Polar Bears vs. Grizzly Bears: Which Would Win in a Fight?

Written by Michelle Stacy
Published: September 20, 2021

We’ve all heard of polar bears and grizzly bears, but if you had to guess which one was the more dangerous species, what answer would you give? The truth is, with climates rapidly changing there have been showdowns that pit polar bears vs. grizzly bears and one of the species has come out on top. Let’s dive into the differences between polar bears and grizzly bears and then see which one of these animals is the top dog in a fight.

Polar Bear vs. Grizzly Bear

Polar bear vs Grizzly - Showdown
Its a showdown between bears!

Polar bears and grizzly bears are both mammals in the Ursidae family. They’re both extremely large bears, although polars bears take the crown of being the largest bear species. In fact, polar bears stand out in a number of ways:

  • Polar bears are generally more aggressive than grizzly bears. Example: in the northerly Norwegian islands of Svalbard, there is a significant polar bear population. They’re aggressive enough that when outside settlements it’s mandatory to carry firearms to scare off polar bears.
  • Polar bears have higher metabolisms: Here’s a shocking fact, grizzly bears don’t eat much meat. Just 10% of their diet is is meat as they prefer berries and flowering plants. Compare this to polar bears who almost exclusively eat meat.
  • Polar bears don’t hibernate: Grizzly bears will fatten up for long winter hibernations. Polar bears welcome the harshest winter conditions and continue hunting year round.

Add it up and you have polar bears being more aggressive, eating almost a diet almost exclusively composed of meat while grizzly bears forage berries, and hunting through the worst of the winter while grizzly bears nap away.

Sounds like it’d be no contest that a polar bear would win in a fight, right?

Who Would Win in a Fight Between Grizzly and Polar Bears?

Polar Bear vs Grizzly - Polar Bear
Polar bears are fierce, but will they fight?

The answer of who reigns supreme in a fight pitting polar bears vs. grizzly bears may surprise you.

A study from 2015 looked at interactions between grizzly and polar bears. Historically, grizzly and polar bear territories haven’t overlapped. However, with changing climates extending grizzly ranges north, the two species are increasingly encountering one another. Especially along Alaska’s north coast, events like beached whales create environments where the two bears will compete for very large meals.

Here’s a sample directly from the study.

Our results indicate that grizzly bears are socially dominant during interspecific competition with polar bears for marine mammal carcasses during autumn.

Journal of Mammalogy, 24 November 2015

Put more bluntly, when polar bears and grizzly bears are both competing for food, its the polar bears that are more likely to walk away from conflict and leave the prize for grizzly bears.

The bottom line: in a fight between a polar bear and grizzly bear, the grizzly bear reigns supreme.

Advantages in a Fight Between Grizzly Bears and Polar Bears

Polar Bear vs Grizzly - Two Grizzlies Battle
Two grizzlies battle

We’ve seen the study that says polar bears are more likely to concede prey to grizzly bears, but if the two were to battle, what advantages does each species have?

After all, polar bears may simply be more willing to concede prey to save precious calories from fighting. In the event an actual fight took place, results may be different.

So, which species has the upper hand?

Polar bears are generally larger. Male polar bears have an average of 770 to 1,500 pounds. The largest subspecies of brown bear, the Kodiak bear, has an average weight of 660 to 1,320 pounds. Male grizzly bears whose range overlaps with polar bears average closer to 400 to 790 pounds. The largest polar bear ever recorded weighed 2,209 pounds, while few grizzly bears on record weigh more than 1,700 pounds.

Polar bears have enormous paws that helps them walk along ice. This makes their claws shorter and sharper. If the two were hitting each other with their claws, it’s likely the brown bear would have the advantage as their claws are more adapted to swiping.

If a battle between grizzlies and polar bears turned into a wrestling match, the advantage could swing to polar bears. When polar bear males battle (playfully or not), they tend to wrestle and bite at each other’s necks.

Encounters between grizzlies and polar bears have been reported in past literature; in these encounters grizzly bears killed denning female polar bears while at a significant size disadvantage.

Make Love Not War: The Emergence of Pizzly Bears

Polar Bear vs Grizzly - Pizzly Bear
Pizzly bears have long claws and whiter coats

However, all the talk about whether a grizzly bear or polar bear would win in a fight might be missing the mark. In 2006 an an odd-looking polar bear was shot in Canada. The bear was white, but had longer claws and other features that were similar to grizzly bears. DNA analysis quickly confirmed that the bear’s father was a brown bear and its mother a polar bear.

