Breeding Biology of Red-throated Loons in the Canadian Beaufort Sea Region

The breeding biology of the red-throated loon in the Canadian Beaufort Sea region was investigated 1985 to 1989. Five study plots were established with a total area of 276 sq. km and over 200 pairs of loons on territory each breeding season. Loon densities ranged from 0.6 pairs/sq. km on the Yukon coast to 1.8 pairs/sq. km at Toker Point on the Tuktoyaktuk Peninsula. An average of 73% of the pairs on territory nested each year. Productivity averaged 0.63 young/nesting pair. The median date of egg laying ranged from 19 to 24 June in four years, but was 3 July in a year when spring thaw was late. The chicks fledged a mean of 47 d after hatch (n=10), the first clutch chicks leaving the nesting pond in late August to mid-September. In all but one year, the mortality rate was higher for eggs than chicks, with egg losses peaking in the second half of incubation. Most (82%) chick losses occurred within three weeks of hatch (n=61). Just 13% of the ponds were occupied in all five years of the study, while 39% were used in only one year. At two of the study plots, ponds with pairs that successfully reared at least one chick had a greater tendency to be occupied the following year than did ponds with unsuccessful pairs. At the other three plots, reuse of ponds was independent of breeding success the previous year.Key words: red-throated loon (Gavia stellata), breeding biology, Beaufort SeaOn a étudié la reproduction du huart à gorge rousse dans la partie canadienne de la mer de Beaufort de 1985 à 1989. À chacune des périodes de reproduction, on a observé plus de 200 couples de huarts territoriaux répartis dans cinq zones expérimentales couvrant une superficie totale de 276 km². La densité des huarts a varié de 0.6 couple par km² sur la côte du Yukon à 1.8 couple par km² à Toker Point sur la péninsule de Tuktoyaktuk. Le nombre moyen annuel de couples nicheurs territoriaux s'est élevé à 73%. La productivité moyenne a été de 0.63 oisillon par couple nicheur. La date médiane de ponte s'est située du 19 au 24 juin pour quatre des cinq années; l'autre année la date médiane de ponte a été le 3 juillet à cause d'un dégel printanier tardif. Le premier vol des oisillons a eu lieu en moyenne 47 jours après l'éclosion (n = 10), la première couvée quittant l'étang de nidification entre la fin août et la mi-septembre. À l'exception d'une année, le taux de mortalité a toujours été plus élevé dans le cas des oeufs que dans celui des oisillons et a été maximal pendant la deuxième moitié de l'incubation. La mortalité des oisillons a particulièrement été forte (82%) au cours des trois premières semaines suivant l'éclosion (n = 61). Seuls 13% des étangs ont été utilisés pendant les cinq années de l'étude alors que 39% l'ont été pendant seulement une année. Le succès de la reproduction n'a eu un effet sur la réutilisation d'un étang l'année suivante que dans deux des cinq zones expérimentales.Mots clés: huart à gorge rousse (Gavia stellata), reproduction, mer de Beaufor

Spring Migration and Subsistence Hunting of King and Common Eiders at Holman, Northwest Territories, 1996-98

