predation rate was not related to lake size in two study areas but in one area predation rate on dummy nests was lower around largest lakes. However, the result may be accidental and not because of lake size per se because the proportion of forest was exceptionally low in that part of the study area.
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Productivity; Habitat

Movements and mortality of common goldeneye Bucephala clangula broods in a patchy environment - Poysa, Hannu; Paasivaara, Antti (Oikos, 2006)
Effects of habitat configuration on movements, space use, and mortality of individuals are crucial for our understanding of the dynamics and persistence of populations in patchy environments. We studied these aspects in a naturally patchy environment using radio-marked common goldeneye (Bucephala clangula) females with their broods. The landscape consisted of suitable patches (lakes) and definitely inhospitable matrix (all terrestrial habitat surrounding the lakes), many of the patches being connected with corridors of varying usability (semipermanent and permanent ditches). We focused on habitat-related factors potentially affecting the decision of common goldeneye females and broods to leave the hatching patch, the rate of movement within the landscape, and the first-week mortality of ducklings when moving within the landscape. The probability to leave the hatching patch was high if the number of neighbouring patches was high, whereas mean distance to neighbouring patches and the presence and usability of corridors did not affect the probability to leave the hatching patch. Different measures of distance moved (i.e. within patches, through corridors, through matrix) were not strongly associated with any of the variables measuring habitat configuration. Corridors were used when available, but the broods also frequently moved through the matrix. There was no significant difference in the daily mortality rate of ducklings between broods that stayed in the hatching patch and broods that left the hatching patch. Among the broods that left the hatching patch, high daily mortality rate was associated with the lack and low usability of corridors. Daily mortality rate of ducklings was not associated with the distance moved through the matrix, nor with the other measures of distance moved or the variables measuring habitat configuration. Our findings suggest that species living in naturally patchy environments may have evolved remarkable skills to successfully cross an inhospitable matrix when changing patches.
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Dispersal; Survival; Habitat

Nest predation risk, but not demography, drives dynamics of conspecific brood parasitism - Poysa, H.; Paasivaara, A. (Behavioral Ecology, 2016)
Conspecific brood parasitism (CBP) is an alternative reproductive tactic in several animal taxa. Although various behavioral aspects related to CBP have been studied in several species, understanding spatial and temporal dynamics of CBP and its drivers is still limited. We studied roles of nest predation risk and demography as possible drivers of dynamics of CBP in common goldeneyes (Bucephala clangula), a cavity-nesting duck. We provided decoy nests for parasitic laying in an experimental setting of 15 lakes for 7 consecutive years irrespective of local nest predation, being thus able to control for effects of predation-determined host nest availability. Individual parasites were recognized using protein fingerprints from egg albumen of parasitic eggs laid in the decoy nests. We found considerable spatial and temporal variation in the frequency of CBP within the experimental setting. Variation in CBP was driven by nest predation risk: the rate of CBP tracked the number of nonpredated nesting attempts at the lakes during the previous year. Neither variation in lake-specific number of potential homing first-time breeding females (i.e., demography) nor variation in lake-specific number of nesting females present explained the variation in lake-specific frequency of CBP. Our findings provide evidence that parasitically laying females pursue a genuine and flexible safety-seeking tactic in nest selection and that nest predation risk drives spatial and temporal dynamics of CBP.
Poysa, Hannu Paasivaara, Antti
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye

Co-parasites preferentially lay with kin and in safe neighbourhoods: experimental evidence from goldeneye ducks - Poysa, H.; Paasivaara, A.; Lindblom, K.; Rutila, J.; Sorjonen, J. (Animal Behaviour, 2014)
Conspecific brood parasitism (CBP) is an alternative reproductive tactic in several animal taxa. Recently the role of kinship in CBP has been in focus, and some studies have demonstrated high host-parasite relatedness in avian CBP systems. However, high natal and breeding site fidelity of hosts and parasites complicates the interpretation of previous observational findings, and the mechanisms leading to high host-parasite relatedness remain unknown. Some recent findings suggest that broadening the scope of the study of interactions may cast light on these mechanisms. We studied relatedness between parasites laying in the same nest (co-parasites) and factors possibly driving relatedness patterns between co-parasites in the common goldeneye, Bucephala clangula. Based on a field experiment, controlling for site fidelity and host role, we report here that both relatedness and safety of the nest site, and their interaction, affected the likelihood of two females engaging in co-parasitism. At the population level, parasites indeed seemed to lay eggs preferentially with kin. Analyses at a finer spatial scale revealed that high relatedness between co-parasites was not due to the philopatry effect only. Parasites engaging in co-parasitism also laid in safer neighbourhoods than parasites that did not engage in co-parasitism; the number of nondepredated nesting attempts the previous year was higher for the parasites engaging in co-parasitism. However, the interaction between relatedness and safety of the nest site suggests that co-parasitism at dangerous lakes was more likely to involve relatives. Our results provide the first experimental evidence that nest predation risk and interaction between related parasites are associated with kin-biased co-parasitism in a CBP system. (C) 2014 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.
Poysa, Hannu Paasivaara, Antti Lindblom, Kari Rutila, Jarkko Sorjonen, Jorma
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye

Nest predation and the evolution of conspecific brood parasitism: From risk spreading to risk assessment - Poysa, Hannu; Pesonen, Mauri (American Naturalist, 2007)
Conspecific brood parasitism (CBP) is a taxonomically widespread reproductive tactic. One of the earliest hypotheses put forward to explain the evolution of CBP was "risk spreading"; that is, by laying eggs in more than one nest, parasites may increase the likelihood that at least one offspring will survive to independence. However, the risk spreading hypothesis, based on the assumptions of random nest predation and random selection of target nests by parasites, was theoretically refuted soon after its appearance. New results from the common goldeneye (Bucephala clangula) have revealed that nests are not predated at random and that parasites preferentially lay in safe nests. By taking into account these findings and by modifying accordingly the basic assumptions of the earlier model that refuted the risk spreading hypothesis, we built a model to address the role of nest predation in the evolution of CBP. Model simulations revealed that the selective advantage of parasitic laying, related to nest predation, is much higher than previously thought. Furthermore, the invasion probability of parasitic tactic when initially rare was reasonably high within our model framework. We show that the use of risk assessing, instead of random risk spreading, makes parasitic laying evolutionarily advantageous.
Keywords: Behavior; Breeding Season; Sea Ducks - General; Bucephala clangula; Common Goldeneye

Nest-site limitation and density dependence of reproductive output in the common goldeneye Bucephala clangula: Implications for the management of cavity-nesting birds - Poysa, H.; Poysa, S. (Journal of Applied Ecology, 2002)
1. Hole-nesting birds are frequently faced with a shortage of suitable nest sites in regions of intensive forest management. Nest boxes are sometimes provided to alleviate nest-site limitation in cavity-nesting waterfowl and are also recommended for several rare and endangered species. However, the impacts on effective breeding numbers and breeding success have rarely been considered, particularly in instances where density dependence might operate. 2. We experimentally manipulated nest sites to assess limits on the population size of a secondary cavity-nesting species, the common goldeneye Bucephala clangula, living on freshwater lakes. We also examined density dependence in their reproductive output. 3. Breeding pairs were counted in experimental and control areas over a 12-year period; for 4 years (1988-91) before nest box addition (1992-94 in the experimental area) and for 5 years (1995-99) afterwards. Broods were counted each year between 1988 and 1999 to study reproductive output. 4. Mean number of pairs per lake increased after the addition of nest boxes in the experimental area but not in the control area. However, neither the mean number of broods per lake nor the mean number of fledged birds per lake increased significantly in the experimental area. 5. When the whole period of 1988-99 was considered and data pooled from all the lakes, the numbers of broods and fledged birds showed negative density dependence of reproductive output. 6. Our results indicate that nest sites limit the population size of breeding common goldeneye, but show also that density-dependent factors operate to limit reproductive output. The possibility that density dependence may negate management actions directed at increasing breeding numbers in cavity-nesting waterfowl should be considered carefully before taking these actions. This also applies to nest box provisioning programmes aiming to manage populations of endangered species.
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Population Dynamics; Habitat

Acidification and ecological interactions at higher trophic levels in small forest lakes: The perch and the common goldeneye - Poysa, Hannu; Rask, Martti; Nummi, Petri (Annales Zoologici Fennici, 1994)
The disappearance of acid sensitive fish species that usually are the most important top predators in freshwater ecosystems is an important ecological consequence of lake acidification. This may have beneficial consequences for insectivorous waterbirds that may compete for food with fish. We studied the response of common goldeneye (Bucephala clangula) pairs and broods to pH, perch (Perca fluviatilis) density and invertebrate abundance in small forest lakes in southern Finland. Neither the density of breeding pairs nor that of broods showed an overall trend with lake acidity but both of them increased with invertebrate abundance. Among three lakes studied in more detail for several years both pair density and brood density were highest in the lake with lowest pH and perch density and highest invertebrate abundance. Goldeneye brood density, but not pair density, increased after a sudden perch death in an experimental lake. Our results indicate that both breeding pairs and broods of goldeneyes may benefit of acidity-induced release in food competition after the disappearance of fish competitors.
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Contaminants; Population Dynamics; Trophic Interactions

The importance of hunting pressure, habitat preference and life history for population trends of breeding waterbirds in Finland - Poysa, H.; Rintala, J.; Lehikoinen, A.; Vaisanen, R. A. (European Journal of Wildlife Research, 2013)
Times Cited: 1 Poysa, Hannu Rintala, Jukka Lehikoinen, Aleksi Vaisanen, Risto A. 1
Keywords: Conservation; Breeding Season; Abundance, Distribution, and Trends; Sea Ducks

Natal philopatry and the local resource competition hypothesis: Data from the common goldeneye - Poysa, H.; Runko, P.; Ruusila, V. (Journal of Avian Biology, 1997)
Sex-biased local resource competition (LRC) between parents and offspring has been suggested to exert selection pressure on progeny sex ratio variation in birds. In a recent article Weatherhead and Montgomerie (1995) questioned that the assumptions underlying the LRC hypothesis are applicable to birds. We here study the basic assumptions of the LRC hypothesis with data from the Common Goldeneye Bucephala clangula. First, we found strong female-biased natal philopatry, as expected in Anseriformes. Second, of all the females breeding in the study area, individuals born there comprised a major proportion each year. Third, we document a considerable overlap between home ranges of breeding mothers and daughters. Our results, combined with results from other Common Goldeneye populations and other Bucephala species, give strong support for the assumptions of the LRC hypothesis to be applicable to birds, at least to some species.
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Dispersal

Identification of parasitized nests by using egg morphology in the Common Goldeneye: An alternative to blood sampling - Poysa, Hannu; Runko, Pentti; Ruusila, Vesa; Milonoff, Markku (Journal of Avian Biology, 2001)
We used data from three Common Goldeneye Bucephala clangula populations in Finland to study if the variation between females in egg morphology, as measured using a method developed by Eadie (1989), can be used to identify parasitized clutches. Eadie's method is based on z-score standardized measures of length, width, and weight of eggs. Using these measures, Euclidean distance for each pair of eggs within a clutch was calculated. Euclidean distance between the two most dissimilar eggs (maximum Euclidean distance, MED) was used as the criterion to identify parasitized clutches. Test clutches of 3 eggs that included one egg from each of three different females had a higher MED (2.80) than 3-egg clutches that included eggs from one female only (2.05), proving that there is statistically significant variation in egg morphology between females. Test clutches that included three eggs from each of three different females (9 eggs in all) had a mean MED of 4.51. The mean MED of naturally parasitized clutches (4.83) was higher than that of nonparasitized clutches (2.12). Further analyses suggested that MED > 3.0 can be used as a conservative and reliable criterion to identify parasitized clutches. Our results confirm that Eadie's method is reliable enough to identify parasitized clutches in Common Goldeneyes.
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Techniques

Ability to assess nest predation risk in secondary hole-nesting birds: An experimental study - Poysa, Hannu; Ruusila, Vesa; Milonoff, Markku; Virtanen, Juha (Oecologia (Berlin), 2001)
Because nest predation is the major source of nesting mortality in birds, site-specific predation risk may play an important role in determining birds' ability to select nest sites that reduce predation risk. This possibility has not been adequately tested. Here we report on 5-year experiments by which we studied, independently from birds' earlier experience with specific nest boxes, both the selection and predation risk of nest sites in the common goldeneye (Bucephala clangula). New, previously unoccupied nest boxes were erected in two habitat types on three study areas. Experimentally measured predation risk in the nest boxes varied between 0 and 1.0, i.e. goldeneye females could select a nest site along a wide gradient of possible predation-risk values. We did not find a difference in predation risk between occupied and unoccupied nest boxes, nor was the order of nest box occupation associated with predation risk. A power analysis revealed that our test had reasonably high power to reject a false null hypothesis. Our results suggest that common goldeneye females likely have not evolved an ability to assess predation risk of new, previously unoccupied nest sites.
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye

Habitat selection and survival of common goldeneye (Bucephala clangula) broods: preliminary results - Poysa, Hannu; Virtanen, Juha (Hydrobiologia, 1994)
Factors affecting habitat selection and survival of individual Common Goldeneye (Bucephala clangula) broods were studied. Females were marked with radio transmitters and coloured wing tags, and their movements and that of their broods were followed to investigate the pattern of lake use. Broods frequently left hatching lakes and moved varying distances and made overland travels to reach actual brood rearing lakes. Food was more abundant and pH lower in rearing lakes compared with hatching lakes. Rearing lakes also were smaller and more isolated than hatching lakes but did not differ with respect to the structure of shore vegetation. Mortality rate varied considerably between broods. However, total distance moved and the length of overland travel was not associated with increased duckling mortality. Neither was mortality associated with the size, isolation or vegetation structure of the rearing lakes.
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Dispersal; Survival; Habitat

Common goldeneyes adjust maternal effort in relation to prior brood success and not current brood size - Poysa, Hannu; Virtanen, Juha; Milonoff, Markku (Behavioral Ecology and Sociobiology, 1997)
Parental investment theory predicts that parental effort should be related to the reproductive value of the current brood. This depends on both the number of young and the survival prospects of each of them. Thus parents may provide more care to larger broods either because of (1) the direct effect of brood size per se on reproductive value (the "brood size" hypothesis) or because (2) past mortality, reflected in current brood size, predicts future mortality of the brood and hence its reproductive value (the "brood success" hypothesis). Earlier studies have not attempted to distinguish between these alternatives. We tested the hypotheses in the precocial, nidifugous common goldeneye Bucephala clangula, a species with uniparental female care. Maternal effort was measured as the time spent by the female in rearing the brood. We found that brood size itself is not associated with maternal effort, but that females modify their maternal effort according to the mortality already experienced by the brood, supporting the prediction of the brood success hypothesis. We also found that brood mortality varied considerably between broods and that previous mortality predicts future mortality within broods, basic assumptions of the brood success hypothesis.
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye

Nesting of the Common Eider near the Hell Gate-Cardigan Strait Polynya Canada 1980-81 - Prach, R. W.; Smith, A. R.; Dzubin, A. (Reed, A. (Ed.). Canadian Wildlife Service Report Series, No. 47. Eider Ducks in Canada. V+177p. Canadian Wildlife Service: Ste-Foy, Quebec, Canada. Illus. Maps. Paper, 1987)
Keywords: Breeding Season; Common Eider; Somateria mollissima; Productivity

Trace elements in eggs of common eiders (Somateria mollissima) breeding in Nova Scotia, Canada - Pratte, I.; Tomlik, M. D.; Betsch, T. A.; Braune, B. M.; Milton, G. R.; Mallory, M. L. (Marine Pollution Bulletin, 2015)
We provide the first report on trace element concentrations in eggs of common eiders (Somateria mollissima), a coastal benthic foraging sea duck, from Nova Scotia, Canada, and compare those to known values from this species elsewhere. Most trace elements of toxicological concern (Hg, Se, Cd, Cu, Zn) were lower in eider eggs from Nova Scotia than from eider eggs collected farther north in Canada, although As was elevated. Our data provide strong support for a pattern of increasing Hg at higher latitudes for this species. (C) 2015 Elsevier Ltd. All rights reserved.
Pratte, Isabeau Tomlik, Molly D. Betsch, Taylor A. Braune, Birgit M. Milton, G. Randy Mallory, Mark L.
Keywords: Breeding Season; Common Eider; Contaminants; Somateria mollissima

Summer Distribution and Population Size of the King Eider Somateria-Spectabilis in Svalbard Arctic Ocean - Prestrud, P. (Norsk Polarinstitutt Skrifter, 1991)
Registrations of King Eiders were made throughout Svalbard in the period 1982-1985. In addition, records of casual observations of King Eiders in the period 1970-1985 were collected in a fauna database. The most important breeding grounds were found between Bellsund and Isfjorden. Moulting takes place along the western coast of Spitsbergen in July-August, and large flocks are found at the outlet of Isfjorden, in Bellsund, and between Hornsund and Sorkapp, at this time of the year. The minimum and maximum population size in August is estimated at about 2,500 and 4,000-5,000 individuals respectively.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Nonbreeding Seasons; Molt; King Eider; Somateria spectabilis

Population Size and Summer Distribution of the Common Eider Somateria-Mollissima in Svalbard Arctic Ocean 1981-1985 - Prestrud, P.; Mehlum, F. (Norsk Polarinstitutt Skrifter, 1991)
The most important breeding localities of the Common Eider in Svalbard are mapped on the basis of surveys made during the five summer seasons 1981-1985. The breeding populations along the western and eastern coasts are estimated to be 12,000-17,000 and 1,500-3,500 pairs respectively. The most important moulting areas are found along the western coast of Spitsbergen, particularly along the western coast of Prins Karls Forland and Nordenskioldkysten. There have been no significant increases in the breeding population since the establishment of the bird sancturaries in 1973. The total late summer population is estimated to be 80,000-140,000 individuals. The population at the turn of the century was probably more, but not as much as 10 times larger as stated in earlier publications.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Common Eider; Somateria mollissima

Acanthocephalan parasites of waterbirds in Eastern Washington - Priebe, Margaret D. (Trans Amer Microsc Soc, 1952)
In an examination of 199 waterbirds for the presence of Acanthocephala, 42 birds, including 16 spp., were found infected. New hosts for Acanthocephala were the Holboell Grebe, the Black Crowned Night Heron and the Caspian Tern. The presence of the Acanthocephalans Corynosoma constrictum in the Bufflehead and Polymorphus trochus in the Common Mallard has not been previously noted. Pathological examination of infected birds demonstrated that heavy infections can cause losses of birds due to inflammatory reaction and fibrosis in the intestinal wall, whereas light infections produce little change in the intestinal mucosa. || ABSTRACT AUTHORS: M. D. Priebe
Keywords: Bucephala albeola; Bufflehead; Parasites

Nest sites used by wood ducks and common goldeneyes in New Brunswick - Prince, Harold H. (J Wildl Manage, 1968)
Silver maple (Acer saccharinum) and elm (Ulmus americana) are dominant tree species in the floodplain forest along the St. John River in central New Brunswick. In the continuous forest there were 5. 5 "good" duck nest cavities per hectare (2. 47 acres). Silver maples or elms growing on marginal sites were more likely to contain a suitable nesting cavity. For all tree species around active duck nest sites, the total density and dominance values were 19 to 32[degree]/o of the values in the nearby forest, suggesting that for ducks to use the area the forest around cavities must be relatively open. Around the sites of 24 wood duck (Aix sponsa) and 16 goldeneye (Bucephala clangula) nests, the trees numbered about the same, but they were larger at wood duck sites. Very little competition for nest sites was observed between wood ducks and goldeneyes; they appeared to use different forest areas. The nest cavities used by goldeneyes varied less in dimension than those used by wood ducks, even though the same variety was available to each species. Cavity diameter seemed important in goldeneye nest selection. The few black duck (Anas rubripes) cavities differed from those of wood ducks and goldeneyes in being open and shallow. || ABSTRACT AUTHORS: Author
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Habitat

Color Atlas of Wildlife Pathology Part 2 Duck Plague in Free Flying Waterfowl Observed During the Lake Andes Epizootic - Proctor, S. J.; Pearson, G. L.; Liebovitz, L. (Wildlife Diseases, 1975)
The 1st major epizootic of duck plague in free-flying waterfowl occurred at Lake Andes, South Dakota [USA], in January and February 1973. Duck plague was diagnosed in black ducks, mallards, pintail-mallard hybrids, redheads, common mergansers, common golden eyes, canvasbacks, American widgeon, wood ducks and Canada geese, indicating the general susceptibility of ducks to duck plague. Clincial signs observed in mallards were droopiness, polydipsia lethargy, reduced wariness, weakness, reluctance to fly, swimming in circles, bloody diarrhea, bloody fluid draining from the nares and bill and terminal convulsions. Because the mallard was the most numerous and heavily infected species during the Lake Andes epizootic, gross and microscopic lesions of the gastrointestinal tract, liver, spleen, thymus, bursa of Fabricius, heart, lung, bone marrow, pancreas and ovaries were described. Lesions of the esophagus and cloaca were seen in the stratified squamous epithelium, submucosal lymphoid nodules and esophageal submucosal glands. In the small and large intestine, lesions were located in lymphocytic aggregates, lamina propria and crypt epithelium. Hemorrhages and necrosis of hepatocytes and bile duct epithelium were noted in the liver. Hemorrhages in other tissues, i.e., the lung and heart, were often associated with lymphoid nodules while those in organs such as the pancreas were associated with acinar necrosis. Intranuclear inclusion bodies were seen in stratified squamous epithelium of the esophagus and cloaca, crypt epithelium of the intestine, hepatocytes, bile duct epithelium, cells of Hassel's corpuscles, splenic periarteriolar reticular cells and epithelial cells in the bursa of Fabricius.
Keywords: Sea Ducks - General; Nonbreeding Seasons; Disease; Common merganser

Implications of mercury and lead concentrations on breeding physiology and phenology in an Arctic bird - Provencher, J. F.; Forbes, M. R.; Hennin, H. L.; Love, O. P.; Braune, B. M.; Mallory, M. L.; Gilchrist, H. G. (ENVIRONMENTAL POLLUTION, 2016)
Although physiological traits and phenology are thought to be evolved traits, they often show marked variation within populations, which may be related to extrinsic factors. For example, trace elements such as mercury (Hg) and lead (Pb) alter biochemical processes within wildlife that may affect migration and breeding. While there is a growing understanding of how contaminants may influence wildlife physiology, studies addressing these interactions in free-living species are still limited. We examined how four non-essential trace elements (cadmium, Hg, Pb and selenium) interacted with physiological and breeding measures known to influence breeding in a free-living population of common eider ducks (Somateria mollissima). We collected blood from female eiders as they arrived at a breeding colony in northern Canada. Blood was subsequently assessed for baseline corticosterone (CORT), immunoglobulin Y (IgY), and the four trace elements. We used model selection to identify which elements varied most with CORT, IgY, arrival condition, and arrival timing. We then used path analysis to assess how the top two elements from the model selection process (Hg and Pb) varied with metrics known to influence reproduction. We found that arrival date, blood Hg, CORT, and IgY showed significant inter-annual variation. While blood Pb concentrations were low, blood Pb levels significantly increased with later arrival date of the birds, and varied negatively with eider body condition, suggesting that even at low blood concentrations, Pb may be related to lower investment in reproduction in eiders. In contrast, blood Hg concentrations were positively correlated with eider body condition, indicating that fatter birds also had higher Hg burdens. Overall, our results suggest that although blood Hg and Pb concentrations were below no-effect levels, these low level concentrations of known toxic metals show significant relationships with breeding onset and condition in female eider ducks, factors that could influence reproductive success in this species. Crown Copyright (C) 2016 Published by Elsevier Ltd. All rights reserved.
Times Cited in Web of Science Core Collection: 47 Total Times Cited: 47 Cited Reference Count: 91
Keywords: EIDERS SOMATERIA-MOLLISSIMA; Arctic; PERSISTENT ORGANIC POLLUTANTS; Marine birds; BODY CONDITION; NESTING COMMON EIDERS; IMMUNE FUNCTION; Cumulative effects; Endocrine system; Hormones; Immunity; KESTRELS FALCO-SPARVERIUS; KITTIWAKES RISSA-TRIDACTYLA; LONG-LIVED SEABIRD; REPRODUCTIVE INVESTMENT; SCAUP AYTHYA-AFFINIS

Anti-parasite treatment, but not mercury burdens, influence nesting propensity dependent on arrival time or body condition in a marine bird - Provencher, J. F.; Forbes, M. R.; Mallory, M. L.; Wilson, S.; Gilchrist, H. G. (SCIENCE OF THE TOTAL ENVIRONMENT, 2017)
Arctic wildlife can be exposed to high mercury (Hg) levels, and are also naturally exposed to gastrointestinal parasites that can reduce condition and negatively affect reproductive output and/or survival in similar ways. Importantly, both Hg and parasites are increasing in wildlife in some Arctic regions. We studied the northern common eider duck (Somateria mollissima) to explore how Hg in association with both natural levels and experimentally reduced parasitic infections, affect reproduction and survival. Female eiders were measured, banded, and blood sampled to determine blood Hg burdens, prior to breeding. Propensity to nest, clutch size, nest survival, nest attendance, and return rates were assessed in relation to both Hg burden and parasite treatment. Neither reproduction nor return rates of females varied with Hg concentrations, but females arriving late to the colony, or in low body condition, showed increased nesting propensity when given the anti-parasite treatment as compared to placebo treatment. Our results suggest that parasites can play a critical role in decisions to invest in avian breeding annually, particularly among individuals with a late onset to breeding, and in poor condition. Crown Copyright (C) 2016 Published by Elsevier B.V. All rights reserved.
Times Cited in Web of Science Core Collection: 16 Total Times Cited: 18 Cited Reference Count: 65
Keywords: Contaminants; SURVIVAL; Arctic; COMMON EIDER DUCKS; REPRODUCTION; SELENIUM; Bird; INDIVIDUAL OPTIMIZATION; BLOOD; CADMIUM; LONG-LIVED BIRD; FENBENDAZOLE; Breeding decisions; Nesting; PARASITES; Parasitism

Direct and indirect causes of sex differences in mercury concentrations and parasitic infections in a marine bird - Provencher, J. F.; Gilchrist, H. G.; Mallory, M. L.; Mitchell, G. W.; Forbes, M. R. (Science of the Total Environment, 2016)
In many animal species, males and females differ in their levels of contaminants and/or parasitic infections. Most contaminants and gastro-intestinal parasites are obtained through prey ingestion, and thus the causes of sex differences in the distribution of these factors might follow similar pathways. We studied the northern common eider duck (Somateria molissima borealis) as an avian model, and used directed separation path analysis to explore the causes of sex differences in mercury (Hg) and gastro-intestinal helminths. Two trophically transmitted helminths were examined: a cestode (Lateriporus sp.) and an acanthocephalan (Polymorphus sp). We found that the number of Lateriporus sp. varied positively with stable isotope signature (as indicated by delta N-15 in eider breast muscle tissue), and negatively with crustaceans being present in the short term diet. We also found that Polymorphus sp. varied positively with eider tissue stable isotope signature. However, Polymorphus sp. varied negatively with sex indirectly through condition and liver mass. Similarly, Hg concentrations also varied negatively with sex indirectly through condition and liver mass, with both Polymorphus sp. intensity and Hg concentrations significantly higher in males. We found that model fit increased when a negative relationship between the two helminth species was included, suggesting a yet unknown causal mechanism linking these parasites. Our findings suggest that although Hg and gastro-intestinal parasites are both trophically transmitted through the eider's prey items, the factors that contribute towards bioaccumulation of these two burdens differ in source, likely caused by several different factors and may potentially influence each other. (C) 2016 Elsevier B.V. All rights reserved.
Provencher, J. F. Gilchrist, H. G. Mallory, M. L. Mitchell, G. W. Forbes, M. R.
Keywords: Common Eider; Contaminants; Somateria mollissima; Parasites

