Inventário de pequenos mamíferos não voadores no Parque Estadual da Serra Azul – Barra do Garças, MT

Abstract

The diversity of organisms can be affected by the structural complexity of the environment and also by seasonal variations in climate. The objective of this study was to inventory small non-flying mammals in different physiognomies in the Serra Azul State Park (PESA) analyzing the composition and richness of the community as a function of differences in the areas of occurrence of species and climatic seasonality in the region. The Park has forest and savanna areas and is located in a region with strong climatic seasonality, with a dry season (May-September and a wet one (October-April). We tested the hypothesis that forest areas have greater structural complexity. more species would be found while during the rainy season, considered less restrictive to animal activities, more individuals would be captured. We inventoried marsupials and small rodents using 360 traps, with 180 Sherman and 180 Tomahawk suitable for capturing live animals with up to 1 kg. The traps were installed in areas of cerrado (14) and forest (4) where they remained for 24 nights, being 12 nights in the rainy season and 12 in the dry season, a sampling effort of 8640 traps-night. belonging to 8 species, four marsupials and four rodents. The most abundant species was Thrichomys cf. laurentius, with 94 individuals all capt. in cerrado areas. In cerrado, 6 spp. (103 individuals) were captured and in forest, 6 spp. (14 individuals). Weighted by the greater collection effort in the cerrado, the richness in the forest was significantly higher than in the Cerrado. There was no significant difference in relation to the number of individuals or species observed in the dry season (53 individuals) in relation to the rainy season (63 individuals). Despite the lower sampling effort and the small number of individuals sampled, the estimated species richness was significantly higher in the forest than in the cerrado, corroborating the hypothesis of greater diversity in structurally more complex environments. On the other hand, the number of individuals and species did not vary seasonally indicating that the species must be resident and active throughout the year.