Diet of Hydromedusa tectifera (Testudines-Chelidae) in a mountain stream of Córdoba province, Argentina

BONINO, MARCELO F.; LESCANO, JULIÁN N.; HARO, JOSÉ G.; LEYNAUD, GERARDO C.

AMPHIBIA-REPTILIA

BRILL ACADEMIC PUBLISHERS

Año: 2009 p. 545 - 554

0173-5373

The diet of Hydromedusa tectifera occurring in two mountain streams in the province of Córdoba is describedthrough a comparative analysis of 154 individuals. Turtles were manually captured between August 2005 and August 2006from streams at the localities of Tanti and Flor Serrana. Before being released, turtles were stomach-flushed, and sex andcarapace length were recorded. The stomach contents were observed under stereomicroscope; prey items were identifiedand classified according to size and volume. The importance of the different items was quantified using the Index ofRelative Importance (IRI). Similarity in the diet between sexes and among size classes and seasons of an annual cycle wasevaluated using the simplified Morisita index. Trophic breadth was estimated with the Shannon diversity index. DetrendedCorrespondence Analysis (DCA) was used to evaluate differences in the diet between categories (sex, size classes). Fortysevenfood items belonging to the following taxa were identified: leeches, annelids, gastropods, arachnids, insects, and fishes.According to the IRI value, the most important items in the diet of H. tectifera were larvae of Trichoptera (IRI = 33.5),fishes (IRI = 30), and naiads of Odonata (IRI = 25.2). The relative importance of the items varied with size of turtles butnot with sex. Size of prey consumed increased with increasing turtle size. A greater trophic breadth was observed in smallerindividuals.