Snowy owls return to Prairies for winter with new status as threatened species

Every year, snowy owls spread their wings and migrate down to the Prairies, where they enjoy access to plenty of rodent prey in vast open spaces.

But this year's migration is the first of its kind, marked by the recent classification of snowy owls as a threatened species.

That designation was announced in May by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC), which assesses the at-risk status of native species and provides recommendations to the federal government.

Louise Blight, an adjunct associate professor at the University of Victoria's School of Environmental Studies and co-chair of the COSEWIC birds specialist sub-committee, said the decision to designate snowy owls as a threatened species was not made lightly. But, she said, their population has declined about 40 per cent in the past 24 years.

Snowy owls face many challenges, including habitat loss in their Arctic nesting grounds due to climate change, Blight said. Warming temperatures are melting sea ice, reducing platforms for the owls to sit on when hunting.

Snowy owls are also impacted by avian influenza — both contracting it and losing winter prey to the virus, said Blight. There have been 15 cases of avian influenza found in snowy owls in Canada since 2021, according to data compiled by the Canadian Food Inspection Agency.

Snowy owls face even more challenges when they embark on their lengthy migrations south. In their wintering grounds, they can be hit by vehicles, electrocuted by power lines, tangled in human structures, and become poisoned after eating prey that has been exposed to rodenticide.

Colin Weir, managing director of the Alberta Birds of Prey Foundation wildlife rehabilitation centre in Coaldale, has dealt with raptors affected by all of those.

"A lot of times when snowy owls come down from the Arctic ... they're coming into new areas with lots of man-made hazards around," Weir said.

The centre cares for injured birds from across Canada, and is currently home to two snowy owls that ended up unable to be released after being hit by cars.

"The thing to remember about roadways is they have ditches, which collect a lot of moisture and attract a lot of ground rodents," Weir said. "So, that's why birds get hit by cars. The roadside ditches are basically like buffet restaurants to them."

Weir said the busiest time for bird collisions in Alberta is May to September, as most migratory birds of prey are back from overwintering farther south at that time, but that's not the case for snowy owls.

"Just watching for wildlife in general is probably the number one thing," Weir said. "Not only for the safety of the creatures themselves, but just for people's own personal safety as well."

Snowy owls can be found in every Canadian province following their winter migration. NatureCounts, a biodiversity data platform operated by Birds Canada, estimates there are 15,000 snowy owls in the country — more than half of the estimated global population of 29,000.