Biologist sheds light on Montana black bears

With spring bear season open from April 15 through May 15 (June 15 in some areas) Montana Fish Wildlife and Parks Region 2 bear biologist Jamie Jonkel recently answered a few questions about the magnificent bruin.

Is there a reason for the color differentiation of the black bears color? Diet, or age?

Color phase is mostly related to genetics and natural selection as it relates to the habitat. That is dark timber equals dark bear colors and more open and drier country equals lighter bear colors.

Color phase can be somewhat related to diet and age. With lighter colored bears, the color of the fur can change with the season. For example, a brown phase black bear's fur maybe very dark brown when it first grows in.

But, by the fall or next spring can get quite bleached looking (from sun light and snow reflection). Some dark brown phased bears will appear black and get browner through the summer.

But, just like most black phase black bears stay black, you will get some brown or blond phased bears that stay pretty much the same all year. Some of the lighter colored bears will be very blond in early life and get darker as they age.

This may have something to do with fitness or diet - but there is just a lot of variation with individuals. And of course, because of recessive genes, you will get the occasional pied bald or albino bear.

And, regionally, you can get some odd color phases. For example, in Glacier Bay, Alaska, you have the "blue" phase or "Glacier Bear."

And in coastal British Columbia, Canada, there is the white phase, or Kermode black bear. Like with humans, there are lots of variation.

How old is a sow before she begins breeding and how often do they have more than one cub?

Black bears can have young at two years but three or four is more common. The longer they wait, the more fit they become, and the greater cub survival will be. Females quite often lose their first litter or just end up with one cub. (new mother syndrome).

Sometimes they just give birth to one cub, but the usual litter size is two to three. Most young females end up losing a cub or two. Older, more experienced matriarch females are more likely to keep all the cubs alive.

Occasionally a female will have four cubs. And females will occasionally adopt another females' cubs. That is two females with three cubs each will join up for a bit, and one female will leave with four or five cubs and the other leave with one or two.

Besides man, who else stalks black bears?

Cubs are vulnerable to most predators. The mother must be always on her toes. Male bears, grizzlies, lions, wolves, coyotes, and smaller predators will take a cub if they have the chance. Eagles will occasionally take a cub. Younger bears, yearlings, and sub adults, after leaving their mother can be vulnerable to predation. Once they reach four or five and pick up some size, they are more likely able to fend for themselves.

How does their diet change throughout the year?

When they first emerge, food is limited. They live off fat reserves and go for winter and spring carrion and spring green (grass, forbs, and roots). As spring progresses, and breeding season kicks into gear, there are more plant foods, insects, and deer fawns and elk calves available.

By late June and July, the service berry and huckleberries are ripe. Choke cherries, along the rivers, are usually ripe between August and September. Hawthorn is usually ripe between September and October.

Huckleberries ripen with elevation. In the fall months there can be some good hucks at 7,000 feet in September and October. There are lots of other berries as well: bear berry, mountain ash, snow berry, rose hip, buffalo berry, goose berry, elderberry, red ouster dog wood berry, etc.

They eat a lot of worms, grasshoppers, ants, wasps, moths, and caterpillars. They dig up lots of roots and tubers and love pine nuts and tree nuts. They are not the best hunters, but occasionally they get lucky. But they are good at scavenging other predator's kills and carrion.

Sadly, they will take advantage of unnatural food sources, such as grass, crops, bird seed, pet food, livestock feed and garbage.

If known, is climate change affecting the black bear population?

The wetter the habitat the better the habitat. So yes, global warming will reduce the quality of habitat and the density of bear populations will adjust.

Black bear hunting regulations can be found on the Montana Fish, Wildlife and Parks web site at:

2021-black-bear-final-for-web.pdf (mt.gov)