Sucesso de ninhos artificiais em diferentes ambientes do Campus da Universidade Federal Rural do Rio de Janeiro

Abstract

Some generalist bird species can find good conditions for survival and reproduction in antropic habitats. Among other factors that would affect species establishment in a given habitat, one can cited the offer of nest material and the nest predation rates. Aiming the evaluation of the reproductive success of some nesting bird species in the Campus of the Universidade Federal Rural do Rio de Janeiro, in Seropédica, Rio de Janeiro, Brazil, we have searched for nests every week in two substratcs (ground and vegetation) in four habitats (pounds, grassland, eucalypt plantation and forest) between January 23, 2003 and October 10, 2004. To estimate the predation effect on the reproductive success, 80 artificial nests were installed, each one having an egg of Japanese quail (Coturnix coturnix), disposed in the same habitats as mentioned, both in the rainy and dry seasons. Data were collected during the nests visit, three days in a week. A total of 38 nests were found, including those of Estrilda astrild (10), Turdus spp. (7), Columbina talpacoti (4), Coereba flaveola (3) and Sicalis flaveola (2). Thirteen nests were abandoned, and they material were collected and analyzed; the main components found vegetal pieces as straws and roots. Generally speaking, the artificial nests were more predated in the following order: forest, eucalypt plantation, grassland and pound. No statistically significant differences in the predation rates were observed between nests on the ground and in the vegetation. However, the predation rates were higher in the rainy than is the dry season.