Polar bears are becoming the poster-species for "doomsday prophets" of climate change, even though groups pushing for higher protection for the animals don't have the evidence to prove their case, Nunavut's manager of wildlife says.

"It makes a great story because it is simple and intuitive," Dr. Mitch Taylor wrote in a 12-page document for the U.S. Fish and Wildlife Service's review of the animal's status. "However, the reality is much more complex."

The USFWS review follows a petition from the Centre for Biological Diversity, Greenpeace and other groups, who want polar bears upgraded to "threatened" on the U.S. Endangered Species list.

The groups say the animals' population is suffering because of climate change, development and contaminants.

While Taylor said it's expected that climate change will affect all species worldwide, that shouldn't mean governments should rush to list every one as "threatened".

Delving into the patterns of polar bear eating habits, ice floe loss, population densities and other issues, Taylor downplays the overall impact of climate change.

"No evidence was presented by the proponents and no evidence exists that suggests that both bears and the conservation systems that regulate them will not adapt and respond to the new conditions," he said. "Polar bears have persisted through many similar climate cycles."

He said no one is suggesting that climate change isn't affecting some polar bear populations, but noted there are 20 polar bear populations in the world and each one should be considered independently.

"The references listed [in his document] suggest that each polar bear population is unique with respect to seasonal cycles, sea ice conditions, prey base, summer-retreat areas, and fidelity," he wrote.

"The 20 existing populations of polar bears are not all identical to the two populations that constitute the majority of the examples in the petition.

Taylor says many of the groups filing the petition have a long history of opposing hunting.

He said Canada has one of the best management systems for polar bears in the world, allowing Inuit to hunt in a sustainable manner and generating $3.5 million in Canada through sport hunts and the sale of hides.

"At present, the polar bear is one of the best-managed of the large Arctic mammals," Taylor said. "If all the Arctic nations continue to abide by the terms and intent of the Polar Bear Agreement, the future of polar bears is secure."

Taylor noted the estimated number of bears on the Boothia Peninsula, 1,300 kilometres west of Iqaluit, has actually increased to 1,500 animals from 900. He said environmental groups don't seem to want to take information like that into consideration when pressing their case.

"Life may be good, but good news about polar bear populations does not seem to be welcomed by the Centre for Biological Diversity," he said.