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Providing evidence to improve practice

Individual study: A shocking device for protection of concentrated food sources from black bears

Published source details

Breck S.W., Lance N. & Callahan P. (2006) A shocking device for protection of concentrated food sources from black bears. Wildlife Society Bulletin, 34, 23-26


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

Prevent mammals accessing potential wildlife food sources or denning sites to reduce nuisance behaviour and human-wildlife conflict Terrestrial Mammal Conservation

A replicated, controlled study in 2004 of 10 forest sites in Minnesota, USA (Breck et al. 2006) found that installing electric shock devices prevented American black bears Ursus americanus from accessing or damaging bird feeders. Bird feeders protected by electric shock devices suffered less bear damage (none of 10 was accessed or damaged) than did unprotected feeders (four of 10 accessed or destroyed). Two imitation bird feeders were installed at each of 10 sites, ≥30 km apart. One feeder was protected by an electric shock device, the “Nuisance Bear Controller”. This device had two 6-volt batteries wired to an automobile vibrator coil/condenser, emitting 10,000–13,000 volts through a disk when contact was made by an animal. The other feeder was unprotected. Ground around each feeder was cleared to enable identification of bear signs. Feeders were in place from 1 July to 15 November 2004. They were monitored, and bait replenished, at least weekly.

(Summarised by Rebecca F. Schoonover)

Scare or otherwise deter mammals from human-occupied areas to reduce human-wildlife conflict Terrestrial Mammal Conservation

A replicated, controlled study in 2004 of ten forest sites in Minnesota, USA (Breck et al. 2006) found that installing electric shock devices prevented American black bears Ursus americanus from accessing or damaging bird feeders. Bird feeders protected by electric shock devices suffered less bear damage (none of ten accessed or damaged) than did unprotected feeders (four of ten accessed or destroyed). Two imitation bird feeders were installed at each of ten sites, ≥30 km apart. One feeder was protected by an electric shock device, the Nuisance Bear Controller. This device had two 6-volt batteries wired to an automobile vibrator coil/condenser, emitting 10,000–13,000 volts through a disk when contact is made by an animal. The other feeder was unprotected. Ground around each feeder was cleared to enable identification of bear signs. Feeders were in place from 1 July to 15 November 2004. They were monitored, and bait replenished, at least weekly.

(Summarised by Rebecca F. Schoonover)