1. School of Biological and Biomedical Sciences; Durham University; Durham DH1 3LE UK
2. Birds & Environmental Change Partnership; Climate Change and BioAdaptation Division; South African National Biodiversity Institute; Kirstenbosch Research Centre; P/Bag X7, Claremont 7735 Cape Town South Africa
3. Centre for Statistics in Ecology; Environment and Conservation, and University of Cape Town; Rondebosch 7701 Cape Town South Africa
4. Percy FitzPatrick Institute of African Ornithology; DST/NRF Centre of Excellence; University of Cape Town; Rondebosch 7701 Cape Town South Africa
5. RSPB Centre for Conservation Science; RSPB; The Lodge; Sandy Bedfordshire SG19 2DL UK
6. Animal Demography Unit; Department of Biological Sciences; University of Cape Town; Rondebosch 7701 Cape Town South Africa
7. Conservation Science Group; Department of Zoology; University of Cambridge; Downing Street Cambridge CB2 3EJ UK