Ethnoecological aspects and implications for conservation of Tursiops truncatus (Cetartiodactyla: Delphinidae) in the Cagarras Archipelago, Rio de Janeiro, Brazil

The objectives of this study were to understand the ecological aspects of the common bottlenose dolphin ( Tursiops truncatus ) in the Cagarras Archipelago, Rio de Janeiro, Brazil, and possible anthropogenic impacts by comparing the knowledge of local small-scale fishermen (GA) and the regulars in the archipelago (GB). The data obtained were compared with those available in the literature to propose strategies for monitoring and preservation. Between August and December 2010, we applied the methods of participant observation, interviews-questionnaires and use of illustrative posters. Sixty-one interviews were conducted, from which 83.6% were selected by considering correct answers about the identification of the species on posters (morphological characteristics) and description of time of occurrence in the archipelago (July to December) as reported for the species in the literature. Regarding the seven questions analyzed statistically, a significant difference was found between the accounts of the two groups with respect to anthropic threats to T. truncatus . Gill-nets and the decrease of fishing resources were the main causes identified by the GA group whereas the GB group pointed to the disorganized use of space, pollution and predatory fishing as the factors that have threatened the common bottlenose dolphins. The use of ethnobiological data in conservation programs brings opportunities for the collaboration and participation of the community that is directly inserted into the ecosystem as well as a chance for locals to get involved in issues concerning the sustainability of the archipelago.