Diet of the atlantic petrel Pterodroma incerta during the non-breeding season

Abstract

The Atlantic Petrel Pterodroma incerta breeds during the austral winter and mainly on Gough Island, remaining near the colonies during the breeding season and wintering on the South Atlantic Subtropical Convergence waters. Until now, all information about the diet of this species has been obtained during the breeding season, but these birds may take different prey items on the breeding grounds vs. the wintering grounds. We examined the stomach contents of 61 Atlantic Petrels stranded during the wintering season. A total of 1.183 food items were recorded, mainly cephalopods (93.9 %) and fish (6.1 %). Anthropogenic objects (i.e., debris) were found in 23 birds (37.7 %). Cephalopods are the main prey during both the breeding and the non-breeding seasons. The ingestion of debris by more than one-third of individuals is noteworthy and reveals an additional threat to this endangered species.