Analysis of Lead and Arsenic Exposure in American Woodcock (Scolopax minor) from Michigan and Maine

Wing bones from 203 American Woodcock (Scolopax minor) harvested in Michigan, and 151 harvested in Maine, were analyzed for lead (Pb) levels. Concentrations greater than 20 µg/g were considered elevated (Scheuhammer et al., 1999). Four samples from Michigan and six from Maine with bone lead concentrations greater than 100 µg/g DW were removed from teh bone lead analysis and used to compare levels of Pb in bone to arsenic concentrations in feathers from corresponding wings of each bone sample. In Michigan, 72.9% of samples had elevated Pb levels. Adults had higher levels than juveniles (p=0.003), and females had higher levels than males (p<0.05). Bone-Pb levels were compared to background levels of Pb in Michigan soil, and to the number and effort (days afield) of hunters (using Pb shot) in Michigan's three hunting and trapping zones. Soil samples using glacial lobes as boundaries, showed the Western Upper Peninsula (U.P.) lobe had higher levels of background Pb than the Michigan lobe (p=0.04). Mean bone-Pb levels showed no significant difference among samples when grouped by lobe. Among Michigan's hunting and trapping zones, hunter numbers and effort were greater in the Northern Lower Peninsula (NLP) (p<0.001). When bone samples were grouped by geographic hunting zones, there was no significant difference in mean bone-Pb levels among zones. Mean bone-lead levels did not reflect use of lead shot by hunters when compared to Soil-Pb levels. In Maine, 84.1% of samples had elevated lead levels. Adult males had higher levels of lead than immature males (P<0.001), and adult females had higher lead concentrations than any other age-sex class (p<0.001). Between state comparisons for all age-sex classes indicate birds frome Maine had higher bone-lead levels than those in Michigan (p