Grizzly Bear

Ursus Arctos Horriblis

Last updated: May 27, 2024
Verified by: AZ Animals Staff
© John Good - Public Domain

Less than 10% make it into adulthood


Grizzly Bear Scientific Classification

Scientific Name
Ursus Arctos Horriblis

Read our Complete Guide to Classification of Animals.

Grizzly Bear Conservation Status

Grizzly Bear Locations

Grizzly Bear Locations

Grizzly Bear Facts

Main Prey
Salmon, Fruit, Fish
Distinctive Feature
Strong, powerful shoulders and enormous claws
Forest and mountainous regions
Human, Cougars
Average Litter Size
  • Solitary
Favorite Food
Less than 10% make it into adulthood

Grizzly Bear Physical Characteristics

  • Black
  • Dark Brown
Skin Type
Top Speed
35 mph
15 - 25 years
181kg - 318kg (400lbs - 800lbs)
2.1m - 3m (7ft - 10ft)

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The Grizzly Bear–A Misunderstood Creature

The Grizzly bear is a type of brown bear that was once plentiful in the western and northwestern United States. The animal is also known as the North American Brown Bear. The name “grizzly” comes from the light tips on the bear’s fur, which gives it a grizzled or silvery appearance.

Grizzly Bear Facts

  • About 1,500 Grizzly bears live in the Lower 48 states.
  • Grizzly bears are a threatened species in the United States.
  • The California grizzly bear is extinct.
  • The grizzly-polar bear hybrid is named the ‘pizzly bear.’ In altercations that pit polar bears vs. grizzly bears, in most cases the grizzly bear has reigned supreme.

Want more grizzly bear facts? Check out ‘10 Incredible Grizzly Bear Facts.’ Here’s a preview of what you’ll discover inside, a grizzly bear’s sense of smell is 2,100 times more sensitive than a human’s!

Grizzly bear in Alaska

The grizzly bear is a type of brown bear.

©Pat de la Harpe/

Scientific Name

The grizzly bear is a subspecies of the brown bear known as Ursus arctos. Ursus arctos horribilis is the scientific name for these bears. Ursus is Latin for bear, and Arctos comes from Arktos, which is Greek for the word bear. Horriblilis is a Latin term that means horrible.

Appearance & Behavior

Grizzly bears are animals that may be very light brown or dark brown. Grizzlies have large heads, dish-shaped faces, short round ears, and short tails. The stout bears have a large muscular hump on the upper back that provides strength for digging. The claws on the grizzly’s front paws are curved, large, and sturdy, which help the bear dig in the ground for food. The grizzly’s claws are also handy for turning over rocks to find insects. It is not unusual for a male grizzly to be eight feet tall, which is taller than any basketball player. The male can weigh up to 900 pounds. Females are smaller, weighing 300-400 pounds. Grizzlies that live where food is plentiful tend to weigh more. The bears spend most of their time alone, roaming their habitat and searching for food.

Although the grizzly is a loner, it is not unusual to see several grizzlies feeding on the fish near rivers where salmon are plentiful. Grizzly bears are animals that hibernate or are inactive during the cold months. They store enough fat during the summer to sustain them during hibernation. Grizzlies dig a den or find a cave for hibernation. Once a grizzly enters hibernation, it rests there for about five months. During that time, the bear does not eat, drink, urinate, or defecate. In early spring, grizzlies come out of hibernation.

Read about the “Boss” grizzly bear that was hit by a train and survived.

Grizzlies may be very light brown or dark brown and have large heads, dish-shaped faces, short round ears, and short tails.

Evolution and History

While there may be some confusion, the grizzly bear is a subspecies of the brown bear, which migrated from Asia to North America 40,000 – 60,000 years ago. Then, the brown bear seems to have fractured into basically two groups: the coastal brown bear and the grizzly bear.

In the 1800s and early 1900s, biologists determined that there were many species of the grizzly bear – up to almost 90! As time went on, this diminished to less than ten, and now it is only one, which has been confirmed through genetic testing.

There are many similarities and appearances between the Kodiak bear (Ursus Arctos Middendorffi) and the grizzly bear (Ursus Arctos Horribilis), but they are both subspecies of the brown bear. In North America, if you see a brown bear, it could be just a brown bear, or it could be a Kodiak or a grizzly!


Grizzlies require large areas of habitat for roaming and hunting. Females need up to 300 square miles, and males require up to 500 square miles, but grizzly habitats can overlap. The western United States was once a place where grizzlies roamed freely, as far south as Mexico. However, when settlers moved westward, rural development resulted in habitat loss. The invasion of humans sent grizzlies to higher grounds such as the Northern Rocky Mountains and other remote areas of the Northwest. The California Grizzly Bear or Ursos arctos californicus has been extinct since the early 1900s. The grizzly bear is California’s state animal, and the state proudly displays it on the state flag.

