Vertebrados atropelados na Amazônia: monitoramento em longo prazo, influência do fluxo de veículos e alternância de hotspots em um trecho da Rodovia BR-174, Brasil

Abstract

In this study, we present and analyze the records of a 21-years monitoring program of vertebrate road-kills along 121 km of the BR-174 highway inside the Waimiri Atroari Indigenous Territorry (TIWA). The TIWA is a well-preserved area with high diversity of wild vertebrates located in Central Amazon. To assess the dynamics of road-kills, we identified the groups most killed and for each group, we investigated the influence of rainfall and vehicle traffic rates over the number of road-kills by using Generalized Linear Mixed Models (GLMM). To identify scales and areas of significant road-kill clusters (hotspots) over eight years, we used a modified K statistic and the HotSpot 2D statistic. From 1997 to 2017, 11 ,635 vertebrates were killed by car collisions. From these records, mammals and reptiles are the most representative classes followed by birds and amphibians. Vehicle traffic rate explained road-kill variation for all taxa, and rainfall was important to explain mortality only for mammals, but a negative relation. Hotspots were different among taxa and over years, but some remained or oscillated over time within each group, which we believe is related to the abundance of animals in the surroundings or to variation in resource availability. Therefore, vehicle traffic rates should be incorporated in road-kill studies, even in low traffic highways, and hotspots should be monitored from medium to long-term so that the choice and positioning of mitigation actions consider relevant factors and areas where kills aggregate along roads over time.