Patterns of immigration to and emigration from breeding colonies by African penguins

Abstract

Of over 20 000 African penguins Spheniscus demersus that had been flipper-banded as chicks between 1978 and 1999, 2% of those re-sighted after fledging settled to breed at non-natal colonies. This represented 14% of the banded birds that were subsequently recorded breeding. Only one of these immigrants had previously been recorded breeding at its natal colony, the rest presumably being first-time breeders. The largest proportions of banded chicks that emigrated came from Dyer Island on the south coast of South Africa, all of which settled at colonies to the west or north. Penguins emigrating from Namibian breeding colonies either relocated to the Western Cape of South Africa or settled at colonies farther to the north in Namibia. Emigration and immigration of African penguins are thought to be driven by changes in the distribution and availability of their prey. Eight penguins that were banded in adult plumage were found to have attempted breeding at more than one locality. All were survivors of the Apollo Sea oil spill of 1994 and had been cleaned and released by the Southern African Foundation for the Conservation of Coastal Birds. This is thought to be the first documented evidence of attempted breeding by African penguins at more than one locality.