Under the right conditions, electric bear fences can be a great tool for campers, backpackers, kayakers or hunters. They are also good for keeping bears away from bee hives, food caches, smoke houses and field camps. Wildlife biologist Tim Peltier was grateful for his fence the day he heard a "pop" while he was cooking dinner at his campsite and turned around to see a bear running away. He hadn't heard the bear sneaking into the campsite from behind him, attracted by the food smells [source: Woodford].
Engineers first developed electric bear fences in the 1930s. The first bear fences were cumbersome to move, but modern versions are much more portable; some handy models fit easily into a backpack. One larger electric bear fence is powered by a 12-volt car battery and a solar charger, while some smaller fences weigh only a few pounds and use 2 D-cell batteries [source: Woodford].
Bear fences come with an energizer, fence poles, a grounding rod and connectors, fencing line, a volt meter and an alarm. They work by giving the bear a short, intense shock when it touches the fence [source: National Park Service]. The shock is not strong enough to hurt the bear, but bears, like people, don't like to be shocked. Researcher John Gookin says that, when a bear touches an electric bear fence, it "cries like a baby and runs away," and will stay away from the fence after that [source: Woodford]. A properly used electric bear fence is a good way to teach curious bears to stay away from your campsite.
To use a bear fence the right way, you need to set it up well. Clear all vegetation away from the bottom wire, and make sure the fence has a good ground -- you can check with the voltage meter to make sure. Remember to turn the fence on and shut the gate, and handle the equipment carefully to make sure you don't break any of the more delicate parts [source: National Park Service].
Conditions can affect how well an electric bear fence works. The ground wires work best in damp ground, and don't work well in sand or gravel. Rain and damp snow can interfere with the fence's effectiveness, and the fence works only as long as its batteries do [source: Woodford].
The National Park Service warns that electric bear fences are not foolproof. A bear that is being chased by another bear can easily break through the fence. They also warn that the fence is never a replacement for clean campsite maintenance and proper food handling, since a bear that is hungry enough might ignore the shock if the temptation is strong [source: National Park Service]. But using an electric bear fence along with good bear country etiquette is a great way to keep large, furry uninvited guests away from your campsite.
For more information on bear protection and other wilderness survival tips, follow the links below.
Related HowStuffWorks Articles
- Alaska Department of Fish and Game. "The essentials for traveling in bear country." Division of Wildlife Conservation. Web. 9 Dec 2009. http://www.wc.adfg.state.ak.us/index.cfm?adfg=bears.bearfax
- Gunther, Kerry et al. "Grizzly bear-human conflicts in the Greater Yellowstone ecosystem, 1992-2000." Ursus 15.1 (2004): 10-22. Web. 7 Dec 2009.http://www.bearbiology.com/fileadmin/tpl/Downloads/URSUS/Vol_15_1/Gunther_Haroldson_15_1_.pdf
- Herrero, Stephen. Bear Attacks: Their Causes and Avoidance. 2002. Print.
- Jope, Katherine, and Bo Shelby. "Hiker behavior and the outcome of interactions with grizzly bears." Leisure Sciences 6.3 (1984): 257-70. Web. 8 Dec 2009. http://www.informaworld.com/smpp/content=a913128883&db=all
- Lynch, Peter. "Project Grizzly" (1996) starring Troy Hurtubise.
- Manning, Elizabeth. "Are bear bells worth a jingle?" Alaska.com (2009). Web. 09 Dec 2009. http://www.alaska.com/bears/story/1944.html
- National Park Service. "Bears and food storage while backpacking." Yosemite National Park. Web. 16 Dec 2009. http://www.nps.gov/yose/planyourvisit/bearcanisters.htm
- National Park Service. "Bear management." Nature and Science. Web. 8 Dec 2009. http://www.nps.gov/archive/seki/snrm/wildlife/food_storage.htm
- National Park Service. "Electric fences in bear country." Web. 8 Dec 2009. http://www.nps.gov/kefj/parkmgmt/upload/Electric%20Fences%20in%20Bear%20Country%20s.pdf
- National Park Service. "Firearms for personal protection." Alaska Public Lands Information Centers. Web. 15 Dec 2009. http://www.nps.gov/aplic/firearms.pdf
- Rogers, Lynn. "Reactions of free-ranging black bears to capsaicin spray repellent." Wildlife Society Bulletin 12.1 (1984): 59-61. Web. 9 Dec 2009.http://www.jstor.org/pss/3781506
- Self Defense Products. "Pepper spray." Web. 10 Dec 2009.http://www.selfdefenseproducts.com/Pepper-Spray-p-1-c-249.html
- Sierra Interagency Black Bear Group. "Clever tricks black bears will perform to get your food." Food storage. http://www.sierrawildbear.gov/foodstorage/index.htm
- Smith, Tom, and Stephen Herrero. "A century of bear-human conflict in Alaska: analyses and implications." Brown and black bear projects. 31 May 2007. Alaska Science Center - Biological Science Office, Web. 10 Dec 2009. http://www.absc.usgs.gov/research/brownbears/attacks/bear-human_conflicts.htm
- Smith, Tom, Stephen Herrero, Terry Debruyn, and James Wilder. "Efficacy of bear deterrent spray in Alaska." Journal of Wildlife Management 72.3 (2008): 640-45. Web. 9 Dec 2009.http://www.polarbearsinternational.org/rsrc/scientists/bear_spray.pdf
- Spencer, Rocky, Richard Beausoleil, and Donald Martorello. "How agencies respond to human-black bear conflicts: a survey of." Ursus 18.2 (2007): 217-29. Web. 6 Dec 2009. http://www.bearbiology.com/fileadmin/tpl/Downloads/URSUS/Vol_18/Ursus_18_2_Spencer_et_al.pdf
- UDAP. "Bear spray specifications." Pepper Power Bear Spray. 23 Nov 1999. Web. 8 Dec 2009. http://www.udap.com/Bearspecifications.htm
- Windell, Keith. "Bear-resistant containers for rafters." USDA Forest Service. Aug 2006. Web. 8 Dec 2009. http://www.fs.fed.us/t-d/pubs/htmlpubs/htm06232307/index.htm>
- Woodford, Riley. "Shocking bears: electric fences for bear country campers." Alaska Fish and WildlifeNews. Alaska Division of Fish and Game. Web. 2 Dec 2009. http://www.wildlifenews.alaska.gov/index.cfm?adfg=wildlife_news.view_article&articles_id=174