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     The spectacled eider (Somateria fischeri), a beautiful duck of Alaska and arctic Russia, has incurred great declines that may be related to ingestion of toxic chemicals.  The Iowa-sized Yukon-Yuskokwim Delta of western Alaska had 100,000 of these ducks breeding here in the 1970s, but beginning in 1986, they lost 14 percent of their population each year; 95 percent of their original numbers are now gone, leaving only about 5,000 birds (Dunkel 1997).  In 1993, the species was listed as threatened on the Endangered Species Act, and a task force set about trying to discover the causes.  They found that many of the birds had high levels of lead from Eskimo hunting with bird shot.  Although 34 of the 42 Eskimo villages in the delta have passed resolutions in favor of using steel shot over lead shot, most natives apparently believe that the birds are dying out from being studied and handled by biologists (Dunkel 1997).  One Fish and Wildlife Service biologist observed a spectacled eider dying of lead poisoning:  "She was flopping along [on the ground] and couldn't lift her head . . . She died within an hour" (Dunkel 1997).  Lead in sub-lethal concentrations can cause females to abandon nests and males to become infertile.  

      Lead poisoning has killed other wildlife as well. The magnificent and rare Steller's sea eagles of Russia's Kamchatka Peninsula and northern Japan have been dying of lead poisoning from eating carcasses of deer killed by Japanese hunters (Garcelon 1999).  Lead shot cannot be used by United States waterfowl hunters (other than native Americans) because of massive bird-kills in marshes where lead shot accumulated. 

     

     Until February 1995, the wintering area of spectacled eiders, where they spend 10 months of the year, was unknown.  The Fish and Wildlife Service had attached radio transmitters to several of these ducks, only to find the signals fading during the winter.  One radio, however, continued to send out signals which were detected and located by biologists flying over the Bering Sea in a small plane (Dunkel 1997).  To their amazement, they saw flotillas of these ducks, gathered in dense flocks south of St. Lawrence Island off western Alaska. Packed close together, their body heat helped keep the ice open.  DNA studies determined that these ducks comprised the entire world population of the spectacled eider, converged from Alaska's North Slope, the western Alaskan delta and arctic Russia.  Each returns to the location where it hatched, and when one population declines, there is no recruitment from the others (Dunkel 1997).  This makes the decline in the Yukon-Kuskokwim Delta population all the more serious.  The Bering Sea has been found to contain cadmium, selenium, strontium and other contaminants in high concentrations, which might be another explanation for the decline in these ducks (Dunkel 1997).  Their disappearance coincides with the downward population trends of Alaskan mammals that were abundant only a few decades ago.  Harbor seals of the Bering Sea have plummeted 60 percent since the 1970s; fur seals, 20 to 40 percent and Steller's sea lions (Eumetopias jubatus), a disastrous 80 percent, pushing them to endangered status (Dunkel 1997).  Overfishing may play a role in these declines, but since the spectacled eider feeds on mussels and other bivalves, as well as surface invertebrates, and has declined concurrently with the others, contaminants are apparently playing an important role.