Influential factors on the over wild vertebrates in central region of Rio Grande do Sul, Brazil

Abstract

The habitat loss or fragmentation and reduced connectivity between habitats are common features in areas with roads. These impacts have close liaison with trampling of wild vertebrates. This study aimed to identify and quantify the factors that influence directly and indirectly these accidents. Four sections (North, South, East and West) at 100 km of highway BR 158, 287, 392 and RST 241 were monitored, through a different route every week in each trip, totaling 48 in the period from December 2008 to December 2009. The starting point of the routes was the outskirts of Santa Maria, zero km of the route, returning by the same BR occurred after traveling 100 km on the highway. 829 individuals were recorded, belonging to four classes, 43 families and 83 species. The percentage of roadkill mammals was 51.6%; 31.9% of birds; 11.7% of reptiles; and 4.7% of amphibians. The sampling effort of 9600 km resulted in an average of 0.086 roadkill/km. The most roadkilled vertebrates were in the class of mammals the possum-to-ear-White (Didelphis albiventris), 135 records; in birds, eared dove (Zenaida auriculata), with 39 records; in reptiles, tegu lizard (Tupinambis merianae), with 42 records; and amphibians in the frog cururu (Rhinella icterica), with 20 animals. The events were affected by seasonality, type of matrix surrounding the accident, the rainfall and temperature. No effective mitigation measures were identified on the slopes. Installation media for the implementation of highways by wildlife in identified critical areas was suggested. However, more studies are needed in order to identify specific features of the highways and species that are present in the region.

Key words: wildlife, road traffic, running over.