Polargrizz? Grolarbear? Pizzly? Polzy? We're in Trouble!

Within the past year a good friend of mine brought to me a fairly old piece of news. But figuring I'm not the only one left in the dark about the this intriguing subject, I thought I would share a little about the Polar Bear/Grizzly Hybrid.

Polar and Grizzly Hybrid

This Ursid Hybrid been historically documented and confirmed with DNA testing since a hunter (with a Polar Bear license) shot one in 2006 on Banks Island in Canada's Northwest Territories. It had thick, creamy white fur, typical of polar bears, as well as long claws; a humped back; a shallow face; and brown patches around its eyes, nose, and back, and patches on one foot, which are traits of grizzly bears. A DNA test conducted by the Wildlife Genetics International in British Columbia confirmed it was a hybrid, with the mother a polar bear and the father a grizzly. It is the first documented case in the wild, but it was known that this hybrid was biologically possible because other other polar/grizzlies have been bred in zoos in the past. According to Paetkau, the genetics expert, grizzly and polar bears are the most closely related of the living bear species.

Scientists argue that hybrids do not support climate change because these hybrids have happened in the past; A few instances aren't enough. But these "rare" instances are occurring more and more frequently now--and it's not like polar bears and grizzly bears have always been friendly together. The interactions are usually aggressive. It is not uncommon for bears to encounter each other in the wild and to view each other as prey, even within the same species.

Additionally, while the two species are genetically similar and often found in the same territories, they tend to avoid each other in the wild. They also fill different ecological niches. Grizzlies tend to live and breed on land. Polar bears prefer the water and ice, usually breeding on the ice.

Multiple bear species have been crossbred in zoos. Scientists just never expected a polar bear and grizzly to mate in the wild. Zoo animals are caged together- wild bears roam free. It is an unusual for mating to occur in the wild because both species require an extended mating ritual to reproduce. Females ovulate only after spending several days with a male and then mate several times over several days to ensure fertilization. How long can two conflicting species tolerate each other, even during the season of love?


Chance encounters could happen periodically. But since the offspring are weird looking and probably outcasts, they may have low reproductive success and thereby fail to pass their genes on to the next generation. Polar bears would most likely prefer to mate with other polar bears, and grizzlies with other grizzlies, rather than with an odd-looking hybrid. And looking at "pure DNA" neither species have had much interbreeding. But fairly recently, in 2010, an Inuvialuit hunter from Ulukhaktok on Victoria Island shot what he thought was a polar bear. After inspecting the bear and having DNA testing done, it was found that the bear's mother was a grizzly-polar hybrid and the father was a grizzly bear. It may be the first recorded second-generation polar-grizzly bear hybrid found in the wild.


So why is this happening? Well, climate change may also play a role, causing an increasing overlap in range and mating season and territory.  The warming Arctic environment is causing some animals to shift their range northward. Hunting policy itself may play a role, reducing the number of males and driving the females to mate with the next best available male-- a male grizzly bear.

This hybridization and  climate change is all a natural part of life. The world is always changing--sometimes faster, sometimes slower. Dinosaurs go extinct, mammals take over. The climate warms up, insects take over. Polar bears go extinct, grolar bears take its place.

Say bye-bye to these babies.

The grolar and prizzly bears may not make a significant difference in the environment, but they aren't something to take lightly. Their physical traits are generally an intermediate between the polar bear and the grizzly bear. Their bodies are smaller than polar bears, but larger than grizzlies, while their heads fall between the broader grizzly head and the leaner polar bear head. They have the long claws of polar bears, and the hollow fur of They have long necks like polar bears, but small shoulder humps like grizzlies. The soles of the hybrids' feet are partially covered in hair; polar bears have hair-covered soles, which act as insulation, and grizzlies have hairless soles.

As for behavior and temperament, the hybrids demonstrated behavior more similar to polar bears than grizzlies.  They stamped toys similar to how polar bears break ice, and hurled bags to the side as polar bears may hurl prey. Grizzlies given the same bags do not demonstrate this hurling behavior. The hybrids were also observed lying down similar to polar bears: on their stomachs with rear legs splayed.


What this could mean is we get a bear bigger than a grizzly bear, that can tolerate both a warmer climate and a cooler one. While the grolar bear has the behavior and temperament like of a polar bear, the hybrids are more likely to breed with grizzlies, bears known for being the most aggressive of all. Grizzly bears are omnivores, and polar bears ares are omnivore, but grolar bears are likely to be omnivores because of their available food on land. But what we could get is one fierce bear to contend with.

They could be as scary as these guys.