1. Wildlife, Fish and Conservation Biology, University of California Davis, One Shields Avenue, Davis, CA 95616, USA
2. Max Planck Institute, Schlossallee 2, 78315 Radolfzell, Germany
3. Hopkins Marine Station of Stanford University, 120 Oceanview Boulevard, Pacific Grove, CA 93950, USA
4. Monterey Bay Aquarium, 886 Cannery Row, Monterey, CA 93940, USA
5. Point Reyes National Seashore, Inverness, CA 94937, USA
6. Department of Ecology, Montana State University, PO Box 173460, Bozeman, MT 59717, USA