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Providing evidence to improve practice

Individual study: Use of highway underpasses by large mammals and other wildlife in Virginia: factors influencing their effectiveness

Published source details

Donaldson B. (2007) Use of highway underpasses by large mammals and other wildlife in Virginia: factors influencing their effectiveness. Transportation Research Record, 2011, 157-164


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

Install tunnels/culverts/underpass under roads Terrestrial Mammal Conservation

A study in 2004–2005 at seven sites along roads through forest in Virginia, USA (Donaldson 2007) found that white-tailed deer Odocoileus virginianus used underpasses to cross the road but black bears Ursus americanus did not. White-tailed deer crossed through four of seven underpasses monitored, with a total of 1,107 crossings detected. Black bears approached one underpass entrance three times, but did not cross through. Other mammals recorded in underpasses included opossums Didelphis virginiana, bobcats Lynx rufus, red foxes Vulpes vulpes, coyotes Canis latrans, raccoons Procyon lotor and groundhogs Marmota monax as well as squirrels and mice (see paper for details). Seven underpasses were monitored. Five were culverts (1.8–6.1 m wide, 1.8–4.6 m high and 21–79 m long). Two were crossings under bridges (13–94 m wide, 5–14 m high and 10–18 m long). Underpasses were not fenced and most had a narrow water section. Underpasses were monitored from June 2004 to May 2005, using one or two camera traps at each entrance.

(Summarised by Ricardo Rocha)