Scientists affiliated with American Museum of Natural History, City College of the City University of New York, have confirmed that grizzly bears have moved northward into Manitoba, Canada -- previously considered to be the exclusive realm of polar bears.
But in a paper published in the current issue of Canadian Field-Naturalist, they write that grizzlies -- Ursus arctos horribilis -- have been seen in Canada's Wapusk National Park with increasing frequency.
An Environment News Service story says that the park protects one of the world's largest known polar bear maternity denning areas. The grizzlies were seen along fish-filled rivers or in areas with berry crops.
"Grizzly bears are a new guy on the scene, competition and a potential predator for the polar bears that live in this area," Robert Rockwell, a research associate at the Museum and a professor of biology at CUNY, told ENS.
The researchers first spotted a grizzly in 2008. They were flying over the area and graduate student Linda Gormezano, a co-author of the current paper, shouted that she saw one. Rockwell and Gormezano then looked through records for reports of other sightings. There were none before 1996. But between then and 2008, there were nine confirmed sightings, and three more in the summer of 2009.
The researchers worry that grizzlies that stayed in the area would kill polar bear cubs when they come out of hibernation.
"A big question is how to deal with these new residents," Gormezano told ENS. "In Canada, both the polar and grizzly bear are federally listed as species of special concern. In Manitoba, the polar bear is provincially listed as threatened while the prairie population of the grizzly bear is listed as extirpated."