Nesting Common Eider (Somateria mollissima) Population Quintuples in Northwest Greenland

Common eider (Somateria mollissima) populations in Greenland severely declined throughout the 20th century. As a result, in 2001, harvest regulations were changed and the length of the hunting season was reduced. Recent data suggest that these changes have been successful, and population regrowth is occurring. In the Avanersuaq District, northwest Greenland, only one systematic survey quantifying the number of nesting eiders had previously been conducted, in 1997 and 1998. Although this district had historically been identified as having the largest number of breeding eiders in Greenland, the 1997–98 survey results showed a relatively small estimated population of 5000 pairs. However, it is not known to what extent changes in hunting regulations have affected nesting abundance in this area. Therefore, the Avanersuaq District was systematically resurveyed during the 2009 breeding season, approximately 11 years after the previous survey. These results showed that the population had increased to 5.4 times its 1997–98 size, with an annual compounded growth rate of 15.3%. On a single island, nearly 4500 active nests were observed. Five islands had more than 2600 nests each and comprised 75% of the total nests counted. Along with historical information to account for additional nesting habitat not surveyed, the observed population growth rate from this study suggests that the overall Avanersuaq common eider breeding population size ranges from 25 000 to 30 000 pairs, or roughly half of the total estimated West Greenland breeding population. Despite the significance of the Avanersuaq District as a breeding area for common eiders, we have only limited information about this population. The effects of recent extensions of the hunting season on this population are also unknown, and the only wintering location information is based on a few individuals banded in the 1920s and 1940s. Additional research on migratory movements is suggested before any further changes are made to hunting regulations.Au cours du XXe siècle, les populations d’eiders à duvet (Somateria mollissima) ont connu un déclin considérable au Groenland. C’est pourquoi en 2001, le règlement relatif à la chasse a été modifié et la saison de chasse a été raccourcie. Selon des données récentes, ces changements ont porté fruits en ce sens que la population s’est accrue. Dans le district d’Avanersuaq, dans le nord-ouest du Groenland, seulement un relevé systématique ayant pour but de quantifier le nombre d’eiders nicheurs a été fait, et c’était en 1997-1998. Bien qu’au fil des ans, ce district a compté le plus grand nombre d’eiders reproducteurs du Groenland, le relevé de 1997-1998 avait établi que la population était relativement petite, avec une estimation de 5 000 paires. On ne sait toutefois pas dans quelle mesure la modification du règlement sur la chasse a eu des effets sur l’abondance d’eiders nichant dans la région. Par conséquent, le district d’Avarsuaq a systématiquement fait l’objet d’un autre relevé pendant la saison de reproduction de 2009, soit environ 11 ans après le relevé d’origine. Les résultats ont permis de constater que la population s’était accrue dans une mesure de 5,4 fois par rapport à sa taille de 1997-1998, ce qui correspondait à un taux d’accroissement annuel composé de 15,3 %. Sur une seule île, près de 4 500 nids actifs ont été observés. Cinq îles comptaient plus de 2 600 nids par île, ce qui représentait 75 % du nombre total de nids répertoriés. Jumelé aux données historiques tenant compte de l’habitat de nidification supplémentaire et non relevé, le taux d’accroissement de la population observé à partir de cette étude suggère que la taille de la population globale d’eiders à duvet nicheurs d’Avanersuaq varie de 25 000 à 30 000 paires, ce qui correspond à environ la moitié du total estimé de la population nicheuse de l’ouest du Groenland. Malgré l’importance que revêt le district d’Avanersuaq comme aire de reproduction de l’eider à duvet, nous ne possédons que des renseignements restreints au sujet de cette population. Les effets qu’aura le prolongement récent de la saison de chasse sur cette population sont également inconnus, et la seule information concernant la localisation de l’aire d’hivernage dont nous disposons a trait à quelques individus qui avaient été bagués dans les années 1920 et 1940. Par conséquent, il est suggéré de pousser les recherches relatives aux mouvements migratoires plus loin avant d’apporter d’autres changements au règlement de chasse

Genetics of plumage color in the gyrfalcon (Falco rusticolus): analysis of the melanocortin-1 receptor

