1. T. A. Porteus (http://orcid.org/0000-0003-0666-2593) (tporteus@gwct.org.uk), Dept of Zoology, Univ. of British Columbia, Vancouver, BC, Canada.
2. Present address and address for J. C. Reynolds, Game and Wildlife Conservation Trust, Burgate Manor, Fordingbridge, SP6 1EF, UK.
3. M. K. McAllister, Inst. for the Oceans and Fisheries, Univ. of British Columbia, Vancouver, BC, Canada.