Mercury concentrations in post-fledging Wood Storks

Mercury concentrations were measured in blood, down and feather samples col lected front 20 postfledging Wood Storks (Mycteria americana) captured in t he coastal zone of Georgia to establish a reference level for free-ranging storks utilizing this region and assess if mercury is present in potentiall y hazardous concentrations. Blood concentrations ranged froth 0.04-1.57 mug Hg/g (wet weight) and down and feather concentrations ranged from 1.23-18. 05 mug Hg/g (dry weight). Comparisons of observed concentrations with publi shed levels of concern suggest that some free-ranging storks may be at risk of sublethal effects due to mercury contamination. Observed concentrations are generally higher than those reported for Wood Stork nestlings in this region from the same time period, possible resulting from differences in di et and patterns of down/feather growth and molt.