# Grizzly Bear — Facts, Threats & Conservation

*Ursus arctos horribilis (Ord, 1815)*

> The grizzly bear (Ursus arctos horribilis) is a North American brown bear subspecies; the brown bear is Least Concern globally, but grizzlies in the contiguous United States are protected under the Endangered Species Act with roughly 1,900 individuals south of Canada.

**IUCN status:** Least Concern brown bear; threatened in parts of USA  ·  **WARN range:** Western Canada, Alaska, North-western United States

## Quick facts
| Fact | Value |
| --- | --- |
| Weight | 180–360 kg (males); females ~90–200 kg |
| Distinctive feature | Shoulder hump; silver-tipped fur |
| Diet | Omnivorous — plants, fish, rodents, ungulates |
| Hibernation | Pregnant females den; torpor over winter |
| Lifespan | Up to ~25 years in the wild |
| CITES | Appendix II (most populations) |

## Scientific classification
- **Kingdom:** Animalia
- **Phylum:** Chordata
- **Class:** Mammalia
- **Order:** Carnivora
- **Family:** Ursidae
- **Species:** Ursus arctos (Linnaeus, 1758)
- **Subspecies:** Ursus arctos horribilis (Ord, 1815)

## Conservation status
- **Status:** Brown bear Least Concern globally (IUCN, 2016). Grizzly in lower 48 US states listed as threatened under Endangered Species Act.
- **Population:** ~1,900 in contiguous USA; 30,000+ in Alaska; large populations in Canada and Russia
- **Trend:** Increasing in lower 48 USA; stable in Alaska and Canada
- **Assessed:** 2016 (brown bear species)
- **CITES:** Appendix II (most populations)

## Key facts: Grizzly Bear
- Grizzlies are a subspecies of brown bear — Ursus arctos horribilis.
- The shoulder hump of muscle distinguishes grizzlies from black bears.
- Grizzlies are omnivores, eating plants, fish, rodents and ungulates.
- They once ranged across western North America but now occupy ~2% of historic US range.
- Alaska and Canada hold the largest remaining grizzly populations.
- Human conflict and habitat fragmentation are the main threats in the lower 48 states.

## Grizzly or brown bear?
Taxonomists classify the grizzly as Ursus arctos horribilis — a subspecies of the brown bear (Ursus arctos), which also includes the Eurasian brown bear, Kodiak bear and Alaskan coastal brown bear. Coastal brown bears in Alaska grow larger than interior grizzlies because of abundant salmon. The name 'grizzly' refers to the grey-tipped guard hairs that give the coat a frosted appearance, though fur colour ranges from nearly blonde to dark brown.

The prominent shoulder hump — a mass of muscle for digging — and a dished facial profile distinguish grizzlies from American black bears, which lack the hump and have a straighter nose profile.

## Ecology and diet
Grizzlies are among the most omnivorous of bears. Spring diet includes emerging plants, roots and carrion from winter-killed ungulates. Summer brings berries, ants and grubs.

Where salmon run, coastal grizzlies gather at rivers to catch fish — a caloric bonanza that supports large body size. Grizzlies also prey on moose calves, elk calves and ground squirrels. They disperse seeds through scat and enrich soil by digging for roots. Home ranges vary from roughly 70 km² for females to over 1,000 km² for males in interior habitats. Dens are dug into slopes; pregnant females enter torpor over winter, giving birth in the den.

## Grizzlies and people
Grizzly encounters capture public attention because of the potential for injury, yet attacks are rare and usually involve surprise encounters, food-conditioned bears or mothers defending cubs. Bear spray is more effective than firearms in deterring charges. In Yellowstone and Glacier national parks, millions of visitors coexist with grizzlies through food-storage rules, trail closures and education. Outside parks, livestock depredation and game-hunting competition create conflict with ranchers and hunters. Relocation and aversive conditioning reduce problem behaviour. In Alaska and Canada, regulated hunting is permitted under management plans.

## Conservation status
The brown bear is Least Concern globally with an estimated 200,000 individuals, mostly in Russia, Alaska and Canada. Grizzlies in the contiguous United States were listed as threatened under the Endangered Species Act in 1975; the population has recovered from roughly 700–800 to about 1,900, leading to repeated delisting debates. Connectivity between the Yellowstone, Northern Continental Divide and Cabinet-Yaak ecosystems remains a conservation priority. CITES Appendix II regulates international trade. Protecting large connected landscapes and reducing attractants near human settlement are essential for long-term grizzly persistence south of Canada.

## Related WARN guides
Grizzly bears are brown bears — read WARN's polar bear guide for Arctic Ursids, black bear page for American cousins, and wolf guide for shared wilderness habitat.

Cougar and lynx pages cover other large carnivores in bear range.

Conflict reduction and corridor protection keep grizzlies on recovery paths.

## What WARN does
WARN publishes this grizzly bear guide as free public education. Large carnivore recovery in North America shows what is possible when hunting is regulated and habitat is protected — lessons relevant to bear conservation worldwide.

If this guide helps you understand wildlife and the pressures it faces, a gift to WARN supports habitat protection and free public education in our partner countries.

## Frequently asked questions: Grizzly Bear
### What is the difference between a grizzly bear and a brown bear?
The grizzly is a subspecies of brown bear (Ursus arctos horribilis) found in interior North America. Coastal Alaskan brown bears are the same species but grow larger due to salmon-rich diets. 'Grizzly' refers to the silver-tipped fur.

### How can you tell a grizzly from a black bear?
Grizzlies have a prominent shoulder hump, a dished facial profile and longer, curved claws. Black bears lack the hump, have a straighter nose profile and shorter claws. Fur colour alone is unreliable — both species vary from blonde to black.

### Are grizzly bears endangered?
Brown bears are Least Concern globally. Grizzlies in the contiguous United States are protected as threatened under the Endangered Species Act, with roughly 1,900 individuals. Alaska and Canada hold much larger populations.

### What do grizzly bears eat?
Grizzlies are omnivores eating berries, roots, grasses, ants, fish (especially salmon), rodents, carrion and ungulate calves. Diet varies seasonally and by region.

### How many grizzly bears are left?
Roughly 1,900 grizzlies survive in the lower 48 United States. Alaska may hold 30,000 or more brown bears, and Canada hosts large populations in British Columbia and the territories.

### Are grizzly bear attacks common?
No. Grizzly attacks are rare relative to visitor numbers in bear country. Most involve surprise encounters, food-conditioned bears or mothers with cubs. Bear spray, making noise on trails and storing food properly greatly reduce risk.

## Sources
- [IUCN Red List — Ursus arctos](https://www.iucnredlist.org/species/41688/121229971)
- [U.S. Fish and Wildlife Service — grizzly bear](https://www.fws.gov/species/grizzly-bear-ursus-arctos-horribilis)
- [CITES — Checklist of CITES Species](https://checklist.cites.org/)

---
Full guide: https://worldanimalrescuenetwork.org/wildlife-guides/grizzly-bear