Breeding biology of Steller's eiders (Polysticta stelleri) near Barrow, Alaska, 1991 - 99 - Quakenbush, Lori; Suydam, Robert; Obritschkewitsch, Tim; Deering, Michele (Arctic, 2004)
The breeding biology of Steller's Ciders (Polysticta stelleri) near Barrow, Alaska, was studied from 1991 to 1999. The number of nests found per year ranged from 0 to 78. Mean clutch size was 5.4 (SD = 1.6, n = 5 1), incubation period was 24 days, and Mayfield nest success ranged from 0 to 35%. Egg survival was 24% overall (n = 45 1). Most nests were found on the rims of low-centered polygons near ponds with emergent vegetation. Marked broods remained within 700 rn of their nest sites, and duckling survival was low. Steller's ciders nested in five of the nine years studied, corresponding with years of high lemming density and nesting pomarin jaegers (Stercorarius pomarinus) and snowy owls (Bubo scandiacus). Steller's eiders may choose to nest only in years with abundant lemmings for two reasons: first, abundant lemmings provide an alternative prey source for foxes and other predators of ciders; second, jaegers and owls defending their own nests may inadvertently provide protection to ciders nesting nearby.
Keywords: Breeding Season; Productivity; Habitat; Polysticta stelleri; Steller's eider

Historical and present breeding season distribution of Steller's Eiders in Alaska - Quakenbush, Lori T.; Day, Robert H.; Anderson, Betty A.; Pitelka, Frank A.; McCaffery, Brian J. (Western Birds, 2002)
The Alaska breeding population of the Steller's Eider (Polysticta stelleri) occurs as two subpopulations, one on the Arctic coastal plain of northern Alaska, primarily near Barrow, and the other on the Yukon-Kuskokwim Delta of western Alaska. In 1997, the Alaska breeding population was listed under the Endangered Species Act as threatened because the nesting range and population were thought to have decreased substantially. The historical (pre-1970) and recent (1970-present) breeding distribution and abundance of Steller's Eiders, however, are not well known. We compiled and evaluated the historical and recent records of breeding-season distribution, confirmed nesting for northern and western Alaska, and found that the overall sizes of the breeding ranges have not changed substantially; however, the frequency of breeding has decreased in both regions, except near Barrow. Causes of this reduction in breeding frequency of Steller's Eiders in Alaska are unknown, but changes in predator populations, lead poisoning, and interspecific nesting associations with Snowy Owls (Nyctea scandiaca) and Pomarine Jaegers (Stercorarius pomarinus) may be contributing factors.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Polysticta stelleri; Steller's eider

Year-round movements of Long-tailed Ducks Clangula hyemalis from Kolguev Island, Barents Sea - Quillfeldt, P.; Morkunas, J.; Kruckenberg, H.; Kondratyev, A.; Loshchagina, J.; Aarvak, T.; Oien, I. J.; Bellebaum, J.; Glazov, P. (POLAR BIOLOGY, 2022)
Arctic birds migrating southwards face a multitude of challenges such as habitat loss, pollution, overexploitation of food resources and climate change impacts. Long-tailed Duck winter populations in the Baltic Sea have declined in recent decades. However, precise spatial data are lacking, especially from males. Thus, we aimed to identify the wintering grounds, timing of migration and stopover sites of males and females. We studied spatiotemporal distribution patterns of eight male and five female Long-tailed Ducks using implanted ARGOS satellite transmitters. Birds were tagged in the breeding season on Kolguev Island, Russia. After the breeding period, Long-tailed Ducks from Kolguev used three main post-breeding areas: most males undertook long distance eastward post-breeding migration to areas around the Yamal and Gydan peninsulas, while one male and four females moved short to the southeast coast of Kolguev, and one female moved to Mezhdusharsky Island in the Novaya Zemlya Archipelago. Autumn migration included stopover sites in the White Sea, Lake Ladoga, the Gulf of Finland and the Gulf of Riga, and all birds except one spent the winter in the southern part of the Baltic Sea, from the Pomeranian coast and Hoburgs bank to the Gulf of Finland. Only one female stayed in the White Sea for the winter. All but one bird used the White Sea as a stopover site in May, suggesting that this area is of special importance.
Times Cited in Web of Science Core Collection: 2 Total Times Cited: 3 Cited Reference Count: 57
Keywords: COMMUNITIES; Migration; CLIMATE-CHANGE; SEABIRDS; GILLNET FISHERIES; POPULATIONS; CLUPEA-HARENGUS L.; Home range analysis; Implant effects; Long-tailed ducks; Post-surgery survival; Satellite transmitters; Temporal patterns

Arctic Fox Alopex-Lagopus Predation on Nesting Common Eiders Somateria-Mollissima at Icy Cape Alaska USA - Quinlan, S. E.; Lehnhausen, W. A. (Canadian Field-Naturalist, 1982)
Arctic foxes, Alopex lagopus, preyed on common eiders, Somateria mollissima, nesting on a barrier island at Icy Cape, Alaska. Small clutches and late nesting in the common eiders possibly resulted from predation early in the season. Foxes had access to 1 barrier island via an estuarine mudflat and presumably swam to reach the adjacent island containing an eider colony. A single fox destroyed the colony, cached an estimated 500 eggs, and killed at least 1 female eider. Glaucous gull, (Larus hyperboreus) nests were also destroyed by foxes, but arctic tern (Sterna paradisaea) nests survived. Man-made causeways connecting the mainland to a barrier island could provide easier summer access to barrier island systems for foxes and thus pose a threat to common eider nesting colonies along the Chukchi and Beaufort Sea coasts.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Trophic Interactions

Impact of the construction of the hydroelectric power plant Freudenau (Vienna) on the wintering stocks of waterbirds on the Danube in Vienna - Raab, Rainer (Denisia, 2003)
From winter 1997/98 to winter 2000/01 the number of waterbirds on the Danube in Vienna as well as on the New Danube and on the Old Danube was counted in the course of 16 field trips per year. 44 species of waterbirds, six gulls and eight hybrid species and 391313 individuals respectively were observed. Most frequent was the Black-headed Gull with a maximum of 15579 individuals a day, Malard and Coot dominate among the waterbirds (without gulls). From 1994/95 to 2000/01, Danube area at Vienna was of national importance for seven waterbird species. The Danube met the criterion for five species, the Old Danube for two and the New Danube for all seven species. So far, the New Danube is the first and only waterbody with national importance for the Smew. Compared to the conditions before, neighter significant increase of the Tufted Duck, the Pochard and the Coot nor a decrease of the Goosander could be found during the first four years after the completion of the hydroelectric power plant Freudenau (Vienna). High numbers of waterbirds on the Danube at Vienna were observed only when the New Danube was largely frozen. In this case, some of the waterbirds on the New Danube moved to the Danube at Vienna. After the full damming up, waterbirds were nearly four times as abundant in stretches rich in structure (side channels and coves) as in poorly structured stretches. Coot, Mute Swan and Tufted Duck showed an even stronger preference for structures. The for ecological reasons great effort of creating a structured shoreline with coves and side channels was worth it for the waterbirds. In spite of the construction of the retainment area, no significant increase of midwinter waterbird numbers has been observed on the Danube at Vienna from 1964/65 (beginning of the waterbird census) to 2000/01.
Keywords: Conservation; Sea Ducks - General; Nonbreeding Seasons; Common merganser

Breeding Distribution and Habitat Selection of Red-Breasted Mergansers Mergus-Serrator in Fresh Water in Western Norway - Rad, O. (Wildfowl, 1980)
The breeding distribution and habitat selection of the red-breasted merganser, M. serrator, was investigated in west Norwegian freshwaters. The distribution is closely related to the distribution of the 3-spined stickleback, Gasterosteus aculeatus. The ducklings require small fishes, easily accessible in shallow waters. Stickleback is the only fish species in western Norway which fulfills these requirements. A female merganser selects her breeding habitat from the structural characteristics of lakes and from quality and quantity of the food present for the young.
Keywords: Breeding Season; Habitat; Mergus serrator; Red-breasted merganser

Fifteenth census of seabird populations in the sanctuaries of the North Shore of the Gulf of St. Lawrence, 1998-1999 - Rail, Jean-Fran; Chapdelaine, Gilles (Canadian Field-Naturalist, 2004)
For the first time since the tradition began in 1925, the quinquennial census of seabirds in the Migratory Bird Sanctuaries of the North Shore of the Gulf of St. Lawrence was divided between two years in 1998-1999. Trends between 1993 and 1998-1999 were variable across species and sanctuaries. In particular, following the large decreases in both species noted in 1993, the 1998-1999 survey showed that Black-legged Kittiwakes had declined further, while the number of Herring Gulls had stabilized. Alcids were all doing well except for the Atlantic Puffin which showed severe yet unexplained drops at all major colonies. Law enforcement efforts appear reflected in seabird population trends, as well-patrolled sanctuaries such as St. Mary's Islands seem to do well, whereas many species at the Baie des Loups and (I) over cap le a la Brume sanctuaries are far from their historical levels. In addition to a better law enforcement program, research is needed in order to identify other conservation problems that some species may be facing. .
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General

Sixteenth Census of Seabird Populations in the Sanctuaries of the North Shore of the Gulf of St. Lawrence, 2005 - Rail, Jean-Francois; Cotter, Richard (Canadian Field-Naturalist, 2007)
The Migratory Bird Sanctuaries of the North Shore of the Gulf of St. Lawrence are important breeding grounds for many seabird species. The quinquennial censuses of seabirds in these sanctuaries have been carried Out for 80 years (since 1925). in order to detect changes in the distribution and population levels of seabirds breeding on the North Shore. Between 1998-1999 and 2005, the most striking trends observed were the near doubling in numbers of Common Eiders in most sanctuaries, and the strong population growth rate of Razorbill. Unexplainable declines of Common Murre and Atlantic Puffin were observed at some of the larger colonies of these species. The last active colonies of Leach's Storm-Petrel (Corossol Island) and Caspian Tern (Ile a la Brume) on the North Shore seem on the verge of disappearing, with zero and three birds observed in 2005, respectively. Seabird populations in the larger, more accessible and disturbed sanctuaries are still markedly smaller than in historical times.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Common Eider; Somateria mollissima

Transmission and reassortment of avian influenza viruses at the Asian-North American interface - Ramey, Andrew M.; Pearce, John M.; Ely, Craig R.; Guy, Lisa M. Sheffield; Irons, David B.; Derksen, Dirk V.; Ip, Hon S. (Virology, 2010)
Twenty avian influenza viruses were isolated from seven wild migratory bird species sampled at St. Lawrence Island, Alaska. We tested predictions based on previous phylogenetic analyses of avian influenza viruses that support spatially dependent trans-hemispheric gene flow and frequent interspecies transmission at a location situated at the Asian-North American interface. Through the application of phylogenetic and genotypic approaches, our data support functional dilution by distance of trans-hemispheric reassortants and interspecific virus transmission. Our study confirms infection of divergent avian taxa with nearly identical avian influenza strains in the wild. Findings also suggest that H16N3 viruses may contain gene segments with unique phylogenetic positions and that further investigation of how host specificity may impact transmission of H13 and H16 viruses is warranted. Published by Elsevier Inc.
Keywords: Sea Ducks - General; Disease

Evidence for limited exchange of avian influenza viruses between seaducks and dabbling ducks at Alaska Peninsula coastal lagoons - Ramey, A. M.; Pearce, J. M.; Reeves, A. B.; Franson, J. C.; Petersen, M. R.; Ip, H. S. (Archives of Virology, 2011)
Times Cited: 3 Ramey, Andrew M. Pearce, John M. Reeves, Andrew B. Franson, J. Christian Petersen, Margaret R. Ip, Hon S. 3
Keywords: Nonbreeding Seasons; Disease; Sea Ducks

Sampling of Sea Ducks for Influenza A Viruses in Alaska during Winter Provides Lack of Evidence for Epidemiologic Peak of Infection - Ramey, A. M.; Reeves, A. B.; Poulson, R. L.; Wasley, J.; Esler, D.; Stallknecht, D. E. (Journal of Wildlife Diseases, 2015)
Sampling of sea ducks for influenza A viruses in Alaska during winter provided no evidence for an epidemiologic peak of infection. Isolates were recovered, however, that provide information on viral diversity and dispersal that may not be realized through sampling efforts focused on other avian taxa.
Ramey, Andrew M. Reeves, Andrew B. Poulson, Rebecca L. Wasley, Jeff Esler, Daniel Stallknecht, David E.
Keywords: Melanitta fusca; White-winged Scoter; Melanitta perspicillata; Surf Scoter; Histrionicus histrionicus; Clangula hyemalis; Long-tailed Duck; King Eider; Somateria spectabilis; Disease; Black Scoter; Bucephala islandica; Nonbreeding season; Barrow’s Goldeneye; Melanitta americana; Harlequin Duck

OCCURRENCE AND IMPLICATIONS OF STAGING BLACK SCOTERS MELANITTA AMERICANA IN A HEAVILY TRAFFICKED URBAN ESTUARY - Ramirez-Garofalo, J. R. (MARINE ORNITHOLOGY, 2020)
During a land-based survey of wintering seaducks, I detected approximately 50 000 Black Scoters Melanitta americana on the Lower New York Bay. which borders both New York and New Jersey. During their 14-day stay, the scoters were regularly disturbed by large container vessels and smaller watercraft, but consistent numbers remained throughout the survey. Based on recent population estimates, this congregation of Black Scoters represents 16.6% to 25% of the eastern North American population. Using data from the National Audubon Society Christmas Bird Count, I found that Black Scoters have dramatically increased in abundance during the winter on count circles at sites around the bay; however those increases were not correlated with North Atlantic Oscillation indices averaged over October-December each year from 1990 to 2017. Bivalve mollusks, a major food source for Black Scoters, are abundant throughout the bay. and they have likely played a role in the increased use of the bay by this species. Local efforts to restore Eastern Oyster Crassostrea virginica populations to the bay may promote increased use by Black Scoters and other seaducks, providing an opportunity for targeted conservation efforts. Current plans to build a surge gate at the mouth of the bay as a storm-risk mitigation measure may result in the Lower Bay being avoided by Black Scoters and other seaducks. which in turn may have negative population-level effects for these seaduck species.
Times Cited in Web of Science Core Collection: 1 Total Times Cited: 1 Cited Reference Count: 64
Keywords: conservation; ABUNDANCE; SELECTION; MOVEMENTS; Melanitta americana; SEA DUCKS; HABITAT USE; DISTRIBUTIONS; WINTER; WATERFOWL; Black Scoters; New York City; northwestern Atlantic; seaduck; SOUTHERN NEW-ENGLAND; urban estuary

Increased male bias in eider ducks can be explained by sex-specific survival of prime-age breeders - Ramula, S.; Ost, M.; Linden, A.; Karell, P.; Kilpi, M. (PLOS ONE, 2018)
In contrast to theoretical predictions of even adult sex ratios, males are dominating in many bird populations. Such bias among adults may be critical to population growth and viability. Nevertheless, demographic mechanisms for biased adult sex ratios are still poorly understood. Here, we examined potential demographic mechanisms for the recent dramatic shift from a slight female bias among adult eider ducks (Somateria mollissima) to a male bias (about 65% males) in the Baltic Sea, where the species is currently declining. We analysed a nine-year dataset on offspring sex ratio at hatching based on molecularly sexed ducklings of individually known mothers. Moreover, using demographic data from long-term individual-based capture-recapture records, we investigated how sex-specific survival at different ages after fledgling can modify the adult sex ratio. More specifically, we constructed a stochastic two-sex matrix population model and simulated scenarios of different survival probabilities for males and females. We found that sex ratio at hatching was slightly female-biased (52.8%) and therefore unlikely to explain the observed male bias among adult birds. Our stochastic simulations with higher survival for males than for females revealed that despite a slight female bias at hatching, study populations shifted to a male-biased adult sex ratio (> 60% males) in a few decades. This shift was driven by prime reproductive-age individuals(>5-year-old), with sex-specific survival of younger age classes playing a minor role. Hence, different age classes contributed disproportion ally to population dynamics. We argue that an alternative explanation for the observed male dominance among adults sex-biased dispersal can be considered redundant and is unlikely, given the ecology of the species. The present study highlights the importance of considering population structure and age-specific vital rates when assessing population dynamics and management targets.
Times Cited in Web of Science Core Collection: 17 Total Times Cited: 19 Cited Reference Count: 49
Keywords: CONSEQUENCES; COMMON EIDERS; SOMATERIA-MOLLISSIMA; MOVEMENTS; POPULATION; DYNAMICS; SYSTEM; DISPERSAL; COST; RATIO

Timing of nesting of upland-nesting ducks in the Canadian prairies and its relation to spring wetland conditions - Raquel, A. J.; Devries, J. H.; Howerter, D. W.; Alisauskas, R. T.; Leach, S. W.; Clark, R. G. (CANADIAN JOURNAL OF ZOOLOGY, 2016)
Timing of breeding varies among waterfowl species and individuals, with strong effects on reproductive success, and may be related to habitat quality. Here, we analyse the start, span, and end of the nesting season for nine upland-nesting duck species at 166 Canadian Prairie-Parkland sites over 34 years to better characterize nesting patterns and test whether and how species respond to May pond abundances. Nesting metrics were compared between single-site versus multiple-site studies over 7 years to evaluate the effects of spatial scale and methodology. Strong, consistent differences in start of nesting were found among duck species, being earliest for Northern Pintail (Anas acuta L., 1758) and Mallard (Anas platyrhynchos L., 1758), followed by Northern Shoveler (Anas clypeata L., 1758), American Green-winged Teal (Anas crecca carolinensis Gmelin, 1789 = Anas carolinensis Gmelin, 1789), Blue-winged Teal (Anas discors L., 1766), American Wigeon (Anas americana Gmelin, 1789), Gadwall (Anas strepera L., 1758), and lastly by Lesser Scaup (Aythya affinis (Eyton, 1838)) and White-winged Scoter (Melanitta fusca deglandi (Bonaparte, 1850)). Span and end of nesting were related to May pond abundances, but the strength of these relationships varied among species, presumably reflecting the flexible (re-)nesting potential of individuals of some species in response to wetland-habitat quality.
Times Cited in Web of Science Core Collection: 8 Total Times Cited: 8 Cited Reference Count: 48
Keywords: waterfowl; SIZE; ECOLOGY; AYTHYA-AFFINIS; LESSER SCAUP; SUCCESS; DUCKLINGS; MELANITTA-FUSCA-DEGLANDI; Anas spp.; Aythya affinis; HATCH DATE; initiation date; life-history variation; MALLARD BROOD SURVIVAL; Melanitta fusca deglandi; nesting chronology; pond abundance; Prairie Pothole Region; SEASONAL-VARIATION

Trends in Eggshell Thickness and Mercury in Common Goldeneye and Hooded Merganser Eggs - Rave, D. P.; Zicus, M. C.; Fieberg, J. R.; Savoy, L.; Regan, K. (Wildlife Society Bulletin, 2014)
Environmental contaminants such as dichloro diphenyl trichloroethane (DDT), polychlorinated biphenyls (PCBs), and mercury are associated with physiological problems in wildlife. DDT and PCBs were banned in North America in the 1970s, but these contaminants sometimes persist in the environment and can cause reproductive problems, including eggshell thinning. In contrast, mercury deposition from anthropogenic sources is a continuing if not growing concern globally. We measured thickness of common goldeneye (Bucephala clangula) and hooded merganser (Lophodytes cucullatus) eggshells collected in 2003-2004 in Minnesota, USA, to compare with measurements taken prior to (approx. 1900) and after (1981) widespread DDT use. We also compared egg-mercury concentration (ppm) in goldeneye and merganser eggs collected in 2003-2004 with a 1981 collection. Mean eggshell thickness was 0.401 mm (SE = 0.003) and 0.606 mm (SE = 0.008) for goldeneyes and mergansers, respectively. This was 9.0% (goldeneyes) and 6.0% (mergansers) greater than in 1981. Mean thickness of goldeneye eggshells remained 7.8% less than the mean prior to widespread DDT use; whereas, merganser eggshell thickness was statistically similar to pre-DDT thickness. Mean Ratcliffe's index, a measure of eggshell quality, also increased for goldeneyes (2.52, SE = 0.021) and mergansers (3.78, SE = 0.042) since 1981. Goldeneye values were statistically similar to, while merganser values remained 5.6% less than, pre-DDT values. Geometric mean concentrations of mercury (wet wt) have declined since 1981 in merganser eggs (0.33 ppm, SE = 0.024), and were statistically unchanged in goldeneye eggs (0.13 ppm, SE = 0.011). Continued monitoring of wildlife populations for contaminants is important because wildlife may serve as an indicator of overall ecosystem health. (C) 2013 The Wildlife Society.
Rave, David P. Zicus, Michael C. Fieberg, John R. Savoy, Lucas Regan, Kevin
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Contaminants; Hooded Merganser; Lophodytes cucullatus

Changes in Distribution and Abundance of Birds on Western Victoria Island from 1992-1994 to 2004-2005 - Raven, G.H.; Dickson, D.L. (Technical Report Series, 2006)
Annual waterfowl breeding population surveys do not adequately cover breeding grounds for many species nesting in the Canadian arctic. Baseline surveys were conducted on western Victoria Island 1992-1994. In 2004 and 2005 we resurveyed western Victoria Island to obtain current population estimates and determine trends for bird species since the 1992-1994 surveys. We calculated visibility correction factors (VCF) for the three main species encountered during the 2004-2005 surveys using a double-count method. The VCF for King Eiders (Somateria spectabilis) was 1.435, for Canada Geese (Branta hutchinsii) was 1.617, and for Long-tailed Duck (Clangula hyemalis) was 1.833. The mean breeding population estimate for King Eiders on western Victoria Island in 2004-2005 was 33 199, which is 54% below the mean estimate from the 1992-1994 surveys. Proportional population decreases occurred throughout western Victoria Island for King Eiders except on Diamond Jenness Peninsula where estimates decreased by 92%. Long-tailed Duck densities remained low throughout western Victoria Island and population estimates were slightly below those from the 1992-1994 surveys. The mean breeding population estimate for Canada Geese on western Victoria Island was 80 092; an increase of 18% over the 1992-1994 mean estimate. Mean estimates for Canada Geese on Prince Albert Peninsula increased by 244% between the two survey periods indicating the breeding range is expanding northward. White-fronted Geese (Anser albifrons) were common in the southwest but rare on northwestern Victoria Island, and showed no change in number between survey periods. Lesser Snow Geese (Chen caerulescens caerulescens) numbers more than doubled on southwestern Victoria Island between the two survey periods. Most observations were small flocks of non-breeders. Black Brant (Branta bernicla nigricans) were very rare on western Victoria Island and numbers have continued to decrease since the surveys were last completed. Estimates of Tundra Swans (Cygnus columbianus) were low in 2004 but rebounded in 2005. A late spring occurred on western Victoria Island in 2004 and likely affected estimates. More typical spring conditions were observed in 2005. Highest densities on Tundra Swans occurred in the Kagloryuak River valley and southwestern Victoria Island. Few swans were seen north of Prince Albert Sound. Sandhill Crane (Grus canadensis) observations on northwestern Victoria Island were low in 2004 but similar to swans they rebounded in 2005 to numbers more representative of the earlier surveys. Three species of loons (Gavia spp.) were observed on western Victoria Island: Yellowbilled Loons (G. adamsii), Red-throated Loons (G. stellata), and Pacific Loons (G. pacifica). Loons were distributed throughout western Victoria Island. Population indices for northwestern Victoria Island were lower than those observed in the previous surveys but numbers were stable in southwestern Victoria Island. Three species of jaegers (Stercorarisu spp.) were observed on western Victoria Island: Pomarine Jaegers (S. pomarinus), Parasitic Jaegers (S. parasiticus), and Long-tailed Jaegers (S. longicaudus). Jaeger numbers decreased since the 1992-1994 surveys, although a rebound occurred in 2005, largely due to an increasing number of Pomarine and Long-tailed Jaegers. The population rebound of Pomarine and Long-tailed Jaegers occurred in conjunction with a rebound in Snowy Owl (Bubo scandiacus) numbers, another predator of lemmings. Other raptors observed on western Victoria Island were Rough-legged Hawks (Buteo lagopus), Peregrine Falcons (Falco peregrinus), and Short-eared Owls (Asio flammeus). Glaucous Gulls (Larus hyperboreus) were widespread throughout western Victoria Island with a distribution similar to that observed during the 1992-1994 surveys. Although numbers were low in 2004 compared to the earlier surveys, they appeared to recover in 2005.
Keywords: Common Eider; Clangula hyemalis; Long-tailed Duck; Somateria mollissima; Breeding season; King Eider; Somateria spectabilis; Abundance, Distribution, & Trends

Surveys of Pacific Common Eiders (Somateria mollissima v-nigra) in the Bathurst Inlet area of Nunavut, 2006-2008. - Raven, G.H.; Dickson, D.L. (Technical Report Series, 2009)
There is currently no regular breeding population survey to monitor Pacific Common Eider (Somateria mollissima v nigra) population trends in Canada. Concern for this subspecies of eider arose when migration counts showed a decline of more than 50% in the Canadian breeding population between 1976 and 1996. A survey of much of their breeding range in the central arctic in 1995 indicated that about 25% of the Canadian breeding population occurs within the Bathurst Inlet area of Nunavut. Given the relatively high density of eiders, isolation from the rest of the breeding range and logistical feasibility, we selected the Bathurst Inlet area to establish a baseline for monitoring the Canadian breeding population of Pacific Common Eider. Accordingly, we conducted three years of surveys from 2006-2008 using a technique similar to that used in 1995. We surveyed for eiders during the early stages of nest initiation each year between 24 June and 2 July. Near complete survey coverage was attained in 1995, 2007 and 2008, while in 2006 only about a third of the study area was surveyed. Numbers of Pacific Common Eiders observed in 2007 were 4233 males and 4048 females. Results were similar but slightly higher in 2008 with 4916 males and 4578 females observed. These numbers are well below totals observed for the same areas in 1995 when 8950 males and 7809 females were observed. These data indicate a 43.3 - 50.6% decline in number of eiders in the Bathurst Inlet area since 1995. Detection surveys using a double-counting technique were conducted in each of the three recent years of the survey. In 2006 limited effort was put forth for detection surveys due to limitations with aircraft time and weather. Detection surveys that year were done in areas with low eider densities resulting in a small sample size and a visibility correction factor (VCF) of 2.04. In 2007 and 2008 detection surveys were conducted in areas with higher eider densities, which better reflected the overall eider count, and resulted in a VCF of 1.19 and 1.12 respectively. Combining the 3 years of detection surveys yielded a VCF value of 1.18. Based on this pilot study, we conclude that an effective and efficient breeding population survey for Pacific Common Eiders can be completed in the Bathurst Inlet area in 3 to 4 days when timed accordingly and conditions are favourable. Given the recent continental decline of Pacific Common Eiders and the increased resource development in arctic regions including the Beaufort Sea and Bathurst Inlet area, we recommend this survey in the Bathurst Inlet area become an on-going operational survey. An annual survey would be ideal, but at the very least the survey should be conducted for 3 years every 10 years. Consideration should be given to expanding the survey to include the nearby offshore islands in northern Queen Maud Gulf.
Keywords: Common Eider; Somateria mollissima; Breeding season; SDJV funded; Abundance, Distribution, & Trends

