Diet and prey consumption of Antarctic petrels Thalassoica antarctica at Svarthamaren, Dronning Maud Land and at sea outside the colony

The diet of the Antarctic petrel Thalassoica antarctica was studied during two years at Svarthamaren, an inland colony situated in Dronning Maud Land, Antarctica and in the pack-ice outside Svarthamaren. The analyses showed that the most important food (wet weight) at Svarthamaren was Crustaceans (68%), followed by fish (29%) and squid (3%), whereas individuals collected in the pack ice took mostly fish (95%), followed by Crustaceans (5%). The prey composition and length found in this study is comparable to what is found in other diet studies. Estimates of food consumption for birds breeding at Svarthamaren (c. 250,000 pairs) indicate that the take approximately 6,600 tons of Crustaceans, 2,600 tons of fish and 485 tons of squid during the breeding season. Furthermore, their annual consumption is estimated to 34,800 tons of Crustaceans, 13,800 tons of fish, and 2,600 tons of squid. Satellite telemetry studies indicate at Antarctic petrels from Svarthamaren may fly more than 3,000 km during one foraging trip and may thus, cover a huge ocean area.