The trophic niche of Mesoclemmys vanderhaegei (Testudines: Chelidae): evidence from stable isotopes

• Published in: Zoologia (Curitiba, Brazil) Vol. 34; pp. 1 - 6
• Main Authors: Marques, Thiago S., Brito, Elizângela S., Lara, Neliton R.F., Beloto, Luciana M., Valadão, Rafael M., de Camargo, Plínio B., Verdade, Luciano M.
• Format: Journal Article
• Language: English
• Published: Curitiba Sociedade Brasileira de Zoologia 01.01.2017
• Subjects: Acanthochelys spixii; Animals; Anthropic environment; Biology; Body size; Brazil; Chelidae; Chelodina longicollis; claws; Coexistence; Ecological distribution; Ecological monitoring; Ecological niches; Ecology; Exploitation; Females; Food; Food consumption; Food resources; freshwater turtle; habitat preferences; Habitat selection; Habitat utilization; Habitats; Hydromedusa maximiliani; information; intraspecific variation; Isotopes; isotopic niche; males; Niches; Ontogeny; Paraguay; population; Ratios; Reptiles; Reptiles & amphibians; Resource exploitation; sampling; sexual niche; Stable isotopes; Statistical methods; turtles; Variation; width; ZOOLOGY; Brazil; Paraguay; Anthropic environment; freshwater turtle; isotopic niche; sexual niche
• ISSN: 1984-4689; 1984-4670; 1984-4689
• DOI: 10.3897/zoologia.34.e19985

Ecological niche is the multidimensional space comprising the resources used by an organism. Intraspecific variation in resource exploitation is common in reptile populations to maximize coexistence of individuals. The use of stable isotope analysis is an effective tool when there are variations in resource exploitation, since it can provide quantitative information about food consumption and habitat use. Mesoclemmys vanderhaegei (Bour, 1973) is a medium-sized turtle with a limited distribution in south central Brazil and Paraguay. In spite of that, little is known about its ecology. In this study we used stable isotope analysis to understand the intraspecific trophic niche variation in M. vanderhaegei at Serra das Araras Ecological Station, state of Mato Grosso, Brazil. The isotopic ratios of δ15N and δ13C were determined in claw samples collected from 14 males and 14 females. Isotopic niche width values were not statistically different between the sexes, there was a high degree of overlap between sexual niches and there were no relationships between isotopic compositions and body size. These results suggest that individuals of both sexes and throughout their ontogenetic development exploit food resources with the same isotopic baseline.