In order to determine the role of contaminants in declining populations of seaducks, it is proposed that: (1) archived samples of Oldsquaw collected from their Canadian arctic breeding grounds be analyzed for Hg, Se and Cu (in liver), Cd (in kidney), Pb (in wing bone), and selected samples be screened for a wider range of metals (in liver), and (2) archived samples of Oldsquaw wing bone be analyzed for stable isotopes (13C/12C; 15N/14N, and 34S/32S) and strontium (Sr) to discriminate whether birds from certain geographical areas of the Arctic are overwintering in freshwater (i.e. Great Lakes) or marine environments.