Abstract Genetic variation at the melanocortin-1 receptor (MC1R) gene is correlated with melanin color variation in a few reported vertebrates. In Gyrfalcon (Falco rusticolus), plumage color variation exists throughout their arctic and subarctic circumpolar distribution, from white to gray and almost black. Multiple color variants do exist within the majority of populations; however, a few areas (e.g., northern Greenland and Iceland) possess a single color variant. Here, we show that the white/ melanic color pattern observed in Gyrfalcons is explained by allelic variation at MC1R. Six nucleotide substitutions in MC1R resulted in 9 alleles that differed in geographic frequency with at least 2 MC1R alleles observed in almost all sampled populations in Greenland, Iceland, Canada, and Alaska. In north Greenland, where white Gyrfalcons predominate, a single MC1R allele was observed at high frequency (.98%), whereas in Iceland, where only gray Gyrfalcons are known to breed, 7 alleles were observed. Of the 6 nucleotide substitutions, 3 resulted in amino acid substitutions, one of which (Val 128 Ile) was perfectly associated with the white/melanic polymorphism. Furthermore, the degree of melanism was correlated with number of MC1R variant alleles, with silver Gyrfalcons all heterozygous and the majority of dark gray individuals homozygou

Lead Bullet Fragments in Venison from Rifle-Killed Deer: Potential for Human Dietary Exposure

Human consumers of wildlife killed with lead ammunition may be exposed to health risks associated with lead ingestion. This hypothesis is based on published studies showing elevated blood lead concentrations in subsistence hunter populations, retention of ammunition residues in the tissues of hunter-killed animals, and systemic, cognitive, and behavioral disorders associated with human lead body burdens once considered safe. Our objective was to determine the incidence and bioavailability of lead bullet fragments in hunter-killed venison, a widely-eaten food among hunters and their families. We radiographed 30 eviscerated carcasses of White-tailed Deer (Odocoileus virginianus) shot by hunters with standard lead-core, copper-jacketed bullets under normal hunting conditions. All carcasses showed metal fragments (geometric mean = 136 fragments, range = 15–409) and widespread fragment dispersion. We took each carcass to a separate meat processor and fluoroscopically scanned the resulting meat packages; fluoroscopy revealed metal fragments in the ground meat packages of 24 (80%) of the 30 deer; 32% of 234 ground meat packages contained at least one fragment. Fragments were identified as lead by ICP in 93% of 27 samples. Isotope ratios of lead in meat matched the ratios of bullets, and differed from background lead in bone. We fed fragment-containing venison to four pigs to test bioavailability; four controls received venison without fragments from the same deer. Mean blood lead concentrations in pigs peaked at 2.29 µg/dL (maximum 3.8 µg/dL) 2 days following ingestion of fragment-containing venison, significantly higher than the 0.63 µg/dL averaged by controls. We conclude that people risk exposure to bioavailable lead from bullet fragments when they eat venison from deer killed with standard lead-based rifle bullets and processed under normal procedures. At risk in the U.S. are some ten million hunters, their families, and low-income beneficiaries of venison donations

The Use of Genetics for the Management of a Recovering Population: Temporal Assessment of Migratory Peregrine Falcons in North America

Background: Our ability to monitor populations or species that were once threatened or endangered and in the process of recovery is enhanced by using genetic methods to assess overall population stability and size over time. This can be accomplished most directly by obtaining genetic measures from temporally-spaced samples that reflect the overall stability of the population as given by changes in genetic diversity levels (allelic richness and heterozygosity), degree of population differentiation (FST and DEST), and effective population size (Ne). The primary goal of any recovery effort is to produce a longterm self-sustaining population, and these genetic measures provide a metric by which we can gauge our progress and help make important management decisions. Methodology/Principal Findings: The peregrine falcon in North America (Falco peregrinus tundrius and anatum) was delisted in 1994 and 1999, respectively, and its abundance will be monitored by the species Recovery Team every three years until 2015. Although the United States Fish and Wildlife Service makes a distinction between tundrius and anatum subspecies, our genetic results based on eleven microsatellite loci suggest limited differentiation that can be attributed to an isolation by distance relationship and warrant no delineation of these two subspecies in its northern latitudinal distribution from Alaska through Canada into Greenland. Using temporal samples collected at Padre Island, Texas during migration (seven temporal time periods between 1985–2007), no significant differences in genetic diversity or significant population differentiation in allele frequencies between time periods were observed and were indistinguishable from those obtained from tundrius/anatum breeding locations throughout their northern distribution. Estimates of harmonic mean Ne were variable and imprecise, but always greater than 500 when employing multiple temporal genetic methods. Conclusions/Significance: These results, including those from simulations to assess the power of each method to estimate Ne, suggest a stable or growing population, which is consistent with ongoing field-based monitoring surveys. Therefore, historic and continuing efforts to prevent the extinction of the peregrine falcon in North America appear successful with no indication of recent decline, at least from the northern latitude range-wide perspective. The results also further highlight the importance of archiving samples and their use for continual assessment of population recovery and long-term viability

