Snowy owl
Two hundred eighty snowy owls have been documented in Wisconsin this winter, the highest total on record, according to state birding experts.

The previous high was 253 in the winter of 2013-'14, said Ryan Brady, bird monitoring coordinator with the Department of Natural Resources.

In fact, more than 200 of the big, white owls have migrated to Wisconsin in three of the last five years, all historically large movements.

"We've gotten pretty spoiled in recent years," said Brady.

By teasing through observations entered on eBird, an Internet-based bird reporting tool hosted by the Cornell Lab of Ornithology, Brady is able to differentiate sightings of individual animals.

In addition to the high number of birds recorded, snowies have been sighted this winter in 67 of the state's 72 counties. Buffalo, Florence, Forest, Menominee and Walworth are the counties without a snowy sighting.

"The geographic distribution has been remarkable," Brady said. "From Kenosha to Ashland and every spot in between, this winter it wouldn't have surprised me to get a snowy owl observation, even from heavily forested areas."

It's possible larger irruptions of snowies occurred historically but weren't recorded or were too difficult to estimate with available technology.

Snowy owls are the heaviest owl (3 to 6 pounds) in North America, stand 2 feet tall and have 5-foot wingspans.

They have white plumage, often with black barring, yellow eyes and large, feather-covered feet.

The species nests worldwide on the tundra above the Arctic Circle. During a typical winter some remain close to their breeding areas while others head into southern Canada and the northern United States, according to the DNR.

At least a handful of snowy owls reach Wisconsin each year. And intermittently, large numbers move into the state in events known as an "irruptions."

This year was termed a "significant" snowy irruption, according to birding experts. Many hundreds of birds were reported across the Midwest and East. Numerous sightings also were recorded in the Northwest; several snowy owls were even sighted as far south as Oklahoma and Texas.

The largest movements of snowies into Wisconsin have been linked to years with high lemming abundance (the owl's key food source on the breeding grounds) and high production of young owls.

In fact, most of the snowies seen in Wisconsin are juveniles, Brady said.

The reasons behind recent irruptions aren't clear, although some researchers have suggested changes in precipitation patterns have allowed higher snowy owl production in areas of northern Canada. In addition, survivors of the large 2013 and 2014 year classes are now breeding adults, which helped produce birds last summer.

Snowy owls favor open areas for their winter territories, including lakefronts, prairies and farm fields.

According to Wisconsin eBird data, snowy owl hotspots include agricultural areas of Columbia County, the Buena Vista Wildlife Area, the Highway 29 corridor from central to western Wisconsin, the Fox Valley from Green Bay through Freedom to Appleton, the Ashland area, and various points along Lake Michigan, including Milwaukee.

Unfortunately, several dozen snowies have been found dead or injured in Wisconsin this winter. Most were killed as a result of vehicle collisions, Brady said.

In a handful of cases, including an owl found in southeastern Wisconsin and rehabilitated at the Wisconsin Humane Society in Milwaukee, the injured birds were returned to the wild.

By mid-February, the owls in Wisconsin have typically settled into a territory and move only short distances to hunt and roost.

In March, some - especially adults intent on establishing a breeding territory in the Arctic - will begin to migrate north.

But since most of the snowies in Wisconsin are juveniles, Brady said some of the birds would likely be in the state for more than another month. Research indicates snowies don't breed until age 2.

Despite the high number of sightings of snowy owls in recent years, public fascination with the birds remains high.

Brady related a story of a truck driver who has worked in Grant County for 25 years and saw his first snowy owl this month. The man called Brady to report the sighting.

"The excitement in his voice reminded me once again how people connect with these birds," Brady said. "It's pretty cool and the kind of thing that's so helpful with our broader conservation efforts."

Four owls tagged in Wisconsin: Four snowy owls in Wisconsin this winter were fitted with GPS transmitters as part of Operation SNOWstorm.

The sophisticated solar-powered units collect data every 30 minutes and allow researchers to precisely track the birds' movements.

The devices cost about $3,000 each plus several hundred dollars for a cellular data plan.

Thanks to special fundraising efforts in Wisconsin this winter, five transmitters were purchased for owl research in the state.

The Natural Resources Foundation of Wisconsin, Madison Audubon, Wisconsin Public Service Foundation and Wisconsin Society for Ornithology provided the funding for the units.

The four owls are named Arlington, Austin, Badger and Bancroft. The movements of each can be viewed on the Operation SNOWstorm website.

The fifth transmitter likely will be fitted on a snowy owl during the next incursion, perhaps in December, according to David Brinker, co-founder of Project SNOWstorm. Twenty-one owls were fitted with transmitters across the nation this year, one fewer than in the project's initial year.