Spatiotemporal variation in human-wildlife conflicts along highway BR-262 in the Brazilian Pantanal

The Pantanal of Brazil, the world's largest freshwater wetland, supports a large diversity of species and is under continually increasing pressure from human development, including vehicle collisions with wild animals. We examined decadal, annual, and spatial variation in wildlife-vehicle collisions along highway BR-262 in the southern Pantanal, and specifically: (1) what is the rate of roadkill along BR-262, and did it increased over the previous decade, (2) which species are frequently victims of collisions and does this vary annually along the highway's length, and (3) what anthropogenic or environmental factors may influence this variation and how can the context of collisions inform mitigation? We sampled the highway monthly, between April 2011 and June 2012, stopping when roadkill was observed to identify species and collect GPS coordinates and a photographic record. Data was analyzed temporally and in relation to traffic volume and precipitation, and imported into a GIS and analyzed spatially and in relation to elevation. We recorded 518 carcasses from 40 species over the 15 sampling periods. The rate of roadkill incidents was 1 every 6.2 km, a tenfold increase since 2002, and is now one of the highest in Brazil. IUCN Red List species were observed, including lowland tapir, giant anteater, and marsh deer. At the lowest elevations, during seasonal wetland inundation the causeway embankment is sought for refuge, increasing collision probability. Mitigation measures tied to seasonal flood pulse variation along the causeway may reduce the high rate of wild animal mortality and loss of biodiversity.