TROPHIC SPECTRUM OF THE NEOTROPIC CORMORANT (PHALACROCORAX BRASILIANUS) IN SAN MIGUEL DEL MONTE LAGOON

MONTALTI, DIEGO; GARBIN, LUCAS; FUCHS , DANIELA V.

CABA

Jornada; XVIII JORNADAS ANUALES MULTIDISCIPLINARIAS DE LA SAB; 2016

Sociedad Argentina de Biología

The Neotropic Cormorant Phalacrocorax brasilianus inhabits freshwater and marine environments from the Southern USA to the Horn Cape. It is an ichthyophagous species which shows a great ecological plasticity. We analyzed the Neotropic Cormorant diet at the San Miguel del Monte Lagoon, Buenos Aires province. We studied 24 stomach contents, identifying fish species through otoliths and bone remains. The 8 % of the stomachs were empty, and a total of 240 otoliths were found in the other 22 ones. The most frequent species was the Sabalito Cyphocharax voga present in 67 % of stomachs followed by the Vieja del agua Hypostomus commersoni and the Mojarra Astyanax eigenmanniorum. We also found other 9 species with representatives of other 5 orders (Clupeiformes, Siluriformes, Atheriniformes, Cyprinodontiformes, and Perciformes). In an ichthyological survey carried out in this lagoon the most represented species was C. voga. This results show that Neotropic Cormorant forage on fish species that are most abundant in Del Monte lagoon. Our study shows the large trophic spectrum of the Neotropic Cormorant, and also shows that it does not prey significantly on fish species of commercial importance. The Mojarra A. eigenmaniorum, Madrecita Jenynsia multidentata, and Chanchita Australoheros facetus as Neotropic Cormorant prey items are mentioned for the first time.