# Grizzly Bear (*Ursus arctos horribilis*)

> The grizzly bear is a large North American subspecies of brown bear, named for the grizzled, silver-tipped fur on its back. Grizzlies are powerful omnivores that can weigh up to 360 kg (800 lb), run as fast as 56 km/h (35 mph), and live around 20 to 25 years in the wild. They hibernate through winter in dens.

- **Category:** Mammal
- **Conservation status (IUCN):** Least Concern
- **Range:** Western North America, from Alaska down through the Rocky Mountains.
- **Canonical page:** https://globalanimalguide.org/animals/grizzly-bear/
- **Last reviewed:** 2026-07-16

## Scientific classification

- **Kingdom:** Animalia
- **Phylum:** Chordata
- **Class:** Mammalia
- **Order:** Carnivora
- **Family:** Ursidae
- **Genus:** Ursus

## Facts at a glance

| Attribute | Value |
| --- | --- |
| Scientific name | Ursus arctos horribilis |
| Diet | Omnivore |
| Habitat | Forests, meadows, and mountains |
| Lifespan | 20–25 years in the wild |
| Weight | 130–360 kg (290–800 lb) |
| Top speed | 56 km/h (35 mph) |
| Conservation status | Least Concern (IUCN) |

## Diet and feeding

Despite their fearsome reputation, grizzlies are omnivores that eat far more plants than meat. They feast on berries, roots, nuts, insects, fish, and carrion, and famously gather at rivers to catch salmon during the run. In autumn a grizzly may eat for up to 20 hours a day, packing on fat before winter.

## Hibernation

Grizzlies spend the harshest months in a den in a state of deep dormancy, living off the fat reserves they built up in autumn. Females give birth during this time, and tiny cubs nurse and grow in the den before emerging in spring. A bear's heart rate and metabolism slow dramatically while it sleeps.

## Power and the body

A grizzly is built for strength, with a distinctive shoulder hump of muscle that powers its digging and a bite strong enough to crush bone. Despite their bulk, grizzlies can sprint at 56 km/h (35 mph) over short distances, faster than any human, and they are strong swimmers and capable climbers when young.

## Conservation

Brown bears as a whole are listed as Least Concern, but grizzlies were driven out of much of their former range in the lower United States. They survive today mainly in protected areas such as Yellowstone and the northern Rockies, and recovery efforts continue to manage human-bear conflict.

## Diet and hibernation

Grizzly bears are omnivores with a hugely varied diet of berries, roots, insects, fish, and mammals. Before winter they enter a feeding frenzy called hyperphagia to build fat reserves, then hibernate for months in a den, during which females give birth to tiny cubs.

## Range and behavior

A subspecies of the brown bear, the grizzly once roamed much of western North America but is now concentrated in Alaska, western Canada, and a few areas of the northern United States. Despite their bulk, grizzlies can run up to 56 km/h (35 mph) in short bursts.

## Frequently asked questions

### What is the difference between a grizzly and a brown bear?

Grizzlies are a subspecies of brown bear. The name usually refers to inland populations, while coastal brown bears that feed heavily on salmon grow much larger.

### Do grizzly bears hibernate?

Yes. Grizzlies hibernate through winter for up to five or six months, living off the fat reserves they built up during autumn.

### What is the difference between a grizzly bear and a brown bear?

All grizzlies are brown bears, but not all brown bears are grizzlies. Grizzly refers to the inland North American subspecies, while coastal brown bears that eat more salmon grow larger. The grizzled, silver-tipped fur gives the grizzly its name.

### How fast can a grizzly bear run?

Grizzly bears can run up to about 56 km/h (35 mph) in short bursts, which is faster than the fastest human sprinter. You cannot outrun a bear, so wildlife agencies advise other safety measures instead.

### Do grizzly bears really hibernate?

Yes. Grizzlies enter a deep winter dormancy for several months, living off stored body fat without eating, drinking, or passing waste. Their body temperature and heart rate drop, and females even give birth during this period.

### How big do grizzly bears get?

Male grizzlies typically weigh 180 to 360 kg (400 to 800 lb) and stand around 2 m (6.5 ft) tall on their hind legs. Females are smaller. Coastal brown bears with rich salmon diets can grow even larger.

### What do grizzly bears eat?

Grizzlies are omnivores. Their diet is mostly plants such as berries, roots, and nuts, supplemented with insects, fish like salmon, small mammals, and carrion, depending on the season.

## Sources

- [IUCN Red List — Ursus arctos horribilis.](https://www.iucnredlist.org/search?query=Ursus%20arctos%20horribilis&searchType=species)
- [Animal Diversity Web — Ursus arctos horribilis. University of Michigan Museum of Zoology.](https://animaldiversity.org/accounts/Ursus_arctos/)
- [Wikipedia — Grizzly Bear.](https://en.wikipedia.org/wiki/Grizzly_bear)

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Source: Global Animal Guide (https://globalanimalguide.org/animals/grizzly-bear/). Licensed CC BY-NC 4.0 — free for non-commercial reuse with attribution.