The result: a pizzly bear. A hybrid animal that’s part grizzly and part polar bear.

The two species can mate because they’re genetically very similar. In recent years, more than a half dozen pizzly bears have been discovered across Alaska and Canada. Their continued discovery shows that the range of the two species are increasingly overlapping, and they’re choosing to make love rather than war.

Comparing Polar Bears vs. Grizzly Bears

Polar BearGrizzly Bear
Heaviest Recorded2,209 pounds1,700+ pounds
Average Length of Mature Male8-8.4 feet>7-10 feet
Main method of fightingWrestling and biting at the neckSwiping with front claws
Average weight900-1,500 pounds400-790 pounds
Lifespan25-30 years20-25 years

Polar Bear vs. Grizzly Bears: The Main Differences Explained

Let’s examine the key differences between grizzly and polar bears.

What is a polar bear?

Polar Bear Cub
A polar bear cub with its mom

A polar bear is a species of large-bodied bear that ranges from Greenland and Svalbard (Norway’s arctic archipelago) in the north to Alaska in the south, although they are most common in and around sea ice in the Arctic Ocean and in the Northwest Passage, to the east of Russia, Canada, and Greenland. Although all polar bears have white fur, they vary in color due to varying melanin concentrations in their fur. It is also said that polar bear fur has no color; instead it reflects the colors of its surroundings. 

Polar bears live on land, too, but not all polar bears live in Arctic regions. A rare type of polar bear lives along the coast of Russia near the Sea of Okhotsk, the Bering Strait, and the Chukchi Sea, which is also sometimes called the “polar bear’s backyard.” Polar bears live in Arctic regions, but they do come down to the lower latitudes in the winter to forage on the sea ice and fish. Polar bears are the largest bear species on average and are born with thick layers of fat, which they need to keep warm.

What is a grizzly bear?

Strongest animal bite – Grizzly bear
Grizzly bears feast on everything from salmon and trout to large animals such as moose and elk.

Grizzly bears are found throughout much of North America and Alaska, where the winters are cold. The species will build up their body fat in preparation for the winter season. In winter they will hibernate for up to seven months, not even waking to go to the bathroom. The bear will prepare by digging a hole for their den, usually in a hillside. Once inside, they slow down their body functions such as heart rate, temperature, and metabolism. This allows the fat reserves to last longer. If a female grizzly is pregnant she will give birth in the den, nurse her cubs until spring and the cubs are old enough to explore outside the den. 

Polar bears diet vs. Grizzly Bear Diet

Polar bears eat primarily seals. Although these seals are numerous throughout the Arctic Circle, many polar bears avoid moving too far north to capture them. The reason for this is because the ocean around the polar bear’s natural habitat is ice-covered during the winter. Without a healthy seal population to hunt, these polar bears are forced to eat other prey such as walrus or even beluga whales. Because polar bears are very dependent on seals for their diet, seals have evolved to be wary of approaching polar bear dens during the spring and summer months. 

Grizzly bears are opportunistic feeders, they eat almost anything they can get their paws on, including carrion, insects, eggs, fish, rodents, ground squirrels, carrion, moose, elk, caribou, and deer. They will also eat many types of plants including those with fleshy roots, fruits, berries, and grasses. In some areas of Alaska, they’ve even been known to attack cars when drivers do not slow down quickly enough.

Habitat of grizzly bears vs. polar bears

Grizzly bears generally live further south than the Arctic regions of polar bears. Today they live across much of Western Canada and Alaska. Polar bears, on the other hand live on the northern edges of North America and have a range that extends all the way to the North Pole. Since polar bears’ main diet is seals, they remain close to water and rarely travel inland.

On average, polar bears inhabit and are found in the ocean’s Arctic waters, while grizzlies stay in terrestrial regions.

Are Polar and Grizzly Bears Endangered Species?

Biggest Animals Ever to Walk the Earth: Polar Bear
Polar bears are threatened by climate change

Both polar and grizzly bears are both protected species. The International Union for the Conservation of Nature classifies polar bears as “vulnerable”. Their habitat has been decreasing due to human activity. Climate change and disappearing sea ice are putting polar bears at risk. These animals need frozen sea ice to hunt seals for food. Polar bears face the threat of extinction due to global warming. Grizzly bears were almost extinct from the western United States and into Mexico due to control actions and habitat loss. In 1975, conservation efforts have helped the grizzly bear population recover in some of these areas.