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Providing evidence to improve practice

Individual study: Efficacy of an animal-activated frightening device on urban elk and mule deer

Published source details

VerCauteren K.C., Shivik J.A. & Lavelle M.J. (2005) Efficacy of an animal-activated frightening device on urban elk and mule deer. Wildlife Society Bulletin, 33, 1282-1287


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Use lights and sound to deter crop damage by mammals to reduce human-wildlife conflict Terrestrial Mammal Conservation

A replicated, randomized, paired sites, controlled study in 2001 of pastures on a ranch in Colorado, USA (VerCauteren et al. 2005) found that a device emitting lights and sound (Critter Gitter™) did not reduce combined elk Cervus canadensis and mule deer Odocoileus hemionus food consumption. Daily alfalfa consumption at bales protected by Critter Gitters™ (3.1–6.0 kg/day) did not differ from that at unprotected bales (2.8–7.3 kg/day). The Critter Gitter™ activated when infrared sensors detected movement and heat. When activated, an alarm (approaching 120 decibels) sounded for five seconds and a pair of red LEDs flashed. Five sites (>300 m apart) on private ranchland, adjacent to residential areas, were studied. Each site had two alfalfa bales, 60 m apart. One or two devices were positioned by one bale (selected randomly). The other bale was unprotected. Devices detected animals ≤2 m away. Alfalfa consumption was estimated visually, every two or three days, on 10 occasions.

(Summarised by Nick Littlewood)