Grizzly bears are a subspecies, or type, of brown bear and get their name from the white and tan tips on their brown fur that make them look “grizzled”. Though called “brown” bears, these bears can range in color from cream to almost black. Brown bears have a large hump of muscle over their shoulders and powerful claws for digging. Though their eyesight and hearing are equivalent to that of humans, they have an excellent sense of smell.
Diet: As omnivores, brown bears will eat both plant material such as roots, tubers, and fruit, and meat such as insects, carrion, rodents and other small mammals, and ungulates like deer and elk. Thanks to a diet high in fat, coastal bears in Alaska and Russia that eat salmon can become much larger than inland bears that eat more plant material. Bears are a keystone species and thus an important part of the ecosystem. When they eat fruit, their scat disperses the seeds throughout the habitat, and when they dig for roots and insects, they aerate the soil and release nitrogen for plants to use. They also help regulate prey populations.
In the Wild: Hibernation often comes to mind when people think of brown bears. Though they do retreat to dens during the winter, they are not true hibernators. During true hibernation, seen in some bats and insects, the animal’s body temperature drops drastically. This does not occur in bears, though their heart rate slows from 70 beats per minute (bpm) to 10 bpm, their metabolism slows, and they do not urinate or defecate during this deep sleep. A mother bear will even remain asleep while giving birth! By sleeping through the coldest part of the year, bears in cold climates can survive in times of food shortage. Depending on food availability, bears in warmer climates will spend less time in their winter dens, or may not use them at all.
Conservation issues/actions: Brown bears once ranged throughout the Northern Hemisphere but that range has decreased greatly. Historically, hunting was the biggest threat to bears. Today, their biggest threat is habitat loss and degradation. Climate change and unsustainable resource use have reduced bear habitat, and human population growth has brought humans much closer to bears. Bears are attracted to human areas by food left accessible to them, such as at campsites or near buildings.
At the Zoo:
The bears at Reid Park Zoo came to us because their mother was teaching them to rely on sources of food too close to humans. Their relocation was a collaborative effort between Reid Park Zoo, The US Fish and Wildlife Service, Montana Department of Fish, Wildlife, and Parks, and the Confederated Salish and Kootenai Tribes. You can help protect all bear species by not feeding them or leaving food out that is easily found by bears.