Diel activity patterns of lake chubs and other fishes in a temperate stream - Reebs, S. G.; Boudreau, L.; Hardie, P.; Cunjak, R. A. (Canadian Journal of Zoology, 1995)
Baited and unbaited minnow traps were set in Catamaran Brook and the Little Southwest Miramichi River, New Brunswick, and checked every 4 h to determine the diel activity pattern of four species of stream-dwelling fish (threespine stickleback (Gasterosteus aculeatus), juvenile white sucker (Catostomus commersoni), blacknose dace (Rhinichthys atratulus), and lake chub (Couesius plumbeus)). Secondary goals were to determine whether the presence of bait inside minnow traps affected the diel patterns of captures and to compare patterns of lake chub captures in minnow traps with movement through a nearby fish-counting fence. All fish except lake chubs were diurnal, although strict diurnality was less obvious when bait was present in the traps. Lake chubs, which are normally diurnal in the laboratory, were captured mostly near dawn or dusk in unbaited traps, throughout the day in baited traps, and mostly at night at the fish-counting fence. We infer that chubs are active mostly at dawn or dusk, except (i) when strong food cues are present, in which case their activity may extend into the day, and (ii) during the spawning migration, when they move mostly at night. Relative inactivity by chubs during the day may be caused by the presence of piscivorous birds such as kingfishers and common mergansers, whose hunting efficiency may be higher under brighter light.
Keywords: Trophic Interactions; Common merganser; Mergus merganser

Canadian Wildlife Service Report Series No. 47. Eider Ducks in Canada - Reed, A. (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)
This volume consists of 18 papers written by various authors. The book is divided into 6 parts: distribution and abundance, races of common eiders, distribution in winter, ecology, use by people, and conclusions. Twelve of the papers are written in English and five are in French. Both French and English versions of the final paper are provided. Each paper has an abstract in French and English and eleven of the papers have an additional abstract in Inuktitut. Three appendices and a list of other publications in the Report Series are also included.
Keywords: Breeding Season; Common Eider; Nonbreeding Seasons; Somateria mollissima

Eiderdown Harvesting and Other Uses of Common Eiders in Spring and Summer - Reed, A. (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: Conservation; Breeding Season; Common Eider; Somateria mollissima

Surf scoter, Melanitta perspicillata, nesting in Southern Quebec - Reed, Austin; Aubry, Yves; Reed, Eric (Canadian Field-Naturalist, 1994)
In late May, 1993, a Surf Scoter, Melanitta perspicillata, nest was found at 664 ha Malbaie Lake in the Laurentide Wildlife Reserve 95 km NNE of Quebec City. During subsequent brood surveys of the lake several broods were present and a peak count of 139 ducklings was obtained. This is the only published record of a nest in Quebec since 1833; the density of breeding pairs in the lake was high relative to other areas, and the lake is well south of the previously described range. The high elevation of Malbaie Lake (820 m) creates ecological conditions similar to those found in the typical high boreal-subarctic range of the species.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Melanitta perspicillata; Surf Scoter

Distribution and Abundance of Waterfowl Wintering in Southern Quebec - Reed, A.; Bourget, A. (Canadian Field-Naturalist, 1977)
In Jan. and Feb. of 1974, 1975 and 1976, surveys of wintering waterfowl were conducted through most open-water areas of S Quebec [Canada]. These surveys indicated the presence of at least 171,000 ducks, mostly diving and sea ducks in the estuary and Gulf of St. Lawrence. Inland freshwater areas, mainly in the Montreal region, supported many common goldeneye (Bucephala clangula), common merganser (Mergus merganser) and black duck (Anas rubripes). The most abundant ducks on the estuarine portion were oldsquaw (Clangula hyemalis), common and Barrow's (Bucephala islandica) goldeneyes and black duck. In the gulf, common eider (Somateria mollissima), oldsquaw, common and Barrow's goldeneyes were abundant. The area of the estuary and gulf is of international importance as a sea- and dividing-duck wintering ground. Further study and close surveillance are required owing to the birds' apparently great vulnerability to oil pollution and habitat change in a very rigorous climate.
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons

Colonial Nesting Water Birds in the St-Lawrence River - Reed, A.; Chapdelaine, G. (Ibis, 1978)
Keywords: Breeding Season; Common Eider; Somateria mollissima

Epidemics involving the common eider (Somateria mollissima) at He Blanche, Quebec - Reed, Austin; Cousineau, J. Guy (Natur Can, 1967)
During the period 1963-66, two important outbreaks of epidemics amongst nesting common eiders (Somateria mollissima) have been observed,one in 1964 and the other in 1966. Both epidemics occurred on one of the several nesting islands under observation in the St. Lawrence Estuary. An estimated 1000 adult female eiders succumbed to the disease in 1964 and 700 in 1966. Total population for this island was about 4000 nesting females in each year. Post mortem and bacteriological investigations revealed Pasteurella multocida, the agent of fowl cholera, as the cause of death, None of the other bird species sharing this island, including the herring gull (Larus argentatus) and the double-crested cormorant (Phalacrocorax auritus) suffered mortality and bacteriological examinations of several specimens were negative for fowl cholera. The source of the infection remains unknown but the intensity of the epidemics is attributed partially to high nesting densities and humid conditions in and around the nests. Further study is proposed to clarify certain aspects of these outbreaks. || ABSTRACT AUTHORS: Author
Keywords: Breeding Season; Common Eider; Somateria mollissima; Survival; Disease

Races of the Common Eider Wintering in the Gulf of St. Lawrence Canada - Reed, A.; Dupuis, P.; Bourget, A.; Mendall, H. L. (Reed, A. (Ed.). Canadian Wildlife Service Report Series, No. 47. Eider Ducks in Canada. V+177p. Canadian Wildlife Service: Ste-Foy, Quebec, Canada. Illus. Maps. Paper, 1987)
Keywords: Common Eider; Nonbreeding Seasons; Somateria mollissima; Population Delineation

Populations of the Common Eider in the Eastern North America Their Size and Status - Reed, A.; Erskine, A. J. (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

Movements and foraging effort of Steller's Eiders and Harlequin Ducks wintering near Dutch Harbor, Alaska - Reed, John A.; Flint, Paul L. (Journal of Field Ornithology, 2007)
We studied the movements and foraging effort of radio-marked Steller's Eiders (Polysticta stelleri) and Harlequin Ducks (Histrionicus histrionicus) to evaluate habitat quality in an area impacted by industrial activity near Dutch Harbor, Alaska. Foraging effort was relatively low, with Steller's Eiders foraging only 2.7 +/- 0.6 (SE) hours per day and Harlequin Ducks 4.1 +/- 0.5 hours per day. Low-foraging effort during periods of high-energetic demand generally suggests high food availability, and high food availability frequently corresponds with reductions in home range size. However, the winter ranges of Harlequin Ducks did not appear to be smaller than usual, with the mean range size in our study (5.5 +/- 1.1 km(2)) similar to that reported by previous investigators. The mean size of the winter ranges of Steller's Eiders was similar (5.1 +/- 1.3 km(2)), but no comparable estimates are available. Eutrophication of the waters near Dutch Harbor caused by seafood processing and municipal sewage effluent may have increased populations of the invertebrate prey of these sea ducks and contributed to their low-foraging effort. The threat of predation by Bald Eagles (Haliaeetus leucocephalus) that winter near Dutch Harbor may cause Steller's Eiders and Harlequin Ducks to move further offshore when not foraging, contributing to an increase in range sizes. Thus, the movement patterns and foraging behavior of these ducks likely represent a balance between the cost and benefits of wintering in a human-influenced environment.
Keywords: Behavior; Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Dispersal; Polysticta stelleri; Steller's eider

Depredation of Common Eider, Somateria mollissima, Nests on a Central Beaufort Sea Barrier Island: A Case Where No One Wins - Reed, John A.; Lacroix, Deborah L.; Flint, Paul L. (Canadian Field-Naturalist, 2007)
Along the central Beaufort Sea. Pacific Common Eiders (Somateria mollissima v-nigra) nest on unvegetated, barrier islands: often near nesting Glaucous Gulls (Larus hyperboreus). Nest-site choice likely reflects a strategy of predator avoidance: nesting on islands to avoid mammalian predators and near territorial gulls to avoid other avian predators. We observed a nesting colony of Common Eiders from first nest initiation through nesting termination on Egg Island near Prudhoe Bay, Alaska (2002 - 2003). Resident gulls depreciated many eider nests, mostly during initiation. All nests failed when an Arctic Fox (Alopex lagopus) visited the island and flushed hens from their nests, exposing the eggs to depredation by the fox and gulls (resident and non-resident). Common Eiders actively defended nests from gulls, but not from foxes. Likely all three species (i.e.. eiders, gulls. and foxes) ultimately achieved negligible benefit from their nest-site selection or predatory activity: (a) island nesting provided no safety from mammalian predators for ciders or gulls. (b) for Common Eiders, nesting near gulls increased egg loss, (c) for Glaucous Gulls, nesting near colonial ciders may have reduced nest success by attracting the fox, and (d) for Arctic Foxes, the depredation was of questionable value, as most eggs were cached and probably not recoverable (due to damage from fall storms). Thus, the predator-prey interactions we observed appear to be a case where little or no fitness advantage was realized by any of the species involved.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Productivity; Trophic Interactions

Evidence for Haemosporidian Parasite Infections in Spectacled Eiders (Somateria fischeri) Sampled in Alaska, USA during the Breeding Season - Reed, J. A.; Sexson, M. G.; Smith, M. M.; Schmutz, J. A.; Ramey, A. M. (JOURNAL OF WILDLIFE DISEASES, 2018)
We assessed hematozoa infection in Spectacled Eiders (Somateria fischeri) at two areas in Alaska, US. No Haemoproteus or Plasmodium species were detected. Leucocytozoon prevalence was 6.5% for adults across sites and 41.9% for juveniles sampled in the Arctic, providing evidence for local transmission. All Leucocytozoon haplotypes were previously detected in waterfowl.
Times Cited in Web of Science Core Collection: 4 Total Times Cited: 4 Cited Reference Count: 15
Keywords: BIRDS; PREVALENCE; BLOOD PARASITES; GENETIC DIVERSITY; HEMATOZOA; MALARIA; MOLECULAR-DETECTION

Survival and movement of postfledging juvenile harlequin ducks - Regehr, Heidi M. (Wilson Bulletin, 2003)
Age specific survival and movement are important components of demography and population structure, and quantification of these rates is useful for management and conservation. However, information on the postfledging ecology of waterfowl species frequently is unavailable to managers. I studied postfledging survival and movements of juvenile Harlequin Ducks (Histrionicus histrionicus) in the Strait of Georgia, British Columbia, using radio marking and capture-mark-recapture analysis of banded birds captured at coastal wintering areas. Survival of juvenile females was high, providing evidence that female winter survival may be similar among age groups. Radio-marked juvenile males were more likely to die than juvenile females, and juvenile males had lowest local survival rates of all sex-age classes. Proportions of banded juveniles found at their capture location during their second winter did not differ significantly between males and females, suggesting equal dispersal rates, and at least 25% (n = 9) of radio-marked females moved >30 km from their capture location. These results were unexpected, based on previous evidence for female philopatry and theories of male-biased dispersal in waterfowl, and suggest that males and females both likely contribute to gene flow and demographic connection among populations.
Keywords: Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Dispersal; Survival; Population Delineation

Movement Rates and Distances of Wintering Harlequin Ducks: Implications for Population Structure - Regehr, Heidi M. (Waterbirds, 2011)
Population structure of Harlequin Ducks (Histrionic-us histrionicus) wintering in the Strait of Georgia, British Columbia, was evaluated by generating age, sex, paired status and distance-specific movement rates with multi-stratum mark-recapture analyses, and age and sex-specific movement distances through surveys of marked individuals. Annual movement distances and rates did not differ by sex, but only 2-4% of adults (third year and after-third year) compared to 7-11% of subadults (hatch year and second year) moved among locations per year and distance moved decreased with age. Adults were highly site faithful regardless of sex and paired status. The stepping stone gene flow model estimated the among population component of genetic variance (F-ST) at 0.005, suggesting that winter movement by subadults was sufficient to explain results of previous genetic analyses that detected no fine scale genetic structuring. Seasonal movement rates indicated that at least 95% of individuals molt and winter in the same location, and that annual aggregation at Pacific Herring (Clupea pallasi) spawning sites facilitates demographic mixing and gene flow. Low annual movement rates (0.001) between the northern and southern Strait of Georgia and dispersal by both sexes suggest that a metapopulation distribution may function within the Pacific Coast range, which is relevant to the geographic scale of management. Movement rates and distances suggest that subadult survival rates are particularly vulnerable to underestimation. Received 28 February 2010, accepted 3 June 2010.
Keywords: Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Dispersal; Population Dynamics; Population Delineation

Evaluation of nasal discs and colored leg bands as markers for Harlequin Ducks - Regehr, Heidi M.; Rodway, Michael S. (Journal of Field Ornithology, 2003)
We evaluated nasal discs and colored leg bands for Harlequin Ducks (Histrionicus histrionicus) wintering in the Strait of Georgia, British Columbia, by comparing marker visibility and life span, and determining effects of nasal discs on behavior and pairing. Proportions resighted and frequency of sightings were higher for individuals marked with nasal discs than for those marked only with leg bands. Nasal disc loss followed a logistic function that predicted 50% loss by 396 d. Due to wear of leg bands, number of sightings per individual decreased with leg band age following a cubic function. We detected no effects of nasal discs on time spent in various behaviors, timing of pairing, or female pairing success. However, males with nasal discs had lower pairing success, and females with nasal discs were less likely to reunite with previous mates. We speculate that the effect of nasal discs on male pairing success may be due to a male-biased sex ratio and sexual selection on male appearance. Leg band wear should be considered for demographic models because its effects can violate assumptions and bias sighting and survival estimates.
Keywords: Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Techniques

Post-fledging broods of migratory Harlequin Ducks accompany females to wintering areas - Regehr, Heidi M.; Smith, Cyndi M.; Arquilla, Brian; Cooke, Fred (Condor, 2001)
We describe evidence that Harlequin Duck (Histrionicus histrionicus) broods accompany their mothers from breeding streams to coastal molting or wintering areas. Observations indicated that all surviving female-offspring groups left breeding areas together. We later sighted some family members at the coast near each other, suggesting that they had arrived together, then separated. We observed family groups at wintering areas in August and September. Family groups tended to separate quickly, although some family members maintained contact for over five months. To our knowledge the evidence we provide is the first suggesting that female migratory ducks bring their offspring to wintering areas, a pattern similar to geese and swans. This may be facilitated by an unusual strategy of wing molt, in which Harlequin Ducks molt after migrating to wintering areas. Due to winter pairing and strong philopatry in Harlequin Ducks, migration of families may contribute to genetic differentiation among populations.
Keywords: Breeding Season; Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Dispersal; Population Delineation

Morphology and Life Cycle of Echinocotyle-Clanguli New-Species Cestoda Hymenolepididae - Regel, K. V. (Parazitologiya (St. Petersburg), 1987)
The morphology and life cycle of the cestode Echinocotyle clanguli sp. n. parasitic in long-tailed ducks in East Subarctic are described. The new species differs from the earlier described hymenolepidids of this genus in comparatively large size (the cestode lenght is 56 to 89 mm), length of the proboscis hooks (49 to 51 .mu.), peculiar armature of adhesive suckers (thin cuticular spines covering the whole surface of suckers) and structure of the copulatory organ. Copulating couples of cestodes are described. The data on the developmental periods of the new species in the definitive and intermediate hosts were obtained.
Keywords: Clangula hyemalis; Long-tailed Duck; Parasites

To the fauna of the cestode family Hymenolepididae from ducks of Chukotka : Microsomacanthus parasobolevi sp n. - A widely distributed parasite of eider ducks - Regel, K. V. (Parazitologiya (St. Petersburg), 2005)
A new species of the genus Microsomacanthus Lopez-Neyra, 1942 is described. The material was collected from eider ducks (Somateria mollissima, S. fischeri, and S. spectabilis) in the Chaunskaya lowland (North-Western Chukotka). Microsomacanthus parasobolevi sp. n. differs from the closest species of this genus (M. polystictae Regel, 1988, M. sobolevi Spassky et Jurpalova, 1964; M. strictophalius Tolkatchieva, 1966) by the structure and size of the copulatory organ. Wide distribution of the new species was detected based on the cestodes collections from eider ducks of the Eastern Chukotka, Lena River mouth (in the museum of the Institute of the Parasitology RAS) and Iceland (Karl Skirnisson's cestode collection of the common eider). Furthermore, this species was reported once of the common eider in Newfoundland and Labrador, but erroneously identified as Hymenglejns (Microsomacanthnis) formosoides Spasskaja et Spassky, 1961 by Bishop and Threlfall (1974).
Keywords: Common Eider; Somateria mollissima; Parasites

Spine Deficiency and Polymorphism in a Population of Gasterosteus-Aculeatus an Adaptation to Predators - Reimchen, T. E. (Canadian Journal of Zoology, 1980)
A population of G. aculeatus from a muskeg lake on the Queen Charlotte Islands shows a spine polymorphism, with 80% lacking the second dorsal spine and 68% lacking the pelvic spines. Females were more prevalent among phenotypes with greater spine number, and males were more common among those with fewer spines. Adult females and juveniles of both sexes with pelvic spines, were more frequent in the limnetic habitat; adult males and juveniles without pelvic spines were common in the littoral region. Species (5) of piscivorous birds, each in low numbers, foraged in the lake. Extensive predation in the limnetic region by Gavia immer and, secondarily, Podiceps spp. [P. grisegena and P. auritus], is implicated as a selective pressure favoring the greater spined phenotype. [Other bird species were Mergus Merganser, M. serrator, Lophodytes cucullatus and Megaceryle alcyon]. Odonate nymphs (Aeshna spp.) consumed juvenile fish in predation experiments and in the lake proper. Nymphs were common in the littoral zone, where submerged debris provided substrate for foraging. Spine loss in this population of G. aculeatus is an adaptation to the hunting technique of Aeshna; reduced external structures such as spines minimize frictional contact for a grappling predator. Experimental data and other gasterosteid populations are discussed with reference to these proposals.
Keywords: Trophic Interactions; Common merganser; Mergus merganser

Seasonal and Diurnal Abundance of Aquatic Birds on the Drizzle Lake Reserve Queen Charlotte Islands British-Columbia Canada - Reimchen, T. E.; Douglas, S. (Canadian Field-Naturalist, 1984)
A 112 ha lake on the Argonaut Plain, Queen Charlotte Islands, was surveyed for abundance and movement of birds at weekly intervals from 1978-1982. Thirty-six species used the lake; species numbers were highest in April and May and total bird-days highest in Oct. and Nov. The majority of individuals were non-breeding and used the lake for foraging or overnighting red-throated Loon, common Loon, Canada goose, mallard and common merganser, which moved between nearby marine water and the lake on a daily basis, accounted for the greatest number of yearly bird-days. Estimates of yearly prey consumption by piscivores at the lake range from 0.25-0.49 g m2.
Keywords: Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons; Common merganser

Size-dependent foraging behaviour and use of cover in juvenile coho salmon under predation risk - Reinhardt, Ulrich G.; Healey, Michael C. (Canadian Journal of Zoology, 1997)
Foraging and use of cover by juvenile coho salmon (Oncorhynchus kisutch) were affected by predation threat in both seminatural channels and laboratory streams. In the field, coho salmon preferred stream sections with brushy cover only when under threat from hunting common mergansers. The mergansers had their highest capture success in pools without cover. Predation threat also caused coho salmon to use cover more as foraging habitat and to aggregate more in favourable positions at the head of the pool. In the laboratory, under simulated predation threat, fish using a refuge were significantly larger than those in the risky habitat. This pattern persisted for 2 days after the predation threat was discontinued. The average growth of coho salmon under predation threat was depressed and the difference in growth between large and small individuals was less than in control groups. We argue that larger fish were more averse to predation risk than smaller fish and that the smaller fish took advantage of feeding opportunities indirectly provided as a result of the predation risk. We speculate that in natural environments, predation may depress growth rates because of risk-avoidance behaviour but may also serve to reduce growth-rate differences among size classes within a cohort.
Keywords: Trophic Interactions; Common merganser; Mergus merganser

An assessment of retaining dams in hydropower reservoirs for enhancing bird habitat - Reitan, Ole; Sandvik, Jostein (Regulated Rivers Research and Management, 1996)
The River Inna in the south Norwegian subalpine region was regulated in 1979-1982, creating a 6.7 km-2 reservoir with a 35 m range in water level. This reservoir inundated good habitat for wetland birds and, in general, provided poor habitat for birds. Along the main inflow river, but within the reservoir, a retaining dam was constructed after the breeding season in 1989 to create habitat for native ducks. The dam maintains a nearly constant water level about 1 m below the highest water level in the reservoir; this is especially important for ducks throughout the breeding season. The ducks showed an immediate response in the first season, increasing both in number of species and number of individuals of several species. To discern some factors responsible for attracting ducks to this pond, all ducks were censused at least 12 times each breeding season between 1990 and 1994. The numbers varied widely, both from one year to another and during each breeding season. Wigeon (Anas penelope) numbers after dam construction were highest early in the season. Tufted duck (Aythya fuligula) numbers mainly varied from one year to another, while long-tailed duck (Clangula hyemalis) numbers varied greatly through the season. In general, variations in water level had little effect on duck numbers. Four species established breeding populations in the pond. Such ponds may be valuable for establishing duck populations in many areas otherwise unsuitable for breeding water-birds. Appropriate management may also improve the chances of this being a rich habitat for several duck species in the future.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Clangula hyemalis; Long-tailed Duck; Habitat

Observations on the Time Budget and Diving Ecology of Long-Tailed Ducks in Eqalungmiut Nunaat West Greenland - Reynolds, P. (Wildfowl, 1987)
Keywords: Behavior; Clangula hyemalis; Long-tailed Duck

Drag-Based 'Hovering' in Ducks: The Hydrodynamics and Energetic Cost of Bottom Feeding - Ribak, Gal; Swallow, John G.; Jones, David R. (PLoS One, 2010)
Diving ducks use their webbed feet to provide the propulsive force that moves them underwater. To hold position near the bottom while feeding, ducks paddle constantly to resist the buoyant force of the body. Using video sequences from two orthogonal cameras we reconstructed the 3-dimensional motion of the feet through water and estimated the forces involved with a quasi-steady blade-element model. We found that during station holding, near the bottom, ducks use drag based propulsion with the webbed area of the foot moving perpendicular to the trajectory of the foot. The body was pitched at 76 +/- 3.47 degrees below the horizon and the propulsive force was directed 26 +/- 1.9 degrees ventral to the body so that 98% of the propulsive force in the sagittal plane of the duck worked to oppose buoyancy. The mechanical work done by moving both feet through a paddling cycle was 1.1 +/- 0.2 J which was equivalent to an energy expenditure of 3.7 +/- 0.5 W to hold position while feeding at 1.5 m depth. We conclude that in shallow water the high energetic cost of feeding in ducks is due to the need to paddle constantly against buoyancy even after reaching the bottom. The mechanical energy spent on holding position near the bottom, while feeding, is approximately 2 fold higher than previous estimates that were made for similar bottom depths but based on the presumed motion of the body instead of motion of the feet.
Keywords: Behavior; Sea Ducks - General

Dispersion and sexual maturity of Mergus octosetaceus Vieillot, 1817 in the Serra da Canastra, Minas Gerais, Brazil - Ribeiro, F.; Lins, L. V.; Gomes, V. M.; Nery, F. H.; dos Reis, E. S. (Revista Brasileira De Ornitologia, 2011)
Times Cited: 0 Ribeiro, Flavia Lins, Livia Vanucci Gomes, Vanessa Matos Nery, Flavio Henrique dos Reis, Edmar Simoes 0
Keywords: Dispersal; Brazilian Merganser; Mergus octosetaceus

Reproductive Ecology of the Brazilian Merganser (Mergus octosetaceus) in Serra da Canastra National Park and Adjacent Areas, Minas Gerais, Brazil - Ribeiro, F.; Lins, L. V.; Rodrigues, F. H. G. (WATERBIRDS, 2018)
The Brazilian Merganser (Mergus octosetaceus) is globally classified as a Critically Endangered species and is one of the world's rarest waterbirds. The breeding ecology of this species was studied between 2005 and 2016 in the region of the Serra da Canastra National Park, Minas Gerais, Brazil. Between two and six nests were followed each year, with mean of 4.1 (n = 18 nests). Mean clutch size was 6.7 +/- 0.9 (n = 31 clutches) with a range of five to eight eggs per nest. Average incubation constancy was 88.3% (n = 3 nests) and ranged from 86.7% to 90.7%. Mean incubation temperature and humidity were obtained from three nests and ranged from 33.6 degrees C to 33.8 degrees C and 65.9% to 70.2% respectively. The nest success was 77.1%, and the duckling survival (up to 8 weeks) was 53.8%. Nest predation was relatively low at 7.9%, and the annual reproductive output was 4.7 ducklings/female. Data on breeding ecology is fundamental in guiding conservation strategies, both in the field and in captivity.
Times Cited in Web of Science Core Collection: 1 Total Times Cited: 1 Cited Reference Count: 33
Keywords: ALASKA; CONSERVATION; Brazilian Merganser; Mergus octosetaceus; clutch size; EIDERS; breeding success; BREEDING BIOLOGY; HISTORY; incubation constancy; incubation rhythm; nest success

PCB exposure in sea otters and harlequin ducks in relation to history of contamination by the Exxon Valdez oil spill - Ricca, Mark A.; Miles, A. Keith; Ballachey, Brenda E.; Bodkin, James L.; Esler, Daniel; Trust, Kimberly A. (Marine Pollution Bulletin, 2010)
Exposure to contaminants other than petroleum hydrocarbons could confound interpretation of Exxon Valdez oil spill effects on biota at Prince William Sound, Alaska. Hence, we investigated polychlorinated biphenyls (PCBs) in blood of sea otters and harlequin ducks sampled during 1998. PCB concentrations characterized by lower chlorinated congeners were highest in sea otters from the unoiled area, whereas concentrations were similar among harlequin ducks from the oiled and unoiled area. Blood enzymes often elevated by xenobiotics were not related to PCB concentrations in sea otters. Only sea otters from the unoiled area had estimated risk from PCBs, and PCB composition or concentrations did not correspond to reported lower measures of population performance in sea otters or harlequin ducks from the oiled area. PCBs probably did not influence limited sea otter or harlequin duck recovery in the oiled area a decade after the spill. Published by Elsevier Ltd.
Keywords: Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Contaminants

Water Bird Migration near the Yukon Canada and Alaskan USA Coast of the Beaufort Sea 1. Timing Routes and Numbers in Spring - Richardson, W. J.; Johnson, S. R. (Arctic, 1981)
Radars, systematic visual observations from the coast and aerial surveys were used to study migration near the Yukon (1975) and Alaskan (1977-1978) coasts of the Beaufort Sea. Conspicuous eastward migration of loons, brant, seaducks, jaegers and glaucous gulls occurs along the icebound coast, and in the Yukon some eastbound species (especially brant) concentrate coastally. Overall, eastward migration is predominantly broad-front with little coastal concentration. Most eiders and perhaps most oldsquaws, the commonest waterbirds, fly east offshore where there is more open water. Westward migration is much less conspicuous visually; swans, geese and pintails are the main groups seen. However, radar shows extensive broad-front westward flights, probably largely of shorebirds. Most spring migration, both east and west, is from May 15th-June 20th, with the coastal peak (May 25th-June 15th) apparently being later than that offshore. Some coastal migrants land on river water that overflows onto nearshore ice in early June. Some waterbirds bypass the largely ice-covered Alaskan Beaufort by flying northeast across interior Alaska and/or northwestern Canada from the Pacific Ocean to the Canadian Arctic. These overland migrants include some yellow-billed and arctic loons, brant and jaegers; probably most Thayer's gulls; and probably some oldsquaws, Sabine's gulls, arctic terns and other species.
Keywords: Sea Ducks - General; Nonbreeding Seasons; Migration

