Yellowstone Bears Hunt For Chow

Yellowstone bears are having problems finding chow. In addition to the loss of habitat by the rapid development occurring in the Yellowstone National Park ecosystem, bear researchers are concerned that several important food sources for bears are also in trouble.
Native cutthroat trout spawning in Yellowstone.

Native cutthroat trout spawning in Yellowstone

One of the most important of these is the Yellowstone cutthroat trout. Each spring, this trout runs up out of Yellowstone Lake into the tributary streams to spawn. Trout provide an important food for Yellowstone bears. But in recent years, the trout runs have been on a decline. There are a couple of reasons for this.

The first is the introduction of lake trout into Yellowstone Lake, discovered in 1994. Although no one knows how the lake trout got there, Yellowstone National Park officials don't want them. Lake trout are difficult for anglers to catch because they generally swim in much deeper water than trout. What's more, they are voracious predators and eat the native cutthroat trout like popcorn. Officials have been attempting to eliminate lake trout from the reservoir by having no limit on the catch for anglers, as well as launching an aggressive netting campaign.

Perhaps even more alarming is the fact that a deadly disease called whirling disease has made its way into the system. Whirling disease was first documented in Colorado fish hatcheries several years ago. The disease destroys the central nervous system of young fish, causing them to spin in circles, or "whirl." It is a fatal fish disease that impacts cutthroat trout. The disease can be spread through fishing equipment such as waders taken from an infected stream to a non-infected stream.

Pelican Creek, which is a major tributary, has been documented with whirling disease, and today this creek is almost devoid of Yellowstone cutthroat trout, which is not good news for Yellowstone bears.

Yellowstone National Park bears also depend upon the highly nutritious nut of the whitebark pine. This high altitude tree produces a purple pine cone loaded with pine nuts. Each fall, as the pine nuts ripen, grizzlies go into the high country to dine. Here they may stay for several weeks as they load up on the pine nuts in preparation for the winter hibernation season. Unfortunately, there is trouble on the horizon. A disease called blister rust is impacting whitebark pine, and many of these trees are dying. Scientists are looking at a number of other factors as well that may be hurting the pine, and in turn hurting the grizzly. Global warming and acid rain may also be factors.


A grizzly bear wandering among the pine trees near Swan Lake in Yellowstone

Important Food Source for Yellowstone Bears In Trouble

A history of fire suppression, rampant insect infestation, an invasive fungal plague, and global warning adds up to likely extinction for the whitebark pine.

Black bear crossing the road in Yellowstone. Photo by NPS Jim Peaco.

Yellowstone Bear Jams on Roads

When Yellowstone National Park visitors behave appropriately around roadside bears it's a positive experience for both bears and people.


Yellowstone Lake Cutthroat Trout Threatened by Non-native Lake Trout

Yellowstone National Park fisheries biologists resort to "netting" and help from anglers to save thinning population of native cutthroat trout in Yellowstone Lake.

Black bear near Indian Creek Campground in Yellowstone.

What Do Yellowstone Bears Eat?

Bears are omnivores. That means they eat both meat and plants. But bears also have seasonal needs for food based on a hibernation period.

Grizzly bear and cub.

Yellowstone Bear FAQs

Here are the answers to the difference between a grizzly and black bear, the odds of seeing a bear in the park, and if you should be afraid of bears.

Grizzly bear walking among flowering grass.

Yellowstone Grizzly Bears May Lose Protection

A proposal to delist the grizzly has sparked a national debate over the future of this endangered animal. Should we open grizzlies to hunting?

Grizzly Bear

Where to See Bears in Yellowstone

From 1980 to 2005, over 37,000 bear sightings from park visitors have been reported to park managers...

Grizzly bear in Yellowstone Park

Bear Hibernation and Reemergence in Yellowstone

When do the Yellowstone bears hibernate and when do they wake and come out of their dens? See photos and watch a video.

"Lunch Counter - For Bears Only" at Old Faithful, southeast of the upper Hamilton Store, and Ranger Naturalist Walter Phillip Martindale;

No More Lunch Counter for Yellowstone Bears

Today, it would be unheard of for people to intentionally feed bears but in the early 1900s it was common practice.