Bering Sea | Seabirds MASTER’S POSTER PRESENTATION Have forage conditions for molting Steller’s eiders ( Polysticta stelleri ) changed in Izembek Lagoon? Presenter: Annie Maliguine , ammaliguine@alaska.edu, University of Alaska Fairbanks Courtney Amundson , Courtney.Amundson@usda.gov, U.S. Dept. of Agriculture, Food Safety and Inspection Service Izembek Lagoon, located in the Alaskan southern Bering Sea, is designated as critical molting and wintering habitat for the Alaska-breeding population of Steller’s eiders ( Polysticta stelleri ), which is listed as Threatened under the United States Endangered Species Act. Izembek Lagoon is also an important stopover site for many other species of migratory water birds. Since the early 1980s, there has been a significant decline of Steller’s eiders in Izembek Lagoon compared to other historical molting sites (e.g., nearby Nelson Lagoon); the cause of this decline is unknown. In recent years, however, higher sea temperatures have been observed in Izembek Lagoon and warming ocean temperatures have been associated with shifts in benthic community structure elsewhere. In 2018 and 2019, we replicated a benthic sampling effort conducted by the U.S. Geological Survey in 1998 to understand if prey availability could be less favorable to support Steller’s eiders during their molt in Izembek Lagoon. Benthic grab samples were collected at 30 stations across Izembek Lagoon in areas where high concentrations of eiders were observed in 1998 and years prior. We compared forage conditions based on the relative biomass of marine benthic invertebrate groups between 2018/2019 to 1998. Preliminary results suggest a shift in benthic community composition. If forage conditions are less favorable, eiders may redistribute to other locations or the population at Izembek Lagoon may decline. This study provides a contemporary assessment of habitat conditions in a critical habitat for Steller’s eiders. Tuula Hollmen , tehollmen@alaska.edu, University of Alaska Fairbanks Brenda Konar , bhkonar@alaska.edu, University of Alaska Fairbanks
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