ECOLOGIA ALIMENTAR DOS ALBATROZES Thalassarche melanophris E T.chlororhynchos E DOS PETRÉIS Procellaria aequinoctialis E P.conspicillata NO SUL DO BRASIL.

by Colabuono, Fernanda Imperatrice

Diet of Thalassarche melanophris (n=56), T. chlororhynchos (n=26), Procellaria aequinoctialis (n=36) e P. conspicillata (n=7) were studied in southern Brazil by using birds collected on the beach of Rio Grande do Sul and from longline off southern Brazil, between 1994 and 2004. Cephalopod beaks, fish otoliths and eye lenses were dominant in the food contents of these birds. About 90% of food objects of petrels were in the gizzard, mainly cephalopods beaks, because are more resistant of digestion and can accumulate easier. Between the anthropogenic objects ingested by these birds, plastics were the most frequently (90%) and the most numerous (83,6%). Cephalopods dominated the diet of P.aequinoctialis (Frequency of occurrence (FO%) 75-100%, number contribution (Nr%) 77,3-94,8%) and P. conspicillata (FO% 85,7%; Nr% 95,9%), mainly squids of the familyHistioteuthidae, while the importance of fishes increased for the albatrosses (T. melanophris FO% 64-70%; Nr% 50,6-69,6% and T. chlororhynchos FO% 47,6-100%;Nr% 47,2-100%). Demersal fishes occurred in the diet of T. melanophris, T. chlororhynchos and P. aequinoctialis. In food contents of beached birds was found a higher number and diversity of fishes of continental shelf than in the diet of birds killed by longline, which had an increase in the importance of cephalopods. The cephalopods that compounded the diet of these birds are mainly by subantarctic and subtropical waters.Besides the birds feeding cephalopods available naturally in the environment, about 40% of total of fishes found in the food contents may be deriving from discards fisheries, which isevidence of a strong interaction of these birds with the fisheries in southern Brazil.