Effects of clam species dominance on nutrient and energy acquisition by spectacled eiders in the Bering Sea - Richman, Samantha E.; Lovvorn, James R. (Marine Ecology Progress Series, 2003)
The spectacled eider Somateria fischeri, a 'threatened' species, winters in pack ice of the Bering Sea. In dives of 40 to 70 m for benthic invertebrates, the high energy costs of foraging are offset by high benthic biomass. However, there is evidence that the dominant clam prey has changed from Macoma calcarea to Nuculana radiata, perhaps adversely affecting the foraging energetics of the eiders. We studied effects of differences in nutrient and energy content, crushing resistance of shells, digestibility, gut retention time, areal density, shell length, and depth in the sediments on the relative foraging value of M. calcarea versus N. radiata. To avoid using a 'threatened' species for experiments, we used common eiders Somateria mollissima for digestion studies and white-winged scoters Melanitta fusca (the same size as spectacled eiders) for foraging studies. For the prey size range comprising 93% of the eiders' diet (18 to 30 mm), M. calcarea including shells was lower in ash, and higher in nitrogen, lipid, and energy, than N. radiata. Digestibility was 76% for M. calcarea versus 67% for N. radiata, but gut retention time did not differ. In a tensometer, crushing resistance was much higher for N. radiata than M. calcarea for shells 18 to 24 mm long, but did not differ for 24 to 30 mm because shells of N. radiata were often severely abraded. For scoters foraging on freshly thawed Macoma balthica buried in sand in an aquarium 1.8 m deep, intake (no. s-1) decreased by 31% when burial depth in the sediments was increased from 4 to 7 cm; most N. radiata are <4 cm deep, and most M. balthica eaten by eiders are probably 7 to 10 cm deep. Considering energy content, digestibility, and intake rates at these burial depths for 1200 clams m-2, energy assimilated was 14 to 19% higher for N. radiata than M. calcarea of the same length classes. However, larger M. calcarea yielded 58% higher intake of assimilable energy than smaller N. radiata. These patterns emphasize that relative foraging value depends strongly on size (age) structures of different prey populations, which vary with recruitment, growth, and mortality in different seasons and years. Our results show that impacts of long-term benthic change on eiders depend not only on shifts in total clam abundance, but also on species differences in digestibility, size structure, and size-dependent nutrient content and burial depth.
Keywords: Somateria fischeri; Spectacled Eider; Melanitta fusca; Nonbreeding Seasons; White-winged Scoter; Energetics and Nutrition; Trophic Interactions

Costs of diving by wing and foot propulsion in a sea duck, the white-winged scoter - Richman, S. E.; Lovvorn, J. R. (Journal of Comparative Physiology B Biochemical Systemic and Environmental Physiology, 2008)
Most birds swim underwater by either feet alone or wings alone, but some sea ducks often use both. For white-winged scoters (Melanitta fusca), we measured costs (V-O2) of dives to 2 m with descent by feet only versus wings + feet (only feet are used at the bottom). Dive costs repaid during the recovery period after a dive bout were an important fraction (27-44%) of total dive costs, and removing costs of extraneous surface behaviors increased resolution of differences between dive types. Scoters using wings + feet had 13% shorter descent duration, 18% faster descent speed, 31% fewer strokes/m, and 59% longer bottom duration than with feet only. The cost of time underwater for dives using wings + feet was 32-37% lower than with feet only (P = 0.09 to 0.15). When indirect methods were used to partition descent costs from costs of ascent and bottom phases, using wings + feet lowered descent cost by an estimated 34%. Thus, using wings + feet increases descent speed and lowers descent cost, leaving more time and energy for bottom foraging. For birds in cold water, the large savings may result from both biomechanical and thermoregulatory factors.
Keywords: Behavior; Melanitta fusca; White-winged Scoter; Energetics and Nutrition

Predator size, prey size and threshold food densities of diving ducks: does a common prey base support fewer large animals? - Richman, Samantha E.; Lovvorn, James R. (Journal of Animal Ecology, 2009)
P>1. Allometry predicts that a given habitat area or common prey biomass supports fewer numbers of larger than smaller predators; however, birds from related taxa or the same feeding guild often deviate from this pattern. In particular, foraging costs of birds may differ among locomotor modes, while intake rates vary with accessibility, handling times and energy content of different-sized prey. Such mechanisms might affect threshold prey densities needed for energy balance, and thus relative numbers of different-sized predators in habitats with varying prey patches.2. We compared the foraging profitability (energy gain minus cost) of two diving ducks: smaller lesser scaup (Aythya affinis, 450-1090 g) and larger white-winged scoters (Melanitta fusca, 950-1800 g). Calculations were based on past measurements of dive costs with respirometry, and of intake rates of a common bivalve prey ranging in size, energy content and burial depth in sediments.3. For scaup feeding on small prey < 12 mm long, all clams buried deeper than 5 cm were unprofitable at realistic prey densities. For clams buried in the top 5 cm, the profitability threshold decreased from 216 to 34 clams m(-2) as energy content increased from 50 to 300 J clam(-1).4. For larger scoters feeding on larger prey 18-24 mm long, foraging was profitable for clams buried deeper than 5 cm, with a threshold density of 147 m(-2) for clams containing 380 J clam(-1). For clams < 5 cm deep, the threshold density decreased from 86 to 36 clams m(-2) as energy content increased from 380 to 850 J clam(-1). If scoters decreased dive costs by swimming with wings as well as feet (not an option for scaup), threshold prey densities were 11-12% lower.5. Our results show that threshold densities of total prey numbers for different-sized ducks depend on prey size structure and depth in the sediments. Thus, heterogeneity in disturbance regimes and prey population dynamics can create a mosaic of patches favouring large or small predators. Whether a given area or total prey biomass will support greater numbers of larger or smaller predators will vary with these effects.
Keywords: Melanitta fusca; White-winged Scoter; Energetics and Nutrition; Trophic Interactions

Temporal and Spatial Patterns in the Abundance of Wintering Red-Breasted Mergansers Mergus-Serrator in an Estuary - Richner, H. (Ibis, 1988)
Tidal, temporal and spatial aspects in the abundance of wintering Red-breasted Mergansers in the Ythan estuary, northeast Scotland [UK], were investigated. The number and location of birds were examined in relation to four variables: tidal cycle and tidal range, and month and time of day. A significant increase in the numbers of this piscivorous bird occurred as the winter progressed. Numbers were highest in early morning and then decreased significantly during the day. Spring tides were favoured over neap tides and a significant increase in numbers was recorded between low tide and high tide. The lower part of the estuary was preferred over the upper part with no detectable shift in the preference occurring in relation to any of the four variables.
Keywords: Abundance, Distribution, and Trends; Nonbreeding Seasons; Mergus serrator; Red-breasted merganser

First report of typhlitis/typhlohepatitis caused by Tetratrichomonas gallinarum in three duck species - Richter, Barbara; Schulze, Christoph; Kaemmerling, Jens; Mostegl, Meike; Weissenboeck, Herbert (Avian Pathology, 2010)
Two Red-breasted Mergansers (Mergus serrator), one Hooded Merganser (Lophodytes cucullatus), and one Common Eider (Somateria mollissima) from a German zoological collection died of necrotizing typhlitis/typhlohepatitis within 2 years. Using a newly established chromogenic in situ hybridization assay, numerous intralesional trophozoites of Tetratrichomonas gallinarum could be detected in formalin-fixed and paraffin-embedded tissues from the caeca and livers of the affected birds. Partial sequencing of the 18S rRNA-gene revealed two unique nucleotide sequences very similar to T. gallinarum strains isolated from avian and human hosts. One turkey kept in the same zoological collection succumbed to histomonosis (blackhead disease) confirmed with chromogenic in situ hybridization at the time of the first duck fatalities. This turkey also harboured T. gallinarum trophozoites within necrotic cell debris in the caecal lumen, which might be epidemiologically related to the T. gallinarum infections in the ducks.
Keywords: Common Eider; Somateria mollissima; Disease; Mergus serrator; Red-breasted merganser; Hooded Merganser; Lophodytes cucullatus

Predation on Seabirds by Sea Otters - Riedman, M. L.; Estes, J. A. (Canadian Journal of Zoology, 1988)
Although rarely reported in the past, predation by sea otters (Enhydra lutris) on seabirds has been observed more frequently in the last decade. A total of 23 incidents of definite or probable predation on seabirds have been observed in California [USA] (20) and in Alaska at Amchitka Island (3). In California, the most commonly eaten species were western grebes, although cormorants, gulls common loons, and surf scoters were also consumed. All cases of seabird predation in California have occurred in the northern part of the sea otter's range in three locations: Point Lobos, Stillwater Cove, and the Monterey harbor area. When sex could be determined, most of the otters observed feeding on seabirds were adult males. At one site, it appeared that the same individual repeatedly captured birds. Predation on seabirds is indicative of the sea otter's ability to learn new and innovative foraging tactics, and is consistent with a high degree of individual variation in diet observed among sea otters in Monterey. Sea otters initially capture birds by diving and grabbing them from underwater while the bird rests on the surface, in a manner similar to that employed by coastal river otters to capture seabirds. When mink, freshwater-inhabiting otters, and sea otters are compared, a graded reduction in the tendency to eat birds appear to occur in the more aquatic mustelids, with the relative importance of birds in the diet being greatest in mink and least in sea otters.
Keywords: Nonbreeding Seasons; Melanitta perspicillata; Surf Scoter; Trophic Interactions

Foraging Effort and Pre-laying Strategy in Breeding Common Eiders - Rigou, Yves; Guillemette, Magella (Waterbirds, 2010)
To face energetic demands of reproduction, female birds need to build up body reserves before breeding and/or feed while producing eggs and incubating. Five female Common Eiders were implanted with data loggers that recorded flying and diving activity for a year. The pre-laying period, defined as the interval between the end of spring migration and laying of the first egg, extended over eleven to 27 days and represented a period of intense foraging activity. Daily time spent diving (DTSD) during the pre-laying period averaged 159.6 +/- 16.0 min compared to an annual average of 91.4 +/- 37.8 min. Diving decreased to 69.8 +/- 7.4 min during laying and became almost negligible at the onset of incubation. Females showed hyperphagic behavior during follicular growth, suggesting that they may directly utilize ingested food for egg production and laying. Given the small number of instrumented females, available evidence was reviewed on foraging and time of arrival in various populations and subspecies. Despite large variations in migration distance, the pre-laying period was similar to other populations (16-28 days), as well as DTSD (160-211 min). Reduced take-off capability may constrain the timing of accumulation of body reserves and foraging effort. Further, the level of body mass required for nesting (laying and incubation) was estimated to be 543 g higher than in winter, of which about 41-72% would be accumulated on the breeding grounds. Protection of foraging areas during the pre-breeding period is important to maintain healthy populations. Received 2 March 2009, accepted 19 March 2010.
Keywords: Behavior; Common Eider; Nonbreeding Seasons; Somateria mollissima; Energetics and Nutrition

Large-scale changes in marine and terrestrial environments drive the population dynamics of long-tailed ducks breeding in Siberia - Rintala, J.; Hario, M.; Laursen, K.; Moller, A. P. (SCIENTIFIC REPORTS, 2022)
Migratory animals experience very different environmental conditions at different times of the year, i.e., at the breeding grounds, during migration, and in winter. The long-tailed duck Clangula hyemalis breeds in the Arctic regions of the northern hemisphere and migrates to temperate climate zones, where it winters in marine environments. The breeding success of the long-tailed duck is affected by the abundances of predators and their main prey species, lemmings Lemmus sibiricus and Dicrostonyx torquatus, whose population fluctuation is subject to climate change. In the winter quarters, long-tailed ducks mainly eat the blue mussel Mytilus edulis. We examined how North-west Siberian lemming dynamics, assumed as a proxy for predation pressure, affect long-tailed duck breeding success and how nutrient availability in the Baltic Sea influences long-tailed duck population size via mussel biomass and quality. Evidence suggests that the long-tailed duck population dynamics was predator-driven on the breeding grounds and resource-driven on the wintering grounds. Nutrients from fertilizer runoff from farmland stimulate mussel stocks and quality, supporting high long-tailed duck population sizes. The applied hierarchical analysis combining several trophic levels can be used for evaluating large-scale environmental factors that affect the population dynamics and abundance of migrants from one environment to another.
Times Cited in Web of Science Core Collection: 0 Total Times Cited: 0 Cited Reference Count: 99
Keywords: CLIMATE-CHANGE; LIFE-HISTORY; PREY; BLUE MUSSELS; ARCTIC FOXES; BALTIC SEA; BRENT GEESE; LEMMING POPULATION; LIMIT-CYCLES; SNOW COVER

Do wintering Harlequin Ducks forage nocturnally at high latitudes? - Rizzolo, Daniel J.; Esler, Daniel; Roby, Daniel D.; Jarvis, Robert L. (Condor, 2005)
We monitored radio-tagged Harlequin Ducks (Histrionicus histrionicus) to determine whether nocturnal feeding was part of their foraging strategy during winter in south-central Alaska. Despite attributes of our study site (low ambient temperatures, harsh weather, short day length) and study species (small body size, high daytime foraging rates) that would be expected to favor nocturnal foraging, we found no evidence of nocturnal dive-feeding. Signals from eight radio-tagged Harlequin Ducks never exhibited signal loss due to diving during a total of 780 minutes of nocturnal monitoring. In contrast, the same eight birds exhibited signal loss during 62 +/- 7% (SE) of 5-minute diurnal monitoring periods (total of 365 minutes of monitoring). Our results suggest that Harlequin Ducks in south-central Alaska face a stringent time constraint on daytime foraging during midwinter. Harlequin Ducks wintering at high latitudes, therefore, may be particularly sensitive to factors that increase foraging requirements or decrease foraging efficiency.
Keywords: Behavior; Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus

Breeding Atlantic Puffins, Fractercula arctica, and other bird species of Coburg Island, Nunavut - Robards, Martin; Gilchrist, H. Grant; Allard, Karel (Canadian Field-Naturalist, 2000)
Coburg Island and neighbouring waters were recently designated a Canadian National Wildlife Area. The large seabird colony at Cambridge Point has been previously described, and is dominated by Thick-billed Murres (160 000 pairs). We found that a small offshore island, named Princess Charlotte Monument. also supported breeding populations of seven marine bird species; three of which did not breed at the main colony (i.e., Northern Fulmar, Common Eider, and Atlantic Puffin). This is the most northern confirmed breeding site for Atlantic Puffins in Canada. Puffins at both Coburg Island and northern Greenland nest in rock crevices, apparently because permafrost in soil prevents burrow nesting. We suggest that puffin populations in the high arctic maybe limited by habitat, rather than prey availability.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Common Eider; Somateria mollissima

Nuptial performance of the hooded merganser - Robb, Wallace Havelock (Auk, 1930)
A detailed description.
Keywords: Behavior; Hooded Merganser; Lophodytes cucullatus

Le Garrot d’Islande dans l’estuaire du Saint-Laurent : calendrier de présence annuelle, répartition, abondance, âge-ratio et sex-ratio. - Robert, M.; Benoit, R.; Marcotte, C.; Savard, J.-P. L.; Bordage, D.; Bourget, D. (Technical Report Series, 2003)
From 1997 to 2002, we studied the population of Barrow’s Goldeneye wintering in the St. Lawrence Upper and Lower Estuaries. Our goals were: to better assess the number of wintering goldeneyes in the estuary and to identify important concentration areas in mid-winter; to count goldeneyes on a weekly basis at selected sites throughout the winter and identify the areas used at these sites; to estimate population age and sex ratios; and to determine the seasonal use of the estuary by goldeneyes. To achieve these objectives, we carried out six helicopter surveys (three in January and February 1999, and three in January and February 2002) and 1484 ground surveys (in winter 1997-1998 and 1998-1999, and in Fall 2001). We also analysed the ÉPOQ and Christmas Bird Count databases. Ground surveys indicated that, in fall, the first Barrow’s Goldeneyes arrive on the south shore of the estuary during the first half of October and on the north shore, during the second half. Barrow’s Goldeneyes were present at some sites until the end of May. Goldeneyes were not found on the south shore of the estuary during the coldest winter months but were quite numerous in spring and fall. In contrast, large numbers of goldeneyes used the north shore of the estuary in January and February, the two coldest months. The mean monthly number of goldeneyes observed during ground surveys showed that Baie des Anglais (Baie-Comeau) and Baie-des- Rochers were by far the sites with the greatest concentrations of Barrow’s Goldeneyes. Up to 1020 and 604 birds were counted there, respectively. Other sites included, by order of importance, La Malbaie (max. 473 ind.), Anse à Mercier (315 ind.), Cap-à-l’Aigle (302 ind.), Franquelin (295 ind.), Baie du Ha! Ha! (500 ind.), and Baie Mitis (284 ind.). Barrow’s Goldeneyes were most numerous in Baie des Anglais during January and February. In Baie-des-Rochers and other north shore sites, they were abundant from December to April. Overall, the population was composed of 75% adults and 25% immatures. Male and female immatures were equally abundant. Among adults however, males were more numerous than females, accounting for 45% of the population compared to 30% only for females. The proportion of immatures increased in late spring from 29.5% in April to 44.6% in May, as adults departed for their breeding areas. During the six helicopter surveys, we counted an average of 2232 + 690 (SD) Barrow’s Goldeneyes, mainly (between 92.6% and 96.8% depending of the survey) on the north shore of the estuary. At most, only 1.2% (max. 54 ind.) of the birds was on the south shore of the estuary during a given survey and between 3.0% and 7.3% (max. 430 ind.) were around the islands of the estuary. The sites where we found most of the birds were: Baie-Comeau, Baie-Sainte-Catherine, Baie-des-Rochers, Cap-à-l’Aigle, Godbout, Petite-Romaine, Île aux Lièvres and La Malbaie. This study shows that the St. Lawrence Estuary is the major wintering area for the Eastern North American population of Barrow’s Goldeneyes, supporting over 50% of the population estimated at no more than 4,500 birds. It also shows that during the coldest parts of winter, Barrow’s Goldeneyes are restricted to the large intertidal areas of the north shore of the estuary as, because of prevailing winds and currents, intertidal areas of the south shore are covered by ice during that period. This study also revealed that, contrary to previous belief, Barrow’s Goldeneyes are nearly as numerous as Common Goldeneyes in the St. Lawrence Estuary in winter. However, both species have different distribution along the shores both at local and regional scales. We also showed that previous surveys did not provide a clear idea of the abundance of Barrow’s Goldeneyes in the St. Lawrence Estuary. We argue that the winter concentration of Barrow’s Goldeneyes in the estuary could be disastrous in the event of an oil spill, and that the species should be classified as of high priority within the Urgence Contigency Plan (Plan d’intervention d’urgence) of the Canadian Wildlife Service, Québec Region. On the other hand, this concentration should allow close monitoring of numbers and population structure. Our study provides a general overview of the Barrow’s Goldeneye population wintering in the St. Lawrence Estuary, but more detail studies are needed to identify the factors (i.e., microhabitats, food preferences) controlling the distribution of the species in the St. Lawrence corridor, so that the survival of this population can be assured.
Keywords: Habitat; SDJV funded; Bucephala islandica; Abundance, Distribution, & Trends; Nonbreeding season; Barrow’s Goldeneye

Relationship among breeding, molting, and wintering areas of male Barrow's Goldeneyes (Bucephala islandica) in eastern North America - Robert, Michel; Benoit, Rejean; Savard, Jean-Pierre L. (Auk, 2002)
Little is known of the eastern North American population of Barrow's Goldeneyes (Bucephala islandica), which was recently listed as "of special concern" in Canada. In 1998 and 1999, we marked 18 adult males wintering along the St. Lawrence River, Quebec, with satellite transmitters to document their breeding, molting, and wintering distribution and phenology, and to describe timing and routes of their spring, molt, and fall migrations. Thirteen males moved inland from the St. Lawrence River to breed; the spring migration averaged 5.9 days, and birds arrived on breeding areas on average 9 May. All breeding areas were inland, on the north shore of the St. Lawrence River estuary and gulf. Breeding areas averaged 64.8 km from the St. Lawrence corridor. Males stayed on their respective breeding area a mean of 34.5 days, and left on average 11 June. Twelve males were tracked to their molting areas, one of which stayed on its wintering area until 5 June and flew directly to its molting area. Their molt migration averaged 18.6 days, and the mean arrival date on molting areas was 30 June. All molting areas were located north and averaged 986 km from breeding areas. Four males molted in Hudson Bay, four in Ungava Bay, two in northern Labrador, one on Baffin Island, and one inland, near the Quebec-Labrador border. The mean length of stay on the molting areas was 105.3 days, and the mean date of departure from molting areas was 4 October. All goldeneyes for which the radio still functioned during fall migration returned to winter in the St. Lawrence River estuary, on average 6 November. Our results refute the idea that the main breeding area of the eastern North American population of Barrow's Goldeneyes is located in northern Quebec and Labrador and rather indicate that it is in the boreal forest just north of the St. Lawrence River estuary and gulf. They also indicate that Barrow's Goldeneye males undertake a genuine molt migration, and highlight the importance of molting areas because birds stayed there approximately four months each year.
Keywords: Breeding Season; Nonbreeding Seasons; Molt; Migration; SDJV funded; Barrow's Goldeneye; Bucephala islandica; Population Delineation

The breeding range of the Barrow's Goldeneye in eastern North America - Robert, Michel; Bordage, Daniel; Savard, Jean-Pierre L.; Fitzgerald, Guy; Morneau, Francois (Wilson Bulletin, 2000)
The breeding range of Barrow's Goldeneye (Bucephala islandica) is largely restricted to northwestern North America, and little is known of the small population that winters in eastern Canada. Based on weak evidence, this eastern population was thought to nest mainly in northern Labrador. Our May 1990 to 1998 surveys identified a breeding area in the forest regions of the Quebec Laurentian Highlands. We observed Barrow's Goldeneyes on 137 lakes and 5 rivers, of which 95.2% were along the north shore of the St. Lawrence estuary and gulf. The species was found mainly on small lakes (ltoreq 10 ha) at greater than 500 m elevation. Most occupied lakes (96.5%) were within 100 km of the St. Lawrence River and 48.9% of them were headwater lakes. Four broods observed in 1998 represent the first eastern North American documentation of breeding. By means of satellite telemetry, 5 of 7 males captured on the wintering grounds were relocated on the north shore of the St. Lawrence River in May, 60-140 km inland from the estuary and gulf. Each male spent 34-50 days at its respective site, presumably with a mate. The north shore of the estuary and gulf may be the core breeding area for Barrow's Goldeneyes wintering along the St. Lawrence River.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Habitat; Barrow's Goldeneye; Bucephala islandica

Summer food habits of Harlequin Ducks in eastern North America - Robert, Michel; Cloutier, Louise (Wilson Bulletin, 2001)
We collected feces of breeding Harlequin Ducks (Histrionicus histrionicus) from interior rivers of Northern Quebec, Labrador and Newfoundland to document their summer food habits. We obtained 42 samples from 50 ducks. All samples contained recognizable food items, and the mean number of taxa identified per sample was 3.6 (SD = 1.6, range = 1-7). Overall, a total of 10,222 organisms from 25 taxa were identified. Nearly all (99.7%) food items were insects; the rest were mollusks and mites. Among insects, Simuliidae larvae were the most common food item, representing 87.2% of all prey counted. Other insects had low relative frequencies, the highest being Trichoptera with only 8.0%. However, in terms of frequency of occurrence, many insects were well represented: Trichoptera (83.3%), Ephemeroptera (64.3%), Diptera (61.9%), Plecoptera (33.3%), Coleoptera (11.9%), and Heteroptera (9.5%). Although Simuliidae larvae may represent the most important food taken in terms of absolute numbers, the relative importance of Trichoptera may be much higher in terms dry weight. These results are consistent with observations that Harlequin Ducks usually feed on the bed of fast stretches of rivers, and occasionally in slow-moving waters.
Keywords: Breeding Season; Harlequin duck; Histrionicus histrionicus; Trophic Interactions

Effects of backpack radio-transmitters on female Barrow's Goldeneyes - Robert, Michel; Drolet, Bruno; Savard, Jean-Pierre L. (Waterbirds, 2006)
We compared time-budgets and return rates of breeding female Barrow's Goldeneyes (Bucephala islandica) fitted, or not, with transmitters attached with backpack harnesses in 2001-2004 in southern Quebec. We compared the mean proportion of time devoted to feeding, locomotion, alert, resting, preening, and maintenance (i.e., resting Plus preening) by females observed >= 200 min. Females with backpacks (N=5) spent significantly less time feeding (x SE: 25 +/- 5% versus 43 +/- 3%) and more time in maintenance activities (51 +/- 6% versus 31 +/- 4%) than females without transmitters (N=6). Mean time devoted to other behavior did not differ significantly. Upon release, females appeared disturbed with the backpack, actively bathing, preening and/or flapping wings. Of the females with transmitters observed >= 200 min, three spent 4%, 8%, and 57% of their preening time at their transmitter, antennae or harness. None of the 16 females harnessed in 2001-2003 were recaptured in nest boxes or seen again on the study area in 2002-2004. For comparison, 66% of adult female Barrow's Goldeneyes captured in nest. boxes and marked with leg bands in 2000-2002 were recaptured or seen again in subsequent years. We do not recommend the rise of harnesses on diving ducks and sea ducks as it may affect their behavior and survival, at least for birds wintering in areas where conditions are severe.
Keywords: Behavior; Breeding Season; Techniques; SDJV funded; Barrow's Goldeneye; Bucephala islandica

Habitat features associated with Barrow's Goldeneye breeding in eastern Canada - Robert, Michel; Drolet, Bruno; Savard, Jean-Pierre L. (Wilson Journal of Ornithology, 2008)
We investigated environmental variables linked to presence of Barrow's Goldeneye (Bucephala islandica) pairs from the eastern North American population on 412 lakes of the Sainte-Marguerite River watershed, Quebec, Canada. We analysed habitat relationships at two spatial scales (i.e., considering all lakes surveyed and high elevation lakes only) and predetermined the high elevation lakes as those including 90% of Barrow's Goldeneye occurrences. Barrow's Goldeneye were found on 59 lakes, all of which were >= 490 m elevation (maximum = 822 m) with 90% at >= 610 m. Six variables tested using multivariate logistic regressions contributed to explain the occurrence of goldeneyes. Four were significant (P < 0.10) in both the complete and the high elevation data sets: nest boxes (+) and brook trout (Salvelinus fontinalis) (-) occurrences, altitude (+), and the interaction between altitude and mean slope (+). The models explained only a small proportion of Barrow's Goldeneye occurrence for both data sets (R-2 = 0.27 and 0.23, respectively). The negative relationship between Barrow's Goldeneye and brook trout occurrences, and the positive relationship with altitude probably reflect a positive relationship between goldeneye and highly productive aquatic ecosystems. Barrow's Goldeneye from eastern North America primarily use high altitudinal, productive lakes during the breeding season, which emphasizes the importance of fishless lakes for that population at risk.
Keywords: Breeding Season; Trophic Interactions; Habitat; Barrow's Goldeneye; Bucephala islandica

