Factors associated with use of wildlife underpasses and importance of long-term monitoring

  • Published source details Gagnon J.W., Dodd N.L., Ogren K.S. & Schweinsburg R.E. (2011) Factors associated with use of wildlife underpasses and importance of long-term monitoring. The Journal of Wildlife Management, 75, 1477-1487.


This study is summarised as evidence for the following.

Action Category

Install barrier fencing and underpasses along roads

Action Link
Terrestrial Mammal Conservation
  1. Install barrier fencing and underpasses along roads

    A replicated study in 2002–2008 along a highway in Arizona, USA (Gagnon et al. 2011) found that wildlife underpasses, in areas with roadside ungulate-proof fencing, were used by mammals. Six underpasses were approached 14,683 times by wild mammals, of 15 species. Of all animals recorded (which included also 450 records of domestic animals and one of a bird) 72% crossed through underpasses. Elk Cervus canadensis accounted for 70% of visits by wild mammals to underpasses, white-tailed deer Odocoileus virginianus for 13% and mule deer Odocoileus hemionus for 7%. Other crossings comprised coyote Canis latrans (1%), gray fox Urocyon cinereoargenteus (2%), raccoon Procyon lotor (2%) and other mammals (4%). Reconstruction of a 27-km stretch of State Route 260 was undertaken in 2000–2006 and included creation of 11 large wildlife underpasses, connected to ungulate-proof fencing. Six underpasses (34–41 m wide, 5–12 m high and 53–128 m long) were monitored for an average 4.7 (2.5–5.5) years using animal-triggered multi-camera video surveillance.

    (Summarised by: Rebecca K. Smith)

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