1. Department of Integrative Biology, University of Guelph, Guelph, ON N1G 2W1, Canada.
2. Department of Integrative Biology, Oregon State University, Corvallis, OR 97331, USA.
3. South Slough National Estuarine Research Reserve, P.O. Box 5417, Charleston, OR 97420, USA.
4. Oregon Institute of Marine Biology, P.O. Box 5389, Charleston, OR 97420, USA.