Isotopic Discrimination Factors (Delta C-13 and Delta N-15) between Tissues and Diet of the Broad-Snouted Caiman (Caiman latirostris)

Autor(es)

Marques, Thiago S. ^[1] ; Bassetti, Luis A. B. ^[1] ; Lara, Neliton R. F. ^[1] ; Araujo, Marcio S. ^[2] ; Pina, Carlos I. ^[3] ; Camargo, Plinio B. ^[1] ; Verdade, Luciano M. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Ctr Energia Nucl Agr, Lab Ecol Isotop, BR-13416000 Piracicaba - Brazil

^[2] Univ Estadual Paulista, Dept Ecol, BR-13506900 Rio Claro - Brazil

^[3] CICyTTP CONICET, FCal UNER, FCyT UAdER Sede Diamante, RA-3105 Entre Rios - Argentina

• Tipo de documento: Artigo Científico
• Fonte: Journal of Herpetology; v. 48, n. 3, p. 332-337, SEP 2014.
• Citações Web of Science: 9

Resumo

Natural variation in stable isotope ratios is a useful tool in diet studies. However, the correct interpretation of isotopic data is reliant on proper estimates of discrimination factors. This study aimed to describe the magnitude of the discrimination factors of carbon and nitrogen isotopes between diet and tissues (Delta C-13(tissue-diet) and Delta N-15(tissue-diet)) of the Broad-snouted Caiman (Caiman latirostris) and to verify potential differences between age classes. The isotopic ratios of carbon and nitrogen (delta C-13 and delta N-15) were determined in samples of two tissue types (claw and scute) collected from 18 captive animals and in 15 samples of their diet. The Delta C-13(tissue-diet) was 1.2 +/- 0.1 parts per thousand for claw and 0.9 +/- 0.2 parts per thousand for scutes; the Delta N-15(tissue-diet) was 1.1 +/- 0.1 parts per thousand for claw and 0.8 0.2%0 for scutes. These values were much lower than the values assumed commonly in ecological studies (3-5 parts per thousand), and similar to a previous study with crocodilians. Our results emphasize the need to determine discrimination factors specific to taxa instead of assuming average values derived from the literature. (AU)

• Processo FAPESP: 06/60954-4 - Mudanças socioambientais no estado de São Paulo e perspectivas para a conservação
• Beneficiário: Luciano Martins Verdade
• Modalidade de apoio: Auxílio à Pesquisa - Programa BIOTA - Temático