INVESTIGADORES
GARAFFO Griselda Valeria
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 sequential foraging behavior of
dusky dolphins (Lagenorhynchus obscurus). Foraging sequences were defined
when more than two feeding bouts occur with a traveling bout between them.
We hypothesized that traveling 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 understand 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 traveling and feeding in
the warm season (Kruskal-Wallis: H = 172.07, P < 0.01). 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 by 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.