1. Departments of Entomology and Fisheries and Wildlife, Michigan State University, East Lansing, Michigan 48824 USA
2. California Cooperative Fishery Research Unit, Humboldt State University, Arcata, California 95521 USA
3. Department of Biology, Loyola University of Chicago, Chicago, Illinois 60626 USA
4. Department of Biology, Colgate University, Hamilton, New York 13346 USA
5. US Fish and Wildlife Service, Chesapeake Bay Field Office, 177 Admiral Cochrane Dr., Annapolis, Maryland 21401 USA
6. Department of Entomology, Michigan State University, East Lansing, Michigan 48824 USA