Behaviour Patterns in Captive Manatees (<I>Trichechus manatus manatus</I>) at Itamaracá Island, Brazil

Abstract

Abstract The Antillean manatee ( Trichechus manatus mana-tus ) is distributed along much of the northern and eastern coasts of Brazil, although relatively little is known of the ecology or behaviour of the mem-bers of this population. In the present study, the behaviour of seven juvenile manatees earmarked for reintroduction to the wild was monitored using focal animal sampling over a 20-d period at the Aquatic Mammal Centre (CMA/ICMBIO) on Itamaraca Island, Pernambuco. The primary aim of this study was to characterise behaviour patterns, especially individual differences, as a baseline for monitoring during reintroduction. In particular, it was hoped that specific patterns could be identified as a diagnostic reference for the evaluation of an individual’s potential for suc-cessful reintroduction. Overall, while resting was the predominant activity of all but one subject, considerable individual variation was recorded in all behavioural categories. In addition, significant differences were recorded between morning and afternoon sessions, with some individuals pre-senting a given category during only one part of the day. Some of the behaviour patterns, such as circular movement, appeared to be related to anxi-ety or stress and might be useful for the behav-ioural diagnosis of individuals earmarked for re-introduction, although it will only be possible to interpret the exact implications following the re-introduction process. Key Words: Antillean manatee, Trichechus manatus manatus , behaviour, captivity, individual variation, reintroduction, Brazil