Behaviour analysis of the loggerhead sea turtle Caretta caretta from direct in-water observation

Abstract

Direct observation of animal behaviour is essential for the effective conservation of endangered species in their natural habitat, understanding their function within ecosystems and val- idating inferences made using remote technology. The aim of this study was to document the daytime behavioural activity of loggerhead sea turtles Caretta caretta at a temperate breeding area through direct observations. Between April and July of 2003 to 2005, turtle behaviour on initial sighting was recorded during 287 h of observation, comprising 1534 sighting events of solitary (n = 80 male, n = 1335 female) and social (n = 65 same sex, n = 54 mixed sex) activity. We grouped observed activities into 4 solitary and 2 social behaviours, which were divided into 14 sub-categories. Solitary behaviour included resting, swimming, foraging and cleaning. Social behaviour included antagonistic interac- tions and reproductive activity. Foraging, cleaning and female–female contests are not documented in published literature for loggerhead sea turtles at breeding areas. Our results suggest that during the breeding period (1) male behaviour was primarily social and active (2) female behaviour was primarily solitary and inactive.