Of the remaining 1,500 grizzlies in the lower 48 states, most live in northwestern Montana and in or around Yellowstone National Park. Northern Canada and inland Alaska both have large numbers of grizzly bears. Although grizzlies are considered big game animals, in the continental United States, there are laws to protect the bears from becoming extinct. In 1975, the U.S. Fish and Wildlife Service placed the bears in the lower 48 states on the list of threatened species under the Endangered Species Act.

Humans continue to threaten the grizzly’s habitat. Bears that live near campgrounds can become accustomed to searching for food left behind at campgrounds and garbage disposal areas. Humans who feel threatened by the bears sometimes kill them. Illegal hunting or poaching is still a threat to grizzly bears despite their being on the endangered species list.

A brown Canadian grizzly bear in the Rocky Mountains of Alberta, Canada, standing in the green grass in a clearing, with dense woods in the background

Male grizzlies need about 500 square miles to roam and hunt.

© James Ferguson


Grizzlies are omnivores, meaning they eat plants and animals. Grizzlies eat plant foods such as berries, grasses, roots, mushrooms, insects, and animals like deer, elk, and mice. This bear is known for its love of fish and often lives near remote rivers. The bears are big eaters and can consume as much 90 pounds of food each day, which is like eating more than 350 large hamburgers! When food is scarce, the grizzly may rummage through trash or try to find food at a campground.

The grizzly’s hunting and eating habits play a role in keeping the ecosystem healthy in the areas where they live. When grizzlies consume plant-eating animals, it helps prevents those animals from ruining the plant life in areas where grizzlies roam. As they dig for food, grizzlies turn or till the soil. After feeding, grizzlies leave behind uneaten animal parts and carcasses that decay and serve as a natural soil fertilizer.

What Do Grizzly Bears Eat
Grizzlies eat berries, roots, salmon, and nuts.

Predators & Threats

Movies and television shows portray grizzlies as aggressive toward humans. However, humans are the greatest threat to the bears. These bears keep to themselves and avoid humans. They will flee from dangerous situations but will become aggressive when threatened. If animals or humans try to harm grizzlies or their cubs, the bears can become violent quickly and will attack. About half of grizzly cubs do not live to reach adulthood because of diseases and grizzly predators that include mountain lions, wolves, and adult male grizzlies.

Hiking, Bear, People, Men, Grizzly Bear

Humans are the greatest threat to grizzlies.


Reproduction, Babies, and Lifespan

Grizzlies breed when they are mature, between three and eight years old. The bears mate from May through July with June and July being the peak months for breeding. During the mating period, a male spends about a month with a female and then leaves. The female goes into a den and hibernates during the winter. After about five months, between January and March, the female typically gives birth to two babies, known as cubs, but can produce up to four. Young grizzly cubs feed on their mother’s milk, which is high in fat. The cubs remain under their mother’s protection until they are about two years old. Half of all grizzly cubs are at risk of dying before reaching adulthood because of diseases and predators. Grizzly bears usually live to be 20-25 years old, but some can live up to 30 years.

Grizzly bear with cubs

Grizzlies typically give birth to two cubs but can produce up to four.

© Cooper


There are an estimated 1,500 grizzlies in the lower 48 states, down from 50,000 in the early 1800s. Alaska has about 30,000 Grizzlies, and Canada is home to 26,000. A light-colored grizzly called the prizzly-bear also lives in Alaska. This grizzly-polar bear hybrid is a cross between a polar bear and a grizzly bear.

What do grizzly bears eat - grizzly bear cubs

There are an estimated 1,500 grizzlies in the lower 48 states.

©Volodymyr Burdiak/

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About the Author

Heather Ross is a secondary English teacher and mother of 2 humans, 2 tuxedo cats, and a golden doodle. In between taking the kids to soccer practice and grading papers, she enjoys reading and writing about all the animals!

Grizzly Bear FAQs (Frequently Asked Questions) 

Is a Grizzly Bear an herbivore, Omnivore, or Carnivore?

The grizzly bear is an omnivore, meaning that it consumes plants and animals. Grizzly bears enjoy dining on berries, plants, small and large animals. Grizzlies love eating fish, and especially salmon found the rivers in the Northwestern United States, Alaska, and Canada.

What animal can kill a grizzly bear?

Humans and other bears can kill grizzly bears. People kill grizzly bears by poaching or hunting them illegally. Hunters also mistake them for black bears, which are legal to hunt and kill in the United States. When grizzly bears surprise humans by rummaging through garbage cans or going after food at campsites, the bears are at risk of being killed. Wolves and mountain lions can kill young grizzly bears.

Are grizzly bears dangerous?

