A Silver-Tipped Grizzly Bear or a
Blond Black Bear?

A Guide to Identifying a Bruin

By Steve Gehman

Is it a black bear or a grizzly bear? I hear that question fairly often when I am leading natural history tours, teaching field ecology courses, and otherwise watching bears with other wildlife enthusiasts. The challenge of correctly identifying these two bear species may arise whenever you venture into areas where the species exist together in the northern Rocky Mountains of western Wyoming, western Montana and northern Idaho, the North Cascade Mountains of Washington, southern portions of Alaska and the Canadian provinces of Alberta and British Columbia.

Unfortunately, the common names applied to these two bear species are not accurate descriptors, and frequently lead to confusion. For example, black bears (Ursus americanus) are not always black. The proportion of black colored bears in a population of black bears varies considerably among regions of North America, with generally fewer black individuals in western populations than in eastern ones. Black bears may also be blond, reddish or cinnamon, brown, white (Kermodes phase, found along the coast of British Columbia), or "blue" (glacier bear, found in glacial areas of southeastern Alaska). Therefore, "black bear" is not a very appropriate name for the species, and color is not a very good characteristic to use in identifying bear species.

To add further to the confusion, we have the term "brown bear" with which to contend. In some eastern states, people use the term "brown bear" in reference to brown or cinnamon color phase individuals of the black bear species; while in Alaska and Canada, brown bear refers to coastal-dwelling members of the grizzly bear species (Ursus arctos).

Like black bears, grizzly bears come in many colors; blond, reddish, many shades of brown, gray and black. In the Yellowstone Ecosystem, approximately 60-70 percent of grizzly bears have the grizzled, or silvertip color pattern, created by a coat of brown guard hairs with silver, white or blond tips.

If all of this sounds confusing, just be glad that you weren't trying to identify bears during the 1800s and early 1900s, when taxonomists classified 43 species of bears in North America, based primarily upon color and size characteristics.

Speaking of size, it also is a relatively poor characteristic to use in identifying bear species. In areas where both black and grizzly bears occur, the average size of grizzly bears is generally greater than that of black bears; however, enough variation in size exists among bears of both species to prevent size from being a definitive characteristic. Furthermore, it can be extremely difficult to accurately estimate the size or weight of a bear in the field, when looking through binoculars or spotting scopes from a great distance.

If we can't use color or size to distinguish bear species, what can we use? Luckily, there is a series of field characteristics that make it possible to distinguish black from grizzly bears in most cases. The first thing that I typically look for is the presence or absence of a hump, or large muscle mass located above the bear's shoulders at the base of its neck; grizzly bears have humps, black bears don't. However, some grizzly bears have smaller, less obvious humps, which may be difficult to detect, especially if those bears have long, thick coats of hair; and some black bears look like they have humps, if they are standing with their front feet higher than their rear feet, with their necks outstretched and their noses to the ground.

On to the next characteristic is overall body shape. If you get a good profile of the bear and if it is standing on relatively level ground, you can use the following general rule: a black bear's rump, or hindquarters, will be more massive than its forequarters, and its body will appear to be tapered somewhat from tail to nose; a grizzly bear's forequarters will be more massive than its hindquarters, and its body will be somewhat tapered from shoulders to rump.

Some people talk about using the dish-shaped, or concave skull profile of the grizzly bear to distinguish it from the convex, or Roman-nose profile of the black bear, but I do not find these characteristics to be very user-friendly in the field, especially from great distances. What I have found to be useful instead is ear size relative to head size: black bear ears appear significantly longer relative to head size than do grizzly bear ears.

If you are viewing a bear standing on bare soil, standing in a clear body of water, or standing upright on its hind legs, you may be able to use the claws on its front feet to help determine species. Black bears have relatively short (1-1.5"), black, heavily curved claws, whereas grizzly bears have longer (2-4") claws that are generally light colored and only slightly curved.

 Differences in claws translate into some key behavioral differences between black and grizzly bears that may be useful in species determinations. The black bear's short, heavily curved claws make it an exceptional tree climber. Black bears frequently climb trees to avoid confrontations with other bears, and as an escape from humans, dogs, or other predators. On several occasions in Yellowstone National Park, I have observed black bears climb trees in response to approaches by wolves, after bears wandered too close to a wolf den site or a wolf-killed elk. Similarly, mother black bears commonly send their cubs up a tree at the first sign of potential danger.

Probably the most common myth that I hear regarding bears is that grizzly bears cannot climb trees. The truth is that grizzly bears can climb trees, but do so much less frequently than do black bears. I once saw a three-year-old Kodiak bear climb up 30 feet into a large cottonwood tree to avoid another bear. I have also seen Tim Manley's photographs of grizzly bears in trees, obtained during a research project in the South of the Flathead River drainage in northwestern Montana. I would say, however, that black bears are much more skillful and graceful climbers than are grizzly bears, and that if you see a bear moving easily up and down a tree, chances are good that it is a black bear.

The grizzly bear's long claws and well developed shoulder musculature make it a much better digger than the black bear. During late summer and fall, some grizzly bears spend many hours digging for roots of plants such as spring beauty, biscuitroot, and glacier lily. While hiking through mountain meadows, you may find areas the size of your living room (or larger) torn up by bears harvesting such delicacies. Black bears are not as well equipped for digging, and therefore make much less use of root crops as a food source than do grizzlies. Both bear species use their claws to rip open decaying logs and tree stumps to feed on insects, and evidence of such activity is common throughout forests inhabited by bears.

 One final behavioral idiosyncrasy to be aware of is the tendency among black bears to use forested habitat or meadow habitat near a forest edge. This seems to be particularly true in areas where black bears live among grizzlies. Forests provide more hiding cover than open areas and greater escape options (i.e. trees to climb) in the event of an encounter with a grizzly bear. In the northern portion of Yellowstone National Park, grizzly bears are commonly observed more than several yards from a forest edge, but black bears are not.

As you head out into bear country, be alert and observant, and keep these distinguishing characteristics in mind. Happy bear viewing.