Portal de Periódicos da CAPES

Rythmes d’activité et régimes alimentaires de Proechimys cuvieri et d’ Oryzomys capito velutinus (Rodentia) en forêt guyanaise

1982; Volume: 36; Issue: 3 Linguagem: Inglês

10.3406/revec.1982.4382

0249-7395

M. Guillotin,

Evolution and Paleontology Studies

Proechimys cuvieri and Oryzomys capito velutinus have been studied in two forests of French Guyana, on the Arataye River and at Saint-Elie. Whereas both areas are covered by mature rain forest, the Saint-Elie site includes a 25 ha parcel of 4 year old second growth. The daily movements of the animals were followed by radio-tracking, and the use of a fluorescent powder, sprayed on a number of individual rodents, and whose traces on the ground and/or vegetation were detected with a UV lamp. Various methods were also used to study the diet of the two species : analysis of stomach contents, identification of partially consumed food items and of fruits found in nests or resting places (only Proechimys cuvieri hoards fruits in food caches), as well as «cafeteria » experiments in captive conditions. Both species are strictly nocturnal in their activities, with two activity peaks during the course of the night. In P. cuvieri , males cover twice as much distance per night as females do. In both species, males have larger home ranges than females. Proechimys and Oryzomys are mostly frugivorous, the diet varying with the sex of the animal, the season and the forest type. Proechimys cuvieri eats more insects during the dry season, when fruit production is low, than during the rains. Males are more frugivorous than females, and both sexes are almost exclusively frugivorous in young second growth. There is a difference in size of the fruits consumed by the two sympatric species, which parallels their difference in body size. The trophic impact of Proechimys cuvieri on the available fruit resource is low, but the animal quite likely plays an important role in seed dispersal.