1. Edgerton Research Laboratory, New England Aquarium, Boston, MA 02110-3399, USA.
2. Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543-1049, USA.
3. Cornell Laboratory of Ornithology, Cornell University, Ithaca, NY 14850-1923, USA.
4. Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara, CA 93106-9610, USA.
5. Graduate School of Oceanography, University of Rhode Island, Narragansett, RI 02882-1197, USA.
6. Provincetown Center for Coastal Studies, Provincetown, MA, 02657-1911, USA.
7. Biological Sciences, University of North Carolina Wilmington, Wilmington, NC 28403-3201, USA.
8. Oceanography Department, Florida State University, Tallahassee, FL 32306-4320, USA.
9. Marine Laboratory, Duke University, Beaufort, NC 28516-8648, USA.