Passagens de fauna: Diretrizes para implantação e monitoramento da efetividade

Abstract

In addition to the benefits for infrastructure and economic development, highways have social and environmental impacts. Thus, a practical issue is "how to reduce the impacts of roads through mitigating measures." In this study, we analyzed the state of the art regarding the implementation of mitigating measures for the isolation of large wildlife populations, aiming to preserve the flow of individuals in habitats fragmented by roads and, more specifically, to minimize accidents resulting from collisions between vehicles and animals, which result in serious accidents. It is intended to support the mitigating measures with technical data, from the planning phase of new road layouts to the duplication and paving of existing highways. The general diagnosis is that there is a lack of systematized theoretical and technical material on the effects of roads on animal populations, and as a result, there is still difficulty in measuring the effectiveness of mitigating measures, such as wildlife crossings (WLCs), which necessarily require medium-long-term impact monitoring. A total of 167 bibliographic references (foreign and national) in road ecology were consulted, of which 122 were selected for this study, including articles, technical reports, monographs, and dissertations. The national panorama of road ecology points to a concentration of publications in the southern and southeastern regions of the country, with few publications for the northern and northeastern regions, carried out from 2000 to 2013. Most of these studies were based on surveys and identification of carcasses in highway sections, with few studies proposing to evaluate the efficiency of wildlife crossing structures. Generally, these studies indicate that mammals are the most affected animals, including some endangered species. Another aspect that deserves attention is the average monitoring time of only 1.07 years for WLCs, in the few cases where this practice occurred, a period considered inadequate to measure the effectiveness of procedures in attenuating negative effects of highways on wildlife. Based on the results of this sampling, we point out basic guidelines to increase the chances that mitigating measures will be functional, highlighting the need for monitoring capable of providing information before and after the implementation of WLCs.