New Insights on Harlequin Duck Population Structure in Eastern North America as Revealed by Satellite Telemetry - Robert, Michel; Mittelhauser, Glen H.; Jobin, Benoit; Fitzgerald, Guy; Lamothe, Pierre (Waterbirds, 2008)
In order to better delineate affiliations between breeding, molting, and staging areas of the small Harlequin Duck (Histrionicus histrionicus) population wintering in eastern North America, in April 2001 satellite transmitters were implanted in eight adult males at Isle an Haut, Maine, a major wintering area for this population. Two birds were confirmed breeding on rivers on the Gaspe Peninsula, Quebec, two birds molted in northern Labrador, and four birds migrated to southwestern Greenland during the molting season, including one bird that bred in Quebec. The four birds tracked to southwestern Greenland likely molted there, although molting could be confirmed for only one bird. All birds tracked to Greenland, to breeding areas, and to molting locations returned to wintering sites in Maine the following wintering season. This study is the first confirmation of wintering male Harlequin Ducks from eastern North America molting in Greenland.
Keywords: Breeding Season; Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Population Delineation

The St. Lawrence River Estuary and Gulf: A stronghold for Barrow's Goldeneyes wintering in eastern North America - Robert, Michel; Savard, Jean-Pierre L. (Waterbirds, 2006)
From 1997 to 2005, the distribution, seasonal abundance, and age and sex ratios of wintering Barrow's Goldeneyes (Bucephala islandica) was documented in the St. Lawrence River Estuary and Gulf, Canada, with a combination of ground and helicopter surveys. Ground surveys showed that Baie-Comeau and Baie-des-Rochers were the most important localities, with monthly averages of 250 (max. = 1020) and 273 (604) individuals, respectively, from November through April. Helicopter surveys showed that four areas (Baie-Comeati, Baie-des-Rochers, Baie-Sainte-Catherine and La Malbaie/Cap-a-l'Aigle) harboured on average 74% of all Barrow's Goldeneyes in the estuary, that numbers of individuals were more stable at these sites, and that the distribution of Common Goldeneyes (Bucephala clangula) within the estuary differed from that of Barrow's Goldeneyes. Because of ice conditions, goldeneyes were not found on the south shore of the estuary during the coldest winter months, although they were quite numerous in spring and fall. In contrast, large numbers of goldeneyes used the north shore of the estuary all winter long and through the end of April. In January-February of 1999, 2002 and 2005, helicopter surveys (N = 8) yielded on average 2428 Barrow's Goldeneyes (CV = 8%), 2503 Common Goldeneyes (6%) and 1320 Red-breasted Mergansers (Mergus serrator, 70%) per year in the estuary. These species averaged 2087 (CV = 81%), 2214 (41%) and 2898 (34%) individuals/year, respectively, in the gulf in January-February of 2002 and 2005 (N = 3). Helicopter survey results indicated possible identification errors between these three species, stressing the need to survey them concurrently. The January-February ratio of adult males and 'brown heads' was greater in 1998 (57.0%) that) it) 1999 (51.8%), partly because there were more immatures in the population in 1999 (18.1 %) than in 1998 (10.2%). Adult sex ratios were significantly different from 1/1 in January-February of 1998 (P < 0.0001) and 1999 (P = 0.0072), whereas immature sex ratios were not (P >= 0.27). The monthly proportion of immatures increased between January and May of 1998 (P < 0.0001) and 1999 (P < 0.0001), because of adults departing for breeding areas. The eastern North American wintering population of Barrow's Goldeneyes may include a maximum of 6187 individuals, of which > 90% would winter along the St. Lawrence Estuary and Gulf. Thus, the St. Lawrence corridor should undoubtedly be considered as the winter stronghold for Barrow's Goldeneyes in eastern North America.
Keywords: Abundance, Distribution, and Trends; Nonbreeding Seasons; SDJV funded; Barrow's Goldeneye; Bucephala islandica

Characteristics of nest cavities of Barrow's Goldeneyes in eastern Canada - Robert, Michel; Vaillancourt, Marie-Andree; Drapeau, Pierre (Journal of Field Ornithology, 2010)
Barrow's Goldeneyes (Bucephala islandica) are secondary cavity nesters found in western North America and, to a lesser extent, in eastern North America. The eastern North American population is concentrated in the province of Quebec and totals about 2000 pairs. Characteristics of nest cavities used by Barrow's Goldeneyes have been described in western North America, but no nest cavities have been found in eastern North America. From 2004 to 2008, we searched for nest cavities in the species' core breeding area in the boreal forests north of the St. Lawrence River. We captured 12 adult females on their breeding grounds and fitted them with transmitters, but none apparently nested so we conducted ground searches in areas near lakes where paired birds were observed. We found 11 cavities, with 10 in dead, decaying trees and one in the dead part of a dying tree. Nine cavities were in white birch (Betula papyrifera) trees. Mean cavity height was 3.5 +/- 1.6 (SD) m (range = 1.2-6.6 m) and mean diameter at breast height (DBH) of cavity trees was 37.8 +/- 4.7 cm (range = 32.2-47.5 cm). In contrast to the population in western North America, Barrow's Goldeneyes in eastern North America appear to rely on the availability of natural cavities formed in large, decaying trees for nesting. Current forestry regulations in Quebec do not promote the retention of either large trees or older forests, reducing the availability of potential nest cavities for Barrow's Goldeneyes and likely threatening their long-term conservation. Therefore, we recommend that guidelines be developed to promote silvicultural practices aimed at preserving the long-term availability of large (DBH >= 30 cm) decaying trees across the breeding range of Barrow's Goldeneyes.
Keywords: Breeding Season; Habitat; Barrow's Goldeneye; Bucephala islandica

Sample size considerations for satellite telemetry and animal distributions - Roberts, A.; Silverman, E.; Gifford, S. (JOURNAL OF WILDLIFE MANAGEMENT, 2018)
Satellite telemetry is a powerful tool used to follow animals through their annual life cycle, informing the understanding of behavior and distribution of many species. Because boreal- and arctic-nesting North American sea duck populations are challenging to survey, satellite telemetry is important for describing breeding distributions and identifying breeding population structure. Accurate knowledge of breeding distributions is needed for effective habitat and harvest management, but satellite telemetry is expensive so it is important to consider the effort necessary to accurately map breeding distributions. We construct 3 theoretical breeding distributions using existing telemetry data from 3 species of sea ducks, Barrow's goldeneye (Bucephala islandica), surf scoter (Melanitta perspicillata), and black scoter (M. americana), by fitting kernel densities to approximate breeding locations of individual birds. Then we determined the minimum sample size needed to approximate these theoretical breeding distributions by assessing the overlap between breeding densities simulated by sampling from the distributions and the theoretical breeding densities. Diminishing information gains with additional effort (i.e., <1-5% improvement in prediction) were reached with sample sizes ranging from 80 to 130. Sea duck mortality, transmitter failure, and exclusion of non-breeding individuals resulted in an effective sample size smaller than the number of birds originally marked. For the cases we considered, obtaining breeding locations for 80-130 individuals would require marking 11-41% more birds than the sample size goal. Thus, although satellite telemetry provides valuable information on sea duck populations, our analysis suggests that accurately estimating the extent and relative use of breeding habitats requires substantial investment. (c) 2018 The Wildlife Society. Satellite telemetry is important to describe breeding distributions and to consider the effort needed to accurately map breeding distributions. We constructed breeding distributions using existing telemetry data then determined the minimum sample size needed to approximate distributions. Sample sizes needed were 80-130 individuals and would require over-marking by 11-41%.
Times Cited in Web of Science Core Collection: 3 Total Times Cited: 4 Cited Reference Count: 22
Keywords: sea ducks; Melanitta perspicillata; MOVEMENTS; Bucephala islandica; Melanitta americana; satellite telemetry; HABITAT USE; SEA; SPACE; black scoter; Barrow's goldeneye; surf scoter; SOUTHERN NEW-ENGLAND; breeding distribution; CONNECTIVITY; sample size

Role of Benthic Substrate in Waterbird Distribution on Great Salt Lake, Utah - Roberts, A. J.; Conover, M. R. (Waterbirds, 2014)
Benthic substrate has a large impact on aquatic plant and invertebrate assemblages and likely directly or indirectly influences waterbird distributions. The association of birds with various substrates can be important in survey design or habitat management. Northern Shoveler (Anas clypeata), Common Goldeneye (Bucephala clangula), Eared Grebe (Podiceps nigricollis), Ring-billed Gull (Larus delawarensis) and California Gull (L. californicus) densities on the hypersaline Great Salt Lake, Utah, were estimated to determine the association of bird distributions with benthic substrates. Three of the four groups of species monitored had densities that varied by benthic substrate; gulls were the exception. Eared Grebes occurred at the highest densities over calcareous reef-like structures known as bioherms, either as a result of ideal water depths for foraging or greater prey densities, than over other substrates. The highest densities of Northern Shovelers and Common Goldeneyes were observed Over mud substrates. This was likely due to mud being common near freshwater inflow sites and in lower salinity bays, areas waterfowl concentrate in because of the lower osmoregulatory demands compared to more pelagic areas of the Great Salt Lake. Knowing the relationship between waterbird densities and substrate will help managers estimate avian populations on hypersaline lakes.
Roberts, Anthony J. Conover, Michael R.
Keywords: Bucephala clangula; Common Goldeneye; Habitat; Abundance, Distribution, & Trends; Nonbreeding season

ENVIRONMENTAL INFLUENCES ON WINTERING DUCK ABUNDANCE AT GREAT SALT LAKE, UTAH - Roberts, A. J.; Conover, M. R.; Vest, J. L. (Western North American Naturalist, 2016)
North American waterfowl winter throughout a large geographic area, and the choice of wintering site has a direct impact on survival and fitness. Climatic and food variables are the most commonly cited factors influencing abundance and distribution of wintering migratory birds, including waterfowl. We conducted stratified aerial surveys at a northern latitude wintering site, Great Salt Lake (GSL), Utah, to describe the importance of this wintering area and to examine the influence of weather and food on the abundance of total ducks, Northern Shovelers (Anas clypeata), and goldeneye species (Bucephala spp.). Surveys indicated that up to 270,000 ducks use the GSL during winter, making it an important wintering area in the Pacific Flyway. Peak abundance of total ducks was positively correlated with overwinter temperatures. Northern Shoveler abundance was positively correlated with elevation of the GSL; higher lake elevation indicated more open water and hence more overwintering habitat. Goldeneye abundance was correlated with the continental population of the species and food abundance. All models had moderate fit (r(2) > 0.40). The GSL is unique in the United States as it is a large body of water where consistent ice cover does not occur and foraging habitat is available to ducks throughout winter. Our results suggest that ambient temperature and habitat availability are primary factors in the abundance of total wintering waterfowl, though food abundance seemed to influence wintering population size of individual duck species. We hypothesize that ducks endure the cold, hypersaline conditions on the GSL to exploit the abundant food supply and remain close to primary breeding regions.
Roberts, Anthony J. Conover, Michael R. Vest, Josh L.
Keywords: Bucephala clangula; Common Goldeneye; Habitat; Bucephala islandica; Nonbreeding season; Barrow’s Goldeneye

Factors affecting nest site selection and nesting success in the Common Eider Somateria mollissima - Robertson, Gregory J. (Ibis, 1995)
Nesting site selection and nesting success in Common Eiders Somateria mollissima were studied over a 3-year period (1991-1993) in the Mast River delta (58 degree 24'N, 94 degree 24'W), 40 km east of Churchill, Manitoba, Canada. Eiders preferentially nested on islands that had incubating Lesser Snow Geese Anser caerulescens caerulescens on them; this effect was also seen between years on the same islands. Eiders which nested on islands with geese had a reduced chance of having eggs taken by predators during egg-laying and had a greater chance of hatching once incubation had begun, independent of the number of other eiders nesting on the island. The distance to a goose nest was less in nests which did not lose eggs prior to incubation than in those which did, but there was no difference in the distance to a goose nest in eider clutches which did or did not hatch. Artificial eider eggs placed closer to goose nests had a lower probability of being predated than those placed farther away. Nests on islands farther up the river and farther from the mainland had higher nesting success, presumably because these nesting islands were inaccessible to Arctic Foxes Alopex lagopus.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Productivity; Habitat

Annual variation in common eider egg size: Effects of temperature, clutch size, laying date, and laying sequence - Robertson, Gregory J. (Canadian Journal of Zoology, 1995)
Annual variation in volumes of eggs laid by common eiders (Somateria mollissima sedentaria) nesting at La Perouse Bay, Manitoba (58 degree 43'N, 93 degree 27'W), was studied over 3 years (1991-1993). Temperatures during the egg-laying period were higher in 1991 than in 1992 and 1993. However, the eiders began nesting in 1993 at the same time as in 1991, whereas in 1992 the eiders began laying approximately 2 weeks later. Eiders laid significantly smaller clutches in 1992 than in the other 2 years. Egg size did not correlate with clutch size or laying date in any year. However, eiders laid smaller eggs in 1992 and 1993 than in 1991. In five egg clutches, the pattern of intraclutch egg-size variation was different among years. The last laid eggs of five egg clutches were disproportionately smaller in 1992 and 1993 (cold years) than those laid in 1991. Minimum daily temperatures before the egg-laying period (during rapid yolk development) were positively correlated with egg size. However, this effect was not significant when year and egg sequence were controlled for. Egg-size variation was correlated with the overall ambient temperatures during the laying period, whereas annual clutch-size variation was correlated with laying date, suggesting that the proximate mechanisms affecting clutch and egg size are different.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Productivity; Physiology

Egg adoption can explain joint egg-laying in common eiders - Robertson, Gregory J. (Behavioral Ecology and Sociobiology, 1998)
Hypotheses regarding the evolution and maintenance of intraspecific nest parasitism were tested with data collected during a 3-year study of common eiders (Somateria mollissima) breeding near Churchill, Manitoba. The nest parasitism rate was highest (42.4% of nests) during the year with the highest nest density and the best environmental conditions, and lowest (20.2% of nests) in the year with the lowest nest density and the poorest environmental conditions. Over the nesting season, parasitic eggs were laid at the same time as normally laid eggs. Most parasitic eggs (>75%) were laid before the host female laid her third egg. The majority of the parasitic eggs were the first or second egg produced by the parasitic female. When a parasitic egg was laid before or on the same day as the host female initiated her clutch, the probability of her first egg being depredated before incubation was significantly lowered. First- and second-laid eggs suffered a high rate of predation probably because nesting females do not attend their clutch until their second or third egg is laid. Hypotheses that some females use intraspecific nest parasitism to parasitize the parental care of other females were inconsistent with these data. Egg adoption is a likely explanation for the prevalence of females incubating parasitic eggs in this population.
Keywords: Behavior; Breeding Season; Common Eider; Somateria mollissima

Using Winter Juvenile/Adult Ratios as Indices of Recruitment in Population Models - Robertson, Gregory J. (Waterbirds, 2008)
There is an increasing interest in using winter juvenile counts as indices of recruitment in species that show delayed plumage maturation, especially for species, such as dispersed breeders, for which it is difficult to obtain good productivity estimates. To date, however, the needed mathematical work to assist in interpreting these winter juvenile/adult ratios has not been conducted. A matrix-based population model is presented that is modified to allow the fecundity component to be measured ill mid- to late winter. This model is simplified to a set of equations that relate adult survival, winter juvenile/adult ratios and population growth rates, allowing all assessment of population trend with only one survival rate and age ratio data. These models have the advantage of not requiring that age of first breeding be well known. As all example, age ratios and survival rates of Harlequin Duck (Histrionicus histrionicus) populations in British Columbia and Maine are presented. Models for both populations suggest recruitment of young is insufficient to compensate for adult mortality, which is contrary to observed trends. Although some further methodological work is needed, such as better estimates of true adult survival and a further understanding of how to obtain unbiased estimates of juvenile/adult ratios, these models may prove to be a useful tool to assess population trends when detailed demographic data are not available.
Keywords: Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Productivity; Population Dynamics; Population Model; Sea Ducks

Common Eider and large gull nesting associations in coastal Labrador - Robertson, G. J.; Chaulk, K. G. (ARCTIC SCIENCE, 2017)
Apparent nesting associations between avian egg predators and their prey have received much interest, with gulls and waterfowl receiving considerable attention. We examined the co-occurrence of breeding large gulls (Herring Gull (Larus argentatus Pontoppidan, 1763) and Great Black-backed Gull (Larus marinus L., 1758)) and Common Eiders (Somateria mollissima L., 1758) along the coast of Labrador from 1998 to 2003. Nest counts for large gulls and eiders were undertaken by ground crews on 45-109 islands each year, counting 79-283 and 721-3424 nests annually, respectively. Gulls were more likely to nest on an island with nesting eiders (69.4%) than without nesting eiders (38.4%), and the probability and numbers of gulls nesting on an island increased as eider colony size increased. Large gulls were 1.76 times more likely to occupy islands that had nesting eiders in the previous year, while eiders were equally likely to colonize islands that did or did not have nesting gulls in the previous year. Eiders were no more likely to abandon islands that had nesting gulls in the previous year. In subarctic coastal landscapes, large gulls appear to preferentially nest in association with nesting eiders, while eiders appear not to avoid nesting islands based on the previous presence of large gulls.
Times Cited in Web of Science Core Collection: 1 Total Times Cited: 1 Cited Reference Count: 40
Keywords: Common Eider; Herring Gull; SOMATERIA-MOLLISSIMA; POPULATION; ECOLOGY; PREDATION; Labrador; BAY; BLACK-BACKED GULLS; HERRING-GULLS; SITE SELECTION; BELCHER ISLANDS; COLONIES; colony site dynamics; Great Black-backed Gull

Intraclutch egg-size variation and hatching success in the common eider - Robertson, Gregory J.; Cooke, Fred (Canadian Journal of Zoology, 1993)
Intraclutch egg-size variation and hatching success were studied in a population of Hudson Bay common eiders (Somateria mollissima sedentaria) at La Perouse Bay, Manitoba (58 degree 24'N, 94 degree 24'W), to test the hypothesis that females allocate more nutrient reserves to eggs that are more likely to hatch. Egg volumes were calculated for 575 known-sequence eggs in 134 complete clutches of 3-6 eggs. In general, the length of eggs decreased linearly with position in the laying sequence, whereas the breadth of eggs followed a curvilinear pattern, the second or third egg being the widest. For all clutch sizes, the last-laid egg was the smallest and the second- or third-laid egg the largest. Hatching success also varied with position in the laying sequence. Pre-incubation failure declined over the laying sequence, whereas hatching failure (dead, infertile, or rotten eggs) increased. In all cases pre-incubation failure was the major cause of egg loss (84% of total loss). Overall, third and fourth eggs were the most successful and first eggs were the least successful. With one exception, successful and unsuccessful eggs were the same size within a laying sequence. We conclude that there is no clear relationship between egg size and hatching success, and that laying sequence per se has a greater effect on hatching success. Female eiders do not appear to allocate more reserves to eggs that are most likely to hatch, and we consider other proximate, physiological mechanisms to explain the observed pattern of intraclutch egg-size variation.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Productivity; Physiology

Winter philopatry in migratory waterfowl - Robertson, Gregory J.; Cooke, Fred (Auk, 1999)
Philopatry in migratory species can apply to any location used during the annual cycle. The degree of philopatry influences the genetic structure of populations, but only at the stage of the annual cycle when pair formation and gene exchange occur. Because pair formation in birds typically occurs during the breeding season, most studies have focused on breeding-site philopatry. Waterfowl (Anseriformes) are an important exception to this pattern because pair formation often occurs during the winter months. Yet, surprisingly few studies have examined winter philopatry in waterfowl. To serve as an impetus for future research, we summarize published information on winter philopatry in waterfowl and examine these patterns in light of current hypotheses proposed to explain philopatric behavior. Our analyses indicate that geese, swans, and sea ducks show high levels of winter philopatry, with homing rates varying between 49 and 98% to small study areas. In contrast, return rates (0 to 20%) and homing rates (35 to 85%) to large study areas probably are comparatively lower for dabbling ducks and pochards. Unfortunately, detailed comparisons among groups are hindered by variation in the scale at which philopatric behavior is evaluated (ranging from <1 km2 to 105 km2), and by confounding of return rates with homing rates. Future studies of winter philopatry would benefit by the adoption of a more standardized methodology. Many of the hypotheses proposed to explain breeding philopatry apply equally well to winter philopatry. In particular, both genetic and ecological mechanisms may play a role in the evolution of philopatry to the wintering ground. Additional field studies are needed to test these hypotheses, and we suggest future directions for a more detailed examination of this neglected area of research.
Keywords: Sea Ducks - General; Nonbreeding Seasons; Dispersal; Population Delineation

The timing of arrival and moult chronology of Harlequin Ducks Histrionicus histrionicus - Robertson, G. J.; Cooke, F.; Goudie, R. I.; Boyd, W. S. (Wildfowl, 1997)
The timing of arrival and moulting chronology of a population of post-breeding Harlequin Ducks was studied over a three year period in south-western British Columbia. Males first arrived on the moulting and wintering grounds in mid-June and most had returned from the breeding areas by the end of July. Females first arrived in late July and continued to arrive until the end of September The flightless period for the mates ranged from late July to late August. Flightless females could be seen throughout August and September. Wings took 30-31 days to regrow, compared to 26 days for tails. Assuming birds can fly at 70% remex growth this corresponds to a flightless period of about 21 days. Yearlings of both sexes exhibited moulting chronologies similar to adult males. All birds initiated moulting as soon as they arrived on the non-breeding grounds, suggesting an advantage for early moulting. The reasons for this are likely to be different for the two sexes. Males probably initiate moult quickly to be able to return to their alternate plumage and begin courting females. Females may moult early to complete wing growth before the onset of winter.
Keywords: Behavior; Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Molt

Moult speed predicts pairing success in male harlequin ducks - Robertson, Gregory J.; Cooke, Fred; Goudie, R. Ian; Boyd, W. Sean (Animal Behaviour, 1998)
The bright plumage of male ducks in sexually dichromatic species is thought to have evolved through intense sexual selection. This study examined the relationship between the timing and speed of moult into this bright plumage and subsequent mating success of male harlequin ducks, Histrionicus histrionicus. Males that moulted relatively slowly had a lower chance of establishing a pair bond than others. The timing of moult was unrelated to whether a male obtained a mate. Moult speed and timing were not correlated within individual males, but were significantly repeatable in individual males over 2 years. Moult speed probably reflects the condition of males, whereas timing of moult is more likely to be related to the distance to an individual's breeding area, which determines the timing of arrival to the moulting grounds. In waterfowl species that have been studied, males usually form dominance hierarchies before pairing and females tend to choose dominant males. We suggest that male harlequin ducks that moult slowly are poor-quality individuals, which are relegated to subordinate status and are unlikely to attract a mate the following autumn.
Keywords: Behavior; Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Molt

The timing of pair formation in Harlequin ducks - Robertson, Gregory J.; Cooke, Fred; Goudie, R. Ian; Boyd, W. Sean (Condor, 1998)
The timing of pair formation varies within and among species of ducks. In this study we documented the chronology of pair formation in a population of wintering Harlequin Ducks (Histrionicus histrionicus) in southwestern British Columbia. Harlequin Ducks began forming pair bonds in October and over half of the females were paired by December. This timing is much earlier than other ducks of similar size. A segment of this population was individually marked, and we documented the reunion of mates in subsequent years. In all cases where both members of the pair returned to their wintering grounds they reunited in the fall. New pair bonds, involving young males and females, were formed in the spring. We suggest that pair reunion in this species reduces the costs of courtship and pair bond maintenance and allows males to pair early in the nonbreeding season, compared to other species.
Keywords: Behavior; Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus

Spacing patterns, mating systems, and winter philopatry in Harlequin Ducks - Robertson, Gregory J.; Cooke, Fred; Goudie, R. Ian; Boyd, W. Sean (Auk, 2000)
Many species of waterfowl form pair bonds during the nonbreeding season, yet current descriptions of mating systems and patterns of philopatry in waterfowl focus on the breeding grounds. We studied wintering Harlequin Ducks (Histrionicus histrionicus) in southwestern British Columbia to examine mating systems and philopatric behavior outside of the breeding season. The number of males at our study area was far more variable than that of females. Males that were unsuccessful in obtaining a mate were observed over a larger area than were paired males. Habitat use overlapped considerably among paired males, and no territorial boundaries were formed. Annual return rates to the nonbreeding grounds were high for both sexes (62% for females, 77% for males). Individuals not only returned to the general study area, but also to specific sections within the study area. Males that did not pair in the previous year returned to the study area in the subsequent year with the same frequency as males that had obtained mates; however, they tended to leave the study area prior to courtship. Therefore, it is possible that males return to the same wintering grounds each year to reunite with a previous mate. High levels of philopatry by both sexes allow pairs to reunite in fall, potentially increasing the benefits of philopatry for both sexes.
Keywords: Behavior; Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Dispersal

Evidence of population declines among common eiders breeding in the Belcher Islands, Northwest Territories - Robertson, Gregory J.; Gilchrist, H. Grant (Arctic, 1998)
Information regarding the status of common eiders Somateria mollissima breeding in the Canadian Arctic is sorely lacking. In 1997, we surveyed five island archipelagoes in the Belcher Islands in Hudson Bay (56degree00'-57degree30'N, 79degree30'-80degree00'W) from 3 to 23 July. Our results were compared with eider surveys of the same islands completed between 1985 and 1989 using a standard protocol. We found 1416 eiders on 431 islands. Most (94.1%) were found while the female was still incubating. In all five island groups surveyed, the number of nesting eiders declined significantly (overall decline of 75.0% from 1985 - 88 to 1997, range: 62.3-84.0%). In 1997, nesting islands and adjacent waters were free of ice, and eiders nested early and laid large clutches (range: 4.0-4.4 +- 1.0-1.2 SD). These conditions indicate a good nesting season, and we inferred that extensive nonbreeding by female eiders in 1997 did not account for the observed decline. A large reported die-off of eiders during the winter of 1991-92, which occurred when areas of open water froze, was the most likely cause of the decline. Our results raise serious conservation concerns, because eider populations are sensitive to reductions in adult survival and this population is harvested throughout the year by subsistence hunters.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Common Eider; Somateria mollissima

Wintering Snowy Owls feed on sea ducks in the Belcher Islands, Nunavut, Canada - Robertson, Gregory J.; Gilchrist, H. Grant (Journal of Raptor Research, 2003)
Keywords: Common Eider; Nonbreeding Seasons; Clangula hyemalis; Long-tailed Duck; Somateria mollissima; Trophic Interactions

Morphological Variation among Harlequin Ducks in the Northwest Atlantic - Robertson, Gregory J.; Mittelhauser, Glen H.; Chubbs, Tony; Trimper, Perry; Goudie, R. Ian; Thomas, Peter W.; Brodeur, Serge; Robert, Michel; Gilliland, Scott G.; Savard, Jean-Pierre L. (Waterbirds, 2008)
Harlequin Ducks (Histrionicus histrionicus) were captured and measured at a variety of staging, breeding, molting and wintering sites across their Northwest Atlantic range from 1996-2002. The consistency in the body measurements taken oil the same birds across time and sites, as indexed by repeatability, was adequate (0.4-0.75), with the notable exception of total tarsus, which showed poor repeatability. Correlations among morphological measurements; were weak within each sex. Some differences among locations were detected, notably in wing length, with birds breeding in Labrador showing longer wings than birds breeding further south and those wintering in Maine. Overall, however, major differences among sites were not apparent. Recent satellite and banding information indicate that. many of these locations are linked and these observations are supported by this morphological data. Harlequin Ducks are similar to other ducks (except ciders) in that they are wide ranging and have disjunct populations, but show. at best, weak morphological differentiation across their range.
Keywords: Breeding Season; Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Physiology; Population Delineation

