INSTITUTO DE LIMNOLOGIA "DR. RAUL A. RINGUELET"
Unidad Ejecutora - UE
Feeding in syntopy: Diet of Hydromedusa tectifera and Phrynops hilarii (Chelidae)
ALCALDE, L; DEROCCO, N.N.; ROSSET, S.D.
CHELONIAN CONSERVATION AND BIOLOGY
CHELONIAN RESEARCH FOUNDATION
Lugar: Lawrence; Año: 2010 vol. 9 p. 33 - 33
Abstract. Stomach contents were obtained from 25 Hydromedusa tectifera and 47 Phrynops hilarii that live in sintopy in a pampasic stream on Buenos Aires province (Argentina). Both species are arthropod consumers being copepods, ostracods and hemipterans the most preferred items of P. hilarii, and copepods, ostracods, immature dipterans (mainly chironomids) and ephemeropteran larvae those of H. tectifera. Items that most contribute to the diet of both species are immature chironomids, corixids and belostomatids. Alimentary offer varies few among seasons being sligthly lower in winter months and in part of the summer. Diet diversity accompanishes offer changes by seasonal variation of prey item abundance in the diet of both species. Diet diversity is higher in P. hilarii than in H. tectifera. The first species is more generalist and its trophic niche is broader than in the other species. There is no niche overlap between them. No significative correlation between the size of turtles and length of prey items was found. There is no evidence that the long neck of H. tectifera relates to piscivorous habits since fish are a small fraction of its diet and arthropods constitute the bulk of the ingested items.