- While black bears evolved in forested areas, with plenty of cover and trees to climb in case of danger, grizzlies traditionally lived in open spaces, making them less likely to flee and more likely to defend themselves by acting aggressively.
Habitat Type: Grizzly bears probably evolved in open tundra areas but now can be found as well in temperate rain forest habitats and even in open grasslands. They can be found at varying elevations from well above timber or shrub lines to river valleys far below.
Range: Within the United States, grizzlies are currently found in the mountain regions of Wyoming, Montana, Idaho and Washington near the border with British Columbia. They are found throughout western Canada and in Alaska.
Diet: Bears can eat everything people can eat and more. In interior areas more than 75 percent of their diet is vegetable matter (grass, roots, and berries) and the rest is animal matter. They eat ground squirrels, fish and insects. When they can catch them, grizzlies eat even large animals like deer, elk, moose and bison. Most commonly, however, they can only catch the newborn young of these large species.
Cubs: In January, while hibernating within their dens, between one and five cubs are born to their mothers. Most often, two cubs are born. At birth, the cubs weigh less than a pound, but they quickly put on weight and emerge from their dens in the spring weighing 10- 20 pounds. These newborns face a perilous first year; more than 50 percent of the cubs may die during this period from accidents, starvation, disease, predation and infanticide. Young grizzly cubs do their best to stay close by mother's side. If a cub accidentally gets lost, it may cry and bawl in a loud, harsh voice until its mother comes. Grizzly bear cubs have short front claws and can climb trees, unlike adults with their long front claws. Most female grizzlies are attentive parents, who tend and "discipline" their offspring and are willing, if necessary, to defend them to the death. A mother will care for her cubs typically for 2.5 years before sending them off to fend for themselves. Males do not help to care for the cubs they father.
Summer Lifestyle: Male grizzlies leave their dens in March or April but females don't leave their dens until 3-5 weeks later. Females with newborn cubs are the last to leave their dens. The exact emergence date is dependent on both climatic conditions, such as the amount of snow cover and the temperature, and physiological conditions such as the bear's age and amount of fat reserves. Once they emerge from dens, most grizzlies travel to lower elevations that have more abundant newly-emerging vegetation, carrion, and newborn hoofed animals like elk and moose. During the summer, adult bears may consume more than 50 pounds of food per day, when they can find it, and gain three to six pounds of fat each day as they replenish their depleted fat reserves and prepare for the following winter. Cubs feed from their mothers until sometime in the middle of their first summer but may continue to nurse occasionally into their second year.
Winter Lifestyle: Grizzly bears move to high elevation, remote mountain slopes that get deep, insulating winter snows. It is common for grizzlies to dig their dens on the south-facing slope of the mountain at or above the timberline. Sometimes they will den in natural caves or in a jumble or large boulders. Grizzlies enter the dens in October or November and stay there for five to six months. During this time, they live solely off of their stored fat. Grizzlies may add a third or more to their body weight to prepare for hibernations during the spring, summer and fall. They become lethargic. Grizzly bears are true hibernators and their heart rate and body temperatures drop while hibernating although not as much as some species like bats or ground squirrels which hibernate more deeply. Grizzlies can easily be awakened during hibernation. Young grizzlies den with their mothers for their first two winters. On rare occasions, young bears stay an additional year.
Hibernation: Scientists thought bears weren't true hibernators because their body temperature and respiration rate don't drop drastically as some other hibernators. But modern physiologists believe bears do hibernate; they're just relatively light hibernators compared to other deep hibernating species like ground squirrels or bats.
Breeding: Grizzly bears reach breeding maturity between four-and-a-half and five-and-a-half years, but where food is sparce, they may not reach sexual maturity until they are eight years old. The bears mate from May to July, with the peak mating time in mid-June. Embryos do not begin to develop, however, until the mother begins her winter hibernation. If the mother has not accumulated sufficient fat to sustain herself and the developing cubs, the embryo will not develop. Females typically have a new litter every three years.
Movement: The grizzly swings its head back and forth when walking slowly, but when necessary it can lope as fast as a horse. Grizzly cubs can climb as nimbly as black bear cubs, but they lose their climbing ability during their second year when their front claws grow long.