Grizzly bears are known for avoiding humans. However, they can be dangerous when threatened. When there is a threat to a grizzly bear or its cubs, the animal will become violent and fight for protection. The grizzly bear’s muscular build, heavy body, sharp claws, and ability to run makes it an animal to be feared and respected.

How fast can a grizzly bear run?

Despite its large size, a grizzly bear can run an astonishing 35-40 miles per hour, significantly quicker than the fastest recorded human at full sprint.

What Kingdom do Grizzly Bears belong to?

Grizzly Bears belong to the Kingdom Animalia.

What phylum do Grizzly Bears belong to?

Grizzly Bears belong to the phylum Chordata.

What class do Grizzly Bears belong to?

Grizzly Bears belong to the class Mammalia.

What family do Grizzly Bears belong to?

Grizzly Bears belong to the family Ursidae.

What order do Grizzly Bears belong to?

Grizzly Bears belong to the order Carnivora.

What genus do Grizzly Bears belong to?

Grizzly Bears belong to the genus Ursus.

What type of covering do Grizzly Bears have?

Grizzly Bears are covered in Fur.

In what type of habitat do Grizzly Bears live?

Grizzly Bears live in forests and mountainous regions.

What is the main prey for Grizzly Bears?

Grizzly Bears prey on salmon, fruit, and fish.

What are some distinguishing features of Grizzly Bears?

Grizzly Bears have strong, powerful shoulders and enormous claws.

What are some predators of Grizzly Bears?

Predators of Grizzly Bears include humans and cougars.

What is the average litter size for a Grizzly Bear?

The average litter size for a Grizzly Bear is 2.

What is an interesting fact about Grizzly Bears?

Less than 10% of Grizzly Bears make it into adulthood.

What is the scientific name for the Grizzly Bear?

The scientific name for the Grizzly Bear is Ursus Arctos Horriblis.

What is the lifespan of a Grizzly Bear?

Grizzly Bears can live for 15 to 25 years.

What are the differences between grizzly bears and Kodiak bears?

Grizzly bears are smaller than Kodiak bears. They are also located in different areas, as Kodiak bears are only found in the Kodiak Archipelago in Alaska.

Who would win a fight between a king cobra and a grizzly bear?

A grizzly bear would win in a fight against a king cobra.

To be clear, a king cobra will certainly kill a grizzly bear, but the chances are good that the grizzly bear will kill the snake before expiring. If the two animals met on a neutral ground that disallowed any ambush, the grizzly bear could kill the snake outright.


Will grizzly bears be introduced into their former range?

Grizzly bears used to live across a much larger range. Specifically, they roamed across California and Arizona, both places today they’re no longer found. In 2019, Arizona’s Center for Biological Diversity filed a lawsuit against the U.S. Fish and Wildlife Service for not having a recovery plan that would restore grizzly bears to their historical range. If challenges are successful, this could lead to grizzly bears around the Grandy Canyon and other locations in their historical range.

Who would win a fight between a grizzly bear and an alligator?

A grizzly bear would win a fight against an alligator.

Although the alligator has a very powerful bite, it cannot match the grizzly bear for sheer power. The best-case scenario for the alligator is that it ambushes the grizzly bear on land. Even in that case, the alligator might bite a leg, but it would catch a swift, smashing paw to the head that has enough power to knock it unconscious.

Who would win a fight between a Grizzly Bear and a Siberian Tiger?

A Siberian tiger would win a fight against a grizzly bear. The Siberian tiger is an ambush predator, and it’s the only big cat that comes close to the grizzly bear in terms of size and power. Size isn’t everything, though.

Siberian tigers are born killers that hunt with precision and devastating power. This combination leads us to believe that a Siberian tiger would get the drop on the grizzly bear, and it would deliver a deadly attack that the bear cannot counter.

Thank you for reading! Have some feedback for us? Contact the AZ Animals editorial team.


  1. David Burnie, Dorling Kindersley (2011) Animal, The Definitive Visual Guide To The World's Wildlife / Accessed November 10, 2008
  2. Tom Jackson, Lorenz Books (2007) The World Encyclopedia Of Animals / Accessed November 10, 2008
  3. David Burnie, Kingfisher (2011) The Kingfisher Animal Encyclopedia / Accessed November 10, 2008
  4. Richard Mackay, University of California Press (2009) The Atlas Of Endangered Species / Accessed November 10, 2008
  5. David Burnie, Dorling Kindersley (2008) Illustrated Encyclopedia Of Animals / Accessed November 10, 2008
  6. Dorling Kindersley (2006) Dorling Kindersley Encyclopedia Of Animals / Accessed November 10, 2008
  7. David W. Macdonald, Oxford University Press (2010) The Encyclopedia Of Mammals / Accessed November 10, 2008