Seasonal Movements and Distribution of Steller’s Eiders (Polysticta stelleri) Wintering at Kodiak Island, Alaska

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.De 2004 à 2006, nous avons recouru à la télémétrie satellitaire pour décrire l’utilisation de l’habitat et les mouvements annuels d’un segment de la population d’eiders de Steller (Polysticta stelleri) dans la région du Pacifique, eiders qui hivernent sur l’île Kodiak, en Alaska. Il est essentiel d’obtenir des données sur les tendances à grande échelle de la répartition saisonnière et des liens entre les divers stades du cycle annuel de ces oiseaux afin d’être en mesure d’interpréter leurs tendances démographiques et d’élaborer des stratégies de conservation. Nous avons capturé des oiseaux dans la baie Chiniak de l’île Kodiak vers la fin février et le début mars. Après notre départ de l’île Kodiak, nous avons surveillé les mouvements de 24 oiseaux pistés par satellite : 16 femelles de plus de deux ans, une femelle de deux ans et sept mâles de plus de deux ans. Tous les oiseaux ont emprunté le même couloir de migration intercontinental au printemps, mais les routes et la chronologie de la migration printanière semblaient varier d’une année à l’autre et d’un individu à l’autre. Seize des24 oiseaux pistés ont migré vers des aires de reproduction situées le long de la côte arctique de la Russie, depuis la presqu’île de Tchoukotkae jusqu’à la presqu’île de Taïmyr; cinq oiseaux, probablement non reproducteurs, ont passé l’été dans les eaux côtières de la Russie et de l’Alaska, tandis que les trois autres oiseaux sont morts pendant la migration printanière ou étaient dotés de transmetteurs défectueux. Treize oiseaux ont été repérés à des sites de mue largement répartis le long de la côte de l’Alaska. Parmi ces sites, notons ceux de l’île Saint-Laurent, du haut-fond de Kuskokwim, de la baie de Kamishak et de trois autres sites le long de la péninsule de l’Alaska. Douze de ces 13 oiseaux sont retournés à l’île Kodiak pour passer l’hiver, et un seul mâle a hiverné dans la péninsule de l’Alaska. Les eiders de Steller qui ont été marqués à l’île Kodiak pendant l’hiver étaient largement répartis pendant la saison de reproduction, mais une grande proportion d’oiseaux pistés sont retournés aux aires de mue et d’hivernage au cours des deux années visées par l’étude

MIGRATION CHRONOLOGY, ROUTES, AND DISTRIBUTION OF PACIFIC FLYWAY POPULATION LESSER SANDHILL CRANES

Managers of migratory game birds require accurate information about bird movements to delineate populations, protect important habitats, and regulate harvest. Data describing movements of sandhill cranes (Grus canadensis) belonging to the Pacific Flyway Population (PFP) are lacking. We used satellite telemetry to monitor movements of PFP lesser sandhill cranes (Grus c. canadensis) captured in the upper Cook Inlet and Bristol Bay regions of Alaska. Satellite transmitters were deployed on 19 flightless young (colts) and 3 adults over 3-years (2000-2002). Chronology, routes, and stopover or staging areas were identified for fall and spring migration periods. On average, cranes (n = 11) took 27 days (range = 13-44 days) to travel from summer areas in Alaska to winter areas in the Central Valley of California (CVC). Winter locations were concentrated in the Sacramento – San Joaquin River Delta and the East Grasslands (Merced County) regions. In spring, cranes (n = 10) took an average of 58 days (range = 45-65 days) to return to Alaska. In spring, most marked cranes (70%) staged at the Potholes Reservoir region in central Washington. PFP cranes that summer in Cook Inlet and Bristol Bay used identical migration routes and winter areas. Only 3 of 9 colts returning to Alaska, as juveniles, revisited their natal site. We found no evidence that PFP cranes monitored with satellite transmitters mixed with cranes from the Mid-Continent Population (MCP) or with “western segment” PFP cranes

Nesting ecology of ducks in interior Alaska

Thesis (M.S.) University of Alaska Fairbanks, 1994This study represents one of the first intensive efforts to locate and monitor duck nests in interior Alaska. We located 263, 409 and 450 nests of 12 duck species on Minto Flats in 1989, 1990 and 1991,respectively. We conclude that habitat for breeding waterfowl cannot be considered stable in interior Alaska. Flooding reduced the availability of meadows which precluded ducks from nesting in high-water years despite their presence during the Breeding Pair Survey. Differences in the length of the breeding season and differential response to photoperiod between sub-Arctic and prairie nesting ducks suggest the potential for genetic differences between populations. Similar clutch sizes between high and mid-latitudes, however, suggest that ducks are able to compensate for the additional energetic costs associated with breeding at high latitudes. Flooding of meadow habitat and low nest success resulting from predation probably limit overall duck production on Minto Flats