Select Page

The pizzly bear is a hybrid animal discovered in the wild in 2006, but what exactly is the difference between a pizzly bear, a grolar bear, and the bears we normally see in the wild?  

A pizzly bear is the hybrid offspring of a male polar bear and a female brown bear. Grolar bears have a brown bear father and a polar bear mother. The first pizzly bear was born in 1936 in The Smithsonian National Zoo, but the first wild hybrid was not found until 2006.  

This article looks into what a pizzly bear is and its history and characteristics. With their numbers on the rise, you may see one in the wild.

10 facts about pizzly bears infographic

What Is A Pizzly Bear?

The pizzly bear is the hybrid offspring of its parents, the polar bear, and the grizzly bear. They are also known as grolar bears, another combination of their parents’ names.

If the father is a polar bear and the mother a brown bear, the offspring would be called the pizzly bear.

If the father was a grizzly and the mother a polar bear, biologists have suggested they are called the grolar bear. With so few grizzly-polar bear hybrids found, no firm naming convention exists.

Wildlife officials from Canada also have another name for this hybrid bear. Officials have combined the Inuit names for both of the parent species. The Inuit name for the polar bear is Nanuk, while the Inuit name for the grizzly bear is Aklak.   

The combination of both names has led to the pizzly bear being called the Nanulak. Although there is no scientific name for this hybrid of bears, this may be the most appropriate name for their parentage.

Pizzly bears typically exhibit physical characteristics and traits of both parent species. They may have the body shape and fur coloration of a polar bear, with the hump on the back characteristic of a grizzly bear. The extent of their physical features can vary widely among individual hybrids.

These hybrid bears have been observed in regions where polar bears and grizzly bears’ habitats overlap, such as in parts of Canada and Alaska. Climate change and the melting of Arctic ice have led to greater opportunities for these two bear species to come into contact, increasing the chances of interbreeding.

Pizzly bears represent an interesting aspect of the impact of climate change on wildlife and the potential for the hybridization of species due to shifts in their ranges and habitats.

Want to find out if bears can climb trees? Find out here.

When Was The First Pizzly Bear Discovered?

The history of the pizzly bear dates back to 1936, due to an accident at the Smithsonian National Zoo in Washington, DC. A male polar bear and a female brown bear mated at the zoo.

The male polar bear entered the female brown bear’s enclosure, resulting in the female having three cubs. These three cubs grew to adulthood, later breeding themselves.

This incident proved that polar bears and grizzly bears could mate, and their offspring could also mate, unlike most hybrid animals. Many hybrid animals are born sterile and are unable to create offspring.

Two cubs were also born at Osnabrück Zoo in Osnabrück in 2004. Unfortunately, one of the cubs was shot when it escaped when the zoo was open in 2017.

Do bears have tails? Find out here in another article I have written

Photo of pizzly bear
Pizzly bear courtesy of Messybeast

When Was The First Pizzly Bear Discovered In The Wild?

In 2006, the first confirmation of a grizzly-polar bear hybrid was found in the wild. DNA testing of the bear near Sachs Harbour, Northwest Territories, on Banks Island showed the bear was a hybrid of two species.

Although the polar bear and grizzly bear had mated in the Smithsonian National Zoo 70 years previously, it was thought unlikely to happen in the wild. Brown bear and polar bear habitats do not overlap in many places, and the two species are generally aggressive toward each other.

This animal was the first pizzly bear found in the wild. The combination was the offspring of a male brown bear and a female polar bear. The hunter had killed the bear thinking it was a polar bear, but officials noticed it had different features to a typical polar bear. It is thought that this female had also given birth to seven other pizzly hybrids over the years.

The bear had thick fur characteristic of polar bears and a humped back, shallow face, long claws, and brown patches around its features and feet, usually seen on brown bears.

What Are The Characteristics Of A Pizzly Bear?

The pizzly bear is the offspring of a polar bear and a grizzly bear, and they share characteristics of both bears while being different from both parents.

The pizzly bear’s body size is larger than a grizzly bear’s but smaller than a polar bear’s. Whereas a polar bear has an extended, sleek profile, the grizzly bear has a much rounder, thicker head. 

Pizzly bears have a head shape somewhere between the lean polar bears and the broad grizzly bear head. The neck leading from the medium-sized head has more in common with that of a polar bear. The pizzly bear has a shoulder muscle hump, although this is much smaller than a grizzly bear.

In pizzly bears that have been studied, most had feet with some hair on the soles. This is characteristic of the polar bear, which has hair on its soles to keep its feet warm.

Pizzly bears have creamy-white fur like the polar bear but with brown patches on the legs, paws, and around the eyes, similar to a brown bear. The skin on the pizzly bear is also a combination of the types found on both parents. Whereas a polar bear’s hair is hollow, the fur of a grizzly is generally solid, with some concave regions, depending on where the hair is taken.

When studying a pizzly bear’s hair, it was noted that the hair on the back was generally hollow, while the hair taken from the paws was almost solid. The feet of the pizzly bear are large, looking more like brown bears, and the claws are long, unlike polar bears. These long claws make the pizzly bear less stable on the ice than a polar bear.

