Road traffic and nearby grassland bird patterns in a suburbanizing landscape.

Synopsis: The study examined the effects of road networks on suburbanizing ecosystems, using grassland bird distribution to explore the relative ecological importance of variables relative to linear disturbances and the effect of road traffic volumes. The study found that roads primarily affect ecological variables for 1) distance from road and 2) habitat patch size. The study also found that road traffic volumes are correlated to avian distribution, suggesting that traffic volumes have an ecological effect. The research suggests that traffic noise is the primary ecological effect of roads and that roads with higher traffic volumes extend the road effect zone outwards of 100 m and up to 1,200 m.

Given the ecological variables that are affected by roads, the study recommends that transportation facilities with high road volumes such as highways should be located away from natural resource areas and that open patches with quality microhabitats should be maintained away from highways. Mitigation of these effects should include efforts to reduce traffic volumes and decrease roadway noise through roadway and vehicular design measures. Further, broader process solutions are required at the transportation and regional planning levels that consider the road-effect zone in all planning projects such that mobility and ecological objectives can be achieved.