ABSTRACT
This study evaluates the reproductive and ecological similarity between loggerhead sea turtle (Caretta caretta) and Hawksbill sea turtle (Eretmochelys imbricata) two species of sea turtles on the southern coast of Bahia (Brazil) during two breeding seasons (October to April 2013 to 2015). The study covers a 10-km area composed of three beaches, Pompilho, Itacarezinho and Patizeiro beach, which are 5, 3, and 2 km long, respectively. Daily field surveys were performed for 102 days to assess patterns between the studied species, using the non-metric multidimensional scaling order and the Spearman correlation analysis to obtain the oviposition pattern of the two species. Moreover, Kruskall-Wallys tests were performed to review the differences in the number of hatchlings on the three beaches. The NMDS proved the species are very similar from an ecological perspective since as there were three clear groupings in terms of the number of hatchlings on the three beaches. With reference to the number of nests, a negative correlation was observed in the two species. Regarding the hatching activity of both species on the three beaches studied, a larger amount of C. caretta and E. imbricata hatchlings was found on Pompilho beach, followed by Patizeiro and Itacarézinho. These findings influence management strategies to reduce anthropogenic impact and contribute to the conservation of these two endangered sea turtle species.
Subject(s)
Turtles , Animals , Brazil , Female , Oviposition , ReproductionABSTRACT
This study evaluates the reproductive and ecological similarity between loggerhead sea turtle (Caretta caretta) and Hawksbill sea turtle (Eretmochelys imbricata) two species of sea turtles on the southern coast of Bahia (Brazil) during two breeding seasons (October to April 2013 to 2015). The study covers a 10-km area composed of three beaches, Pompilho, Itacarezinho and Patizeiro beach, which are 5, 3, and 2 km long, respectively. Daily field surveys were performed for 102 days to assess patterns between the studied species, using the non-metric multidimensional scaling order and the Spearman correlation analysis to obtain the oviposition pattern of the two species. Moreover, Kruskall-Wallys tests were performed to review the differences in the number of hatchlings on the three beaches. The NMDS proved the species are very similar from an ecological perspective since as there were three clear groupings in terms of the number of hatchlings on the three beaches. With reference to the number of nests, a negative correlation was observed in the two species. Regarding the hatching activity of both species on the three beaches studied, a larger amount of C. caretta and E. imbricata hatchlings was found on Pompilho beach, followed by Patizeiro and Itacarézinho. These findings influence management strategies to reduce anthropogenic impact and contribute to the conservation of these two endangered sea turtle species.
Este estudo avalia a semelhança reprodutiva e ecológica entre a tartaruga cabeçuda (Caretta caretta) e a tartaruga-de-pente (Eretmochelys imbricata) duas espécies de tartarugas marinhas no litoral sul da Bahia (Brasil) durante duas estações reprodutivas (outubro a abril de 2013 a 2015) . O estudo abrange uma área de 10 km composta por três praias, Pompilho, Itacarezinho e praia do Patizeiro, com 5, 3 e 2 km de extensão, respectivamente. Foram realizados levantamentos diários de campo durante 102 dias para avaliar padrões entre as espécies estudadas, utilizando a ordem de escala multidimensional não métrica e a análise de correlação de Spearman para obter o padrão de oviposição das duas espécies. Além disso, testes de Kruskall-Wallys foram realizados para revisar as diferenças no número de filhotes nas três praias. O NMDS provou que as espécies são muito semelhantes do ponto de vista ecológico, pois havia três agrupamentos claros em termos do número de filhotes nas três praias. Com relação ao número de ninhos, foi observada correlação negativa nas duas espécies. Em relação à atividade de eclosão de ambas as espécies nas três praias estudadas, uma maior quantidade de filhotes de C. caretta e E. imbricata foi encontrada na praia do Pompilho, seguida de Patizeiro e Itacarézinho. Esses achados influenciam as estratégias de manejo para reduzir o impacto antropogênico e contribuir para a conservação dessas duas espécies de tartarugas marinhas ameaçadas de extinção.