Realm: Marine
Climate: Polar
Biome: Large river delta ecosystems
Central latitude: 61.110000
Central longitude: -165.170000
Duration: 26 years, from 1988 to 2013

364 records

14 distinct species

Across the time series Anser albifrons is the most frequently occurring species

Methods

Data managers note: accounting for plot size anomalies resulted in transforming counts to densities in individuals per sq km. During the first years of the survey, randomly located plots were selected in the region. Since 2000, plots were selected within a consistent area of 716 km2, referred as the "core nesting area" and containing the majority of spectacled eider pairs. Estimates of nest population size for the period 1985-2013 were based on data collected on plots within the core nesting area corrected by nest detection rate. Selection of plots excluded plots sampled in the current or previous yeas. Plot size in most years was 0.324 km2. Two to four biologists searched each plot fo rup to 8 hours looking for active and destroyed waterfowl, crane, loon, and gull nets. Species were identified by visual confirmation of an adult at the nest or by comparing feathers in the nest with a photographic field guide. Loon nests are almost impossible to distinguish an dadults rarely remain near their nests, so the proportion of each species was calculated based on aerial observations. Each year we used Geographic Information Systems (GIS) and custom-written True BASIC computer programs to randomly select 85 plots within the core nesting area (Fig. 1). Selection of plot locations was restricted by excluding points that were sampled in the current or previous five years. Plot size in most years (1988-1994 and 1997-2013) was 402 m by 805 m (0.324 km2). Plot sizes were variable in 1985-1987 (0.16-1.66 km2), and were 0.45 km2 in 1995, and 0.36 km2 in 1996.

Citation(s)

@techreport{BioTIME_cit488, Study_id = {719}, Citation_id = {488}, Author = {Fischer, J.B. and Stehn, R.A}, Institution = {U.S. Fish and Wildlife Service}, Title = {Nest population size and potential production of geese and spectacled eiders on the yukon-Kuskokwim Delta, Alaska, 1985-2013}, Year = {2014}, Url = {https://www.researchgate.net/profile/Julian-Fischer-3/publication/268803421_Nest_population_size_and_potential_production_of_geese_and_spectacled_eiders_on_the_Yukon-Kuskokwim_Delta_Alaska_1985-2013/links/54b481d10cf2318f0f96df03/Nest-population-size-and-potential-production-of-geese-and-spectacled-eiders-on-the-Yukon-Kuskokwim-Delta-Alaska-1985-2013.pdf}, Language = {English} }