Seasonal differences of corticosterone metabolite concentrations and parasite burden in northern bald ibis (Geronticus eremita): The role of affiliative interactions

The reproductive season is energetically costly as revealed by elevated glucocorticoid concentrations, constrained immune functions and an increased risk of infections. Social allies and affiliative interactions may buffer physiological stress responses and thereby alleviate associated effects. In the present study, we investigated the seasonal differences of immune reactive corticosterone metabolite concentrations, endoparasite burden (nematode eggs and coccidian oocysts) and affiliative interactions in northern bald ibis (Geronticus eremita), a critically endangered bird. In total, 43 individually marked focal animals from a freeranging colony were investigated. The analyses included a description of initiated and received affiliative interactions, pair bond status as well as seasonal patterns of hormone and endoparasite levels. During the reproductive season, droppings contained parasite eggs more often and corticosterone metabolite levels were higher as compared to the period after reproduction. The excretion rate of endoparasite products was lower in paired individuals than in unpaired ones, but paired animals exhibited higher corticosterone metabolite concentrations than unpaired individuals. Furthermore, paired individuals initiated affiliative behaviour more frequently than unpaired ones. This suggests that the reproductive season influences the excretion patterns of endoparasite products and corticosterone metabolites and that affiliative interactions between pair partners may positively affect endoparasite burden during periods of elevated glucocorticoid levels. Being embedded in a pair bond may have a positive impact on individual immune system and parasite resistance

Heart Rate during Conflicts Predicts Post-Conflict Stress-Related Behavior in Greylag Geese

Background: Social stressors are known to be among the most potent stressors in group-living animals. This is not only manifested in individual physiology (heart rate, glucocorticoids), but also in how individuals behave directly after a conflict. Certain ‘stress-related behaviors ’ such as autopreening, body shaking, scratching and vigilance have been suggested to indicate an individual’s emotional state. Such behaviors may also alleviate stress, but the behavioral context and physiological basis of those behaviors is still poorly understood. Methodology/Principal Findings: We recorded beat-to-beat heart rates (HR) of 22 greylag geese in response to agonistic encounters using fully implanted sensor-transmitter packages. Additionally, for 143 major events we analyzed the behavior shown by our focal animals in the first two minutes after an interaction. Our results show that the HR during encounters and characteristics of the interaction predicted the frequency and duration of behaviors shown after a conflict. Conclusions/Significance: To our knowledge this is the first study to quantify the physiological and behavioral responses to single agonistic encounters and to link this to post conflict behavior. Our results demonstrate that ‘stress-related behaviors’ are flexibly modulated by the characteristics of the preceding aggressive interaction and reflect the individual’s emotional strain, which is linked to autonomic arousal. We found no support for the stress-alleviating hypothesis, but we propose tha

Inter- and intraspecific variation of breeding biology, movements, and genotype in Peregrine Falcon Falco peregrinus and Gyrfalcon F. rusticolus populations in Greenland

Peregrines Falco peregrinus and Gyrfalcons F. rusticolus were studied in Low and High Arctic Greenland, comparing populations within and between areas. Analyses of weather data from northwest Greenland (1979–2005) revealed a general warming trend, resulting in a lengthened breeding window for many bird species. Both falcon species depend on cliffs for nesting, and take a similar range of bird species as prey. However, Gyrfalcons lay six weeks earlier than Peregrines in Kangerlussuaq and one month earlier than Peregrines in Thule, and occupy more sheltered nest-sites. Being larger than Peregrines, Gyrfalcons also take some larger prey species. In addition, both species move to lower latitudes for the winter, but while most Gyrfalcons migrate relatively short distances, Peregrines are complete long-distance migrants to Central and South America. One Peregrine, satellite-tracked from its breeding site at 76.5° N, travelled ~12,500 km and &gt;100° in latitude, one of the longest migrations ever documented for a raptor.Around Thule in northwest Greenland (at 76.5° N), scientists had historically documented no breeding Peregrines, but six occupied sites were discovered during this study, comprising what is probably the most northern nesting population in the world. Over the same period, breeding Gyrfalcons have apparently disappeared from southern Greenland, and may have declined in central-west Greenland (67° N). The ultimate cause of this retraction may be climate warming, but the proximate cause is probably competition from an increasing Peregrine population.Gyrfalcons tagged with satellite-received transmitters showed characteristics associated with both obligate and facultative migration. Their winter ranges varied greatly in size, with the largest, ~172,000 km2, being the biggest ever documented for a raptor. Many individuals made long movements within a winter, and some spent up to a month at sea. They may have rested on ice and fed upon seabirds. Carbon dating of stratified faecal accumulation from Gyrfalcon nests in central-west and northwest Greenland showed use of sites for up to ~2,500 and ~650 years, respectively. The age of nest sites correlated significantly with the current distance to the Greenland Ice Sheet, and probably reflects colonization patterns following glacial retreat.In central-west Greenland the ratio of Peregrine to Gyrfalcon pairs changed from 1:1 in the early 1970s to nearly 14:1 in 2005. Over this period, competition for nest sites and prey is likely to have intensified. The crucial prey for Gyrfalcons when they start nesting in early spring are resident ptarmigan, whose numbers are probably depleted by Peregrines during the months they are present. If recent trends in climate change continue, Peregrines may continue to increase in Greenland, and spread north into areas previously occupied only by Gyrfalcons. At the same time, Gyrfalcons may retreat north from many currently-occupied areas.</p