Clutch, egg and body size variation among common eiders breeding in Hudson Bay, Canada - Robertson, Gregory J.; Reed, Austin; Gilchrist, H. Grant (Polar Research, 2001)
The Hudson Bay common eider (Somateria molissima sedentaria) is a unique subspecies of eider that remains within the confines of Hudson Bay throughout the year. We compared clutch, egg and body size variation among populations of common eiders breeding in eastern and western Hudson Bay. Clutch size did not differ substantially among these populations. All eiders in Hudson Bay laid larger clutches than other subspecies in eastern North America. As Hudson Bay common eiders do not undergo extensive migrations, they may have more energy reserves available to them for egg production. Eiders nesting in eastern Hudson Bay laid larger eggs than eiders nesting in western Hudson Bay. Further, eiders in eastern Hudson Bay tended to be structurally larger, but had smaller bill processes. These differences may have a genetic basis. Smaller egg size and body size may arise in western Hudson Bay from mixing with the smaller borealis subspecies nesting to the north. Further work to resolve genetic affinities, determine levels of male and female dispersal, and examine variation in reproductive ecology are needed to resolve the sources of these differences.
Keywords: Breeding Season; Common Eider; Somateria mollissima; Productivity

Long-tailed duck: Clangula hyemalis - Robertson, Gregory J.; Savard, Jean-Pierre L. (Birds of North America, 2002)
Keywords: Breeding Season; Nonbreeding Seasons; Clangula hyemalis; Long-tailed Duck

Frequency, timing and costs of intraspecific nest parasitism in the common eider - Robertson, Gregory J.; Watson, Michelle D.; Cooke, Fred (Condor, 1992)
Intraspecific nest parasitism was studied in the Hudson Bay race of the Common Eider (Somateria mollissima sedentaria), near Churchill, Manitoba (58 degree 24'N, 94 degree 24'W). Nest parasitism was detected by three methods: (1) multiple eggs laid in the same nest on a single day, (2) eggs laid before or after the host's clutch was laid, and (3) large within-clutch variances in egg size and color. It was determined that 42.4% (n = 153) of completed clutches were parasitized. Parasitic eggs were laid significantly earlier in the host's laying sequence than expected by chance: 65% of parasitic eggs were laid on the first two days of laying. Number of parasitic eggs laid, as a proportion of all eggs, did not change significantly throughout the laying period. The probability of parasitic and host eggs hatching was not significantly different from that in unparasitized nests. Hosts did not reduce their clutch size in response to parasitism, when data were controlled for initiation date, nor did they hatch any fewer of their own young for a given clutch size than unparasitized nests. Parasitized nests were found in areas with higher densities (number of neighbors within 10 m) at initiation. Parasitism in this species does not appear to be a salvage strategy and may be part of a mixed or conditional strategy.
Keywords: Behavior; Breeding Season; Common Eider; Somateria mollissima

Common Eider Wintering Trends in Nova Scotia, 1970-2019 - Robertson, G. J.; Wong, S. N. P.; Tomlik, M. D.; Milton, G. R.; Parsons, G. J.; Mallory, M. L. (JOURNAL OF FISH AND WILDLIFE MANAGEMENT, 2021)
Common eiders Somateria mollissima have been a focus of conservation and management efforts in eastern North American for over a century; however, the complex population structure and multiple subspecies make assessing the status of populations challenging. The coastlines of Nova Scotia, Canada, are an important wintering area for common eiders, and significant harvests of common eiders occur in the province. We analyzed trends in the number of wintering common eiders using the coasts of Nova Scotia from dedicated waterfowl surveys flown since 1970, and every year since 1992. We used Generalized Additive Models to assess the apparent non-linear trends in the counts of common eiders over the past 50 y. We found that numbers of common eiders wintering in Nova Scotia increased from 1970 to the early 2010s, with strong growth in the 2000s (peaking at 7% growth/y). Since the early 2010s, the growth has stopped, and the numbers are now declining. Recent declines in the population wintering in Nova Scotia corroborate other evidence that common eiders are declining in the region, and may also indicate distributional shifts of common eiders in eastern North America.
Times Cited in Web of Science Core Collection: 0 Total Times Cited: 0 Cited Reference Count: 34
Keywords: common eider; Somateria mollissima; SURVIVAL; SOMATERIA-MOLLISSIMA-BOREALIS; GREENLAND; winter surveys; population trend

Long-tailed Duck (Clangula hyemalis) - Robertson, Gregory J. and Jean-Pierre L. Savard (The Birds of North America, 2002)
Keywords: Clangula hyemalis; Long-tailed Duck

Harlequin Duck (Histrionicus histrionicus) - Robertson, Gregory J. and R. Ian Goudie (The Birds of North America, 1999)
Keywords: Histrionicus histrionicus; Harlequin Duck

Diversity and Keratin Degrading Ability of Fungi Isolated from Canadian Arctic Marine Bird Feathers - Robicheau, B. M.; Adams, S. J.; Provencher, J. F.; Robertson, G. J.; Mallory, M. L.; Walker, A. K. (ARCTIC, 2019)
We present the first records of fungi associated with feathers from seabirds and sea ducks in the Canadian Arctic and sub-Arctic. Birds sampled in Nunavut and Newfoundland (Canada) included the Common Eider (Somateria mollissima), King Eider (S. spectabilis), Black-legged Kittiwake (Rissa tridactyla), Northern Fulmar (Fulmarus glacialis), Glaucous Gull (Larus hyperboreus), Black Guillemot (Cepphus grylle), and Thick-billed Murre (Uria lomvia). In total 19 fungal species were cultured from feathers, identified using ITS rDNA barcoding, and screened for their ability to degrade keratin using a keratin azure assay. Our results indicate that 1) of the 19 isolates, 74% were ascomycetes, while the remaining 26% were basidiomycetes (yeasts); 2) 21% of the ascomycete isolates demonstrated keratinolytic activity (a known pathogenicity factor for fungi that may potentially be harmful to birds); 3) the largest number of fungi were cultured from the sampled Thick-billed Murre; and 4) based on a multiple correspondence analysis, there is some indication that both the King Eider and the Thick-billed Murre collected in the low Arctic had distinct fungal communities that were different from each other and from the other birds sampled. Although our sample sizes were small, initial trends in point (4) do demonstrate that additional study is merited to assess whether the fungal community differences are influenced by variation in the known ecologies of the avian hosts and fungi identified.
Times Cited in Web of Science Core Collection: 0 Total Times Cited: 0 Cited Reference Count: 93
Keywords: COMMUNITIES; CLIMATE-CHANGE; Arctic; seabird; POPULATIONS; Nunavut; ANTARCTICA; GENUS; GIBBERELLA; gull; ICE ISLAND; keratin degradation; Newfoundland; PHYLOGENY; SP NOV.; YEASTS

The nesting of Steller's Eider in Norway - Robinson, H. W. (Ibis, 1926)
Comment on a recent record of Polysticta stelleri (Pallas) by George Bolam. || ABSTRACT AUTHORS: W. W. Bowen
Keywords: Breeding Season; Polysticta stelleri; Steller's eider

Migration and morphometrics of the Red-breasted Merganser Mergus serrator in northern Eurasia and the implications for conservation of this species in Britain and Ireland - Robinson, J. A. (Wildfowl, 1999)
Criterion 3c of the Ramsar Convention on wetlands of international importance suggests that a wetland should be considered internationally important if it regularly supports 1% of the individuals in a population of a species or subspecies of waterfowl. A review of the status of Red-breasted Merganser Mergus serrator populations in Europe was conducted to investigate how the 1% threshold for this species should be determined for the UK. Four discrete breeding populations of the nominate race of the Red-breasted Merganser have been identified in northern Eurasia. Ringing recoveries indicate that some birds from the Iceland, east Greenland, Britain and Ireland group are dispersive within their own countries in the non-breeding season whereas others move to coastal waters around Iceland, Britain and Ireland. There is a small amount of evidence, from ringing recoveries and systematic counts, of interchange between birds from this group and those from the rest of north-west Europe. For the designation/identification of 1% thresholds in the UK, the evidence available at present suggests that the north-west and central European population should not be considered separate from those birds which breed in Iceland, east Greenland, Britain and Ireland. However, caution should be taken when interpreting these data and further studies are urgently required to clarify this matter.
Keywords: Breeding Season; Nonbreeding Seasons; Dispersal; Mergus serrator; Red-breasted merganser; Population Delineation

Determinants of wintering waterbird changes in a Mediterranean coastal lagoon affected by eutrophication - Robledano, F.; Esteve, M. A.; Martinez-Fernandez, J.; Farinos, P. (Ecological Indicators, 2011)
Times Cited: 1 Robledano, F. Esteve, M. A. Martinez-Fernandez, J. Farinos, P. Martinez, Julia/J-9681-2012 Martinez, Julia/0000-0001-8675-947X 1

Strong seasonal effects of waterbirds on benthic communities in shallow lakes - Rodriguez-Perez, H.; Green, A. J. (Freshwater Science, 2012)
Rodriguez-Perez, Hector Green, Andy J.

Habitat use by Harlequin Ducks breeding in Hebron Fiord, Labrador - Rodway, Michael S. (Canadian Journal of Zoology, 1998)
Understanding of breeding habitat requirements is vital to recovery plans for the endangered eastern North American population of Harlequin Ducks (Histrionicus histrionicus). I compared habitat characteristics and benthic invertebrate fauna between streams in Hebron Fiord, Labrador, used and unused by Harlequin Ducks in 1996. Used streams were narrower, had higher pH and temperature, a larger substrate, steeper shorelines, and greater vegetation cover on islands and shorelines than unused streams. Greater numbers of invertebrates were recovered from kick samples, simuliid larvae and plecopteran nymphs were more frequent, and chironomid larvae and emphemeropteran nymphs were less frequent in used than in unused streams. Results from this study will help focus future survey and conservation efforts.
Keywords: Breeding Season; Harlequin duck; Histrionicus histrionicus; Habitat

Activity patterns, diet, and feeding efficiency of Harlequin Ducks breeding in northern Labrador - Rodway, Michael S. (Canadian Journal of Zoology, 1998)
The lack of data on summer diet and feeding behaviour for the endangered eastern North American population of Harlequin Ducks (Histrionicus histrionicus) prompted a study of activity patterns and feeding ecology in a coastal stream in Hebron Fiord, Labrador. Diurnal activity patterns varied by habitat and changed through the season. Extensive feeding occurred in slow-moving waters, contrary to expectation. Females spent 40% of daylight hours feeding during the prelaying period, more than twice the time spent by males and higher than that reported in other studies. Diurnal feeding patterns showed little variation in the prelaying period and major peaks of activity in the morning and evening during incubation and brood rearing. Larval Simuliidae (Diptera) were absent from a fecal sample taken in July but dominated the prey remains in feces collected in August. Dive times averaged 10-24 s and varied with depth of water. Dive-pause ratios of 1.7-2.2 were lower than previously reported. The results support the hypothesis that populations are food-limited on the breeding grounds, and suggest that there may be greater energy constraints on foraging effort in river specialists than in dabbling or other diving waterfowl.
Keywords: Behavior; Breeding Season; Harlequin duck; Histrionicus histrionicus; Trophic Interactions

Have winter spacing patterns of harlequin ducks been partially shaped by sexual selection? - Rodway, Michael S. (Waterbirds, 2006)
Sexual selection can operate throughout the annual cycle and likely shapes the winter plumage and courtship displays of many northern waterfowl that choose mates during winter. Less conspicuous effects of sexual selection are likely and in this study I asked whether winter distribution patterns and grouping behavior of Harlequin Ducks (Histrionicus histrionicus) are partially shaped by sexual selection. Harlequin Ducks are typically dispersed in small groups and observed grouping behavior supported the hypothesis that unpaired adult and immature birds will show sexually-selected changes in their spacing to facilitate courtship and mate sampling. Unpaired birds occurred in larger groups than paired birds during October-February, and group-relalated differences in the sex ratio and in the proportion of females that were unpaired indicated that unpaired birds were aggregating g specifically for courtship. Behavior similar to lekking was observed at one site. Males gathered at this site at daybreak, unpaired females visited the site each apparently to attract a group of courting males, and these courting groups left the site without feeding. When herring spawn was available in March, unpaired birds were more likely to move to exploit it and gained both direct nutritional benefits as well as indirect benefits related to changes in time budgets and spacing behavior that facilitated courtship and mate sampling. Overall, results suggest that sexually-selected behaviors that affect the process of mate choice and the timing of pairing are important to consider if we are trying to explain winter spacing patterns of waterfowl.
Keywords: Behavior; Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Habitat

Timing of pairing in waterfowl II: Testing the hypotheses with Harlequin Ducks - Rodway, Michael S. (Waterbirds, 2007)
Intra-specific predictions of the male-costs and mutual-choice hypotheses to explain variation in the timing of pairing in waterfowl were tested in a longitudinal study of marked, known-aged Harlequin Ducks (Histrionicus histrionicus). Pairing chronologies and seasonal changes in time-activity budgets and rates of aggressive interactions were compared in relation to sex, age, and paired status. Results supported the mutual-choice and not the male-costs hypothesis. Paired females gained no immediate benefits relative to unpaired females from mate defense and vigilance, and there was no evidence that females preferred to pair as early as possible, as postulated by the male-costs hypothesis. Unpaired males spent much more time in courtship than paired males spent in mate defense and constraints on male time and energy budgets was not a plausible reason for delayed and protracted pairing of young and re-pairing females. As predicted by the mutual-choice hypothesis, decisions by females about how much time and energy to allocate to the pairing process appeared to be the main factor controlling the timing of pairing in Harlequin Ducks. Newly-pairing females invested an extended period of time in courtship and mate sampling before pairing, in spite of an abundance of courting males clearly energetically capable of maintaining a pair bond. Many young females decided to pair during mid-winter when time constraints to males should have been most severe. Time-budget trade-offs were apparent for young females and their date of pairing was related to the amount of time per day that they allocated to courtship. Pairing success of males was not related to their rate of courtship, nor was it related to the length of time they invested in courtship as they began courting while they were still immature and generally courted for several years before pairing.
Keywords: Behavior; Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus

Pair-bond Defense Relates to Mate Quality in Harlequin Ducks (Histrionicus histrionicus) - Rodway, M. S. (Waterbirds, 2013)
Times Cited: 0 Rodway, Michael S. 0
Keywords: Behavior; Breeding Season; Harlequin duck; Histrionicus histrionicus

Effect of food availability on arrival and departure decisions of Harlequin Ducks at diurnal feeding grounds - Rodway, Michael S.; Cooke, Fred (Condor, 2001)
We investigated three types of decisions made by Harlequin Ducks (Histrionicus histrionicus) in moving between nearshore feeding and offshore resting areas: when to move, whether to move synchronously, and whether to form dense flocks on the roosting grounds. We used the spawning of Pacific herring (Clupea pallasi) as a natural food-supplementation experiment. Birds arrived at nearshore feeding areas a few minutes later and departed almost an hour earlier relative to sunrise and sunset when spawn was available than before and after. Cloud cover and high winds resulted in earlier departures, especially during spawning. Arriving, departing, and offshore groups consisted most frequently of two ducks, and birds showed little tendency to synchronize movements or to form dense flocks when resting. Results indicate that Harlequin Ducks avoid crepuscular and nocturnal periods near shore when not constrained by food availability and the length of daylight in which to feed.
Keywords: Behavior; Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Trophic Interactions

Use of fecal analysis to determine seasonal changes in the diet of wintering Harlequin Ducks at a herring spawning site - Rodway, Michael S.; Cooke, Fred (Journal of Field Ornithology, 2002)
Few data are available on seasonal changes in winter diet of Harlequin Ducks (Histrionicus histrionicus), especially in relation to their use of Pacific herring (Clupea pallasi) spawn. We used fecal analyses to determine seasonal changes in Harlequin Duck winter diet at a site where Pacific herring spawn. We measured frequency of occurrence and relative abundance by volume of prey remains in 202 fecal samples collected during four date periods in 1998 and 1999. These two measures were highly correlated. We identified snails, crabs, limpets, and chitons as the principal animal prey, and ranked relative importance of most prey types in similar order as previous studies using stomach analyses. Crabs parts constituted the majority of prey remains during molt, and we concluded that crabs were dominant in the diet during molt because crabs generally have greater organic content and less hard-part remains per unit of body mass than other hard-shelled prey consumed at that time. Snail remains were highest in frequency of occurrence during winter. Herring eggs were not detected in feces until a week after herring spawned, but abrupt changes in other prey types indicated that herring eggs were the principal prey throughout the spawn period. Polychaetes increased in importance in winter and spring, and rated third in frequency of occurrence in spring. We recommend using fecal analyses to determine frequency of occurrence of prey in the diet of other sea-ducks that are known to feed on hard-shelled molluscs and crustaceans. Measures of relative abundance of prey remains can be useful if conversion factors relating hard-part remains to whole-body biomass are available.
Keywords: Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Techniques; Trophic Interactions

Discovery of a Harlequin Duck nest in Eastern North America - Rodway, Michael S.; Goose, John W., Jr.; Fong, Ian; Montevecchi, William A. (Wilson Bulletin, 1998)
Harlequin Ducks (Histrionicus histrionicus) were observed breeding on a tributary of the northwestern arm of Hebron Fiord, Labrador. Peak population numbers were 11 males and 13 females on 17 June; females consistently outnumbered males. Breeding was confirmed by the presence of a nest with eggs and the presence of downy chicks.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Harlequin duck; Histrionicus histrionicus

Aggregative response of Harlequin Ducks to herring spawning in the Strait of Georgia, British Columbia - Rodway, Michael S.; Regehr, Heidi M.; Ashley, John; Clarkson, Peter V.; Goudie, R. Ian; Hay, Douglas E.; Smith, Cyndi M.; Wright, Kenneth G. (Canadian Journal of Zoology, 2003)
We determined the scale of aggregative response of Harlequin Ducks (Histrionicus histrionicus) to seasonally and locally superabundant prey at Pacific herring (Clupea pallasi) spawning sites in the northern Strait of Georgia, British Columbia, in 1995-2002. Aggregations of 3400-5500 birds gathered at a small number of sites along the same 8-km stretch of shoreline each year that spawn was available there. Aggregations occurred in only a small fraction of the habitat area where spawn was available. Duration of stay at spawning sites averaged 2-3 weeks and many birds returned to their wintering grounds afterwards. Birds moving to spawning sites represented 55-87% of the total wintering population. The proportion of local wintering populations that moved to spawning sites was negatively related to the distance they had to travel, and few birds travelled farther than 80 km. The decline in proportions moving with increasing distance suggests that more distant individuals may be constrained by a lack of information or that there are trade-offs between the benefits of exploiting spawn and the costs of movement. This raises a conservation concern because the temporal and geographic range of herring spawning in British Columbia is contracting and some wintering water-bird populations may be losing access to this important late-winter food.
Keywords: Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Dispersal; Trophic Interactions

Sex and age differences in distribution, abundance, and habitat preferences of wintering Harlequin Ducks: Implications for conservation and estimating recruitment rates - Rodway, Michael S.; Regehr, Heidi M.; Cooke, Fred (Canadian Journal of Zoology, 2003)
We determined the sex- and age-specific distribution, abundance, and habitat preferences of wintering Harlequin Ducks (Histrionicus histrionicus) and evaluated potential biases in measuring ratios of immature males to adult males to estimate recruitment rates. A comparison of the occurrence of birds with habitat availability at the 1-km scale indicated a preference for wide intertidal habitat with cobble-gravel or bedrock-boulder substrate, small offshore islets and shoreline with attached or nearby reefs and islets, areas without streams, and areas with a greater historical abundance of herring spawn. Where the substrate was bedrock-boulder, birds preferred areas with tidal rapids. Densities of birds were highest along linear and complex shorelines with reefs or islets where intertidal habitat was >100 m wide and substrate was cobble-gravel or bedrock-boulder. Patterns of habitat use among sex and age classes were the same at the 1-km scale but differed at smaller scales, with adult and immature males occurring farther offshore than females. Age ratios varied among areas and were biased by survey method and misidentification of distant birds. Correcting for detected biases gave an estimated male age ratio of 9.8%. Calculated estimates of female recruitment suggest a declining population, but it is necessary to incorporate emigration in estimates of adult survival before demographic trends can be confidently inferred.
Keywords: Abundance, Distribution, and Trends; Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus; Productivity; Techniques; Habitat

Molting Migration in Southern Jutland and at Kalmarsund - Roed, U. (Flora og Fauna, 1971)
Keywords: Common Eider; Nonbreeding Seasons; Molt; Migration; Somateria mollissima; Black Scoter; Melanitta nigra

Predicting bird oiling events at oil sands tailings ponds and assessing the importance of alternate waterbodies for waterfowl: A preliminary assessment - Ronconi, Robert A. (Canadian Field-Naturalist, 2006)
Tailings ponds are an integral part of oil sands mining development in northeastern Alberta, but waterfowl and shorebirds often land in these ponds during spring migration where they may become covered with oil. For decades, managers have developed and implemented methods for deterring birds from landing in these ponds, yet no deterrent strategy is fully effective. Therefore, to enhance deterrence strategies, it will be important to understand the environmental conditions that influence bird use of tailings ponds. This study quantified waterfowl flights over, and use of, tailings ponds and compared this use to waterfowl activity at natural waterbodies in the region over a single spring migration period. Results suggest that waterfowl are most likely to land on tailings ponds before lakes have thawed, after which migratory ducks appeared mainly to use natural waterbodies for migratory stopover sites. Very high numbers of waterfowl were observed on one waterbody, Kearl Lake, suggesting that this lake may be of greater importance to spring staging waterfowl than previously thought. A small sample of birds oiled at tailings ponds were examined in relation to spring weather conditions. Logistic regression analysis demonstrated that the probability of birds being oiled tended to increase with precipitation levels. Results of this study suggest that (1) preservation of natural waterbodies may play an important role in minimizing bird use of tailings ponds, and (2) future bird deterrence efforts should especially aim to deter birds during rainy weather conditions when birds may be more likely to become oiled. These results were from a small sample size, are preliminary in nature, and should be interpreted with caution. A concerted and careful effort to collect and thoroughly analyze long-term records of oiled birds may reveal important environmental effects predicting bird oiling events.
Keywords: Sea Ducks - General; Contaminants

Estimates of changes in seabird numbers in the Grand Manan Archipelago, New Brunswick, Canada - Ronconi, Robert A.; Wong, Sarah N. P. (Waterbirds, 2003)
A census of the Grand Manan Archipelago, New Brunswick, Canada, found nine seabird species nesting at 22 sites. Herring Gull (Larus argentatus) and Common Eider (Somateria mollissima) were the most widely distributed species, with a combined 89% of all breeding seabirds in the region. Although fewer, the Great Black-backed Gull (Larus marinus) and Black Guillemot (Cepphus grylle) were widely distributed. Other seabirds had more limited distributions; one Common Tern (Sterna hirundo) colony, three Double-crested Cormorant (Phalacrocorax auritus) colonies and one mixed colony of Razorbill (Alca torda) and Common Murre (Uria aalge). Leach's Storm-Petrel (Oceanodroma leucorhoa) numbers were not determined, but were found nesting on three islands and were suspected to be nesting on two others. Comparisons with historical data showed increases in gulls, Razorbill and Common Murre, whereas eiders had remained relatively stable over the past two decades, but had decreased in recent years. Insufficient data are available to assess trends of other seabird species nesting around Grand Manan. Fluctuations in cormorant numbers may be a result of moving breeding sites. The recent decrease in eider numbers may be a consequence of low survival rates of young and increasing numbers of predatory gulls. Considerable discrepancies were observed between recent and historical gull numbers which may have resulted from 1) differences in survey methodology, and 2) survey timing. This study provides estimates of breeding seabirds, which can be used as baseline data for future monitoring in the Grand Manan Archipelago.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Common Eider; Sea Ducks - General

Breeding success and breeding population trends of waterfowl: implications for monitoring - Ronka, M.; Saari, L.; Hario, M.; Hanninen, J.; Lehikoinen, E. (Wildlife Biology, 2011)
Times Cited: 2 Ronka, Mia Saari, Lennart Hario, Martti Hanninen, Jari Lehikoinen, Esa Lehikoinen, Esa /I-6128-2013 Lehikoinen, Esa /0000-0002-6932-3604 2
Keywords: Breeding Season; Abundance, Distribution, and Trends; Techniques; Common eider; somateria mollissima; productivity

Environmental changes and population trends of breeding waterfowl in northern Baltic Sea - Ronka, Mia T. H.; Saari, C. Lennart V.; Lehikoinen, Esa A.; Suomela, Janne; Hakkila, Kauko (Annales Zoologici Fennici, 2005)
Causes behind the changes in waterfowl populations in the Archipelago Sea, SW Finland, have until now not been quantitatively analysed. We modelled the impact of eutrophication, winter severity, weather conditions during breeding and water salinity on the breeding populations of ten waterfowl species (ducks, great crested grebe Podiceps cristatus and coot Fulica atra) using generalised linear models and the program TRIM (TRends and Indices in Monitoring data). The populations of the goldeneye Bucephala clangula, coot and velvet scoter Melanitta fusca decreased with increasing eutrophication. The populations of the goldeneye, coot, mallard Anas platyrhynchos, mute swan Cygnus olor and eider Somateria mollissima were most vulnerable to winter severity. We did not find evidence for impacts of weather conditions during breeding or water salinity on population trends. We also discuss alternative explanations to the observed population trends, such as predation and disturbance.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Sea Ducks - General

Environmental changes and population trends in breeding waterfowl in the northern Baltic Sea - Ronka, M. T. H.; Saari, L.; Lehikoinen, E. A.; Suomela, J. (Journal of Ornithology, 2006)
Keywords: Breeding Season; Abundance, Distribution, and Trends; Sea Ducks - General

Neither season nor sex affects the cost of terrestrial locomotion in a circumpolar diving duck: the common eider (Somateria mollissima) - Rose, K. A.; Tickle, P. G.; Lees, J. J.; Stokkan, K. A.; Codd, J. R. (Polar Biology, 2014)
Locomotion accounts for a significant proportion of the energy budget in birds, and selection is likely to act on its economy, particularly where energy conservation is essential for survival. Birds are capable of different forms of locomotion, such as walking/running, swimming, diving and flying, and adaptations for these affect the energetic cost [cost of locomotion (CoL)] and kinematics of terrestrial locomotion. Furthermore, seasonal changes in climate and photoperiod elicit physiological and behavioural adaptations for survival and reproduction, which also influence energy budget. However, little is understood about how this might affect the CoL. Birds are also known to exhibit sex differences in size, behaviour and physiology; however, sex differences in terrestrial locomotion have only been studied in two cursorially adapted galliform species in which males achieved higher maximum speeds, and in one case had a lower mass-specific CoL than females. Here, using respirometry and high-speed video recordings, we sought to determine whether season and sex would affect the CoL and kinematics of a principally aquatic diving bird: the circumpolar common eider (Somateria mollissima). We demonstrate that eiders are only capable of a walking gait and exhibit no seasonal or sex differences in mass-specific CoL or maximum speed. Despite sharing identical limb morphometrics, the birds exhibited subtle sex differences in kinematic parameters linked to the greater body mass of the males. We suggest that their principally aquatic lifestyle accounts for the observed patterns in their locomotor performance. Furthermore, sex differences in the CoL may only be found in birds in which terrestrial locomotion directly influences male reproductive success.
Rose, Kayleigh A. Tickle, Peter G. Lees, John J. Stokkan, Karl-Arne Codd, Jonathan R.
Keywords: Behavior; Common Eider; Somateria mollissima; Energetics and Nutrition

