1. Department of Wildlife, Fisheries, and Conservation Biology, 5755 Nutting Hall; University of Maine; Orono ME 04469 U.S.A.
2. School of Marine Sciences, 5706 Aubert Hall; University of Maine; Orono ME 04469 U.S.A.
3. U.S. Geological Survey, Maine Cooperative Fish and Wildlife Research Unit, 5755 Nutting Hall; University of Maine; Orono ME 04469 U.S.A.