THE DECLINE OF MINK IN GEORGIA, NORTH-CAROLINA, AND SOUTH-CAROLINA - THE ROLE OF CONTAMINANTS

Since the 1960s, mink (Mustela vison) populations in Georgia, North Ca rolina, and South Carolina have declined, especially in the coastal pl ain. A prior study suggested that the decline may stem from environmen tal contaminants. Based on water quality data from each state, we iden tified 17 substances potentially related to the decline: aldrin, dield rin, endrin, DDD, DDE, DDT, PCBs, chlordane, alpha-BHC, toxaphene, dib enzofuran, copper, chromium, cadmium, lead, arsenic, and mercury. Mink livers were analyzed for PCB and organochlorine pesticides, and kidne ys and femurs were analyzed for metals. Reference sample concentration s from piedmont, mountain, and foothill locations were compared to sta te coastal plain totals and counties. PCBs for Georgia, dieldrin for S outh Carolina, and endrin and aldrin for North Carolina were significa ntly higher than the piedmont reference group. Liver PCB concentration s were higher than those known to cause mink reproductive dysfunction. Mercury concentrations were significantly higher in coastal plain min k from all three states and were in the range of those known to cause impacts to reproduction, growth, and behavior to wild mink. it is unkn own what concentrations of cyclodienes cause reduced reproduction or o ther physiological effects in mink, but the levels reported here proba bly indicate background concentrations that do not contribute to the d ecline.