Seasonal movements of Gyrfalcons Falco rusticolus include extensive periods at sea

Little information exists on the movements of Gyrfalcons Falco rusticolus outside the breeding season, particularly amongst High Arctic populations, with almost all current knowledge based on Low Arctic populations. This study is the first to provide data on summer and winter ranges and migration distances. We highlight a behaviour previously unknown in Gyrfalcons, in which birds winter on sea ice far from land. During 2000-2004, data were collected from 48 Gyrfalcons tagged with satellite transmitters in three parts of Greenland: Thule (northwest), Kangerlussuaq (central-west) and Scoresbysund (central-east). Breeding home-range size for seven adult females varied from 140 to 1197 km(2) and was 489 and 503 km(2) for two adult males. Complete outward migrations from breeding to wintering areas were recorded for three individuals: an adult male which travelled 3137 km over a 38-day period (83 km/day) from northern Ellesmere Island to southern Greenland, an adult female which travelled 4234 km from Thule to southern Greenland (via eastern Canada) over an 83-day period (51 km/day), and an adult female which travelled 391 km from Kangerlussuaq to southern Greenland over a 13-day period (30 km/day). Significant differences were found in winter home-range size between Falcons tagged on the west coast (383-6657 km(2)) and east coast (26 810-63 647 km(2)). Several Falcons had no obvious winter home-ranges and travelled continually during the non-breeding period, at times spending up to 40 consecutive days at sea, presumably resting on icebergs and feeding on seabirds. During the winter, one juvenile female travelled over 4548 km over an approximately 200-day period, spending over half that time over the ocean between Greenland and Iceland. These are some of the largest winter home-ranges ever documented in raptors and provide the first documentation of the long-term use of pelagic habitats by any falcon. In general, return migrations were faster than outward ones. This study highlights the importance of sea ice and fjord regions in southwest Greenland as winter habitat for Gyrfalcons, and provides the first detailed insights into the complex and highly variable movement patterns of the species

Morphological measurements of Atlantic puffin (Fratercula arctica naumanni) in High-Arctic Greenland

Morphological measurements of 45 adult Atlantic puffins&nbsp;Fratercula arctica&nbsp;were collected in High-Arctic Greenland between 2010 and 2016. Measurements support that the population belongs to the&nbsp;F. a. naumanni&nbsp;subspecies and were significantly larger than those from populations found at lower latitudes, including&nbsp;F. a. grabae&nbsp;and&nbsp;F. a. arctica&nbsp;populations. Male puffins from High-Arctic Greenland had greater mass, bill length and tarsus length than females, but no difference was found in wing length. In comparison to other&nbsp;naumanii&nbsp;populations, body size was most similar to puffins in Svalbard. Overall, the measured Atlantic puffins from High-Arctic Greenland had some of the largest and most variable morphological measurements reported for any studied Atlantic puffin population. While morphological measurements and the relative geographic isolation of the puffin population in High-Arctic Greenland support the&nbsp;naumanni&nbsp;subspecies designation, additional research should use genetic methods to determine if this population and other populations in the North Atlantic are isolated. This is the only collection of&nbsp;naumanni&nbsp;morphometric measurements from geographical North America and enhances our collective knowledge of the species