Foraging ecology of Great Cormorants Phalacrocorax carbo sinensis during breeding in a recently colonized area (Ebro valley, Northern Spain)

Full article

Published:

Volume 49(2), December 2002. Pages 241-247.

Language:

Spanish

Original title:

Ecología trófica del Cormoran Phalacrocorax carbo sinensis durante la época reproductora en una zona de reciente colonización (valle del Ebro)

Keywords:

Breeding season, Cormorant, diet, foraging parameters, Navarre (northern Spain), Phalacrocorax carbo sinensis

Abstract:

Two breeding pairs of cormorants Phalacrocorax carbo sinensis started breeding in 1999 in a riparian wood in the ebro river (northern Spain). The diet and the main feeding parameters (foraging time, dive time and biomass intake) of this breeding population were studied during three consecutive breeding seasons (1999-2001). Barbels Barbus graellsii and soiffes Chondrostoma miegii were the most important prey species (Table 1). The average distance between the main feeding areas (Ebro and aragon rivers) and the nest sites was 3.8 km. No differences in diet were found between males and females (Table 1), although males captured larger fishes (FIG. 1) and more fish biomass than females per foraging bout. The time spent fishing and the average duration of divings were shorter in females than males. The larger body size of males could be the cause of these differences.