Trophic relationships and use of area of two sympatric small cetaceans in the Southwestern Atlantic Ocean determined by carbon and nitrogen stable isotopes

Autor(es)

Campos, Laura B. ^[1] ; Santos, Marcos Cesar de O. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Lab Biol Conservacao Mamiferos Aquat LABCMA, Dept Oceanog Biol, Inst Oceanog, Praca Oceanog 191, Cidade Univ, BR-05508120 Sao Paulo, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Anais da Academia Brasileira de Ciências; v. 93, n. 2 2021.
• Citações Web of Science: 0

Resumo

Abstract As cetaceans are sentinels of the marine environment, studying their life history is of utmost importance in understanding their habits and their interaction with the environment. To achieve this goal, it is important to study their ecological niches through the investigation of their habitat use patterns and trophic relationships. This study aimed to evaluate if there are differences in the habitat use patterns and the trophic ecology of franciscana (Pontoporia blainvillei) and Guiana dolphins (Sotalia guianensis) accidentally caught off the south coast of São Paulo State, and Guiana dolphins biopsied in the Cananeia estuary, southeastern Brazil, based on the carbon and the nitrogen stable isotopes analysis. Isotopic ratios were estimated from skin samples. The isotopic niche size and overlap were calculated using the SIBER package (R software). The gathered results showed evidence of spatial segregation between Guiana dolphins and franciscanas. The Guiana dolphins sampled inside and outside the estuary showed evidence of trophic and spatial segregation. No difference in isotopic values between sexes was found for both species. Such differences between franciscanas and Guiana dolphins were expected as both species have distinct life histories as a result of different evolutionary pathways. (AU)

• Processo FAPESP: 10/51323-6 - Capturas acidentais de pequenos cetáceos em atividades pesqueiras no litoral sul paulista: buscando subsídios para formulações de política de conservação
• Beneficiário: Marcos César de Oliveira Santos
• Modalidade de apoio: Auxílio à Pesquisa - Parceria para Inovação Tecnológica - PITE