Feeding: The grizzly bear is active throughout the day and night. Omnivorous, the grizzly bear feeds on a wide variety of plant material, including roots, sprouts, leaves, berries and fungi, as well as fish, insects, large and small mammals and carrion. It is adept at catching fish with a swift snap of its huge jaws, and occasionally will pin a fish underwater with its forepaws, then thrust its head underwater to clasp the catch in its teeth. It digs insects from rotting logs or under boulders and small mammals from their burrows, sometimes tearing up much ground in the process. It caches the remains of larger mammals, such as elk, moose, or deer returning to the cache until all meat is consumed. When salmon migrate upstream to spawn, these normally solitary bears congregate along rivers and vicious fights may erupt among them. They establish dominance through size and threats, spacing themselves out, with the largest, most aggressive individuals taking the choicest stations for catching fish.
Territories: Male grizzlies range over areas of 600-1000 square miles. Females roam areas about a third as large. They can travel 20-40 miles a day if they are motivated to do so. Grizzlies do leave evidence of their presence. The most common grizzly signs are tracks, scats, dig sites, rubbing areas and day beds. Less common sites include marked trees, excavated dens and sites where large animals have been killed and cached.
Voice: Bears are commonly silent. When the need arises, however, they communicate with grunts, growels, roars or squeals (especially cubs).
Communication: Grizzlies communicate vocally with snorts, growles and roars as well as with body postures that indicate their size and status. They may popping sounds with their teeth.
Some information provided courtesy of eNature.com®.
Backcountry hiking and camping are wonderful ways to experience the out-of-doors and you may be lucky enough to see wildlife in the open. When traveling through bear country, however, it is important to follow a few rules to help ensure your own safety and that of the bears through whose homes you will be traveling.
The following tips apply to both grizzly bears and black bears, unless otherwise noted.
Before You Leave
1. Purchase a can of USDA-approved pepper spray. Make sure that it is fresh and test it before your hike to make sure that it is in proper working order. Carry it in an easily accessible place such as a belt holster while you are in bear country.
2. You may wish to read Bear Attacks, their Causes and Avoidance by Dr. Steven Herrero prior to embarking on your adventure.
Precautions to take While Hiking
1. Make your presence known. Singing, speaking loudly or making similar human-sounding noises as you hike will alert grizzly bears to your presence and help ensure that any bears in the area have sufficient time to leave to avoid encountering you.
2. While in grizzly country, hike in groups of three or more. This is another way to help ensure that bears are conscious of your presence.
3. As much as possible, stay in open areas where visibility is high. This will allow you and any bears you may encounter the maximum amount of time to react to each others' presence. Stay at least a quarter mile away from any bear you see.
4. Avoid area where there are clear signs of bears (for example, along streams where bears may be fishing, bedding sites or dens, areas with scats, or places where bear tracks are visible).
5. Be especially alert when hiking at dawn or at dusk as bears may be more active at these times.
6. Never sneak up on a bear or feed a bear in order to get a photo.
Precautions to take While Camping
1. Do not allow bears to obtain human food. Store all food (both cooked and uncooked), trash and scented items in Bear Resistant Food Containers (BRFC). These hard-plastic containers are issued free of charge with backcountry camping permits at many National Parks in the United States. The use of these containers is vital as it keeps bears from associating campsites with food.
2. When establishing your backwoods camping area, set up separate areas for sleeping and food preparation/storage. Do not burn food scraps in your fire. Instead, store them in your BRFC out of reach of bears.
3. Set up your food prep area at least 100 yards from your sleeping area. Whenever possible, suspend food containers from a tree limb out of reach of bears (at least 10 feet for grizzlies). Never cook or eat in your tent.
4. Smelling human will help the bear recognize that you are a person and do not pose a threat. Never sleep in clothes that you have worn to gut fish or clean animal carcasses. Avoid using deodorants, colognes, perfumes and other artificially scented products while camping.
What to do in Case You Encounter an Aggressive Bear
Bears usually run away when they encounter humans, but in cases when bears have been fed or otherwise habituated to humans, they may approach campers or hikers.
Actual attacks are quite rare and usually occur when the bear is startled or feels otherwise threatened.
1. If the bear does see you, let it know you are human by waving your arms above your head and speaking in a firm, even tone. This helps the bear recognize that you are calm and non-threatening. Back slowly away from the bear. If you encounter a bear while cycling, place the bike between you and the bear as you back away. Do NOT throw down your pack and do NOT run.
2. Do not behave aggressively towards the bear. Never look a bear in the eye; instead, show your deference to it by looking away.
3. If you are charged by a grizzly bear, keep your backpack on your back and curl up in fetal position with your hands behind your neck. This posture will help you protect your neck, back and belly. Play dead - do not make any sounds.
4. If you are attacked by a black bear, fight back with sticks, rocks or whatever other objects are available.
5. Use your pepper spray if a bear approaches within 10-15 feet of you. Spray the bear in the face and make sure that you are downwind of the spray.