Damage Prevention and Control Methods

Exclusion

Grizzly/brown bear, Ursus arctos

The challenges of exclusion are formidable. Bears are incredibly adept at problem solving where food is concerned, no doubt as a result of their extreme orientation to food for a few short months. Brown bears will expend a great amount of energy and time digging under, breaking down, or crawling over barriers to food. They know how to use their great weight and strength to open containers. They will chew metal cans “like bubble gum” to extract the food.

To exclude bears, use heavy, chain-link or woven-wire fencing at least 8 feet (2.4 m) high and buried 2 feet (0.6 m) below ground. Install metal bar extensions at an outward angle to the top of the fence and attach barbed wire or electrified smooth wire. Also consider attaching an electrified outrigger wire to the fence.

Electric fencing is also very effective if built correctly. At a minimum, 12-gauge, high-tensile fencing should be used—nine wires high, spaced 6 inches (15 cm) at the top and 4 inches (10 cm) at the bottom, with alternating hot and ground wires. Both the top and bottom wires should be hot. Use a low-impedance charger with a minimum output of 5,000 volts.

In backcountry situations, an electric fence perimeter may be the only sure protection from grizzly/brown bear damage. Secure the camp, supplies, and livestock within the confined area. In the absence of fencing, bear-proof containers provide the best protection for food and other supplies. Use 45-gallon (200-l) oil drums with locking lids to secure all bear attractants. Backpackers in bear country should use portable bear-proof containers. Attractants (food, meat, feed) can also be hung in an elaborate, bear-proof manner, at least 20 feet (6.5 m) above ground, and free from any aerial approach. Tower caches, 20 feet high or higher, can also be constructed using heavy poles and timbers.

Cultural Methods

Once a bear has developed a detrimental behavior, it may be impossible to change it. Prevention is directed mostly at keeping the bear population wild and fearful of people. If the mothers teach their young to avoid humans, problems will be minimal, though not nonexistent. Hunting pressure automatically teaches bears to avoid humans.

Choose campsites, bee yards, and livestock bedding sites in areas not frequented by bears. Avoid riparian areas, rough ground, heavy cover, aspen groves, and berry-covered hillsides. In spring and early summer, bears frequent riparian areas, low-elevation flood plains, hillside parks, and alluvial fans where high protein grasses, sedges, and forbs are plentiful. In late June or early July, bears turn to areas with berries and other high-energy foods. Often, livestock need to be held out of such areas only an extra 2 weeks, until the bears turn to other foods. In areas with a history of bear problems, livestock should be confined in buildings or pens that are at least 50 yards (50 m) from wooded areas and protective cover, especially during the lambing or calving season. Remove carcasses from the site and dispose of them by rendering or deep burial.

Bears should never be fed or intentionally given access to food scraps or garbage. Eliminate all sources of human foods around campsites, cabins, restaurants, and suburban areas. Keep garbage in clean and tightly sealed metal or plastic containers. Spray garbage cans and dumpsters regularly with disinfectants to reduce odors. Maintain regular garbage pickup schedules and bury or burn all garbage at fenced sanitary landfills.

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Frightening Devices

Boat horns, cracker shells, rifle shots, and other loud noises may frighten bears from an area. Roaring engines and helicopter chases may also be effective. Barking dogs can be very useful, but they must be trained to bark on sight or smell of a bear. In addition, good bear dogs will chase bears, but they must be trained to pursue and corner without closing on the bear. Lights and strobe flashes are only marginally effective for bear damage prevention.

Repellents and Deterrents

Capsaicin spray has been reported to be an effective repellent. It may work only once, however, so a backup deter-rent should always be available.

Well-trained dogs can provide an “early warning system” as well as a deterrence to bears. Unfortunately, not many trained dogs are available in the United States or Canada. Plastic slugs may also be an effective deterrent against bears. Bears usually move rapidly to the nearest cover when frightened, so care must be taken to avoid being positioned between the bear and escape cover.

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Trapping

The capture and translocation of bears can be effective in damage control. Unfortunately, relocation often only moves the problem to another site, and bears have been known to travel great distances to return to a trapping site. The handling process, if done correctly, is itself sufficiently traumatic to teach the bears to avoid humans. Use culvert traps or foot snares to capture bears. Care must be taken in baiting to avoid conditioning bears to people— use only natural scents and baits such as wild animal road kills. Only properly trained personnel should be assigned to such work. The Ursid Research Center in Missoula, Montana, offers courses in capturing and handling bears. Consult state regulations and wildlife agency personnel before implementing any bear-trapping program.

Immobilizing and Handling

Bears are occasionally captured by injection with an immobilizing drug administered from a syringe dart fired from a capture gun. Bears have been successfully immobilized with darts fired from close range. Bears can be approached on foot, from vehicles, and from helicopters. The drugs most commonly used include a mixture of ketamine hydrochloride and xylazine hydrochloride (Ketaset-Rompun). This mixture has a high therapeutic index and results in little distress to the animal.

The drugs chosen, the degree of sanitation, the approach to the set, the weapons carried, and the size of capture crews are extremely crucial in tending the animal. Interning with a recognized expert, or attending a certified course should be required before attempting to capture brown bears.

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Shooting

Many grizzlies have been killed in response to livestock depredations, as allowed under the US Endangered Species Act. Over time, public tolerance for this approach has declined and fewer bears are now being killed or removed. Currently, shooting is used most often on adult males, since they are not considered essential in a population. This may, however, be short-sighted, considering that all other bears in an area modify their own behavior based on the activities of the dominant adult male bear. Left alone, a bear often will not kill livestock again, or could be trained through aversive conditioning not to attack livestock.

