Andrew Derocher, professor of biology at the University of Alberta in Edmonton, Canada, shared his personal stories and extensive knowledge about polar bears with Iowa State students and others in attendance during a lecture Thursday.
“If there’s no ice, there’s no ice bear,” Derocher said to the hundreds seated in the Great Hall of the Memorial Union. The theme of his lecture was the effects of climate change and pollution on polar bears.
Derocher's field work involves observing polar bears in the Canadian Arctic, Hudson Bay and Svalbard, Norway, where he worked with the Norwegian Polar Institute.
More recently, Derocher has focused his research on the effects of climate change and toxic chemicals on polar bears.
In his lecture, Derocher cited many consequences of “climate warming” in relation to polar bears, the obvious one being less ice, which is the polar bears' natural habitat. Since ice is also home to their prey, the ringed and bearded seals, he said that when it melts polar bears are forced to fast more and feed less. “We’re affecting their access to their food,” he said.
A lack of food also increases polar bear activity, as they need to travel more in search for their next meal. This results in bears with low body conditions who are unfit to reproduce or rear their cubs, causing overall population decline.
Because polar bears have small litters of only one to two cubs and a long lifespan of 24 to 28 years, Derocher said it takes longer for polar bears to recover following a decline in population.
The major factors affecting the polar bears’ habitat include arctic shipping, oil and gas development and endocrine disrupting pollutants, Derocher said.
He also said that human interaction has become more of an issue. Since their natural habitats are shrinking, the bears are moving closer to towns in the northern parts of Canada and Europe. They are hunted regularly as trophy animals. Derocher said their furs often fetch about $7,000.
Despite these threats, Derocher said polar bears still number up to 25,000 in the wild and that “polar bears should persist to the end of the century.”
Derocher said he doesn’t want to “save the bears” and that he is strictly an advocate for the science of polar bears. He also stressed that he is not a climate scientist, but that “the only conservation solution is reducing greenhouse gas production.”
A large amount of data exists on polar bears thanks to cooperation between scientists around the world, Derocher said. He also acknowledged how easy it is to study them due to their “curious” nature.
“We know what’s going on with these animals,” he said. “We can really monitor these bears right when they leave the den.”
Derocher showed the audience a video of him and his colleagues following a polar bear via chopper, eventually firing a tranquilizer dart at it. Attendees were also able to view pictures of Derocher with polar bear cubs and half-eaten seals.
Derocher’s lecture was a part of an annual lecture program that honors Paul L. Errington, who was a professor of wildlife biology at Iowa State. There was a significant number of students in attendance.
“I think it’s interesting that polar bears consume mostly fat from prey and can survive off it for so long due to certain hormones and that pollutants can disrupt the functionality of these hormones,” said Erika DeSmidt, sophomore in animal ecology. DeSmidt also attended a seminar led by Derocher earlier Thursday.
Haley Carr, junior in animal ecology, appreciated that Derocher didn’t identify as a polar bear advocate, but rather as a polar bear scientist who offered “scientific options for solving the issues.”
Derocher’s research on polar bears spans two decades and has focused on the limiting and regulating factors of polar bear populations including habitat use, harvest effects and predator-prey relationships, according to Polar Bears International, where Derocher serves as a scientific adviser.
Derocher will participate in another seminar sponsored by the NREM GSO Seminar Committee in room E164 of Lagomarcino Hall at 3:10 p.m. Friday.