Análise de encalhes de tartarugas-marinhas no Litoral Cearense entre 2015 e 2020

Abstract

In Brazil, there are 5 species of sea turtles: Chelonia mydas, Eretmochelys imbricata, Caretta caretta, Lepidochelys olivacea, and Dermochelys coriacea. Despite being protected by law, all species are listed on the IUCN Red List. The Verdeluz Institute, through the GTAR project, carries out activities focused on the study and conservation of these animals, conducting beach monitoring to identify nests and strandings, and receiving reports from the population about them. A total of 322 strandings were recorded on the coast of Ceará, and data on date, location, species, curved carapace length and width, age range, sex, conservation status, presence of fibropapillomatosis, and interaction with fishing and oil were tabulated. Additionally, tidal data provided by the Brazilian Navy, such as average tide elevation, wind speed, and relative humidity, were included. From December 2015 to December 2020, there were no recorded leatherback turtle strandings, while the green turtle accounted for 203 strandings, representing 63.04% of the records. Females represented the majority of strandings in all species (42.95%), including unidentified individuals, corroborating the tendency for females to approach the coast. Most strandings were classified as advanced decomposition, indicating mortality at sea before stranding, making data collection difficult. The year with the highest number of recorded strandings was 2019 (41.61%), which coincided with an oil spill on the Northeast beaches of Brazil. 83.3% of the stranded hatchlings were hawksbill turtles, representing the nesting area for the species. Correlation tests indicated a lower tendency for larger animals to strand, as well as during high tides, but there is limited literature on these topics.