1. Department of Biology University of Victoria 3800 Finnerty Road Victoria British Columbia V8P 5C2 Canada
2. Hakai Institute P.O. Box 309 Heriot Bay British Columbia V0P 1H0 Canada
3. Stock Assessment and Research Division Pacific Biological Station Fisheries and Oceans Canada 3190 Hammond Bay Road Nanaimo British Columbia V9T 6N7 Canada