Perspectives in Ecology and Conservation Perspectives in Ecology and Conservation
Nat Con 2016;14:8-13 DOI: 10.1016/j.ncon.2016.01.001
Research Letters
Do the size and shape of spatial units jeopardize the road mortality-risk factors estimates?
Clara Griloa,, , Thálita de Resende Cardosoa, Ricardo Solarb, Alex Bagera
a Post-Graduate Program in Applied Ecology, Brazilian Center for Studies on Road Ecology, Universidade Federal de Lavras, Lavras, MG, Brazil
b Laboratory of Ecology Communities, Department of Entomology, Universidade Federal de Viçosa, Viçosa, MG, Brazil
Received 07 January 2016, Accepted 18 January 2016
Abstract

We aimed to evaluate the role of spatial units with different shapes and sizes on road-kill modeling for small vertebrate species. We used the road-kill records of two reptiles, water snake (Helicops infrataeniatus) and D’Orbigny's slider turtle (Trachemys dorbigni), and three mammals, white-eared opossum (Didelphis albiventris), coypu (Myocastor coypus) and Molina's Hog-nosed skunk (Conepatus chinga). Hierarchical partitioning was used to evaluate the independent influence of different land-use classes on road-kill by varying the shape and size of the spatial units. Variables that most explained road-kill were consistent over the different spatial unit types. The standard size seemed to be a reasonable solution for these species. Prior analysis with several sizes and shapes is needed to identify the appropriate spatial unit to model road-kill occurrence for larger vertebrates with different history traits.

Keywords
Multi-scale analysis, Road segments, Buffer analysis, Wildlife–vehicle collisions, Hierarchical partitioning