DIETA DEL CHIMANGO (MILVAGO CHIMANGO) DURANTE EL PERIODO REPRODUCTIVO EN EL SUDESTE DE LA PROVINCIA DE BUENOS AIRES, ARGENTINA

LAURA MARINA BIONDI, MARIA SUSANA BO, MARCO FAVERO

ORNITOLOGIA NEOTROPICAL

The Neotropical Ornithological Society

Año: 2005 vol. 16 p. 31 - 42

1075-4377

Abstract. – Diet of the Chimango Caracara (Milvago chimango) during the breeding season in the southeastern Buenos Aires Province, Argentina. – The diet of the Chimango Caracara (Milvago Chimango) during the breeding season was studied by analyzing 150 pellets and 108 prey remains collected at roost and nest sites. Insects represented 96% of all prey items. Carrions, mainly fishes, birds and mammals, accounted for only 1% of the total number of prey, but made up 48% of total ingested biomass. Insects, amphibians, birds and mammals comprised 95% of the estimated biomass. In this sense, vertebrates dominated during the first months of the breeding season, whereas insects were more abundant towards the end, possibly due to a decrease in the vertebrate availability, and/or changes in the adult diet according to the nutritional requirements of nestlings. The changes in the vertebrate consumption and other prey according to their environmental availability indicate opportunistic hunting behavior by Chimango Caracara. This opportunism resulted in a lower niche breadth than that expected for a generalist species. Many of the prey of the Chimango Caracara are considered as crop pests and, therefore, play a beneficial role for humans.