1. Ecosystem Research Center, Corson Hall, Cornell University, Ithaca, NY 14853, and Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543.
2. Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543.
3. BioSonics Incorporated, 4520 Union Bay Place NE, Seattle, WA 98105.
4. Harbor Branch Oceanographic Institution, 5600 Old Dixie Highway, Fort Pierce, FL 34946.