An Unexpected Baby Boom Is Bringing Snowy Owls South This Winter

Since late October, something unexpected has been happening: Snowy Owls have been showing up all over the place. They’ve appeared across the Canadian prairies and Maritimes and in the Great Lakes region, particularly around Ontario, Michigan, and Wisconsin. Sightings have rapidly increased throughout November and December, with the striking white raptors reported in areas where they’ve been largely or entirely absent in recent years, including British Columbia, Washington, New York, Ohio, Iowa, Kentucky, and South Dakota.  

Their appearance in numbers has taken Snowy Owl experts by surprise. “We expected it was going to be a dull winter,” says Scott Weidensaul, naturalist and co-founder of Project SNOWstorm, a research project focused on the species. Weidensaul and his team hadn’t heard the reports of significant breeding that would typically precede a major southward irruption of owls. But “the Canadian Arctic is a big place,” he says. “There must have been a significant breeding event up there, because there’s a lot of baby owls coming south this fall.”

Though Snowy Owls can still catch experts off-guard, scientific knowledge of the species has come a long way in the past decade. That’s thanks in large part to Project SNOWstorm (whose name refers to SNOW, the banding code scientists use for the species). Over the past decade, Weidensaul and his colleagues have shaken up conventional wisdom about Snowy Owl populations and movements, using these insights to help shape conservation efforts for the species.

The project arose from an irruption event far more intense than the one playing out now. In the winter of 2013-2014, Snowy Owls flooded into the Northeast and the Great Lakes region in numbers likely not seen in a century, appearing as far south as Florida and Bermuda. Weidensaul and other owl enthusiasts realized they had a rare opportunity to study the birds close to home. “None of us are going to live long enough to see something like this again,” Weidensaul recalls a friend telling him. “We decided to get as much information from that massive irruption as we could.”

They quickly set up Project SNOWstorm, recruited volunteers, and raised enough funding to outfit 22 birds with solar-powered transmitters. Since then, the nonprofit has tracked more than 115 birds in 17 states, producing what the team believes is the world’s largest dataset on local and migration movements of Snowy Owls.

The researchers also gather health data when they capture birds for tagging, and what they’ve found has helped to overturn a longstanding myth about what’s behind Snowy irruptions. “For many, many years, people assumed that what drove these owls south was hunger, that these were starving owls that couldn’t find anything to eat in the Arctic,” Weidensaul says. In fact, influxes consist primarily of healthy, young Snowy Owls born the previous summer in the Arctic—not a response to food shortages, but a result of owl baby booms fueled by bountiful prey in the form of lemmings.  

Those young birds might come south in search of a suitable place to live out their first winter while older, more dominant individuals occupy prime Arctic habitat, says Rebecca McCabe, research biologist at Hawk Mountain Sanctuary and a member of the International Snowy Owl Working Group (ISOWG), both of which collaborate closely with Project SNOWstorm. Not all birds that come south are young, though; certain adults come south every year, and others every other year. “We see a lot of variation among individuals,” McCabe says.

The team’s findings have also raised conservation concerns about the species. Snowy Owls are facing increasing and significant risks from climate change, rodenticides, mercury poisoning, avian influenza, and vehicle strikes. “Anything that we can do to protect these birds and their breeding grounds, and improve their year-to-year breeding success, is going to be important,” Weidensaul said.

That’s especially true because, as Project SNOWstorm’s data have helped to show, there are far fewer Snowy Owls than was previously thought. In 2004, scientists estimated the global population could be as high as 290,000 owls. Satellite tracking, by Project SNOWstorm and other groups, helped refine that number by showing just how nomadic this species can be. “We didn’t realize that the snowy owls that are breeding in central Canada one year may be in Greenland the next year,” Weidensaul says. A global status assessment of the population, released in 2025 by the ISOWG with significant support from Project SNOWstorm, puts the population between 14,000 and 28,000 breeding-age adults.

Helping to protect the birds by sharing their findings with the public and decision makers is a big part of the SNOWstorm team’s work, Weidensaul says. Their findings have proven useful at airports, for example, where Snowy Owls often spend the winter, posing a risk for the birds and for airplane passengers.

The tracking data are also pointing the team toward areas of the Arctic that are especially important for the owls and may need protection. Earlier this year, Project SNOWstorm began analyzing summer movement data with the goal of predicting where Snowy Owls choose to nest year-to-year in the Canadian Arctic. The analysis has already identified places where unusually large numbers of the birds congregate in summer. “This is our glimpse into that world, and to try to better understand what these owls need in this really important part of their range.” 

As for their wintering areas, Project SNOWstorm will be watching where their owls with transmitters might appear over the next few months. The birds spotted in the south are mostly juveniles so far; adults typically follow later. Snowy Owls are generalists in the winter, eating small mammals like muskrats and rabbits, and water birds like loons, ducks, and grebes, so they’re likely to show up in tundra-like farm fields or by bodies of water. Some birds hunker down in a wintering area, while others move around, particularly as they ready for spring migration. Last year, Project SNOWstorm tracked Snowy Owls heading back to the Arctic when milder weather hit in March, but a couple of owls were in Ontario and Quebec as late as May.

Wherever Snowies show up, it’s important for birders and photographers to give them space and take caution not to disturb them, experts say. If an owl stares at you, bobs its head repeatedly, or otherwise responds to your presence, you’re too close and should immediately give it more space.

After all, Snowy Owls face enough threats already, and this year’s surprise irruption is a gift not to be squandered.