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Providing evidence to improve practice

Individual study: Barrier walls reduce wildlife mortality on a highway in Paynes Prairie State Reserve, Florida, USA

Published source details

Dodd C.K., Barichivich W.J. & Smith L.L. (2004) Effectiveness of a barrier wall and culverts in reducing wildlife mortality on a heavily traveled highway in Florida. Biological Conservation, 118, 619-631


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Install barrier fencing along roads Amphibian Conservation

A controlled, before-and-after study in 2001–2002 of a barrier wall linking culverts along a highway in Florida, USA (Dodd, Barichivich & Smith 2004) found that the wall significantly decreased amphibian road deaths, apart from treefrogs (Hylidae), which could climb over. A total of 19 amphibian road-kills were found on the 3 km section with barrier, compared to 326 kills on the 500 m section with no barrier. Treefrogs were excluded from these figures. Treefrog mortality increased after construction of the barrier and culverts (from 149 to 194 over three survey sections). In 2001, a 1 m high concrete wall with a 15 cm overhang was erected along the highway, parallel to a wetland prairie. The wall extended 3 km on each side of the road. Concrete culverts under the highway were increased from four to eight. The highway and grass verge were monitored from 200 m before the start of the barrier until 200 m past the end. Monitoring was undertaken on three consecutive days from dawn each week from March 2001 to March 2002.