A novel bipolar electric fence for excluding white-tailed deer from stored livestock feed1

Where cattle (Bos taurus) and free-ranging white-tailed deer (Odocoileus virginianus) coexist, they frequently share space and resources, potentially resulting in damage to stores of livestock feed and risk of interspecies disease transmission. Preventing use of stored feed by deer can be an important objective in farm management, depending on amount of damage experienced and perceived risk of disease transmission. Woven wire fences (2.4 to 3.0 m high) are generally considered to be the most effective means for excluding deer. However, rapidly deployable temporary means of excluding deer could be useful, especially during late winter when deer are most physiologically stressed and motivated to consume feed meant for cattle. Thus, the objective of this study was to evaluate a novel 1.2-m-tall electric fence consisting of 4 strands of bipolar tape (not requiring separate ground wires or animal contact with ground) for excluding deer from artificially established feed piles during late winter 2008 in northwestern Minnesota. To induce deer to pause, investigate the fence, and receive negative stimuli before attempting to jump the fence, the bipolar tape was baited with a viscous fluid attractive to deer. The fence was estimated to be >80% effective at reducing deer presence at feed piles (10 treatment sites and 11 control sites) given the late winter to early spring conditions. Despite the efficacy, using the fence as a primary means of protecting stored feed from deer in areas with known disease transmission risk (e.g., presence of bovine tuberculosis) is not recommended because risk could remain unacceptably high if even low numbers of deer access stored feed. Yet, the fence could be effective as immediate protection of stored feed in winter before a more permanent and effective deterrence strategy, such as woven-wire fencing, could be installed during the subsequent summer. The fence would also be effective for reducing deer depredation of stored feed, as well as gardens, small orchards, or other localized or seasonal resources.