A subsistence hunt for eiders by Innuvialuit of Holman, Northwest Territories, was observed over three spring harvest seasons from 1966 to 1998 to determine rates of crippling loss and to assess the sustainability of the harvest. King eiders (Somateria spectabilis) are the dominant waterfowl species harvested. The number of king eiders estimated to migrate past Holman in spring varied from 40 696 ± 4461 (95% confidence interval) in 1996 to 70 018 ± 14 356 in 1998, averaging 53 000 per year. Common eiders (Somateria mollissima v-nigra) were much less abundant, varying from 2728 ± 631 to 6017 ± 770 birds, averaging 4400 annually. Peak numbers of king eiders moved through the study area in 1-8 days during the second to third week of June in all years, and common eiders peaked in 1-8 days during the first to second week of June. Strong winds may have hindered migration for a few days. Crippling loss rates during the hunt were low (3-9%) in the first two years of the study, but increased to 13-20% in the early open-water spring of 1998, when hunters were forced to shoot over open water rather than shorefast ice. On the basis of these estimates and harvest data from the Inuvialuit Harvest Study, we determined that Holman hunters removed 3.7-6.9% of the king eider subpopulation and less than 1% of the common eiders over the three-year study period. The present level of harvest of eiders available to Holman hunters is likely sustainable. However, more information on natural mortality and recruitment rates, particularly for king eiders, is needed to confirm this.La chasse de subsistance à l'eider menée par les Inuvialuit de Holman (Territoires du Nord-Ouest) a fait l'objet d'un étude sur les trois saisons de récoltes printanières allant de 1996 à 1998, afin de déterminer les taux de pertes dues aux blessures et d'évaluer la viabilité de la récolte. L'eider à tête grise (Somateria spectabilis) représente la plus importante espèce de sauvagine récoltée. L'estimation du nombre d'eiders à tête grise passant près d'Holman durant la migration printanière variait de 40 696 ± 4461 (intervalle de confiance de 95 p.cent) en 1996 à 70 018 ± 14356 en 1998, soit une moyenne annuelle de 53 000. L'eider à duvet (Somateria mollissima v-nigra) était beaucoup moins abondant, variant de 2728 ± 631 à 6017 ± 770 individus, soit une moyenne annuelle de 4400. Le nombre d'eiders à tête grise passant dans la zone d'étude atteignait chaque année son apogée durant 1 à 8 jours pendant la deuxième et la troisième semaine de juin, et celui des eiders à duvet durant 1 à 8 jours pendant la première quinzaine de juin. Il se peut que des vents forts aient entravé la migration pendant quelques jours. Le taux de pertes dues aux blessures survenues au cours de la chasse était faible (de 3 à 9 p.cent) durant les deux premières années de l'étude, mais a augmenté jusqu'á 13 à 20 p.cent au début de la période d'eau libre printanière de 1998, quand les chasseurs devaient tirer au-dessus de l'eau libre plutôt qu'au-dessus de la glace de rive. En s'appuyant sur ces estimations et sur les données de prélèvements renfermées dans l'étude sur la récolte des Inuvialuit, on a établi que les chasseurs d'Holman avaient prélevé de 3,7 à 6,9 p.cent de la sous-population, de l'eider à tête grise et moins de 1 p.cent de l'eider à duvet au cours des trois années constituant la période d'étude. Il semble que le niveau de récolte actuel de l'eider s'offrant aux chasseurs d'Holman soit viable, mais pour le confirmer, on a besoin d'un supplément d'information sur la mortalité naturelle et les taux de recrutement, en particulier dans le cas de l'eider à tête grise.eider à tête grise; Somateria spectabilis; eider à duvet; Somateria mollissima v-nigra; récolte; pertes dues aux blessures; migratio

