Análisis de la dieta invernal del cormorán grande (Phalacrocorax carbo sinensis) en dos embalses del norte de España: comparación de dos métodos de estudio

Resum

Analysis of cormorants (Phalacrocorax carbo sinensis) wintering food composition in two reservoirs in northern Spain: a comparison of two study methods
Wintering food of cormorants in two reservoirs in northern Spain was studied by direct field observations of feeding birds and analysis of pellets taken in night roosts. Direct observations revealed the length of captured fish and food composition. Pellet analysis allowed estimate only of the biomass intake. The estimate of daily food intake using the analysis of pellets was similar to that found during the breeding season in northern Europe. Data showed a differential predigestion between long and short prey (< 13 cm) with the associated loss of information when using pellet analysis.