Análise temporal da dieta de toninha (Cetartiodactyla: Pontoporia blainvillei) na FMA IIb, sudeste do Brasil

• Autor(a) principal: Grellet, Gabriel Mendonça
• Data de Publicação: 2023
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: https://hdl.handle.net/11449/252408
• topic: Trophic ecology; Feeding habits; Small dolphin; Coastal cetacean; Stomach content; Ecologia trófica; Hábitos alimentares; Cetáceos; Toninhas

In the Western South Atlantic, the franciscana (Pontoporia blainvillei) is a species of small coastal dolphin, threatened by indcidental catch in fishing gillnets. Information about the species' feeding habits is still scarce in the northern portion of its distribution (FMAs I and II). This study aimed to describe and evaluate the importance its feeding habits by analyzing the stomach contents of 206 carcasses from strandings and incidental captures between the years 2015 and 2021, on the south-central coast of São Paulo. We identified 6932 otoliths and 1126 cephalopod beaks, totaling 20 prey taxa identified: 17 teleosts and 3 cephalopods. The species that presented the highest index of relative importance (∑IRI > 90%) were respectively Stellifer rastrifer; Pellona harroweri; Doryteuthis plei; Lolliguncula brevis; and Paralonchurus brasiliensis. Thus franciscanas presented piscivorous and teutophagous habits. The greater contribution of S. rastrifer to the diet differs from previous studies conducted in the same region. We did not record significant differences between the importance of these species for sexes, ages and seasons. The temporal analysis of the diet showed a significant difference between the years studied.