While driving the interstate during the holidays, I spotted a strange white blob atop a road sign.
The sign was of course, a thin sheet of metal, and couldn’t support a pile of snow. So what was that pile of white on top of the sign?
As I sped past at 70 mph, I realized I’d just buzzed by one of Wisconsin’s most exciting winter visitors. Bubo scandiacus, or in other words, a snowy owl.
Snowy owls are one of the few diurnal owls.These two-foot-long, four-pound wonders look as fluffy as the white stuff they’re named after.
Snow owls, or “snowies” as the birds are often affectionately called, don’t nest in Wisconsin. They breed from Ontario to Alaska, preferring the wide-open tundra to forests and dairy farms.
But their wintering here is just fine. Though snowy owls tend to be solitary during the non-breeding season, they move en masse in natural events that are called “irruptions.” They’re coaxed south into Wisconsin for a number of complex biological reasons.
Ryan Brady, an ornithologist with the Wisconsin Department of Natural Resources, has been keeping tabs on Wisconsin snowy owls for years. Some years the birds are nowhere to be found.
But this year? Be careful where you set your snowshoes.
“We had big flights in 2011-12, 2013-14, and 2014-15,” Brady said of snowy owl numbers in Wisconsin. “All were reasonably comparable in terms of numbers here in Wisconsin, though 2014-15 was the largest total — mid-high 200s — by a small margin.”
So far, this year is comparable, Brady said, with 202 snowy owls having been reported across the state as of Dec 26.
Some years irruptions are driven by shortages of munchable rodents up north, a fact that drives snowy owls south, Brady said.
“Not all irruptions are created equal,” he cautioned. “The mechanism may not always be the same, but this year’s irruption appears to be the result of very successful breeding in the Arctic. We can hypothesize this based on the majority of birds seen being in juvenile plumage.”
Highway 29 creates a rather predictable range limit for the birds’ southern winter wanderings, Brady said.
“(The) Eau Claire/Highway 29 corridor is good because it’s the first area of large open habitat (tundra-like) after the birds cross the north woods headed south.” he said.
Since snowy owls are striking in appearance and people get excited about spotting them, counting them is easier than with some other bird species. Twenty years ago, the birds came and left. Now reported sightings are funneled to a website and the big white birds are leaving data trails.
“That’s not to say no one was paying attention,” Brady said. “They just didn’t attempt to tally them in any rigorous way. Of course, now we have eBird, Facebook, and other forms of communication that make us more aware and connected than ever.”
The upside of having large numbers of snowies drop in is an uptick in spirited nature watching. The downside? It may mean that the birds are sick or stressed.
“We’ve surprisingly had four to five irruptions in the 8 years, which certainly bucks the general trend of one every four to five years,” Brady said. “There have been a lot of juveniles in these irruptions, which one could definitely see as a good thing. On the other hand, if the population cycles are out of whack, perhaps due to climate change, then that would be a negative over the longterm.”
When snowy owls are reported, people take notice. Anne Geraghty, one of the Chippewa Valley’s most energetic birders, led a guided car trip early last spring in search of them.
“The Natural Resources Foundation offers a very popular series of field trips in the spring and summer and added a snowy owl trips in eastern Wisconsin in previous winters that had also proved popular,” she said.
Snowy Owls typically love shorelines, not only because the habitat mirrors the open tundra but because food sources are more readily available.
“The Lake Michigan shore is good because the birds don’t want to cross the vast open water of the lake and thus are funneled down the shoreline,” Brady said. “The breakwalls and other structures in the harbors there provide good places to roost and any open water hosts ducks, mink, muskrats and other prey.”
Away from the Great Lakes, snowy owls are drawn to agriculture land. Searching for white lumpy birds in a lumpy white landscape might be problematic, but Geraghty offers some tips.
“I usually have the best luck finding them late in the day as they get up on hunting perches,” she said. “Sometimes they’ll pick a roost spot on the top of a building, silo, or hay bale to spend the day and you can find them easily. But often they’re nestled up against a fence row or just out in the middle of a big white field and they’re very hard to spot.”
In evenings, Geraghty said, snowy owls often get up on hunting perches such as utility poles and are easier to spot.
“Dawn can be a good time to look, too, if you’re an early riser,” she said.
Drive where you can see fence posts and silos in Dunn, Chippewa, Clark or Marathon counties in January through March and you’ll likely find “lumps of snow” that turn their heads to stare at you like you’re a lemming sandwich, or maybe a pigeon pot pie.
“I found a snowy owl last week on the Chippewa Falls (Christmas Bird Count),” said Geraghty. “It was right near the road, so I was able to take a nice photograph by stopping far enough back and staying in my car so as to not flush the bird”
I personally spotted a roadkill snowy along Highway 29 in Chippewa County around Thanksgiving. Geraghty spotted another, just outside Eau Claire, along Highway 12.
“They unfortunately have little experience with cars,” she said. “Open (road) shoulders are good hunting grounds with nice perches, but are hazardous as well.”
Do not disturb
Snowy owls love open terrain and are often spotted at airports. A few weeks ago, employees at Wittman Regional Airport in Oshkosh discovered a snowy owl on airport property and, citing it as a potential site hazard, exterminated it. That act led to an immediate and robust response from nature lovers around the state, and airport officials have since changed their policy and will now use non-lethal methods.
Nature photographers can also harm northern owls by approaching them too aggressively. In winter, energy resources are critical to birds, and an owl that is disturbed by humans expends energy that could be applied to hunting or digestion. If food is scarce, that could tax the bird’s reserves.
Last year a thoughtless photographer was observed repeatedly flushing a snowy owl in Dunn County. For that reason birders across the state are secretive about reporting the exact locations of owls.
In 2013, a northern hawk owl named “Lars” was a big hit with nature lovers and photographers after he spent the entire winter along Lars Road south of Eau Claire. However, one misguided individual took it upon himself to feed the owl store-bought mice. That’s trouble because the mice may carry harmful parasites or germs, and a wild owl could become over-accustomed to human contact and easy meals.
Tips for respectfully viewing winter owls and ongoing tracking of snowy owls can be found at http://dnr.wi.gov/topic/WildlifeHabitat/SnowyOwls.html.
Betchkal is a bird expert, videographer and writer who lives in Eau Claire.