Breeding success of Northern Rockhopper Penguins (Eudyptes moseleyi) at Gough Island, South Atlantic Ocean

Abstract

Populations of Northern Rockhopper Penguins (Eudyptes moseleyi) are declining, and their breeding success is low compared with that of other species of Eudyptes. We tracked loss of broods and investigated how the response to threats by breeding birds and the density of nests in a colony influence breeding success of Northern Rockhopper Penguins on Gough Island. Brood loss was greatest (33–61%) during incubation and the early chick stage. Most (71%) hatchlings survived to form crèches, and 73% of chicks present during early crèche formation moulted into juvenile plumage. Breeding success was significantly positively correlated with the response to threats by breeding birds and the number of other breeding birds within a 1.5-m radius, a relationship that may be increasingly important in a declining penguin population.