Hybrid Polar/Grizzly Bears showing up in the Arctic
Two Canadian biologists have reported sighting a handful of grizzly bears and hybrid grizzly/polar bears at unusually high latitudes in the Arctic, indicating that the interbreeding of the two bear species is becoming more common as the climate warms and grizzlies venture farther north. The sightings of three grizzly bears and two hybrid bears, made in late April and May, represent an unprecedented cluster of these animals at such high latitudes. The biologists even took DNA samples from a grizzly bear at 74 degrees North latitude.
The report of the sightings comes on the heels of a recently published analysis of newly sequenced polar bear genomes, suggesting that climate change and genetic exchange with brown bears helped create the polar bear as we know it today. The genetic mixing that the Pennsylvania State and University of Buffalo analysis identified happening in the past — in which polar bears would interbreed with grizzly bears as the polar bears' sea ice habitat shrunk — is now happening again, according to bear biologists.
The sightings this spring represent the fourth and fifth confirmed hybrid bear sightings in recent years. Scientists say that it is evident from reports from Inuit hunters that many other animals are adapting their lifestyles to changes in climate, just as grizzlies did when they split from polar bears four to five million years ago.
When University of Alberta biologists Jodie Pongracz and Evan Richardson flew up to Viscount Melville Sound in the High Arctic of Canada this spring to capture and satellite-collar polar bears, they were astonished to see a grizzly bear travellng with what they initially thought was a polar bear hundreds of miles north of where brown bears are normally found. That sighting occurred on April 23 in Wynniatt Bay at 73 degrees North latitude. Upon closer examination, the polar bear turned out to be a hybrid cross between a polar bear and grizzly.
Photo of hybrid Polar - Grizzly bear via goallover.com
Read more at Yale Environment 360.