The spectacled eider (Somateria fischeri) is a threatened species, found in Alaska, that is undergoing serious population declines. Until recently, little has been know about it's natural history...
From the US Fish and Wildlife Service, Region 7, web page:
"Most of the world's threatened spectacled eiders (Somateria fischeri) fly to northern Russia to breed. Smaller portions of the world population fly to Alaska's Arctic Coastal Plain and Yukon-Kuskokwim Delta to nest. Although there is no population trend information for this species in Russia, traditional knowledge of Alaska North Slope Natives suggests that breeding populations of this species have declined notably on Alaska's Coastal Plain. Data from U.S. Fish and Wildlife Service spring waterfowl breeding surveys suggest a dramatic decline of over 90% on the Yukon-Kuskokwim Delta during the past forty years."
We participated in a recent study of contaminant levels and biomarker responses in spectacled eiders. Spearheaded by the U.S. Fish and Wildlife Service (through their Contaminants Specialist, and ex-graduate student, Kim Trust), a small sampling of eiders from St. Lawrence Island, Alaska, was collected and assessed for metal and organochlorine content as well as biomarker levels.
There were relatively low levels of organochlorine contaminants, consistent with unremarkable cytochrome p450 changes in the birds. Levels of renal and hepatic selenium and the heavy metals, cadmium and copper, were elevated, though porphyrin profiles were not significantly perturbed as a function of any single or multiple metal exposure. Metallothionein (MT) levels in the study birds were elevated sufficiently to buffer the cadmium present, though the presence of significantly elevated copper concentrations suggests that overall MT levels may have been insufficient to buffer the overall load of MT-binding metals. You can find the results of this study in:
Trust, K.A., K.T. Rummel, A.M. Scheuhammer, L.I. Brisbin, M.J. Hooper. 2000. Contaminant exposure and biomarker response in spectacled eiders (Somateria fischeri) from St. Lawrence Island, Alaska. Arch. Envtl. Contam. Tox. 38:107-113.
Spectacled eiders are particularly interesting in their dispersal patterns. Visit the US FWS Region 7 Spectacled Eider web page to get information on the massive wintering flocks that have recently been discovered in the Bering Sea. The flock pictured at left numbers over 5000 birds! Flocking behavior like this is interesting toxicologically, as large proportions of entire species populations can be found in a single location, making them particularly susceptable to stressors, chemical or otherwise, that may threaten them.
