IIMYC   23581
INSTITUTO DE INVESTIGACIONES MARINAS Y COSTERAS
Unidad Ejecutora - UE
artículos
Título:
Sequential foraging of dusky dolphins with an inspection of their prey distribution
Autor/es:
M DEGRATI ; SL DANS; GV GARAFFO; AG CABREIRA; F CASTRO MACHADO; EA CRESPO
Revista:
MARINE MAMMAL SCIENCE
Editorial:
WILEY-BLACKWELL PUBLISHING, INC
Referencias:
Lugar: Londres; Año: 2013 vol. 29 p. 691 - 704
ISSN:
0824-0469
Resumen:
The aim of this work was to analyze the foraging behavior of dusky dolphins (Lagenorhynchus obscurus). Foraging sequences were defined when more than two feeding bouts occurring with a travelling bout between them. We hypothesized that travelling costs of searching for prey patches were related to the time spent feeding on a patch. In addition, the distribution and seasonal variation of anchovy schools were studied in the area to better understood dolphins behavior. We observed dolphins from a research vessel from 2001 to 2007, and recorded their location and behavior. Anchovy data were collected during two hydro-acoustic surveys. Dusky dolphin behaviors varied seasonally, they spent a greater proportion of time travelling (U = 2763, P < 0.001) and feeding (U = 2695, P < 0.001) in the warm season. During the cold season dolphin groups were more likely to exhibit diving behavior and less surface feeding. We found a positive correlation between searching and foraging time (r = 0.88, P = 0.019), suggesting that the costs associated with searching were compensated for an increase in the energy intake during the foraging bout. There was an association between dusky dolphin and anchovy distribution, in that they co-varied spatially and seasonally.