Seasonal Movements and Distribution of Steller's Eiders (Polysticta stelleri) Wintering at Kodiak Island, Alaska - Rosenberg, D. H.; Petrula, M. J.; Schamber, J. L.; Zwiefelhofer, D.; Hollmen, T. E.; Hill, D. D. (Arctic, 2014)
We used satellite telemetry in 2004-06 to describe the annual movements and habitat use of a segment of the Pacific population of Steller's Eiders (Polysticta stelleri) that winters at Kodiak Island, Alaska. Information about broad-scale patterns of seasonal distribution and links among annual cycle stages is critical for interpreting population trends and developing conservation strategies. We captured birds in Chiniak Bay at Kodiak Island in late February and early March and monitored the movements after departure from Kodiak Island of 24 satellite-tagged birds: 16 after-second-year (ASY) age class females, one second-year age class female, and seven ASY males. All birds used the same intercontinental migration corridor during spring, but routes and chronology of spring migration appeared to vary by year and among individuals. Sixteen of the 24 birds that were tracked migrated to breeding areas along the Arctic coast of Russia from the Chukotka Peninsula to the Taymyr Peninsula; five birds, assumed to be non-breeding, spent the summer in nearshore waters of Russia and Alaska; and the remaining three birds either died during spring migration or had failed transmitters. Thirteen birds were tracked to molt sites that were broadly distributed along the coast of Alaska. Molt sites included St. Lawrence Island, the Kuskokwim Shoals, Kamishak Bay, and three sites along the Alaska Peninsula. Twelve of these 13 birds returned to Kodiak Island to winter, and a single male wintered on the Alaska Peninsula. Steller's Eiders marked during winter at Kodiak Island were widely distributed during the breeding season,. but a large proportion of marked birds returned to molting and wintering areas in two years of the study.
Rosenberg, Daniel H. Petrula, Michael J. Schamber, Jason L. Zwiefelhofer, Denny Hollmen, Tuula E. Hill, Douglas D.
Keywords: Molt; Migration; Habitat; Nonbreeding season; Polysticta stelleri; Steller’s Eider

Use of underwater playback to reduce the impact of eiders on mussel farms - Ross, B. P.; Lien, J.; Furness, R. W. (ICES Journal of Marine Science, 2001)
One of the most commonly employed methods of reducing damage by diving ducks to mussel stocks on mussel farms in Atlantic Canada and in Scotland is chasing birds by boat. While effective in the short term, the frequency of chases is often restricted by high costs, both in time and fuel. Tests in Scotland used underwater recordings of chase-boat engines replayed at regular intervals on continuous loop tapes through an underwater loudspeaker in an attempt to reduce predation pressure by eiders on mussel farms. Trials of the underwater playback system (UPS) gave significant reductions in eider numbers of 50-80%, while a control trial with the playback of an unassociated noise gave no reduction in numbers. The mean return time of birds to the farm after chasing by boat also increased significantly. As the presence of workers on mussel farms reduces the number of eiders feeding there, the UPS is a useful deterrent when workers are not present. The long-term habituation of ducks to the system was negligible when workers are absent, providing there is occasionally reinforcement of the deterrent by boat chasing. Potential factors effecting the efficacy of the UPS are discussed.
Keywords: Conservation; Common Eider; Nonbreeding Seasons; Somateria mollissima; Techniques

An Estimate of the Black Scoter Melanitta-Nigra Population Molting in James and Hudson Bays Canada - Ross, R. K. (Canadian Field-Naturalist, 1983)
On July 26 and 27, 1977, an aerial survey was made of the flocks of molting black scoter (M. nigra) off the northern Shore of Ontario. On that flight, 88,700 molting male black scoters were counted by means of aerial photography; such a total could represent up to 320,300 birds in eastern North America in the early fall. Only 7% of that number were located during wintering ground surveys in the eastern USA. On regaining their powers of flight, most of the black scoter apparently moved from the Ontario shore to southeastern James Bay where they staged during Aug. and Sept. prior to the fall migration.
Keywords: Abundance, Distribution, and Trends; Nonbreeding Seasons; Molt; Black Scoter; Melanitta nigra

Abundance and distribution of breeding waterfowl in the Great Clay Belt of northern Ontario - Ross, R. Kenyon; Abraham, Kenneth F.; Gadawski, Ted R.; Rempel, Robert S.; Gabor, T. Shane; Maher, Ron (Canadian Field-Naturalist, 2002)
The abundance and distribution of breeding waterfowl in the Great Clay Belt of northern Ontario was determined through helicopter surveys of 117 fixed plots (2X2 km each) during the nest initiation periods from 1988 to 1990. This area has higher fertility, flat topography, high water table and better access than the surrounding Boreal Forest, and therefore has greater potential for increased waterfowl production through habitat management. Overall breeding density averaged 112.5 indicated breeding pairs per 100 km2, 68% being of the four most common species (Mallard (Anas platyrhynchos), Ring-necked Duck (Aythya collaris), American Black Duck (Anas rubripes), and Common Goldeneye (Bucephala clangula)); 13 other species were encountered. The average total of breeding waterfowl for the region was estimated at 59330 pairs. Distributions of the species were related to ecodistrict and to surficial geology. The more northerly of the two main ecodistricts had higher densities of American Black Ducks, Ring-necked Ducks, Common Goldeneyes, and Canada Geese (Branta canadensis). Mallard and Hooded Merganser (Lophodytes cucullatus) distributions correlated with presence of surficial clay and moraines, respectively. Less common species including Green-winged Teal (Anas crecca) and American Wigeon (Anas americana) appeared to be concentrated in smaller-scaled habitat features (beaver pond sequences and estuarine marshes, respectively). Results generally agreed with those of earlier Clay Belt surveys. Total breeding density of waterfowl is slightly higher than that of surrounding regions.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Sea Ducks - General

Autumn diet of greater scaup, lesser scaup, and long-tailed ducks on eastern Lake Ontario prior to zebra mussel invasion - Ross, R. Kenyon; Petrie, Scott A.; Badzinski, Shannon S.; Mullie, Adele (Wildlife Society Bulletin, 2005)
Diving ducks staging on the lower Great Lakes have responded to the introduction and subsequent population increase of zebra mussels (Dreissena polymorpha) by consuming this readily available food. However, nutritional and contaminant-related implications of recent dietary shifts are hindered by the fact that few studies have documented foods consumed by diving ducks before zebra mussels invaded the Great Lakes in 1988. We examined diets of greater scaup (Aythya marila), lesser scaup (Aythya affinis), and long-tailed ducks (Clangula hyemalis) collected from eastern Lake Ontario during autumn 1986 and 1987 to determine differences among the 3 species. Gastropods were the main food item of greater (92% aggregate dry mass) and lesser scaup (86%), but they consumed relatively small amounts (3% and 7%, respectively) of amphipods. In contrast, amphipods made up 66% of the diets of long-tailed ducks; gastropods were 28% of their diet. Amphipod populations have increased and native gastropods decreased in the presence of zebra mussels in the lower Great Lakes, such that zebra mussel invasion likely has had greater dietary implications for scaup than for long-tailed ducks. Dietary shifts from nonfilter-feeding gastropods to filter-feeding zebra mussels likely contributed to elevated contaminant burdens in lesser and greater scaup on the lower Great Lakes. We encourage further research into the diet-, nutrient-, and contaminant-related implications of zebra mussel induced ecological changes to the Great Lakes.
Keywords: Nonbreeding Seasons; Clangula hyemalis; Long-tailed Duck; Trophic Interactions

Harvest of sea ducks in North America: A contemporary summary - Rothe, T. C., P. I. Padding, L. C. Naves, and G. J. Robertson (Studies in Avian Biology, 2015)
Sea ducks present unique challenges to waterfowl harvest management because the species have relatively low intrinsic population growth rates and varied population structure and harvest occurs under a diversity of rangewide hunting traditions. Sea duck harvest occurs throughout North America, ranging from inland harvest of widely distributed species, such as goldeneyes and mergansers, to specialized harvest of eiders and scoters in coastal and northern regions. Harvest of widely distributed species is well represented in continental waterfowl harvest monitoring programs. More localized harvests, such as those in coastal and remote areas, have proven challenging to monitor, and some special surveys have been implemented. Sea duck harvest regulations have evolved over the decades according to changes in population levels, management philosophies, and improvements in harvest information. Hunting of goldeneyes and Buffleheads has usually been regulated within general bag limits for ducks. Regulations for large mergansers have been liberal, but limits for Hooded Mergansers have remained conservative. Harvest regulations for eiders, scoters, Long-tailed Ducks, and Harlequin Ducks have recently become more restrictive, subject to special seasons and bag limits in primary coastal hunting areas. With a few exceptions, harvest of widely distributed species and most species along the Pacific Coast is considered sustainable. Common Eider harvest in the Atlantic Flyway is a management concern given fluctuations in eider populations, high harvest pressure, and the presence of two subspecies. Sea ducks are important subsistence resources in the North; eiders are harvested by coastal communities and scoters by inland communities. Harvest estimates are now available for most northern jurisdictions, and management is undertaken in cooperation with First Nations and Inuit organizations in Canada and subsistence management bodies in Alaska. Additional information on the delineation and demography of sea duck populations is essential, along with improved harvest estimation techniques, to inform collaborative harvest management and to ensure sustainable harvest.
Keywords: Conservation

Mercury concentrations in muscle, brain and bone of Western Alaskan waterfowl - Rothschild, Roger F. N.; Duffy, Lawrence K. (Science of the Total Environment, 2005)
Total mercury (THg), which includes both inorganic (Hg2+) and methylmercury (MeHg) species, has been reported for seabirds in the North Pacific and Alaska. For the Yup'ik and Aleut people of Alaska, waterfowl are a small but important seasonal component of the diet, but many Alaskan species have not been studied extensively for the presence of mercury. Birds are good subjects for examination of mercury concentrations because they feed at different trophic levels, they can be long-lived, and many are both abundant and widely distributed. In this study, we present the levels of mercury in muscle, brain, and bone tissue of 140 birds taken by subsistence food users across Western Alaska. THg wet weight mean concentrations in the 18 species of waterfowl surveyed ranged from 0.8 to 268.6 ng/g in muscle, from 0.4 to 197.7 ng/g in brain and from 0.7 to 422.9 ng/g in bone. The null hypothesis that there are no interspecific differences in the level of total mercury in the 18 species of Alaska birds surveyed was not supported. We found interspecific differences with the Lesser Scaup (Aythya affinis), and the Black Scoter (Melanitta nigra), having the highest muscle tissue levels of THg. In general, THg mean levels were higher in muscle than in brain with the exceptions of the Bar-tailed Godwit and Northern Shoveler. Bone THg were highest in the Black Scoter. The mean values for THg in the species studied are unlikely to cause adverse reproductive or behavioral effects in the birds. (c) 2005 Published by Elsevier B.V.
Keywords: Contaminants; Black Scoter; Melanitta nigra

Buoys with looming eyes deter seaducks and could potentially reduce seabird bycatch in gillnets - Rouxel, Y.; Crawford, R.; Cleasby, I. R.; Kibel, P.; Owen, E.; Volke, V.; Schnell, A. K.; Oppel, S. (ROYAL SOCIETY OPEN SCIENCE, 2021)
Bycatch of seabirds in gillnet fisheries is a global conservation issue with an estimated 400 000 seabirds killed each year. To date, no underwater deterrents trialled have consistently reduced seabird bycatch across operational fisheries. Using a combination of insights from land-based strategies, seabirds' diving behaviours and their cognitive abilities, we developed a floating device exploring the effect of large eyespots and looming movement to prevent vulnerable seabirds from diving into gillnets. Here, we tested whether this novel above-water device called 'Looming eyes buoy' (LEB) would consistently deter vulnerable seaducks from a focal area. We counted the number of birds present in areas with and without LEBs in a controlled experimental setting. We show that long-tailed duck Clangula hyemalis abundance declined by approximately 20-30% within a 50 m radius of the LEB and that the presence of LEBs was the most important variable explaining this decline. We found no evidence for a memory effect on long-tailed ducks but found some habituation to the LEB within the time frame of the project (62 days). While further research is needed, our preliminary trials indicate that above-water visual devices could potentially contribute to reduce seabird bycatch if appropriately deployed in coordination with other management measures.
Times Cited in Web of Science Core Collection: 9 Total Times Cited: 9 Cited Reference Count: 62
Keywords: BEHAVIOR; RESPONSES; LONGLINE; seabirds; MORTALITY; MITIGATION; FISHERIES; bycatch; COLLISION; deterrent; gillnet; marine conservation; mitigation measures; NUCLEUS ROTUNDUS; RANDOM FORESTS; VARIABLE IMPORTANCE MEASURE

Dioxin type and mixed type induction of the cytochrome P-450 system of common eider ducklings (Somateria mollissima) by PCBs: With indications for biotransformation - Rozemeijer, M. J. C.; Boon, J. P.; Swennen, C.; Brouwer, A.; Murk, A. J. (Aquatic Toxicology (Amsterdam), 1995)
In order to investigate the effects of PCBs on biotransformation enzymes and metabolism, 4-week-old common eider ducklings were exposed to single ip doses of 3,3',4,4' tetrachlorobiphenyl (CB 77) (5 or 50 mg/kg) or the technical mixture Clophen A50 (Clo A50) (50 or 200 mg/kg). The control group was injected with corn oil only (5 ml/kg). Comparison of CB patterns in adipose tissue of the Clo A50 injected groups with the original Clo A50 mixture revealed specific reduction of congeners with vicinal H atoms in the meta and para positions, suggesting biotransformation by the monooxygenase system (MO) as the most probable cause. For the group injected with 200 mg Clo A50, a difference in congener pattern was shown between liver and adipose tissue. This indicates either a saturation of the hepatic biotransformation capacity, or slow redistribution of the congeners from the adipose tissue to the site of metabolism (liver). Using only one adipose tissue concentration point in time, indicative biological half-lives for metabolizable congeners were calculated from congener pattern changes, ranging from 3.6 days for CB 44 to 16.1 days for CB 101. CB 77 caused a dose-dependent induction of total cytochrome P450, whole liver cytochrome P450, EROD and PROD activity. On the contrary, Clo A50 had no inducing effects after this specific incubation period. PROD activity measurements suggest that the PROD assay may not be not a suitable indicator for CYP2B induction in common eider ducklings. Sex difference and parasitic infection had no influence on the biochemical responses measured. Internal dose-induction response curves were established; a very tentative maximum no effect level on toxic equivalents (TEQ) basis is suggested (7 ng TEQ/g lipid). Under these incubation conditions, exposure to CB 77 and Clophen A50 did not influence the infection rates of the intestinal parasite Polymorphus botulus (Acanthocephala).
Keywords: Breeding Season; Common Eider; Contaminants; Somateria mollissima

Non-resident definitive host presence is sufficient to sustain avian schistosome populations - Rudko, S. P.; McPhail, B. A.; Reimink, R. L.; Froelich, K.; Turnbull, A.; Hanington, P. C. (INTERNATIONAL JOURNAL FOR PARASITOLOGY, 2022)
To control swimmer's itch in northern Michigan inland lakes, USA, one species of bird, the common merganser (Mergus merganser), has been relocated from several lakes since 2015. Relocation efforts are driven by a desire to reduce the prevalence of the swimmer's itch-causing parasite Trichobilharzia stagnicolae. The intention of this state-sponsored control effort was to interrupt the life cycle of T. stagnicolae and reduce parasite egg contribution into the environment from summer resident mergansers such that infections of the intermediate snail host Stagnicola emarginata declined. Reduced snail infection prevalence was expected to substantially reduce the abundance of the swimmer's itch-causing cercarial stage of the parasite in water. With no official programme in place to assess the success of this relocation effort, we sought to study the effectiveness and impact of the removal of a single definitive host from a location with high definitive host and parasite diversity. This was assessed through a comprehensive, lake-wide monitoring study measuring longitudinal changes in the abundance of three species of avian schistosome cercariae in four inland Michigan lakes. Environmental measurements were also taken at these lakes to understand how they can affect swimmer's itch incidence. This study demonstrates that the diversity of avian schistosomes at the study lakes would likely make targeting a single species of swimmer's itchcausing parasite meaningless from a swimmer's itch control perspective. Our data also suggest that removing the common merganser is not an effective control strategy for the T. stagnicolae parasite, likely due to contributions of the parasite made by non-resident birds, possibly migrants, in the autumn and spring. It appears likely that only minimal contact time between the definitive host and the lake ecosystem is required to contribute sufficient parasite numbers to maintain a thriving population of parasite species with high host specificity. (C) 2022 The Author(s). Published by Elsevier Ltd on behalf of Australian Society for Parasitology.
Times Cited in Web of Science Core Collection: 6 Total Times Cited: 6 Cited Reference Count: 38
Keywords: Common merganser; TEMPERATURE; COMMUNITY; Trichobilharzia; CERCARIAE; Cercarial dermatitis; DERMATITIS; LYME-DISEASE; PARASITE DIVERSITY; PERSISTENCE; PRAZIQUANTEL; Relocation; Schistosome; Swimmer's itch; SWIMMERS ITCH; TREMATODES

Methylmercury and total mercury content in soft tissues of two bird species wintering in the Baltic Sea near Gdansk, Poland - Rutkowska, M.; Bajger-Nowak, G.; Kowalewsk, D.; Bzoma, S.; Kalisinska, E.; Namiesnik, J.; Konieczka, P. (CHEMOSPHERE, 2019)
Of the various forms of Hg occurring in nature, (mono) methylmercury (MeHg) is an especially toxic form and practically all forms of Hg can be converted into MeHg as a result of natural processes. Total mercury (THg) and MeHg were determined in tissues of two piscivorous birds: razorbill Alca torda and black-throated loon Gavia arctica to provide baseline data on current mercury concentrations for liver, kidneys and pectoral muscle mercury concentrations of birds which winter on the south Baltic Sea coast. Intra and inter-specific comparisons were carried out. The study is conducted between winter and autumn and the distributions of mercury in tissues were compared with data in other studies. The following paper contains discussion of the results based on the statistical analysis and ecology aspect. The highest average Hg content was in the liver (loon approximate to 3.86 mg kg(-1) dw; razorbill approximate to 1.57 mg kg(-1) dw), then in the kidneys (loon approximate to 3.14 mg kg(-1) dw; razorbill approximate to 1.53 mg kg(-1) dw) and the lowest concentrations were in pectoral muscles (loon approximate to 1.97 mg kg(-1) dw; razorbill approximate to 0.67 mg kg(-1) dw). (C) 2018 Elsevier Ltd. All rights reserved.
Times Cited in Web of Science Core Collection: 7 Total Times Cited: 7 Cited Reference Count: 71
Keywords: Birds; Liver; ACCUMULATION; Mercury; SELENIUM; ALCA-TORDA; AQUATIC ECOSYSTEM; ELEMENT CONCENTRATIONS; FRESH-WATER FISH; GAS-CHROMATOGRAPHY; Kidney; MERGANSERS MERGUS-MERGANSER; Methylmercury; Pectoral muscle; PUCK BAY; TRACE-METALS

Maternal investment, female philopatry and reproductive success in the common goldeneye Bucephala clangula - Ruusila, Vesa (Annales Universitatis Turkuensis Series A II Biologica-Geographica-Geologica, 1999)
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye; Productivity; Dispersal

Characteristics of maternal family lineages in a Common Goldeneye Bucephala clangula breeding population - Ruusila, Vesa; Poysa, Hannu; Runko, Pentti (Ornis Fennica, 2000)
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye

Female wing plumage reflects reproductive success in Common Goldeneye Bucephala clangula - Ruusila, Vesa; Poysa, Hannu; Runko, Pentti (Journal of Avian Biology, 2001)
Recent studies on the function of female plumage characteristics have yielded ambiguous results. Some studies have found an association between different physiological, ecological or behavioural traits and female plumage, while others have found no association and interpret female plumage as neutral in function. We observed a high variance among females in both wing plumage and breeding success in female Common Goldeneyes Bucephala clangula, a sexually plumage-dimorphic diving duck. We studied the association between female wing plumage and hatching date. Principal component analysis of four wing patch area measurements derived a single factor describing wing plumage. Wing plumage was strongly associated with hatching date, which is the most important determinant of goldeneye recruit production; irrespective of age, females with more white in the wing bred earlier than individuals with more black in the wing. We propose that the wing pattern in Common Goldeneye females reflects individual quality.
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Productivity

Costs and benefits of female-biased natal philopatry in the common goldeneye - Ruusila, Vesa; Poysa, Hannu; Runko, Pentti (Behavioral Ecology, 2001)
Sex-biased natal dispersal in long-lived species may result in interactions between parents and mature young of the philopatric sex. To investigate the evolutionary basis of natal philopatry in a noncooperative species, the common goldeneye Bucephala clangula, we studied possible costs and benefits of simultaneous breeding of females and philopatric daughters. We did not find any fitness consequences of a daughter's breeding on their mother's breeding in terms of nest-site selection, body weight, clutch size, hatching date, or hatching success. Our results, therefore, did not support the assumption of the local resource competition hypothesis, that the natally philopatric sex should be more costly to a breeding parent. As possible benefits for daughters returning to their natal area, we tested inheritance of nest sites from mothers and explored whether daughters utilize the presence of their mother by parasitically sneaking into her mother's nest. Daughters' nest-site selection was not associated with the presence of their mothers. A comparison between daughters and control females revealed that daughters chose their nest site closer to their natal nest than expected by nest-site availability alone. Daughters could not expect to inherit a nest site from their mother, and we did not find other indications of cooperation between relatives either. The mother's clutch size did not increase in the year breeding with the daughter, indicating daughters do not parasitize their mother's nest. We suggest that benefits such as decreased nest predation risk associated with nesting close to the natal nest site may be important in the natal philopatric behavior of the species.
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye; Dispersal

Are attentive mothers preferentially parasitised? - Ruxton, Graeme D. (Behavioral Ecology and Sociobiology, 1999)
Keywords: Behavior; Breeding Season; Common Eider; Somateria mollissima

Using time series to estimate rates of population change from abundance data - Ryding, Kristen E.; Millspaugh, Joshua J.; Skalski, John R. (Journal of Wildlife Management, 2007)
Assessing the dynamics of wild populations often involves an estimate of the finite rate of population increase (lambda) or the instantaneous rate of increase (r). However, a pervasive problem in trend estimation is that many analytical techniques assume independent errors among the observations. To be valid, variance estimates around lambda (or r) must account for serial correlation that exists in abundance data. Time series analysis provides a method for estimating population trends and associated variances when serial correlation of errors occurs. We offer an approach and present an example for estimating lambda and its associated variance when observations are correlated over time. We present a simplified time series method and variance estimator to account for autocorrelation based on a moving average process. We illustrate the procedure using a spectacled eider (Somateria fischeri) data set of estimated annual abundances from aerial transect surveys conducted from 1957 to 1995. The analytic variance estimator provides a way to plan future studies to reduce uncertainty and bias in estimates of population growth rates. Demographic studies with policy implications or those involving species of conservation concern should especially consider the correlated nature of population trend data.
Keywords: Breeding Season; Somateria fischeri; Spectacled Eider; Abundance, Distribution, and Trends; Population Dynamics; Techniques

Predicting Waterbird Nest Distributions on the Yukon-Kuskokwim Delta of Alaska - Saalfeld, S. T.; Fischer, J. B.; Stehn, R. A.; Platte, R. M.; Brown, S. C. (JOURNAL OF WILDLIFE MANAGEMENT, 2017)
The Yukon-Kuskokwim Delta of Alaska, USAis a globally important region for numerous avian species including millions of migrating and nesting waterbirds. However, data on the current spatial distribution of critical nesting areas and the importance of environmental variables in the selection of nest locations are generally lacking for waterbirds in this region. We modeled nest densities for 6 species of geese and eiders that commonly breed on the Yukon-Kuskokwim Delta, including cackling goose (Branta hutchinsii minima), emperor goose (Chen canagica), black brant (B. bernicla nigricans), greater white-fronted goose (Anser albifrons frontalis), spectacled eider (Somateria fischeri), and common eider (S. mollissima). The data used were from single-visit nest searches on 2,318 plots sampled during 29 years from 1985 to 2013. We modeled nest density for each species by combining data across years and using random forests methods and time-static landscape environmental variables. These models provide the first habitat-specific predictive distributions of nest density for these species breeding on the Yukon-Kuskokwim Delta of Alaska. Predictive performance of the random forests models varied among species, explaining 13-69% of the variance in nest density. For most species, nest density was greatest near the coast and within lowland habitats. Predicted nest densities mapped across the coastal zone of the Yukon-Kuskokwim Delta revealed areas of high and low nest densities that can be used to inform management and conservation decisions. (C) 2017 The Wildlife Society.
Times Cited in Web of Science Core Collection: 5 Total Times Cited: 6 Cited Reference Count: 40
Keywords: waterfowl; Arctic; SELECTION; Alaska; eider; SEA; CLASSIFICATION; geese; waterbirds; ECOSYSTEMS; EMPEROR GEESE; HABITATS; nest density; predicted density surface; random forests; Yukon-Kuskokwim Delta

Nest habitat selection of White-winged Scoters on Yukon Flats, Alaska - Safine, David E.; Lindberg, Mark S. (Wilson Journal of Ornithology, 2008)
Breeding bird surveys indicate a long-term decline in numbers of scoters (Melanitta spp.) breeding in North America. Little is known about the breeding habitat and reproductive life history of White-winged Scoters (M. fusca) in their primary breeding areas in the boreal forest of Alaska and northern Canada. We characterized selection of nest habitats and attributes within those habitats by measuring variables at nests and random sites on the Yukon Flats National Wildlife Refuge, Alaska. White-winged Scoters avoided nesting in meadows. but nested ill Scrub or forested habitat types in proportion to their availability (chi(2)(5) = 9.7, P = 0.08). Nests of radio-marked females were farther from water and edge (+210 +/- 43 and + 10 +/- 4 m, respectively). and in slightly thicker cover (+6 +/- 4%) than nests located Without aid of radio transmitters. Females selected sites with more variable and abundant overhead and lateral cover, and sites closer to edge and water than random sites. The results imply nearly random use of scrub kind forested habitat types within the Study area, but selective use of attributes within those habitat types. This generalist approach to nest site selection at a larger scale may be all adaptive response to reduce detection by nest predators. Nests located without use of radio-marked females may not be representative of the population of nests at a study site. White-winged Scoters often selected nest sites with dense cover far from water. which may increase nest Survival. However. concealed sites are difficult for heavy-bodied birds to escape and females may be trading productivity against their own mortality.
Keywords: Breeding Season; Melanitta fusca; White-winged Scoter; Habitat; SDJV funded