Firearms should be carried by people working with bears or in areas where the risk of bear attack is high. The best protective weapons are high-powered rifles of .350 caliber or larger and 12-gauge pump shotguns with rifled slugs. Handguns (.44 magnum) should be carried for quick defense only.

Aversive Conditioning

Aversive conditioning may be effective in teaching bears to fear humans. In Montana, problem bears were captured and brought into holding facilities where they were repeatedly confronted by humans and repelled with chemical sprays. Treatment was complete when the bear fled instantly to the “sanctuary” portion of an enclosure. The bear was then quickly returned to the wild. The captive process, called “bear school,” lasts only 4 to 6 days. This method can only be conducted by fully trained personnel. Field treatment may follow, using radio collars, 24-hour monitoring, and firearm backup. Aversive conditioning may cost up to $6,000 per animal, but it may be cost-effective, considering the alternatives.

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Public Education

Public attitudes are crucial in determining what damage prevention or control is practical. The State of Montana now has two staff members authorized to work closely with people in grizzly range not only to solve bear problems but to meet with the public and listen to their concerns. They talk in schools and at rural functions and work with individual ranchers to solve special problems or help in emergencies.

Avoiding Human-Bear Conflicts

Preventing Bear Attack. Grizzly/brown bears must be respected. They have great strength and agility, and will defend themselves, their young, and their territories if they feel threatened. They are unpredictable and can inflict serious injury. NEVER feed or approach a bear.

To avoid a bear encounter, stay alert and think ahead. Always hike in a group. Carry noisemakers such as bells or cans containing stones. Most bears will leave a vicinity if they are aware of a human presence. Remember that noisemakers may not be effective in dense brush and near rushing water. Be especially alert when traveling into the wind since bears may not pick up your scent and may be unaware of your approach. Stay in the open and avoid food sources such as berry patches and carcass remains. Bears may feel threatened if surprised.

Watch for bear sign—fresh tracks, digging, and scats. Detour around the area if bears or their fresh sign are observed.

NEVER approach a bear cub. Adult female brown bears are very defensive and may be aggressive, making threatening gestures (laying ears back, huffing, chopping jaws, stomping feet) and possibly making bluff charges. Bears have a tolerance range which, when encroached upon, may trigger an attack. Keep a distance of at least 100 yards (100 m) between you and bears.

Bears are omnivorous, eating both vegetable and animal matter, so don’t encourage bears by leaving food or garbage around camp. When bears associate food with humans, they may lose their fear of humans. Food-conditioned bears are very dangerous.

In established campgrounds, keep your campsite clean and lock food in the trunk of your vehicle. Don’t leave dirty utensils around the campsite, and don’t cook or eat in tents. After eating, place garbage in containers provided at the campground.

In the backcountry, establish camps away from animal or walking trails, and near large, sparsely branched trees that can be climbed should it become necessary. Choose another area if fresh bear sign is present. Cache food away from your tent, preferably suspended from a tree that is 100 yards (100 m) downwind of camp. Use bear-proof or airtight containers for storing food and other attractants. Freeze-dried foods are lightweight and relatively odor-free. Pack out all noncombustible garbage. Always have radio communication and emergency transportation available at remote base or work camps in case of accidents or medical emergencies.

Don’t take dogs into the backcountry. The sight or smell of a dog may attract a bear and stimulate an attack. Most dogs are no match for a bear. When in trouble, the dog may come running back to the owner with the bear in pursuit. Trained guarding dogs are an exception and may be very useful in detecting and chasing away bears in the immediate area.

Bear Confrontations. If a brown bear is seen at a distance, make a wide detour. Keep upwind if possible so the bear can pick up human scent and recognize human presence. If a detour or retreat is not possible, wait until the bear moves away from the path. Always leave an escape route and never harass a bear.

If a brown bear is encountered at close range, keep calm and assess the situation. A bear rearing on its hind legs is not always aggressive. If it moves its head from side to side it may only be trying to pick up scent and focus its eyes. Remain still and speak in low tones. This may indicate to the animal that there is no threat. Assess the surroundings before taking action. There is no guaranteed life-saving method of handling an aggressive bear, but some behavior patterns have proven more successful than others.

Do not run. Most bears can run as fast as a racehorse, covering 30 to 40 feet (9 to 12 m) per second. Quick, jerky movements can trigger an attack. If an aggressive bear is met in a wooded area, speak softly and back slowly toward a tree. Climb a good distance up the tree. Adult grizzlies don’t climb as a rule, but large ones can reach up to 10 feet (3 m). Defend yourself in a tree with branches or a boot heel if necessary.

Occasionally, bears will bluff by charging within a few yards (m) of an unfortunate hiker. Sometime they charge and veer away at the last second. If you are charged, attempt to stand your ground. The bear may perceive you as a greater threat than it is willing to tackle and may leave the area. As a last resort when attacked by a grizzly/brown bear, passively resist by playing dead. Drop to the ground face down, lift your legs up to your chest, and clasp both hands over the back of your neck. Wearing a pack will shield your body. Brown bears have been known to inflict only minor injuries under these circumstances. It takes courage to lie still and quiet, but resistance is usually useless.

Many people who work in or frequent bear habitat carry firearms for personal protection. Although not a popular solution, it is justifiable to kill a bear that is attacking a human.