Changing winds could harm polar bears
U of A research finds animals detect prey using technique called crosswind search
Changing Arctic wind patterns could be bad news for polar bears, according to a new study into how the predators use their noses to track prey.
Relying on 11 years of satellite data on 123 polar bears in Hudson Bay, University of Alberta researchers found polar bears use a technique called crosswind search to pick up the scent of their favourite prey: ringed seals.
The study sheds light on the relationship between polar bears and wind patterns, which are expected to change as the Arctic warms.
Ron Togunov, a U of A alumnus and the study’s lead author, said this is the first time crosswind hunting has been definitively observed in a mammal.
“If an animal travels downwind or upwind, it’s in the same stream of air,” he said. “Travelling crosswind … it’s constantly smelling something new and it’s more likely to detect prey.”
In some ways, the results are not surprising: Researchers have long known that bears rely on their sense of smell to hunt.
While researchers have long suspected predators use crosswinds to detect prey, the U of A study is the first time the phenomenon has been confirmed outside birds and insects.
The study merged data taken from bears equipped with GPS collars with satellite telemetry data.
“This could potentially be applied to different predators that rely on smell,” Togunov said.
Bears travel crosswind when trying to pick up a prey animal’s scent, particularly on winter nights when winds are calm, the study found.
Climate modelling predicts the Arctic will become windier as the climate changes, which Togunov said could make it harder for polar bears to smell their food.
“Because of changes that are occurring environmentally, the polar bears have a decreased body condition (and) lower fat reserves,” he said, citing sea ice loss. “This might be another thing that might lead to polar bears being in worse condition and more aggressive toward humans.”
The study, Windscapes and Olfactory Foraging in a Large Carnivore, was published this month in the journal Scientific Reports.