Anthony Armentano, Global Animal

According to the International Union for Conservation of Nature (IUCN), the polar bear population has decreased by over 30 percent in over 45 years. Not only do these bears suffer from a dwindling environment, but they face other pressures as well. The good news is that polar bears seem to be finding a way to adapt to their conditions. However, whether or not that adaptation leads to the disappearance of what we know as the polar bear today, remains in question.

Polar bears continue to feel the effect of multiple pressures on their environment. Photo Credit: WWF
Polar bears continue to feel the effect of multiple pressures on their environment. Photo Credit: WWF

It’s no secret that global warming has been increasingly rough on this species of bear in particular, affecting both their environment and availability of their food sources. As the ice melts, polar bears lose their homes as well as their hunting grounds. The receding ice forces the bears to retreat back to land, alienating them from their food sources. During their migration period, polar bears survive off of fat reserves they build up during their active hunting season.

As a result of global warming, Dr. Seth Cherry, of the University of Alberta, claims, “In recent years, polar bears are arriving on shore earlier in the summer and leaving later in the autumn.” This change in migration extends the period of time polar bears aren’t out hunting, and therefore not collecting enough fat to help them survive through their off-seasons. 

Additionally, polar bears are threatened on a second front. Despite their “vulnerable” status on the IUCN’s Red List, these animals are prominent hunting targets. Since 2011, the Nunavut territory of Canada has increased the hunting quota for a single polar bear population from eight to 24, which researches believe could be potentially detrimental to the polar bear community.

Polar bear hunting seems to persist primarily due to superficial reasons. Hunters all over the world have a chance to boost their precious egos, by receiving either the “North American 29” or “Bears of the World” award—both of which list the killing of polar bears as a qualification.

Give these multiple dangers for the polar bear community, the bright side is that some bears seem to be finding a way out of their harsh conditions. Both polar bears and grizzly bears hold a similar ancestor—the brown bear. Millions of years ago, these two bear species split from their ancestor, and polar bears began to adapt to their cold, oceanic environment. Now, as a result of their extended migrations away from the ocean, some polar bears have begun to mingle with grizzly bears once again.

In 2006, the first hybrid offspring of a polar bear and grizzly bear was confirmed by means of DNA testing. Furthermore, in the spring of 2012 another small handful of these hybrid bears appeared once again. Information from the Pennsylvania State and the University of Buffalo claim that in the past, interbreeding would occur between the two species whenever the polar bears’ environment would shrink—a pattern that seems to be occurring once more.

Conversely, Andrew Derocher, a scientist at the University of Alberta, remains skeptical on the hybridization of polar and grizzly bears. Derocher explains, “It will take a long time for the few genes that move between the species to have any effect.” He feels that not enough of the polar bear community interacts with grizzlies to support any prominent change in species.

However, evolution is absolutely unpredictable. Even Derocher describes the phenomenon as, “a fools game and how this plays out is anyone’s guess.” Nevertheless, the hybridization of polar bears with grizzlies indicates an adaptive change in the polar bear species. It’s a warning to the world that their environment is disappearing before our eyes, and only time will tell what the future holds for polar bears.