1. Conservation Science Group; Department of Zoology; University of Cambridge; Downing Street Cambridge CB2 3EJ UK
2. RSPB Centre for Conservation Science; Royal Society for the Protection of Birds; The Lodge Sandy SG19 2DL UK
3. Department of Conservation Biology; Estación Biológica de Doñana - CSIC; Avenida de Américo Vespucio s/n Seville E-41092 Spain
4. Department of Applied Biology; Universidad Miguel Hernández; Ctra Beniel km 3·2 Alicante E-03312 Spain
5. Faculty of Life Sciences and Engineering; University of Lleida; Lleida E-25003 Spain
6. Division of Conservation Biology; Institute of Ecology and Evolution; University of Bern; Bern 3012 Switzerland