Yellowstone Grizzly Bear
Yellowstone's apex omnivore — spring meadows, fall hyperphagia.
Overview
Grizzly bears (Ursus arctos horribilis) are large, long-snouted brown bears with a distinctive shoulder hump built for digging. They're omnivores whose diet shifts with the seasons — roots and rodents in spring, berries and moths in summer, nuts and carrion in fall.
The Greater Yellowstone Ecosystem grizzly population was listed as threatened in 1975 and has since recovered; NPS and USGS monitoring put the GYE population around 700+ bears. They're most visible in spring (foraging in lower meadows after emergence) and fall (hyperphagia, the feeding frenzy before denning).
Where to find them
- Lamar Valley: Spring meadows — grizzlies dig for roots and hunt winter-killed elk.
- Hayden Valley: River meadows and carrion; strong in spring and fall.
- Mount Washburn & Dunravan Pass: Summer grizzlies follow the green-up upslope.
- Antelope Creek: A classic summer slope-viewing area (closed to off-trail).
When to look
Two windows: spring (late April–June) as bears emerge and forage openly, and fall (September–October) during hyperphagia when they feed almost constantly. Dawn and dusk are best.
⚠️Stay at least 100 yd away
Frequently asked questions
How can I tell a grizzly from a black bear?+
Look for the grizzly's prominent shoulder hump (a muscle mass for digging), dished/convex face, and large rounded ears set wide apart. Black bears have a straighter facial profile, no shoulder hump, and taller pointed ears. Color is unreliable — black bears can be brown or blonde.
When do grizzlies come out in Yellowstone?+
Grizzlies emerge from dens in early spring. The first confirmed 2018 sighting was March 10 at LeHardy Rapids. Males emerge first, then females without cubs, and finally females with new cubs in April–May.
What is hyperphagia?+
The intense feeding period (late summer–fall) when bears consume up to 20,000 calories a day preparing for winter. They're more visible because they feed for many hours, but also more focused and protective of food sources — keep extra distance.
Are grizzly bears endangered?+
The Greater Yellowstone population was listed as threatened under the ESA in 1975 and has recovered to 700+ animals. Its legal status has shifted (delisted and relitigated), but the population itself is a conservation success story.
Sources & data notes
- Grizzly Bear data is drawn from official NPS, USGS, and NOAA sources catalogued in our source registry. Observer-submitted sightings are not published on this public guide.
- Grizzly Bear carries dedicated official data (NPS ecology / management reports).
- NPS Yellowstone grizzly bear facts — National Park Service (Official grizzly facts from Yellowstone Science; species context only.)
- NPS Yellowstone bear management page — National Park Service (Official bear-management process and BMA context; annual reports still need deeper PDF parsing.)
- NPS Yellowstone Bear Management annual reports — National Park Service (Only a small subset of available annual bear reports is currently parsed.)
- USGS IGBST Yellowstone Grizzly Bear Investigations 2024 annual report — U.S. Geological Survey (Greater Yellowstone Ecosystem grizzly report; not limited to Yellowstone National Park.)
Spotted something off, or want a deeper dive? Every claim above links to its original source — look for the ↗ markers and the Sources section.