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Providing evidence to improve practice

Individual study: Evaluation of a deer-activated bioacoustic frightening device for reducing deer damage in cornfields

Published source details

Gilsdorf J.M., Hygnstrom S.E., VerCauteren K.C., Clements G.M., Blankenship E.E. & Engeman R.M. (2004) Evaluation of a deer-activated bioacoustic frightening device for reducing deer damage in cornfields. Wildlife Society Bulletin, 32, 515-523

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

Use target species distress calls or signals to deter crop damage by mammals to reduce human-wildlife conflict Terrestrial Mammal Conservation

A replicated, paired sites, controlled study in 2001 on arable fields alongside woodland at a site in Nebraska, USA (Gilsdorf et al. 2004) found that playing white-tailed deer Odocoileus virginianus distress calls did not affect deer intrusions into corn crops or subsequent corn yields. The rate of deer entries into fields was similar at fields protected by frightening devices (48–57 entried/km boundary/day) and unprotected fields (48–52 entries/km boundary/day). Similarly, there was no difference between fields before devices operated (device fields: 69 entries/km/day; unprotected: 56 entries/km/day) or after devices were turned off (device fields: 23–46 entries/km/day; unprotected: 20–47 entries/km/day). Average corn yields did not differ between fields with frightening devices (6,381 kg/ha) and unprotected fields (5,614 kg/ha). Six pairs of fields (6–20 ha, ≥0.5 km apart, matched for size, shape and location) were studied. Frightening devices played deer distress noises for 30 s when activated by deer breaking 50–200-m-long infrared beams. Two devices at each protected field covered 21–48% of the perimeter. Devices operated from 6–24 July 2001, when corn was most vulnerable to deer-damage. Deer activity was assessed by counting tracks twice during the device operating period, once five days before this and three times during 18 days after this time.

(Summarised by Nick Littlewood)