U.S. Department of Agriculture: Animal and Plant Health Inspection Service


Date of this Version



Wildlife Research, 2010, 37, 708–714; DOI: 10.1071/WR10022


Context. Wolf predation on livestock can cause economic hardship for livestock producers as well as reduce tolerance for wolves. Lethal control of wolves is often controversial; thus, development of effective non-lethal methods for reducing wolf–livestock conflict is important. Electrified fladry is a new tool that is similar to fladry (i.e. a barrier system that scares wolves), but electrified fladry also incorporates an electric shock designed to decrease the potential for wolves to habituate to the barriers.

Aim. Evaluation of electrified fladry requires understanding of its effectiveness relative to fladry and the costs and benefits of applying it in the field.

Methods. By using captive wolves, we compared the effectiveness of electrified fladry v. fladry for protecting a food resource during 2-week trials. We then performed a field trial with electrified fladry for managing wolves in Montana, USA. We measured livestock depredation and wolf activity on six treatment and six control pastures, calculated the cost of installation and maintenance, and surveyed all study participants about application of electrified fladry.

Key results. We found electrified fladry 2–10 times more effective than fladry at protecting food in captivity and that hunger increased the likelihood of wolves testing fladry barriers. In field trials, we installed 14.0 km of EF systems in treatment pastures and detected wolves twice in control pastures but never in the treatment pastures. No livestock were killed by wolves in treatment or control pastures. A completed electrified fladry system cost $2303 for the first km and $2032 for each additional km, and required 31.8 person-hours per kilometre to install. We observed 18 failures (i.e. electrified system stopped working) during a total of 394 days of use. In total, 83% of ranchers who used fladry would continue to use it under certain conditions, indicating some psychological benefit to users.

Conclusions and implications. The present study has demonstrated that electrified fladry offers superior protection compared with non-electrified fladry; however, further field tests are warranted to help determine whether benefits outweigh costs.