Avaliação das ocorrências de predação em ninhos de tartarugas marinhas na Bacia Potiguar: distribuição, predador dominante e estratégias para redução

Abstract

The Potiguar Basin region is located, for the most part, on the northern coast of Rio Grande do Norte State and is considered an important nesting area for two species of sea turtles: Olive Ridley (Lepidochelys olivacea) and Hawksbill (Eretmochelys imbricata). Both species are endangered mainly due to various anthropogenic threats, such as bycatch in fishing nets, vehicle traffic and the presence of solid waste on the beach. After nesting, the eggs go through an incubation period of, on average, 60 days and from the moment they are exposed on the beach, they become more vulnerable to anthropic and natural predation. The objective of the study was to evaluate the occurrences of predation of nests of sea turtles present in the region of the Potiguar Basin, aiming at the conservation of the species. The study was carried out using data from 12 years of beach monitoring, made by the Projeto Cetáceos da Costa Branca (PCCB-UERN). We found that the predation rate in the region is approximately 20.5%. In addition for being irregularly distributed between years, predation was more frequent between the months of January and April. Nest predation events were concentrated in Macau/RN around a dominant predator: the fox species Cerdocyon thous.The individual characteristics of each nest, such as depth and diameter measurements, did not influence predation events and no relationship was observed between incubation time and nest predation. In order to control the number of predated nests in the Potiguar Basin region, it was suggested the use of plastic screens and cages and the use of flags close to the nests to prevent the approach of the predator and, consequently, the consumption of eggs.