1. FitzPatrick Institute of African Ornithology, Department of Biological Sciences, University of Cape Town, Cape Town, South Africa
2. Centre for Functional Biodiversity, School of Life Sciences, University of KwaZulu-Natal, Scottsville, South Africa
3. BirdLife South Africa, Isdell House, Johannesburg, South Africa
4. ICON Science, School of Global, Urban and Social Studies, RMIT University, Melbourne, Australia