Effects of roads on the vertebrates diversity of the Indigenous Territory Paresi and its surrounding
Roadkill impact is still underestimated due to the lack of knowledge of its intensity and effect on animal populations. To assess differences between animal roadkills on roads in distinct landscapes, this study recorded mesoand megavertebrate roadkills along 50 km during a year in two highways in the transitional area of Amazonia/Cerrado in Tangará da Serra, Mato Grosso: MT-358 and MT-235, the latter crossing the Paresi Indigenous Land. We assessed roadkill rates and points with higher rates of roadkills, recording the most impacted species, seasonal effects, biomass loss, activity period of species, and traffic volume. We recorded 178 roadkills in 4,950 km travelled, a rate of 0.035 animal/km-travelled. Mammals were the most impacted with 135 roadkills (75.8%), followed by reptiles (6.2%), amphibians (5.6%) and birds (5.1%). Among mammals 51.1% were Carnivora, and the most impacted species was Cerdocyon thous (n = 42). On highway MT-358 (human-modified landscape), we recorded 155 roadkilled mammals, and the most impacted were C. thous (23.9%) and Euphractus sexcinctus (13.5%). Whilst on highway MT-235 (Paresi Indigenous Land), we recorded 23 roadkilled mammals, and the most impacted were Myrmecophaga tridactyla (26.1%) and C. thous (21.7%). The low roadkill rate in the Paresi Indigenous Land might be related to the presence of fauna pathways along the highway and the availability of a forested landscape.
Response of Wild MaMMals To seasonal shRinking-and-expansion of habiTaTs due To flooding RegiMe of The panTanal, bRazil
The pantanal is a large savanna wetland (138,183 km 2 in brazil), important for its wildlife, fed by tributaries of the upper paraguay River, center of south america ( brazil, touching bolivia and paraguay). uplands are plateaus (250-1,200 m high, 215,000 km 2 in brazil) and flatland is the pantanal (80-150 m high, 147,574 km 2 in brazil). Rivers are slow moving when they meet the flatland (slope 0.3-0.5 m/km east-west; 0.03-0.15 m/km north-south), periodically overflowing their banks, creating a complex seasonal habitat range. Recurrent shallow flooding occupies 80% of the
VERTEBRATE ROAD MORTALITY PREDOMINANTLY IMPACTS AMPHIBIANS
—One potential contributor to global amphibian decline is mortality due to traffic (“road-kill”). Most studies of road-kill have focused on large mammals, but relatively little research has evaluated the impact of road-kill on other wild animals. We conducted multi-species road-kill surveys in Indiana, USA to develop a road-kill database and to identify habitat characteristics associated with road-kill. Four different routes were surveyed for vertebrate mortalities twice weekly from 8 March 2005 to 31 July 2006. We recorded 10,515 mortalities representing > 60 species (n = 496 surveys). The most common species we encountered were Bullfrogs (Rana catesbeiana, n = 1,671), Virginia Opossums (Didelphis virginianus, n = 79), and Chimney Swifts (Chaetura pelagica, n = 36). We recorded thousands of anuran, but most (> 7,500) could not be identified to species. Habitat variables that best predicted vertebrate mortality were water, forest, and urban/residential areas. Overall, our results suggested that road mortality impacts a wide variety of species and that habitat type strongly influences frequency of road-kill. Amphibians may be especially vulnerable because they often migrate en masse to or from breeding wetlands. Clearly, road-kill is a major source of amphibian mortality and may contribute to their global decline.