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Providing evidence to improve practice

Individual study: Effectiveness of highway lighting in reducing deer-vehicle accidents

Published source details

Reed D.F. & Woodard T.N. (1981) Effectiveness of highway lighting in reducing deer-vehicle accidents. The Journal of Wildlife Management, 45, 721-726


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Use road lighting to reduce vehicle collisions with mammals Terrestrial Mammal Conservation

A controlled study in 1974–1979 along a highway in Colorado, USA (Reed & Woodard 1981) found that highway lighting did not reduce vehicle collisions with mule deer Odocoileus hemionus. There was no significant difference between deer-vehicle collision rates with lights on (39 collisions from 2,611 crossings) or off (45 collisions from 2,480 crossings). Lighting did not alter the location of crossings, with accidents not occurring closer to the lights when they were off. Lighting did not alter vehicle speeds (lights on: 79 km/h; lights off: 80 km/h). Thirteen 37,000-lumen, 700-W, clear, mercury-vapour lamps (12 m high) were installed along 1.2 km of a four-lane highway (speed limit 88.5 km/h). Nine were spaced at 59–69-m intervals along 0.5 km of highway (full lighting) and two at each end were spaced at 119 and 302 m (transition lighting). Lights were alternately turned on and off for one-week periods in January–April of 1974–1979. Deer-vehicle collisions were recorded each morning and evening. Deer crossings were recorded during nightly spotlight surveys and using snow track counts. Deer behaviour was observed for two hours/night. Vehicle speeds were recorded during 35 nights in 1974.

(Summarised by Rebecca K. Smith)