Use of genetic mark-recapture to estimate breeding site fidelity and philopatry in a threatened sea duck population, Alaska-breeding Steller's eiders - Safine, D. E.; Lindberg, M. S.; Martin, K. H.; Talbot, S. L.; Swem, T. R.; Pearce, J. M.; Stellrecht, N. C.; Sage, G. K.; Riddle, A. E.; Fales, K.; Hollmen, T. E. (ENDANGERED SPECIES RESEARCH, 2020)
The Steller's eider Polysticta stelleri is a sea duck that breeds in Arctic tundra regions of Russia and Alaska (USA). The Alaska-breeding population is listed as 'threatened' under the US Endangered Species Act because of a perceived contraction of the breeding range in North America. Understanding demography of the listed population is critical for evaluating measures that can lead to increased abundance and thus, long-term viability. Specifically, estimates of return rates to breeding areas by adult females and natal areas by juvenile females are needed for planning effective recovery actions. We used a suite of polymorphic loci to genotype individuals and generated genetic profiles of nesting females and female offspring from nest materials collected between 1995 and 2016 in a similar to 170 km(2) study area near Utqiagvik, Alaska. We analyzed capture histories of genetically identified individuals to estimate breeding site fidelity, temporary emigration, and philopatry. From a sample of 365 nests, we found that breeding site fidelity of adult females was high (0.91 +/- 0.07 SE), and temporary emigration was also high (0.77 +/- 0.06) and annually variable (range 0.34-0.97). From egg shell remains of 124 hatched females, we observed 9 recaptures as nesting adults, suggesting that philopatry was also high (range 0.6-1.0). Given the relatively high rates of adult female breeding site fidelity and female philopatry that we estimated, management actions that reduce mortality of adult females and increase annual productivity are likely to help maintain the population of a few hundred breeding Steller's eiders on the Arctic Coastal Plain of Alaska.
Times Cited in Web of Science Core Collection: 1 Total Times Cited: 1 Cited Reference Count: 51
Keywords: COMMON EIDERS; MOVEMENTS; Polysticta stelleri; POLYSTICTA-STELLERI; ANNUAL SURVIVAL; YUKON-KUSKOKWIM DELTA; TRENDS; Apparent survival; Capture probability; Nest detection; PENINSULA; Temporary and permanent emigration

Characterization of H5N1 highly pathogenic avian influenza virus strains isolated from migratory waterfowl in Mongolia on the way back from the southern Asia to their northern territory - Sakoda, Yoshihiro; Sugar, Sengee; Batchluun, Damdinjav; Erdene-Ochir, Tseren-Ochir; Okamatsu, Masatoshi; Isoda, Norikazu; Soda, Kosuke; Takakuwa, Hiroki; Tsuda, Yoshimi; Yamamoto, Naoki; Kishida, Noriko; Matsuno, Keita; et al. (Virology, 2010)
H5N1 highly pathogenic avian influenza (HPAI) viruses were isolated from dead wild waterfowl at Khunt, Erkhel, Doityn Tsagaan, Doroo, and Ganga Lakes in Mongolia in July 2005, May 2006, May 2009, July 2009, and May 2010, respectively. The isolates in 2005 and 2006 were classified into genetic clade 2.2, and those in 2009 and 2010 into clade 2.3.2. A/whooper swan/Mongolia/6/2009 (H5N1) experimentally infected ducks and replicated systemically with higher mortality than that of the isolates in 2005 and 2006. Intensive surveillance of avian influenza in migratory waterfowl flying from their nesting lakes in Siberia to Mongolia in every autumn indicate that HPAI viruses have not perpetuated at their nesting lakes until 2009. The present results demonstrate that wild waterfowl were sporadically infected with H5N1 HPAI viruses prevailing in domestic poultry in the southern Asia and died in Mongolia on the way back to their northern territory in spring. (C) 2010 Elsevier Inc. All rights reserved.
Keywords: Breeding Season; Sea Ducks - General; Bucephala clangula; Common Goldeneye; Disease

Distribution and Abundance of Birds on the Arctic Coastal Plain of Northern Yukon and Adjacent Northwest-Territories Canada 1971-1976 - Salter, R. E.; Gollop, M. A.; Johnson, S. R.; Koski, W. R.; Tull, C. E. (Canadian Field-Naturalist, 1980)
Observations on avian distribution, abundance, habitat relationships and seasonal movements are summarized. A total of 122 spp. were recorded; at least 46 (and possibly an additional 14) nest in the area. Known breeding ranges of brant (Branta bernicla), mallard (Anas platyrhynchos), pintail (A. acuta), American wigeon (A. americana), northern shoveler (A. clypeata), scaup (Aythya spp.), pectoral sandpiper (Calidris melanotos), stilt sandpiper (Micropalama himantopus), buff-breasted sandpiper (Tryngites subruficollis), red phalarope (Phalaropus fulicarius). Say's phoebe (Sayornis saya), yellow wagtail (Motacilla flava), yellow warbler (Dendroica petechia), white-crowned sparrow (Zonotrichia leucophrys), and fox sparrow (Passerella iliaca) are extended. The study area is the main fall staging region for post-breeding snow geese (Chen caerulescens) of the western Canadian Arctic, and includes an important molting site for oldsquaws (Clangula hyemalis) and surf scoters (Melanitta perspicillata). The coast is a major migration route for various waterfowl and shorebirds. Only gyrfalcon (Falco rusticolus), willow ptarmigan (Lagopus lagopus), snowy owl (Nyctea scandiaca) and common raven (Corvus corax) remain during winter. The avifaunas of the Canadian and Alaskan portions of the coastal Plain are similar, with the primary exception that Asiatic, Beringian and maritime stragglers are confined largely to the Alaskan portion.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Sea Ducks - General; Nonbreeding Seasons

The food and habits of the American Merganser during winter in Michigan, considered in relation to fish management - Salyer, J. Clark, II; Lagler, Karl F. (Jour Wildlife Management, 1940)
Areas of maximum autumn and spring concs. for the American merganser (Mergus merganser americanus) in Michigan are the waters margining the northern half of the Lower Peninsula. During unusually cold or prolonged winters when these waters freeze over, large numbers of mergansers are forced onto inland waters, frequently trout streams. The food of 345 specimens from all types of fishing waters showed that the sp. at times on trout streams constitutes a serious menace to the sport fishery whereas on other natural waters it is either innocuous or beneficial. "Merganser drives" are described as a means for controlling concs. on trout streams. Mechanical devices which exclude or frighten mergansers are adequate for protecting fishes in rearing ponds. Feeding is largely diurnal and by sight; 1/3-1/2 of the body wt. is estimated as the average daily food consumption of wintering birds. Because of their food and habits, the Red-breasted (M. senator), and Hooded Mergansers (Lophodytes cucullatus) are considered to be of no importance to fish management in Michigan. || ABSTRACT AUTHORS: K. F. Lagler
Keywords: Conservation; Nonbreeding Seasons; Trophic Interactions; Common merganser; Mergus merganser

ACOUSTIC DIFFERENCES BETWEEN THE SCOTERS MELANITTA NIGRA NIGRA AND M. N. AMERICANA - Sangster, G. (WILSON JOURNAL OF ORNITHOLOGY, 2009)
Scoter vocalizations may have a role in pair formation and pair bonding. I compared the courtship calls of male Black Scoters (Melanitta nigra nigra and M. n. americana) using published and archived recordings. Courtship calls of the two subspecies differed diagnosably in duration. In contrast, recordings from different localities within the ranges of each taxon showed no diagnosable differentiation. This finding represents the first indication these taxa differ in characters other than bill morphology and supports recent proposals to treat M. it. americana as a distinct species (M. americana). Vocal displays, in contrast to courtship displays, of anatids have not been used for assessment of species limits in Anatidae. My results indicate vocalizations are a potentially useful additional character in species-level taxonomy of anatids. Received 7 September 2004. Accepted 10 May 2009.
Times Cited in Web of Science Core Collection: 4 Total Times Cited: 6 Cited Reference Count: 58
Keywords: SPECIES LIMITS

Taxonomic recommendations for Western Palearctic birds: 11th report - Sangster, G.; Collinson, J. M.; Crochet, P. A.; Kirwan, G. M.; Knox, A. G.; Parkin, D. T.; Votier, S. C. (Ibis, 2016)
Sangster, George Collinson, J. Martin Crochet, Pierre-Andre Kirwan, Guy M. Knox, Alan G. Parkin, David T. Votier, Stephen C.
Keywords: Taxonomy; Common Eider; Somateria mollissima

An occurrence of avian tuberculosis in hooded merganser (Lophodytes cucullatus) - Sato, Yoshihiko; Aoyagi, Takahiro; Matsuura, Shouhei; Fukui, Shigeto; Kitazawa, Isao; Nishimori, Kei; Yokomizo, Yuichi (Avian Diseases, 1996)
Two imported male hooded mergansers (Lophodytes cucullatus) were introduced into a zoological aviary in Japan, and one of them died 10 mo later. postmortem revealed numerous white yellowish nodules of various sizes in the liver. Two large nodules were also observed below the right lung and on the top of the left kidney. Histopathologically, a large number of tubercles with acid-fast bacilli were seen in the liver. The amyloid was deposited in the connective tissue of the tubercles. Bacteriologically, Mycobacterium avium serovar 1 was isolated from the liver.
Keywords: Disease; Hooded Merganser; Lophodytes cucullatus

Intraspecific and Interspecific Competition between Barrows Goldeneye Bucephala-Islandica and Bufflehead Bucephala-Albeola - Savard J-P, L. (Canadian Journal of Zoology, 1982)
Barrow's goldeneye and bufflehead pairs defend well-delineated territories from which they exclude conspecifics. Only the male defends the territory and does so even when the female is absent. After the young have hatched, females of both species defend brood territories from which they exclude conspecifics. Both species are also interspecifically territorial. Barrow's goldeneye and bufflehead drakes threatened and (or) attacked 15 and 11 spp., respectively. Of Barrow's goldeneye interspecific encounters, 55% were with bufflehead and 52% of bufflehead encounters were with Barrow's goldeneye. Barrow's goldeneye drakes always excluded bufflehead from their territory whereas bufflehead drakes successfully excluded yearlings, females and unpaired Barrow's goldeneye drakes but were usually dominated by paired males. Female Barrow's goldeneye excluded all bufflehead from the brood territory and were particularly aggressive toward bufflehead broods. Food and mates are the most likely defended resources in intraspecific encounters. In interspecific encounters diving ducks were more violently attacked than dabbling ducks indicating that food may be the defended resource. Interspecific aggression of Barrow's goldeneye toward bufflehead does not appear to be misdirected intraspecfic aggression but rather a directed aggression toward a food competitor and may be adaptive.
Keywords: Behavior; Breeding Season; Bucephala albeola; Bufflehead; Barrow's Goldeneye; Bucephala islandica

Territorial Behavior of Common Goldeneye Bucephala-Clangula Barrows Goldeneye Bucephala-Islandica and Bufflehead Bucephala-Albeola in Areas of Sympatry - Savard J-P, L. (Ornis Scandinavica, 1984)
Like barrow's goldeneye B. islandica and bufflehead B. albeola, comon goldeneye B. clangula defend territories on their breeding grounds. Territorial behavior of the 3 spp. is similar: paired drakes exclude all conspecifics but their mates from their territories; interactions with neighboring territorial drakes lst longer, are less violent and more ritualized than interactions with strangers. All 3 spp. are interspecifically territorial and interspecific confrontations are similar to intraspecific ones. Both goldeneyes dominate bufflehead. Barrow's goldeneye appear more aggressive than common goldeneye but neither species clearly dominate the other common goldeneye and bufflehead occur on both fresh and saline ponds whereas barrow's goldeneye prefer saline ones.
Keywords: Behavior; Breeding Season; Bucephala clangula; Common Goldeneye; Bucephala albeola; Bufflehead; Barrow's Goldeneye; Bucephala islandica

Evidence of Long-Term Pair Bonds in Barrows Goldeneye Bucephala-Islandica - Savard J-P, L. (Auk, 1985)
Keywords: Behavior; Barrow's Goldeneye; Bucephala islandica

Polygyny in Barrow's Goldeneye Bucephala-Islandica - Savard J-P, L. (Condor, 1986)
Keywords: Behavior; Breeding Season; Barrow's Goldeneye; Bucephala islandica

Causes and Functions of Brood Amalgamation in Barrow's Goldeneye and Bufflehead - Savard J-P, L. (Canadian Journal of Zoology, 1987)
I recorded 42 cases of brood amalgamation in Barrow's Goldeneye (Bucephala islandica) and 31 cases in Bufflehead (B. albeola). In four witnessed brood encounters, there was no evidence of behaviour facilitating brood amalgamation in either the young or the female. Females did not attempt to steal other females' young but rather tried to chase them away or even kill them. Females abandoned their young only after violent fights and often made several attempts to regain them. Brood encounters had various outcomes: (i) establishment of territorial boundaries, (ii) expulsion from lake, (iii) death of young, (iv) complete or partial brood amalgamation. In 3 years of observations there was no significant relationship between brood size and duckling survival. I contend that brood amalgamation in Barrow's Goldeneye and in Bufflehead has not evolved as an adaptation to increase young and (or) female survival but that it is simply an accidental outcome of territorial aggressiveness.
Keywords: Behavior; Breeding Season; Bucephala albeola; Bufflehead; Barrow's Goldeneye; Bucephala islandica

Winter Spring and Summer Territorality in Barrow's Goldeneye Characteristics and Benefits - Savard J-P, L. (Ornis Scandinavica, 1988)
Barrow's Goldeneye Bucephala islandica have a multi-stage territorial system, defending district pair, brood, and winter territories. Only paired birds defend winter territories and their territorial behaviour is similar to that observed on the breeding areas. Breeding pair territories averaged 0.44 ha (range: 0.05-1.85 ha) whereas brood territories averaged 0.91 ha (range: 0.27-2.79 ha). Breeding pair territories were not centered around the females but had well defined boundaries, and were defended even when the female was absent. Removal of two pairs suggests that territory size was determined mostly by pair density as territories expanded after the removals. Breeding pair and brood territories averaged approximately 0.35 km from the nest site (range: 0.2-9 km). Broods usually settled on the lake closest to the main advantage of spring and winter pair territoriality may be in providing an exclusive and undisturbed feeding area for the female. Similarly brood territories provide an exclusive feeding area for the young.
Keywords: Behavior; Breeding Season; Nonbreeding Seasons; Barrow's Goldeneye; Bucephala islandica

Use of Nest Boxes by Barrow's Goldeneyes Nesting Success and Effect on the Breeding Population - Savard J-P, L. (Wildlife Society Bulletin, 1988)
Keywords: Breeding Season; Techniques; Barrow's Goldeneye; Bucephala islandica

Survival and Breeding Philopatry in Barrow's and Common Goldeneyes - Savard J-P, L.; Eadie, J. M. (Condor, 1989)
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Dispersal; Survival; Barrow's Goldeneye; Bucephala islandica

Distribution Abundance and Aspects of Breeding Ecology of Black Scoters Melanitta Nigra and Surf Scoters Melanitta-Perspicillata in Northern Quebec - Savard J-P, L.; Lamothe, P. (Canadian Field-Naturalist, 1991)
In northern Quebec and Labrador, the breeding ranges of black scoter (Melanitta nigra) and surf scoter (M. perspicillata) correspond roughly to the subarctic zone. Near Lake Bienville, Quebec, black scoter broods were more abundant (4-14/100 km2) than those of surf scoters (2-5/100 km2), and higher than elsewhere in North America. Brood density estimates derived from single aerial surveys were nearly half those derived from repeated surveys of an area. The breeding chronology of both scoter species was similar with laying beginning in the first week of June and broods hatching in the 2nd and 3rd weeks of July. Duckling mortality was high. Newly hatched Surf scoters spent 60% of their time feeding whereas the attending females spent only 30%. Brood feeding periods (37.3 .+-. 3.6 minutes) were longer than resting periods (22.2 .+-. 4.1 minutes). Resting periods averaged longer on land (.hivin.x = 24.9 .+-. 2.8 minutes) than on water (.hivin.x = 15.4 .+-. 2.2 minutes). Timing of feeding and resting activities probably affect the accuracy of aerial surveys for scoters on the breeding grounds.
Keywords: Behavior; Breeding Season; Abundance, Distribution, and Trends; Melanitta perspicillata; Surf Scoter; Black Scoter; Melanitta nigra

Duckling Mortality in Barrow's Goldeneye and Bufflehead Broods - Savard J-P, L.; Smith, G. E. J.; Smith, J. N. M. (Auk, 1991)
We compared duckling mortality patterns in Barrow's Goldeneyes (Bucephala islandica) and Buffleheads (B. albeola) in the aspen parkland of central British Columbia, Canada. Hatching phenology of both species varied between years in relation to spring temperatures. Buffleheads hatched on average a few days later than Barrow's Goldeneyes each year. Mortality estimates for duckling differed by as much as 55%, and depended on the technique used. Estimates of mortality rates per brood were higher and more variable than those calculated per duckling. The Mayfield estimate of mortality per duckling day, adjusted for duckling age, was the most accurate. Mortality rates of Barrow's Goldeneyes and Buffleheads varied similarly between years. Mortality patterns in relation to duckling age, however, varied between species and between years. The highest mortality usually occurred in the week after hatching. Hatching date influenced mortality rates in 3 of 5 yr, but there was no consistent pattern. Barrow's Goldeneye ducklings suffered higher mortality than Bufflehead ducklings in 4 of 5 yr. This pattern was reversed in 1984, when the largest number of Barrow's Goldeneye broods occurred. Duckling mortality was higher on ponds with several broods than on ponds with single broods, which implies density-dependent mortality. This may have been due to intra- and interspecific aggression. The high mortality of Barrow's Goldeneye ducklings in 1983 was followed by lowered female recruitment in 1985. Because aggressiveness by Barrow's Goldeneyes has more impact on conspecifics, Barrow's Goldeneyes and Buffleheads can coexist at low to moderate densities of goldeneyes. At high goldeneyes densities, Buffleheads may be excluded from some ponds.
Keywords: Breeding Season; Survival; Bucephala albeola; Bufflehead; Barrow's Goldeneye; Bucephala islandica

Interspecific Aggression by Barrow's Goldeneye a Descriptive and Functional Analysis - Savard J-P, L.; Smith, J. N. M. (Behaviour, 1987)
We describe interspecific aggression and territoriality by a diving duck, the Barrow's goldeneye. Males of this species are strongly interspecifically territorial early during the breeding season, and in winter. Females are interspecifically territorial while tending broods of ducklings. Aggression was strongest against conspecifics, and against the congeneric bufflehead, which shares the same breeding habitat. Other diving ducks, which overlap in diet with goldeneyes, were frequently attacked, while dabbling ducks, with differing feeding habits, were generally tolerated, and were seldom attacked. One dabbling duck, the blue-winged teal, in which the drake resembles the Barrow's goldeneye drake in plumage, was attacked more strongly than other dabblers. We propose that the strong interspecific aggressiveness exhibited by the Barrow's goldeneye, and its congeners the bufflehead and common goldeneye, is a consequence of the strong intraspecific aggressiveness of these species. Selectivity in aggression towards victims of different species can be explained by two hypotheses. Species that have (1) similar diets, and (2) similar plumages to Barrow's goldeneye was selectively attacked.
Keywords: Behavior; Breeding Season; Barrow's Goldeneye; Bucephala islandica

Remigial molt of sea ducks - Savard, J.-P. L. and M. R. Petersen (Studies in Avian Biology, 2015)
Molt is a dynamic process occurring throughout much of the year in waterfowl. The molt of flight feathers by waterfowl, especially sea ducks, however, occurs over a compressed period of time and in specific areas used each year. We provide an overview of the flight feather molt of sea ducks. We focus on the need to molt and why, the timing and duration of flight feather molt, and the duration birds remain at molting areas; energetics of molt and strategies for managing energetic needs; molt migration; food resources and foraging behavior; predation risks; temporal constraints and competition; response to disturbance; and molt habitats and seasonal differences in habitat used by sea ducks. We conclude by presenting and discussing data gaps and emphasize the continuing need for a holistic approach to sea duck management and international cooperation among countries.
Keywords: Behavior; Molt; Energetics and Nutrition; Habitat

Waterfowl-wetland relationships in the Aspen Parkland of British Columbia: Comparison of analytical methods - Savard, Jean-Pierre L.; Boyd, W. Sean; Smith, G. E. John (Hydrobiologia, 1994)
We explored the relationships between aquatic bird abundance and various pond features (physical and chemical) using data from 112 ponds located in the Aspen Parkland of British Columbia. As expected, pond size was the most important factor influencing the number of aquatic birds present. Total dissolved nitrogen, conductivity and calcium were positively associated with the abundance of several species whereas chloride tended to be negatively associated. The abundance of dabbling ducks was positively associated with turbidity and total dissolved nitrogen and negatively with percent of forested shoreline, percent of marsh and chloride. The abundance of diving ducks was associated positively with pond depth, conductivity and total dissolved nitrogen and negatively with percent of marsh and phosphorus levels. Pond area influenced more the abundance of diving ducks than dabbling ducks. Relationships between bird density and pond features were affected significantly by the area unit used to calculate density. For example, the density of Bufflehead (Bucephala albeola) was correlated positively with pH and conductivity when expressed per area of water 0-2 m deep but negatively ,%,hen expressed per total area of pond. Results highlight the problems associated with interpreting correlative type studies especially the difficulties in assessing the biological significance of the observed correlations. It underscores the urgent need for experimental approaches to bird-habitat studies.
Keywords: Breeding Season; Abundance, Distribution, and Trends; Sea Ducks - General; Habitat

Chronology of breeding and molt migration in surf scoters (Melanitta perspicillata) - Savard, Jean-Pierre L.; Reed, Austin; Lesage, Louis (Waterbirds, 2007)
Little is known about the molt migration of the Surf Scorer (Melanitta perspicillata), a species endemic to North America. Our objective in this study was to document the breeding and molting chronology of Surf Scoters in Quebec. Breeding birds were studied at Lake Malbaie, located about 90 km north of Quebec City, Canada. Surf Scorers arrived at Lake Malbaie in the fourth week of May and most males stayed only for approximately three weeks. This relatively early departure of males from the breeding areas emphasizes the importance of saltwater habitats for these birds. Unsuccessful adult females did not leave with the males but remained on their breeding lake. These females left the lake from mid to late July, nearly a month after the departure of males and much earlier than females with broods which left from mid to late August after abandoning their brood. This departure sequence was observed during the three years of the study. The difference in timing of molt migration between age and sex groups has important management implications as it potentially exposes them to different levels of mortality. For example, late molters, mostly adult females that bred successfully may still be flightless at the beginning of the hunting season in some areas. Better understanding of molt chronology and habitat selection by various sex and age groups will permit a more holistic and efficient management of Surf Scoters.
Keywords: Breeding Season; Melanitta perspicillata; Surf Scoter; Migration

Use of nest boxes by Goldeneyes in eastern North America - Savard, Jean-Pierre L.; Robert, Michel (Wilson Journal of Ornithology, 2007)
We evaluated and monitored use of 105-133 nest boxes by Common Goldeneye (Bucephala clangula) and Barrow's Goldeneye (Bucephala islandica) during 1999-2004 on 60 lakes of high plateaus of the Laurentian Highlands, in the boreal forest of Quebec, Canada. Only three species of birds used nest boxes regularly, American Kestrel (Falco sparverius), Barrow's Goldeneye, and Common Goldeneye. The proportion of nest boxes used by goldeneyes in 2000-2004 ranged from 23 to 43% whereas hatching success ranged from 37 to 67%. Successful Barrow's and Common goldeneye clutches averaged 6.76 +/- 0.38 (SE, n = 29) and 7.77 +/- 0.44 eggs (n = 31), respectively. Predation in nest boxes was not a major mortality factor. Goldeneyes used all nest boxes independent of their location but reproductive success was lower in nest boxes 25-160 m from shore in clearcuts. The number of Barrow's and Common goldeneye breeding pairs increased between 1999 and 2003, but number of broods remained stable after an increase in 2000.
Keywords: Breeding Season; Bucephala clangula; Common Goldeneye; Techniques; SDJV funded; Barrow's Goldeneye; Bucephala islandica

Harlequin Ducks in Quebec - Savard, Jean-Pierre L.; Robert, Michel; Brodeur, Serge (Waterbirds, 2008)
In the last decade, several survey and research efforts have been undertaken to better understand the ecology and distribution of Harlequin Ducks (Histrionicus histrionicus) in Quebec. The results of these efforts are summarized and new survey, research and management needs arc identified. Harlequin Ducks breed oil rivers and streams of the Gaspe Peninsula, the Quebec North Shore, and the immense Hudson Bay and Ungava Bay drainage basins. Quebec is possibly the most important breeding area for Harlequin Ducks in eastern Canada, and there is every indication that a significant proportion of the birds wintering in south-western Greenland and in eastern North America breed in Quebec. In spring, significant numbers of birds spend a few days or weeks along the Gaspe Peninsula before departing for their breeding or molting areas. The most important molting sites in Quebec are Bonaventure Island, the Port-Daniel/New-port area, and the Pointe du Sud-Onset/Jupiter River area oil Anticosti Island. Known fall staging areas include the coastal waters of the Gaspe Peninsula, the Pointe du Sud-Ouest/Jupiter River area, and Brion Island, oil the Magdalen Islands. The few Harlequin Ducks that overwinter in Quebec are mostly in Baie des Chaleurs, oil the south shore of the Gaspe Peninsula. There are no good data on trends; of Harlequin Ducks' in Quebec. Major threats to population recovery/health include hydroelectric development,,, illegal mid subsistence harvests, coastal exploitation (aquaculture, fisheries, boating), and recreational activities on breeding rivers and streams. Survey, research and management needs include better estimates of breeding densities and distribution, characterization of spring, summer and fall coastal habitats, comprehensive generic analysis, monitoring, and Public education oil the status of Harlequin Ducks.
Keywords: Breeding Season; Nonbreeding Seasons; Harlequin duck; Histrionicus histrionicus

Molting, Staging, and Wintering Locations of Common Eiders Breeding in the Gyrfalcon Archipelago, Ungava Bay - Savard, J. P. L.; Lesage, L.; Gilliland, S. G.; Gilchrist, H. G.; Giroux, J. F. (Arctic, 2011)
Times Cited: 0 Savard, Jean-Pierre L. Lesage, Louis Gilliland, Scott G. Gilchrist, H. Grant Giroux, Jean-Francois 0
Keywords: migration; Breeding Season; Nonbreeding Seasons; Common eider; somateria mollissima; habitat; population delineation

Brood amalgamation in Surf Scoters Melanitta perspicillata and other Mergini - Savard, J. P. L.; Reed, A.; Lesage, L. (Wildfowl, 1999)
Brood amalgamation is frequent within the Tribe Mergini. We quantified amalgamation in the Surf Scoter (Melanitta perspicillata) by a combination of observations on marked and unmarked broods at Lake Malbaie, Quebec. Brood amalgamation was frequent, especially when brood density was high. Broods, amalgamated or not, were always tended by a single female. Lone females sometimes associated with broods for short periods of time, but occasionally threatened and attacked young. Most often, lone females were chased off by the attending female. Females with young did not try to attract other young and were quite aggressive towards strange young. No behaviour suggesting any voluntary abandonment of young by females was observed. Brood amalgamation in this population apparently occurred accidentally, presumably favoured by crowding, a variable level of aggressiveness between females and apparently weak female-young bonds. A review of the literature on brood amalgamation in the tribe Mergini supports these findings.
Keywords: Behavior; Breeding Season; Melanitta perspicillata; Surf Scoter

Relationships among Breeding, Molting and Wintering Areas of Adult Female Barrow's Goldeneyes (Bucephala islandica) in Eastern North America - Savard, J. P. L.; Robert, M. (Waterbirds, 2013)
Times Cited: 0 Savard, Jean-Pierre L. Robert, Michel 0
Keywords: Breeding Season; Nonbreeding Seasons; Migration; SDJV funded; Barrow's Goldeneye; Bucephala islandica; Population Delineation