1. FitzPatrick Institute of African Ornithology, DST/NRF Centre of Excellence, University of Cape Town, Cape Town, South Africa
2. Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences, Umeå, Sweden
3. Plant Conservation Unit, Department of Biological Sciences, University of Cape Town, Cape Town, South Africa
4. School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Johannesburg, South Africa