Brown bears are found in numerous parts of the Northern Hemisphere. There are several subspecies, found in various areas of North America and Eurasia. Brown bears range in color from light brown to almost black and weigh from 500 to 1700 pounds (225 to 770 kg). They generally feed on plants, but they are good fishers and feast on the salmon that come up the northern rivers to spawn. Some brown bears can be tamed and taught to dance and do tricks.
The grizzly bear is found in the Rockies from Alaska to Colorado. It has a brownish-yellow coat with grizzled (silver-tipped) outer hairs. Grizzly bears have long, sharp claws. When cornered or wounded they are extremely dangerous; unprovoked attacks on humans have also occurred. The grizzly bear is one of several types of brown bears in danger of becoming extinct because of loss of habitat and indiscriminate hunting.
Grizzly bears are grizzled, which means “streaked with gray.” A grizzly’s underfur—the fur closest to its skin—is shaggy and mostly shades of brown. But the grizzly also has outer hairs that are white or silver-tipped. This gives the bears a “grizzly” look.
Grizzlies are big brown bears, but don’t let the word brown fool you. Although grizzlies are usually dark brown, they may be cream to almost black in color.
Most adult grizzlies can grow to 8 feet (2.4 meters) long. If one stood on its hind legs in your living room, it might hit its head on the ceiling! A male grizzly may weigh up to 500 pounds (230 kilograms)—the weight of two very large men. Female grizzlies usually weigh 350 to 400 pounds (160 to 180 kilograms). Even though they are smaller than males, female grizzlies are just as fierce—especially when protecting their young.
Very strong bones and powerful muscles are under that mass of fur. A grizzly’s skeleton is much like that of other bears.
Bears have large heads and skulls. They have powerful jaws. They have broad shoulders. A grizzly also has a hump of muscle on its shoulders. So do other big brown bears. One way to tell a big brown bear from other kinds of bears is to look for this hump.
Like other bears, a grizzly has four short legs. Just two of them can support the bear’s entire weight when it stands.
A grizzly has broad, flat paws. There are five toes on each paw. The toes have long, sharp claws that do not pull back, or retract. While most other animals walk on their tiptoes, bears walk on the soles of their feet—just as people do.
The bear’s eyes and ears are small for such a big animal. But the bear’s snout and nose are quite large. Grizzlies depend on their sense of smell to find food. Smell is a bear’s sharpest sense.
A grizzly bear can smell carrion (KAIR ee uhn), or the flesh of a dead animal, from very far away. How far away?Some scientists say that bears can smell carrion from 18 miles (29 kilometers) away.
Grizzlies are out and about during the day and at night. They seem to be most active at dusk or at dawn, however. And, in places where there are people, these bears tend to be nocturnal, or active at night.
Grizzly bears do eat meat. They eat land animals, such as elk and moose, as well as fish. But grizzlies also feed on plants. These animals also eat berries, grasses, leaves, and roots.
It takes a lot of food to fuel a grizzly bear’s body. For this reason, the bears spend most of their time foraging, or searching for food.
In summer and early fall, a grizzly may eat 80 to 90 pounds (36 to 41 kilograms) of food a day. You would have to have about 300 hamburgers a day to keep up with the bear. Later in the fall, the bear stuffs itself even more. It may gain several pounds of fat a day. The extra fat helps the bear survive the long winter, when it may eat nothing for months.
Many animals hibernate (HY buhr nayt) during the winter. During hibernation, animals go into a deep sleep. Grizzlies do go into a winter sleep—but some scientists say it is not true hibernation. During winter sleep, a grizzly can rouse itself right away if it needs to. This is especially important for female bears that may be caring for cubs.
Some grizzlies find caves or other natural shelters for their winter sleep. Others dig dens. They start digging in the fall, before the ground freezes. Often they dig into steep slopes. A den entrance is usually very narrow, but then it widens into a larger sleeping room.
Grizzly bears usually move into their winter homes between October and December. At that time of year, the plants that bears usually eat have disappeared.
A grizzly looks bare—or hairless—when it is first born. But that changes quickly. Within10 days, grizzly cubs already have some fur. The mother grizzly usually gives birth to two cubs, but she may have one to four. The cubs’ eyes are closed at first. They stay closed for about a month. The mother bear cuddles her cubs to keep them warm and safe. Grizzly cubs are quite tiny at birth. They usually weigh 12 to 24 ounces (340 to 680 grams). That’s about the size of a small gray squirrel. But the cubs grow quickly as they feed on their mother’s milk. This milk is very rich in fat—many times richer than a human mother’s milk.
Most grizzlies leave their winter dens between March and May. Mothers with new cubs, however, usually stay in their dens longer than bears without cubs. Cubs are frisky and playful when they come out of the den.
Grizzly cubs need to learn certain skills in order to survive on their own. Until then, they depend on their mother. The mother bear feeds and protects her young. If a mother grizzly dies, her cubs are likely to die also.
Cubs learn how to forage from their mother. She also teaches them how to fish. Cubs may continue to use the mother’s fishing method even after they grow up.
The cubs also learn through play. They practice chasing and stalking each other. They chew, swat, and jaw wrestle. These activities build muscles.
Grizzly cubs usually stay with their mother for the first 11/2 to 31/2 years of their lives. Then the family drifts apart. The young adults may den where their mother denned for another year or two. But then they go off on their own.
Grizzlies are loners. They live alone. They hunt alone. They feed alone. But once a year, they do have a kind of get-together. That time comes in the summer, when the streams are filled with salmon. Salmon and other fish are an important part of a grizzly’s diet.
Grizzlies use different methods to catch fish. Some grizzlies stand still in the water. They watch the fish closely. When a fish jumps out of the water, the grizzly snatches it with its jaws. Other grizzlies swat the fish out of the water and up onto the shore.
Some grizzlies dive or “snorkel” under the water in order to find fish. Sometimes a bear launches itself onto the salmon in a bellyflop.
Grizzlies don’t communicate much. Or, if they do, we don’t know a lot about how they do it. But scientists think that these bears do signal each other.
One way that a grizzly signals another bear is by showing off its size. A small bear will usually run from a bigger bear. Two bears that are the same size may circle each other. An angry grizzly will signal by lowering its head and flattening its ears. The bear may even growl or snort.
Some grizzlies stretch up tall and use their claws to scratch the bark of trees. This leaves behind the grizzly’s scent. Its scent lets other bears know that the grizzly is around. This may keep grizzlies from running into each other and probably prevents fights.
The Kodiak bear, found on Kodiak Island off the coast of Alaska, is the largest living carnivore. Kermode's bear inhabits the northwest coast of British Columbia. It is almost completely white.
In England, where they are now extinct, brown bears were often victims of a cruel sport called bearbaiting. A bear chained to a stake in a public place would be forced to fight a pack of dogs. Bearbaiting was outlawed in 1853.
Like grizzlies, Kodiaks are big brown bears. But Kodiaks are even bigger than grizzlies. A Kodiak can stand 9 to 10 feet (2.7 to 3.0 meters) tall. In the fall, a Kodiak can weigh around 1,500 pounds (680 kilograms).
Like their grizzly cousins, Kodiaks love salmon. And there are many salmon where the bears live—on and around Kodiak Island. Kodiak Island, which is off the coast of Alaska, is a salmon spawning ground. A spawning ground is a place where fish lay eggs and breed. It’s also a great place for bears to find their favorite foods.
Kodiaks are excellent fishers. A mother can catch 15 salmon in an hour to feed herself and her cubs. Kodiaks also feed on beached whales.