Philopatry In Nesting Adult Female Spectacled Eiders At Kigigak Island, Yukon Delta National Wildlife Refuge, Alaska

Moran, Tina L.

In response to the dramatic decline of the species (early 1970's to 1990's) on the Yukon-Kuskokwim Delta, I conducted a nesting ecology study on spectacled eiders (Somateria fischeri) at Kigigak Island from 1992-1996. The Kigigak Island population has had relatively high nest success between 1992-1996 (92%, 63%, 70%, 64%, and 82%, respectively). More than 50% of the nesting females have been marked (n=161). Preliminary results show that 70% of the marked females have returned to nest at least once following their banding year and that 52% returned at least two consecutive years. The spectacled eider estimate on Kigigak is relatively high compared with return rates reported for other duck species, including buffleheads (Bucephala albeola)( 44-50%) and mallards (Anas platyrhynchos) (40-46%). Preliminary results also show that returning females move an average of 200 m from previously used nest sites. I am currently examining relationships between partial predation, clutch size, nesting chronology and distances moved between individual female's nest sites.