1. S. C. Ludwig (http://orcid.org/0000-0003-3209-0568) (sludwig@gwct.org.uk), D. Baines, Game and Wildl
2. N. J. Aebischer, Game and Wildlife Conservation Trust, Burgate Manor, Fordingbridge, Hampshire, UK.
3. S. Roos, RSPB Centre for Conservation Science, RSPB Scotland, Edinburgh, UK.