Contaminants and sea ducks in Alaska and the circumpolar region

Environmental Health Perspectives
Abstract has subscript/superscript to be fixed
By: , and 

Links

Abstract

We review nesting sea duck population declines in Alaska during recent decades and explore the possibility that contaminants may be implicated. Aerial surveys of the surf scoter (Melanitta perspicillata), white-winged scoter (M. fusca), black scoter (M. nigra), oldsquaw (Clangula hyemalis), spectacled eider (Somateria fischeri), and Steller's eider (Polysticta stelleri) show long-term breeding population declines, especially the latter three species. The spectacled eider was recently classified threatened under the Endangered Species Act. In addition, three other diving ducks, which commonly winter in coastal areas, have declined from unknown causes. Large die-offs of all three species of scoters during molt, a period of high energy demand, were documented in August 1990, 1991, and 1992 at coastal reefs in southeastern Alaska. There was no evidence of infectious diseases in those scoters. The die-offs may or may not be associated with the long-term declines. Many scoters had elevated renal concentrations of cadmium (high of 375 μg/g dry weight [dw]). Effects of cadmium in sea ducks are not well understood. Selenium concentrations in livers of nesting white-winged scoters were high; however, the eggs they laid contained less selenium than expected based on relationships for freshwater bird species. Histological evaluation found a high prevalence of hepatocellular vacuolation (49%), a degenerative change frequently associated with sublethal toxic insult. Cadmium and selenium mean liver concentrations were generally higher in those birds with more severe vacuolation; however, relationships were not statistically significant. We do not know if sea duck population declines are related to metals or other contaminants.

Study Area

Publication type Article
Publication Subtype Journal Article
Title Contaminants and sea ducks in Alaska and the circumpolar region
Series title Environmental Health Perspectives
DOI 10.2307/3432411
Volume 103
Issue 4
Year Published 1995
Language English
Contributing office(s) National Wildlife Health Center
Description 10 p.
Larger Work Type Article
Larger Work Subtype Journal Article
Larger Work Title Environmental Health Perspectives
First page 41
Last page 49
Country United States
State Alaska
Google Analytic Metrics Metrics page
Additional publication details