1. Research Centre for Ecological Change, Organismal and Evolutionary Biology Research Programme University of Helsinki Helsinki FI‐00014 Finland
2. FitzPatrick Institute of African Ornithology, DST‐NRF Centre of Excellence University of Cape Town Cape Town South Africa
3. Finnish Museum of Natural History University of Helsinki Helsinki FI‐00014 Finland
4. Department of Electrical and Electronic Engineering Imperial College London South Kensington Campus London SW7 2AZ UK
5. Vultures Namibia Swakopmund Namibia