The evolution of bears is fascinating. Find out more here

Pizzly Bear
Pizzly Bear – Courtesy of Corrado

How Many Pizzly Bears Live In The Wild?

Eight pizzly or grolar bears have been killed by hunters or live-captured. These eight bears identified include four first-generation pizzly bears with a 50:50 split between brown and polar bears. One female polar bear was the mother of all four first-generation (F1) hybrids.

The second set of hybrids identified included four backcross individuals with a mix of 75:25 in favor of grizzly bears. It is believed that a single hybrid (F1) female is the mother of all four of these backcross individuals.

After the first pizzly was identified in 2006, the next pizzly bear found was a suspected polar bear killed in 2010. The father of this bear was a grizzly bear, and the mother was a polar bear. All of the offspring relate to a single female polar bear.

Due to the limited areas where grizzly bears and polar bears overlap, the number of pizzly bears in the wild is likely to be low. Robert Rockwell, an ecologist at the American Museum of Natural History in New York City, backs this up. Rockwell says that he doesn’t think there is much pressure for grizzly bears and polar bears to interbreed, stating, “I think the numbers are such that a hybrid would be pretty rare.”

Where Do Pizzly Bears Live?

The first pizzly bear was found in the wild in 2006. This hybrid animal was found on Banks Island in the Northern Territories in Canada. In 2010, a pizzly bear was found on Victoria Island, close to the Northern Territories.

Brown bears and polar bears are known to encounter each other in northern parts of Canada and Alaska. Brown bears have been seen as far north as Banks Island and Victoria Island. Grizzly bears have also been seen in the province of Nunavut for the last 50 years.

Polar bears and brown bears also overlap around the Beaufort Sea in the western Canadian Arctic. Brown bears have been seen in Spring going out onto the ice to feed on seals that polar bears have killed.

While interactions between grizzly bears and polar bears can be aggressive outside the breeding season, the meetings are not as dangerous when mating season occurs.

Hybrid bears are mostly found around the Northern Territories in Canada. Brown bears and polar bears do not overlap in many places in the wild. However, they can be found in the same habitat in Northern Manitoba and on the north edge of Alaska.

Polar bears are apex predators. Please find out how they hunt in this article I wrote.

Polar bear face on left, brown bear face on right
Polar bear (L) Brown bear (R)

How Do Pizzly Bears Mate?

The mating season for the polar bear and the grizzly bear overlap, increasing their chances of breeding. The breeding season of a polar bear is from May to July, while the mating season of a grizzly bear is between April and June.  

Females and males have a long mating ritual that lasts several days. Females ovulate after spending several days with the male and mate several times over a few days.

Both brown bears and polar bears share a similar pregnancy and are both able to delay implantation. Delayed implantation occurs when the embryo develops as far as the blastocyst stage but then enters metabolic dormancy, sometimes for several months. The egg is fertilized and then develops into a tiny blastocyst embryo.

The female bear carries the blastocysts until they are ready before implanting the embryo into the womb. Brown bears delay implantation until they have put on enough weight to make it through the winter.

Bears can often be seen playing with each other, but do you know why? Find out in this article I wrote.

Is The Pizzly Bear Sterile?

Pizzly bears have been known to give birth and are not sterile as most hybrid animals are. Many hybrid animals cannot produce sperm or eggs and are infertile because the parent’s chromosomes do not match up.

The pizzly bear is not sterile as the brown bear and polar bear chromosomes match up. Various second and third-generation pizzly bears have been found. Polar bears are believed to have evolved from brown bears isolated on coastal enclaves as recently as 800-150 thousand years ago.

Are Pizzly Bears Dangerous?

As the offspring of two of the most dangerous bears in North America, the polar bear, and the grizzly bear, there can be no doubt that the pizzly bear could be dangerous. No one has been attacked by a pizzly bear, as far as records show; however, this is possibly due to the species’ low numbers.

Pizzly bears are known to be far less aggressive than either parent species alone and tend to lead solitary lifestyles. In some cases, they may extend their range into populated areas due to limited habitat availability, raising safety concerns for locals unfamiliar with nocturnal wildlife behaviors.

Are Hybrid Animals Good or Bad for the Species?

The pizzly bear is an example of the hybridization of two different species and has caused controversy, primarily from a conservation standpoint. On one side are those who view the pizzly bear as helpful in preserving both species since it can help create a hybrid species to adapt better in changing climates.

However, on the other hand, some argue that these hybrid animals may be harmful to species because they aren’t true representatives of either, creating new problems regarding genetic diversity between species.

Hybridization may blur species distinctions and genetically weaken the gene pool, especially if the hybridized animal cannot reproduce. However, pizzly bears are one of the few hybrids that can produce offspring.

Pizzly bears have adapted to Arctic conditions by mixing polar bear genes with brown bear genes, which makes them better hunters and could help increase the polar bear population in an ever-warming climate.

References and Further Reading

Washington Post – Remembering when things got a little freaky at the National Zoo.

Nautilus – A Strange New Gene Pool of Animals Is Brewing in the Arctic

Frontiers – Demystifying Negative Connotations of Hybridization for Less Biased Conservation Policies

UNL.Edu – Hybrids and Policy

IUCN Red list – Polar bear

LiveScience – Pizzly bear hybrids are spreading across the Arctic thanks to climate change