ADDITIONAL DATA ON MERCURY ACCUMULATION IN NORTHERN MICHIGAN RIVER OTTERS

This study documented mercury contamination in river otter (Lutra cana densis) in the Keweenaw Bay area, northern Michigan. Total mercury con centrations in liver and kidney from 11 otters were determined by atom ic absorption spectroscopy and ranged from 0.79 to 4.07 mug g-1 wet we ight. There were no significant differences in mercury concentrations between males and females, or between tissue types. A significant diff erence did exist between mercury levels in mature animals and those in immature animals (<1 year old). Data indicate that otters in arcas wi th no known point sources are contaminated with mercury.