No abstract

This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

No abstract

29African Penguin Spheniscus demersus numbers have declined steadily over three 30 generations, resulting in a loss of nearly 60% since of 1989. The breeding population reached 31 an historic low of ~20,850 pairs in 2019. We use count data and JARA, a generalized Bayesian 32 state-space tool for estimating extinction risk estimates under IUCN Red List Criterion A, to 33 assess the current status of the African penguin population at a global scale. We then 34 deconstruct the overall decline in time and space to identify the regional populations most in 35 need of urgent conservation action. The population in South Africa has declined at a faster 36 annual rate (−5.1%, highest posterior density interval, HPDI: −9.1 to −1.1%) than the 37 population in Namibia, which has remained relatively stable since 1989 (−0.1%, HPDI: −3.7 38 to +3.6%). And within South Africa, the most rapid rate of change has been seen in the 39 Western Cape colonies to the north of Cape Town, which have declined at nearly 10% per 40 annum over the last 20 years. The large declines in the Western Cape (particularly at Dassen 41 Island and Dyer Island), coupled with slower declines at colonies further east have resulted in 42 the Eastern Cape colonies containing ~50% of the South African penguin population in 2019, 43 as compared to ~27% in 1989. These changes have been coincident with changes in the 44 2 abundance and availability of the main prey of the African penguin and eastward 45 displacements of a number of other marine resources in South Africa. Our results highlight the 46 dynamic nature of the decline of the African penguin population in both space and time, and 47 identify clear regions in which urgent conservation action is required.