Waterfowl

Reports

Yukon Delta Nesting Waterfowl Survey

Annual assessment of nesting populations of geese on the Yukon-Kuskokwim Delta (YKD) provides information for biologists, participants in cooperative goose management plans, and Pacific Flyway technical committees. A ground-based sampling procedure has been used since 1986 to estimate the number of total nests, active nests, and eggs for cackling geese, emperor geese, greater white-fronted geese, and spectacled eiders. Annual information on the size of the nesting population and potential number of young produced contributes long term data needed to understand goose and eider population ecology and better manage these species.

Biologists searched for nests on randomly selected rectangular plots (about 400m x 800m) on a survey area of the central coastal zone of the Yukon Delta National Wildlife Refuge. All sites dry enough for a nest, particularly lake shores and islands, were examined for all active and destroyed goose, brant, eider, swan, crane, loon and gull nests. Nests of other species were recorded when encountered but most shorebird, passerine, and duck nests were missed.

They recorded species, nest site, number of eggs, evidence of predation, and other pertinent data on a standardized nest card for each nest. A few eggs in many clutches were floated to determine the approximate stage of incubation. The estimated total number of nests on the survey area was calculated to provide an estimate of the breeding population size. The estimated total number of viable eggs measured the number of young that could potentially augment the fall population. Information on nesting chronology was also calculated.

Click on the link below to view the 2008 field report.

Nest Population Size and Production of Geese and Spectacled Eiders Nesting on the Yukon -Kuskokwim Delta, Alaska in 2008 (pdf - 954kb)

An analysis of the impact of investigator disturbance on spectacled eiders and cackling geese associated with nest searching was conducted in 2003. Click on the following link to view the report:

Bowman, T.D. and R. A. Stehn. 2003. Impact of Investigator Disturbance on Spectacled Eiders and Cackling Canada Geese nesting on the Yukon-Kuskokwim Delta. Unpub. Rept. U.S. Fish and Wildlife Service, Anchorage Alaska 22p. (pdf)

Last Updated: October 2, 2008