Status of Marine Birds of the Southeastern Beaufort Sea

This summary and update of information on the marine birds of the southeastern Beaufort Sea is intended to support discussions on how to improve management of marine resources in the Canadian Beaufort Sea region. Perhaps the most outstanding use of the Beaufort Sea by marine birds is the staging during spring migration by hundreds of thousands of eiders and long-tailed ducks in the early open water off Cape Bathurst and Banks Island. During midsummer, tens of thousands of long-tailed ducks, scoters, scaup, and mergansers moult in the sheltered bays and behind barrier beaches and spits. Although several species of geese, ducks, loons, gulls, and terns nest on islands and in wetlands along the Beaufort Sea coast, this region has relatively few nesting seabirds compared to eastern Arctic Canada and the Bering Sea. Two possible reasons for this are a shortage of cliffs suitable for nesting and a lack of pelagic fish. The five most common sea duck species that occur in the region, long-tailed duck, king eider, common eider, surf scoter, and white-winged scoter, have all declined in numbers since the mid-1970s. Western Arctic brant populations have also declined, although their status within the Beaufort Sea region is unclear. Brant and king eider are the only marine bird species harvested there in substantial numbers. Other threats to Beaufort Sea marine bird populations include oil spills, global warming, coastal development, and contaminants. Certain threats can be managed at a local level since they are a result of local economic development, but others, such as global warming or loss of critical wintering areas, stem from environmental problems outside the region. Solving these issues will require mutual understanding and commitment on the part of numerous countries.Cette récapitulation et mise à jour de l'information sur les oiseaux marins du sud-est de la mer de Beaufort ont été faites dans le but de fournir des arguments sur la façon d'améliorer la gestion des ressources marines dans la zone canadienne de la mer de Beaufort. L'utilisation la plus notable que font les oiseaux marins de la mer de Beaufort est peut-être en tant que halte durant la migration printanière de centaines de milliers d'eiders et de canards à longue queue dans les premières eaux libres au large du cap Bathurst et de l'île Banks. Au milieu de l'été, des dizaines de milliers de canards à longue queue, de macreuses, de fuligules milouinans et de harles muent dans les baies abritées et en arrière des flèches et cordons littoraux. Même si plusieurs espèces d'oies, de canards, de huarts, de mouettes et de sternes nichent sur les îles et dans les zones humides longeant le rivage de la mer de Beaufort, cette région voit relativement peu d'oiseaux marins qui viennent y nicher en comparaison de l'est du Canada arctique et de la mer de Béring. Il y a deux raisons possibles à cet état de choses: trop peu de falaises propices à l'établissement de nids et un manque de poissons pélagiques. Les cinq espèces de canards de mer les plus courantes dans la région, à savoir, le canard à longue queue, l'eider à tête grise, l'eider à duvet, la macreuse à front blanc et la macreuse brune, ont toutes vu leurs nombres décliner depuis le milieu des années 1970. La population de bernaches cravants de l'ouest de l'Arctique est également en déclin, bien que le statut de cet oiseau au sein de la région de la mer de Beaufort ne soit pas évident. La bernache cravant et l'eider à tête grise sont les seules espèces d'oiseaux marins prélevées en nombre important à cet endroit. Parmi les autres facteurs qui menacent les populations d'oiseaux marins de la mer de Beaufort, on compte les déversements d'hydrocarbures, le réchauffement climatique, l'aménagement du littoral et les contaminants. Certaines menaces peuvent être gérées au niveau local vu qu'elles résultent du développement économique local, mais d'autres comme le réchauffement climatique ou la perte d'aires d'hivernage critiques sont issues d'enjeux environnementaux extérieurs à la région. La résolution de ces problèmes passe obligatoirement par une compréhension et un engagement mutuels de la part de nombreux pays

A Common Eider × King Eider Hybrid Captured on the Kent Peninsula, Nunavut

On 25 June 2002, we captured and recorded measurements of a male common eider (Somateria mollissima) × king eider (S. spectabilis) hybrid at Nauyak Lake, on the Kent Peninsula, Nunavut. This is the first documented capture of a hybrid eider, rarely observed in North America. Structural body measurements and mass of the hybrid were intermediate compared to those of Pacific common eiders (S. m. v-nigrum) at the same study site and king eiders at a nearby study site during the same time of year. The plumage of the captured hybrid had characteristics of both parent species. Mate pairing on overlapping spring staging or wintering areas of common and king eiders may occasionally result in hybrid offspring.Le 25 juin 2002, nous avons capturé un hybride composé d’un eider à duvet (Somateria mollissima) × un eider à tête grise (S. spectabilis) au lac Nauyak, dans la péninsule de Kent, au Nunavut, puis nous avons pris note de ses mesures. Il s’agit de la première capture répertoriée d’un eider hybride, ce qui est rarement observé en Amérique du Nord. Les mesures et la masse de la structure corporelle de l’hybride étaient intermédiaires comparativement à celles des eiders à duvet du Pacifique (S. m. v-nigrum) du même lieu d’étude et à celles des eiders à tête grise d’un lieu d’étude avoisinant pendant la même période de l’année. Le plumage de l’hybride que nous avons capturé présentait des caractéristiques des deux espèces. Il arrive parfois que les accouplements aux haltes migratoires du printemps ou aux aires d’hivernage partagées par les eiders à duvet et les eiders à tête grise donnent lieu à une progéniture hybride

Consistent Association of Type 2 Diabetes Risk Variants Found in Europeans in Diverse Racial and Ethnic Groups

It has been recently hypothesized that many of the signals detected in genome-wide association studies (GWAS) to T2D and other diseases, despite being observed to common variants, might in fact result from causal mutations that are rare. One prediction of this hypothesis is that the allelic associations should be population-specific, as the causal mutations arose after the migrations that established different populations around the world. We selected 19 common variants found to be reproducibly associated to T2D risk in European populations and studied them in a large multiethnic case-control study (6,142 cases and 7,403 controls) among men and women from 5 racial/ethnic groups (European Americans, African Americans, Latinos, Japanese Americans, and Native Hawaiians). In analysis pooled across ethnic groups, the allelic associations were in the same direction as the original report for all 19 variants, and 14 of the 19 were significantly associated with risk. In summing the number of risk alleles for each individual, the per-allele associations were highly statistically significant (P<10−4) and similar in all populations (odds ratios 1.09–1.12) except in Japanese Americans the estimated effect per allele was larger than in the other populations (1.20; Phet = 3.8×10−4). We did not observe ethnic differences in the distribution of risk that would explain the increased prevalence of type 2 diabetes in these groups as compared to European Americans. The consistency of allelic associations in diverse racial/ethnic groups is not predicted under the hypothesis of Goldstein regarding “synthetic associations” of rare mutations in T2D

Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial

Background Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy

Multiple novel prostate cancer susceptibility signals identified by fine-mapping of known risk loci among Europeans

Genome-wide association studies (GWAS) have identified numerous common prostate cancer (PrCa) susceptibility loci. We have fine-mapped 64 GWAS regions known at the conclusion of the iCOGS study using large-scale genotyping and imputation in 25 723 PrCa cases and 26 274 controls of European ancestry. We detected evidence for multiple independent signals at 16 regions, 12 of which contained additional newly identified significant associations. A single signal comprising a spectrum of correlated variation was observed at 39 regions; 35 of which are now described by a novel more significantly associated lead SNP, while the originally reported variant remained as the lead SNP only in 4 regions. We also confirmed two association signals in Europeans that had been previously reported only in East-Asian GWAS. Based on statistical evidence and linkage disequilibrium (LD) structure, we have curated and narrowed down the list of the most likely candidate causal variants for each region. Functional annotation using data from ENCODE filtered for PrCa cell lines and eQTL analysis demonstrated significant enrichment for overlap with bio-features within this set. By incorporating the novel risk variants identified here alongside the refined data for existing association signals, we estimate that these loci now explain ∼38.9% of the familial relative risk of PrCa, an 8.9% improvement over the previously reported GWAS tag SNPs. This suggests that a significant fraction of the heritability of PrCa may have been hidden during the discovery phase of GWAS, in particular due to the presence of multiple independent signals within the same regio

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Effects of fluoxetine on functional outcomes after acute stroke (FOCUS): a pragmatic, double-blind, randomised, controlled trial

Background Results of small trials indicate that fluoxetine might improve functional outcomes after stroke. The FOCUS trial aimed to provide a precise estimate of these effects. Methods FOCUS was a pragmatic, multicentre, parallel group, double-blind, randomised, placebo-controlled trial done at 103 hospitals in the UK. Patients were eligible if they were aged 18 years or older, had a clinical stroke diagnosis, were enrolled and randomly assigned between 2 days and 15 days after onset, and had focal neurological deficits. Patients were randomly allocated fluoxetine 20 mg or matching placebo orally once daily for 6 months via a web-based system by use of a minimisation algorithm. The primary outcome was functional status, measured with the modified Rankin Scale (mRS), at 6 months. Patients, carers, health-care staff, and the trial team were masked to treatment allocation. Functional status was assessed at 6 months and 12 months after randomisation. Patients were analysed according to their treatment allocation. This trial is registered with the ISRCTN registry, number ISRCTN83290762. Findings Between Sept 10, 2012, and March 31, 2017, 3127 patients were recruited. 1564 patients were allocated fluoxetine and 1563 allocated placebo. mRS data at 6 months were available for 1553 (99·3%) patients in each treatment group. The distribution across mRS categories at 6 months was similar in the fluoxetine and placebo groups (common odds ratio adjusted for minimisation variables 0·951 [95% CI 0·839–1·079]; p=0·439). Patients allocated fluoxetine were less likely than those allocated placebo to develop new depression by 6 months (210 [13·43%] patients vs 269 [17·21%]; difference 3·78% [95% CI 1·26–6·30]; p=0·0033), but they had more bone fractures (45 [2·88%] vs 23 [1·47%]; difference 1·41% [95% CI 0·38–2·43]; p=0·0070). There were no significant differences in any other event at 6 or 12 months. Interpretation Fluoxetine 20 mg given daily for 6 months after acute stroke does not seem to improve functional outcomes. Although the treatment reduced the occurrence of depression, it increased the frequency of bone fractures. These results do not support the routine use of fluoxetine either for the prevention of post-stroke depression or to promote recovery of function. Funding UK Stroke Association and NIHR Health Technology Assessment Programme