Medium and large-sized mammals in small forest remnants of the atlantic forest with anthropogenic influences in the north of Paraná

Abstract

The objectives of this study were to know the community of medium and large-sized mammals in four small forest remnants; collect data on the richness, diversity, equability, dominance and similarity of the animals in the environments studied; verify possibilities of maintenance of these existing populations; analyze the different types of traps used in the collection. Eight monthly collections were carried out, two in each fragment, between the months of July 2008 to June 2009, and three methodologies were used for identification: tracks in sand plots, direct search for remains and sightings in linear transect. Fourteen species were recorded in total. Low diversity is reflected in the dominance of species such as Cebus nigritus, Procyon cancrivorous, Cerdocyons thous and Cuniculus paca and also by the uneven abundance observed in the values of equability, where the least uniformity was found in area A (0.73) which coincides with the most dominance (0.29). It is possible to infer that a biotic homogenization of mammals is occurring, where richness declines and fewer opportunistic species resist in altered environments. The medium and large-sized mammals that are more specialist in habitat, diet or higher trophic level are sensitive to fragmentation, and replaced by generalist species, better adapted to human disturbance. As for the methodologies, the sand plots had the highest number of records (65%) and species (71%), being the most efficient one. Therefore, although small and not the ideal environment for some species, the forest remnants studied are additional areas for conservation of some opportunistic species, becoming important due to the continued loss of natural habitats and the small size of most conservation units found in Brazil.