| Texto completo | |
| Autor(es): |
Rangel, Bianca de Sousa
[1]
;
Hammerschlag, Neil
[2, 3]
;
Sulikowski, James A.
[4]
;
Moreira, Renata Guimaraes
[1]
Número total de Autores: 4
|
| Afiliação do(s) autor(es): | [1] Univ Sao Paulo, Inst Biociencias, Dept Fisiol, Lab Metab & Reprod Organismos Aquat, Rua Matao, Travessa 14, 321, Cidade Univ, BR-05508090 Sao Paulo, SP - Brazil
[2] Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Miami, FL 33149 - USA
[3] Univ Miami, Leonard & Jayne Abess Ctr Ecosyst Sci & Policy, Coral Gables, FL 33146 - USA
[4] Arizona State Univ, Sch Math & Nat Sci, Glendale, AZ 85306 - USA
Número total de Afiliações: 4
|
| Tipo de documento: | Artigo Científico |
| Fonte: | MARINE ECOLOGY-PROGRESS SERIES; v. 664, p. 149-163, APR 15 2021. |
| Citações Web of Science: | 0 |
| Resumo | |
Knowledge of the nutritional requirements of apex predators is key for determining ecological interactions. However, an understanding of how diet is influenced by reproduction, and the consequences of foraging variation on the nutritional status of a predator, is limited. Here, we used short-term dietary markers (plasma and whole-blood fatty acids) integrated with reproductive hormones (17 beta-estradiol and testosterone) and ultrasonography as a non-lethal approach to investigate the effect of life stage on nutritional status and trophic dynamics of female tiger sharks Galeocerdo cuvier. Despite their generalist feeding behavior, female tiger sharks fed on different food sources and/or modulated their fatty acid metabolism depending on the reproductive context. This suggests some adjustment in their nutritional requirements associated with changes in their reproductive state. Plasma and whole-blood fatty acids indicated distinct dietary sources across life stages, with a high dependence on coastal/benthic food resources during juvenile life stages, and on pelagic/oceanic and reef-associated food resources during adult life stages. Higher percentages of highly unsaturated omega-3 fatty acids found in females during their reproductive cycles suggest the dependency on these fatty acids as a source of metabolic energy during reproduction. A high percentage of arachidonic acid (ARA) found in plasma of gravid females suggests the possibility of a selective diet of ARA-rich prey species and/or selective mobilization of ARA from stored energy during gestation. Based on our findings, we propose a conceptual model of expected changes in nutritional and trophic markers across life stages of female tiger sharks. (AU) | |
| Processo FAPESP: | 17/25273-0 - Ecofisiologia e relações tróficas de elasmobrânquios: biomarcadores como ferramentas para conservação |
| Beneficiário: | Bianca de Sousa Rangel |
| Modalidade de apoio: | Bolsas no Brasil - Doutorado |
| Processo FAPESP: | 14/16320-7 - Impactos das mudanças climáticas e ambientais sobre a fauna: uma abordagem integrativa |
| Beneficiário: | Carlos Arturo Navas Iannini |
| Modalidade de apoio: | Auxílio à Pesquisa - Programa de Pesquisa sobre Mudanças Climáticas Globais - Temático |