Influência de uma rodovia na distribuição da diversidade de aves no Parque Estadual do Espinho

Abstract

The ecological phenomenon called “edge effect”, that it can be caused by highways, mentions to the consequences of the spalling of the landscape on plants and animals that occupy certain habitat. The birds are between the groups more affected by the impacts of the highways, either for the effect barrier or effect avoidance, generated for the formations of the edges or the running overs. These impacts disclose in the structure of the communities of birds and are perceived mainly next the edges to the highways. The Espinilho State Park (ESP) is considered an ornithological special area interest being the only occurrence area of some species of birds of Brazil. The aim of this study was to estimate the influence of highway BR472 on the diversity of birds and discuss which the ecological characteristics are more important in the diversity distribution of birds. For the collection of the data two areas were sampling selected inside of the park and along Highway BR472. In each area three transects with different distances were established, parallels the highway, and divided in five sampling points, with 100 meters of distance. The observer remained per 10 minutes in each point. They were registered the species and the number of individuals seen in each point. For comparison ends, were selected sampling points more susceptible to the edge effect and less susceptible points. For comparison of the ecological characteristics the species of birds were categorized in accordance with the habit alimentary and use of the habitat. The highway that cuts the ESP influences in the distribution and composition of the species of birds. The increase of the bird richness, together with the partial increase of the abundance with the detachment of the highway corroborates this fact. Species of birds with granivorous, omnivorous alimentary habits and that they tolerate anthropic areas and of forest edge occupy next areas the highway. Birds with alimentary habits insectivorous, that use field habitat with priority, humid areas and Espinilho occur in more distant areas of the highway. The edge effect generated for the highway in the Espinilho State Park manifest if of more accentuated form in the first 250 meters and of softer form up to 500 meters of the highway. Our data indicate that the edges effect generated for highways modify the composition of species and structure of the communities of birds in the Espinilho State Park. The communities of birds suffer for the exclusion or population reduction from some species from the areas from edge generated for the highway.