Trace elements in lesser scaup (Aythya affinis) from the Mississippi flyway.

Previous research reported that concentrations of selenium in the livers of 88-95% of lesser scaup from locations in Lake Erie, Lake St. Clair, and Lake Michigan, USA were either elevated (10-33 microg/g dry weight [dw]) or in the potentially harmful range (> 33 microg/g dw). In order to determine the geographic extent of these high selenium concentrations, we collected lesser scaup in Louisiana, Arkansas, Illinois, Minnesota, Wisconsin, and Manitoba and analyzed the livers for 19 trace elements.