Acknowledgements
We thank Robben Island Museum (RIM) for permission to carry out research on the island, accommodation, and ferry transport; in particular, Sabelo Madlala and Inga Sipuka supported the fieldwork. We thank our long-term collaborators at the Department of Forestry, Fisheries and the Environment, particularly Azwianewi Makhado. Sue Kuyper and our institutions provided logistical support. Peter McKinnon (Biomark) provided invaluable assistance as we set up the PIT project on African penguins. Lizanne van Eerden, Gavin Peterson, and Corlie Hugo collected and input data from Stony Point, and numerous students, volunteers, and collaborators have helped with penguin fieldwork at Robben Island through our Earthwatch Institute project there. Stuart Bearhop provided comments that improved an earlier draft of the manuscript. Research permits were granted by the Department of Forestry, Fisheries, and the Environment (RES2013/66, RES2014/114, RES2015/12, RES2015/93, RES2016/06, RES2016/78, RES2017/06, RES2017/09, RES2018/08, RES2018/39, RES2019/04, RES2019/50, RES2020/24, RES2020/91) and CapeNature (0056-AAA007-00094, 0056-AAA007-00120 and CN44-59-6559). All research methods were approved by the Animal Welfare and Ethical Review Body at the University of Bristol (UIN UB/14/007), by the Science Faculty Animal Ethics Committee at the University of Cape Town (2013/V10/RSREV1, A1/2014/2013/V10/RS, 2017/V12/Ludynia and 2020/2017/V23/KL and by the Cornwall Research Ethics Committee and the Animal Welfare and Ethical Review Board at the University of Exeter (2017/1594, 2018/2404 and eCORN001760). Funding was provided by the Association of Zoos and Aquariums (through their SAFE programme), the Bristol Zoological Society, the Department of Forestry, Fisheries, and the Environment, the Earthwatch Institute (http://earthwatch.org/), the Pew Charitable Trusts (through a Pew Fellows Program in Marine Conservation award to R.B.S.), the Leiden Conservation Foundation (through fellowships award to R.B.S. and L.J.W.), SANCCOB, and the San Diego Zoo Wildlife Alliance. The views expressed in this paper are those of the authors and do not necessarily reflect the views of The Pew Charitable Trusts or any other funder.