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

Author(s): 
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.