Abstract

MONTEIRO, Milena Santos; SOUTO, Antonio  and  NASCIMENTO, Lídio França do. Comparações entre os comportamentos de forrageio nas diferentes faixas etárias do boto-cinza (Sotalia guianensis) (Cetacea; delphinidae) na Baia dos Golfinhos, Praia de Pipa - RN - Brasil. Rev. etol. [online]. 2006, vol.8, n.1, pp.13-25. ISSN 1517-2805.

The term 'forage' refers to the group of behaviours performed by dolphins in an attempt to obtain prey items. This study aims to describe and compare forage behavioral patterns of the gray dolphin in different age ranges. The animals were monitored from an observation point on a cliff at the Pipa Ecological Sanctuary, RN, using the ad libitum method (Altmann, 1974). The age ranges were categorized in adult, juvenile and infants. The bay was divided in nine areas and the day in two parts: morning and afternoon. Twenty-one forage behaviours were described, including chase, catch with or without leaps, group strategies and prey cast. There were no significant differences between the strategies (with or without leaps) performed by the adults and the juveniles. Adult dolphins got involved in fishing activities more intensely and were more successful in capturing preys than juveniles, while infants did not participate actively in fishing.

Keywords : Feeding; Forage strategies; Prey capture; Age range; Sotalia guianensis.

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