Scientists use paw prints to track polar bear numbers
A Canadian researcher is using new technology to try to "fingerprint" polar bears in an effort to discover how hunting and climate changeare affecting their population.
The new technique, which has been used on rhinos in Africa and tigers in India, could allow scientists to keep much closer tabs on bear numbers in the face of Inuit hunting pressures and the threat to their icy habitat from global warming.
"We have no idea what's going on with our bears most of the time in the high Arctic or the Arctic generally," said Peter De Groot of Queen's University in Kingston, Ont.
Estimating bear populations has become increasingly controversial.
Most scientists suggest that bears are coming under increasing pressure as climate change melts the ice they use as a hunting platform. The U.S. Fish and Wildlife Service is considering whether to declare the bears an endangered species.
But guiding sport hunters is a lucrative business for some Inuit and they have long maintained they see plenty of bears out on the land.
Lack of information
Scientists depend on expensive population surveys conducted by tranquilizing bears that have been tracked by air.
Surveying Canada's 13 bear populations through this method can cost more than $2 million per region, so counts only take place every 13 years or so.
That means wildlife managers who set hunting limits and scientists trying to understand how the changing Arctic is affecting its largest predator have to make decisions on increasingly doubtful data.
"There's a hell of a lack of information and to me, the harvesting regime gets increasingly incorrect," De Groot said. "You can't take data that's 10 years old in a dynamic system that's subject to change like the melting of ice and set up harvesting regimes."
He's hoping the procedure developed by a European-based company called Wildtrack could help end the dispute.
'As individual as fingerprints'
Wildtrack uses the photographs taken in the field to measure the distances and angles between the bear's five toes and its toe and heel footpads.
"They are probably as individual as fingerprints," said Suzanne Sprajcar of SAS, the company that developed the software for the program.
Footprint surveys, however, require only a camera and an Inuit bear tracker. The cost is about one-quarter of a full "mark-and-capture" survey.
"That's the strength of the Inuit," said De Groot, who works in the M'Clintock Channel region near the Nunavut community of Gjoa Haven. "You give them a hunting knife and a can of gas and in two weeks they'll come back with whatever you want."
Such surveys could be done almost yearly, using mostly local resources.
But first, De Groot's team must first find enough fresh, clear footprints from bears of known age and sex in order to have something to compare to those from unknown bears. Over the next few months, he plans to develop that reference in Churchill, Man., where bears — even known individuals — are more commonly handled.
De Groot's work will also gather genetic information using hair samples gleaned from barbed wire strung up along chunks of seal meat.
The system will also involve local Inuit as expert bear trackers and data gatherers. Many hunters now claim they can already tell a bear's age and sex from its footprint, and De Groot said the Wildtrack system will give local people a role to play in the science that determines how their wildlife is managed.
"We're about inclusivity," he said. "Before it was quite paternalistic — the men in the white coats show up and collect all this data and put it into their black box computers and out it comes."