Abstract Black bears ( Ursus americanus ) capitalize on dense calorie patches on the landscape to meet nutritional needs. Bird feeders provide a food source that is widely available and high in calories. Nearly half of all the attractant‐related bear complaints to the Minnesota Department of Natural Resources (MN DNR) are about bird feeders. While a solution is to remove the bird feeder, callers are often reluctant to do so. The MN DNR wanted to explore alternative solutions to protect bird feeders from bear damage. We created a matched‐pair study design, where each site had a bird feeder that was protected by an energized fence with >7,500 V and a bird feeder that was outside of the energized fence. We used logistic linear mixed models to estimate the probability of bears damaging bird feeders in relation to the use of energized fencing. During the first season, energized fencing was 100% effective at protecting bird feeders from bears. Of the sites that had a bear visit ( n = 7 of 14), none of the bird feeders inside the energized fence were damaged. During the second year, 14 of 22 sites had a bear visit, and 5 fences were breached by bears. Overall, energized fences reduced the probability of bear damage from 49% (90% CI = 39%–60%) to 4% (90% CI = 2%–38%), a proportion reduction of 92%, after accounting for food conditions and the persistence of bears trying to breach the fences. Fences were breached as a result of grounding issues (e.g., shorting fence on itself, tipped over energizer, and grounding spike out of the soil). While not a perfect solution, energized fencing was an effective tool to protect bird feeders from bears.
Leeper et al. (Wed,) studied this question.