Influence of Life History Traits on Trophic Niche segregation between two similar sympatric Tupinambis lizards

LOPEZ JURI, GUADALUPE; NARETTO, SERGIO; MATEOS, CAROLINA; CHIARAVIGLIO, MARGARITA; CARDOZO, GABRIELA

South American Journal of Herpetology

Brazilian Society of Herpetology

Año: 2015 vol. 10 p. 132 - 142

1808-9798

Segregation of habitat resources is an important mechanism that allows thecoexistence of species. The diet is an important and dynamic component that might generate interactions among co-existing species. Differences in food resource use between related sympatric species have been frequently associated with divergence in multiple phenotypic traits; hence, it is interesting to explore how phenotypic differences allow sympatric species to minimize niche overlap. We aimed at evaluating trophic niche segregation between Tupinambis merianae and Tupinambis rufescens in relation to life history traits in a sympatric zone. We compared the volume of the stomach food items between species considering sexual dimorphism, body size classes, sexual maturity and reproductive activity. The obtained Morisita´s index indicated trophic nicheoverlap between T. merianae and T. rufescens; however, considering particular food items, we observed differences in diet composition between species. Moreover, our results indicate that body size, sexual maturity and reproductive activity are relevant factors influencing the diet of these species. Life-history traits of these two Tupinambis species are important because they shape diet composition, contributing to interspecific segregation of the trophic niche and, thus, allowing species coexistence.