Alaska Science Center
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Spectacled Eider Satellite Telemetry Research at the Alaska Science CenterSpectacled Eiders (Somateria fischeri) are large sea ducks that spend 9 to 12 months of the year in marine habitat (Petersen et al. 1999). At sea, eiders forage on clams, polychaete worms, and other organisms on the sea floor. In winter, the world population of Spectacled Eiders group at a single site south of St. Lawrence Island, Alaska, in the northern Bering Sea. In the summer, the species is divided into three breeding populations; western and northern Alaska and northern Russia. A majority (> 90%) of adults nest in Russia. From 1952 to 1993, a 96% population decline was observed within the western Alaska breeding population. In 1993, the Spectacled Eider was listed as threatened under the Endangered Species Act and critical habitat was later designated throughout the species’ North American range (Federal Register 1993, Federal Register 2001). Threats to eiders at breeding areas include ingestion of contaminants, particularly lead through expended shot and predators (Petersen et al. 2000). Unlike other sea ducks, the distribution of Spectacled Eiders appears to be restricted to a few areas, including a single wintering site. This phenomenon might be detrimental to a significant number of eiders if habitat change leads to rapid alteration of high use areas. Recent research has focused on habitat conditions at the known wintering area, south of St. Lawrence Island, where sea ice and abundant, nutrient rich prey appear to be critical for winter survival (Petersen and Douglas 2004, Lovvorn et al. 2009). Without further assessment of migratory patterns and habitat use exhibited by Spectacled Eiders, it is difficult to predict how this threatened species will respond to rapid climate and ecosystem change in the future.
Satellite telemetry provides a mechanism through which the location of marked animals can be tracked regardless of location, time of day, or weather. Transmitters send information to orbiting satellites, which relay the data to receivers on Earth. In 1993 -1997, biologists at the Alaska Science Center marked Spectacled Eiders with implantable satellite transmitters, which led to the discovery of critical molting and wintering areas (Petersen et al. 1999). However, technology at the time limited the life of each transmitter to a few months, meaning data from late winter and spring locations was not collected. In 2008, biologists at the Alaska Science Center began marking Spectacled Eiders with similar transmitters to repeat and expand upon the previous study. Each transmitter is expected to send data over the course of 2 years, providing a unique opportunity to learn more about this unique species. At least 100 transmitters will be deployed through 2010, providing location data from 2008 through 2012. The data will ultimately be used to examine migratory patterns and habitat use throughout the year. The map below illustrates the most recent location signals received from marked Spectacled Eiders. View locations over time from eiders marked in 2008 in western Alaska. View locations over time from eiders marked in 2009 in northern Alaska. Research updates are also available via Twitter at http://twitter.com/USGS_SpecEider. This project is also being conducted as a component of a graduate degree at the University of Alaska Fairbanks. In addition to USGS funding, this project is being supported by the Minerals Management Service, the U.S. Fish and Wildlife Service, the Bureau of Land Management, the National Fish and Wildlife Foundation, ConocoPhillips-Alaska, Inc., the Mesker Park Zoo (Indiana), and the Columbus Zoo (Ohio).
LiteratureFederal Register. 1993. Final rule to list the Spectacled Eider as threatened. Federal Register 58(88):27374-27480. (pdf file 2.58 mb) |