The Clark’s nutcracker, I surmised after observing one in an Aspen tree last winter furiously pecking at a seed, is a determined bird. His sharp beak matched the black wingtips on his pearl gray body, and white, spectacle-like eye rings seemed to amplify his diligence. The bird is the size of a jay, but on this frigid morning in Aspen, Colo., he had puffed out his feathers for warmth in comically plump style.
“Every day’s mission for all the birds that stay here in the winter is to get the calories that they need,” said Rebecca Weiss, my birding guide and the author of “Birds of Aspen and the Roaring Fork Valley,” who leads birding excursions year-round for the conservation and education nonprofit Aspen Center for Environmental Studies.
Most people associate birds and birding with warmer weather, which the animals often chase. But many endemic species stay and, here in the Rocky Mountains, migrants arrive from the more punishing north.
In winter, wildlife watchers have the advantage of clearer sightlines after the deciduous leaves have dropped. Birds and other animals often stand out against the white backdrop, making them easier to spot. And even if you can’t see them, their tracks let you know they’re around.
More ideas to embrace the cold:
8 New Hotels for Winter Enthusiasts in the U.S. and Europe: New and reimagined hotels in New England, the Alps and beyond offer stylish accommodations near the snow.
The Quiet Thrill of Winter Wildlife Viewing: In Colorado’s Rockies, birds and other animals stand out against the snow, and even if you can’t see them, their tracks let you know they’re around.
At a Club Med Ski Resort, Learning to Love the Apéro: Will the company’s all-inclusive approach work in the North American market? An avid skier puts Québec’s Massif de Charlevoix to the test.
Taking Back the Mountains: Big resorts are crowded, pricey and exclusive. But some skiers and snowboarders are trying to reclaim their sports by building a culture that is more inclusive and sustainable.
Making the Slopes Fun From Day 1: When it comes to designing terrain and the learning experience, resorts have finally started thinking about beginners.
New Ski Lifts Changing U.S. Slopes This Winter: A flurry of construction at major ski resorts has led to a high number of notable new chairlifts and gondolas opening this season.
I consider myself a winter obsessive enamored with the transformative effects of snow on the land and the distinct joys of sports that involve sliding on snow and ice. But other than knowing that bears hibernate in winter, I had no idea what the animals we associate with the mountains do in winter. To find out, I broke up a ski trip to Aspen last February to take two different outings with ACES guides to look for animals, or at least signs of them.
Birding in winter
Snow-covered landscapes aren’t just a challenge for animals seeking food and shelter, but for their fans. Dressing for the patience required of birding, which usually involves standing still for periods of time to keep from spooking the quarry, requires extra thermal layering.
Ms. Weiss, the birding guide, modeled the look in a long down coat and thick-soled Sorel boots when we met near Snowmass Village, about nine miles west of Aspen, to begin our four-stop tour of different area habitats. (Normally, she holds her tours, which cost $25, at Hallam Lake, a 25-acre nature preserve near downtown Aspen, which was under construction last winter, encouraging us to explore elsewhere.)
At Brush Creek near Snowmass, we spotted the Clark’s nutcracker along with three kinds of jays — the Steller’s, Woodhouse’s scrub-jay and the pinyon — and large flocks of chatty, yellow-streaked pine siskins. For beginning birders, fewer species in winter and the tendency of some to flock together, like cedar waxwings and red crossbills, make it easier to spot and remember them.
A coyote walking the freshly groomed cross-country ski trails greeted us at the nearby Snowmass Club Golf Course, where we scanned a pond for ring-necked ducks, a diving duck with distinctive tattoo-like white, black and gray bills. They were sharing the ice flows with Crayola-bright mallards with vivid orange legs and velvet green heads.
“Ducks are in breeding plumage in winter, so they are at their finest,” Ms. Weiss said.
We searched for brown-capped rosy finches, which are endemic to Colorado and driven down from the high mountains in winter, at a collection of feeders at a private home nearby in the hills above the Aspen airport (Ms. Weiss is well known among local birders who often allow her access to their feeders). Instead, we found a flock of house finches, another of pine siskins and a diminutive downy woodpecker.
“No one knows the exact formula to get rosy finches to their feeders,” Ms. Weiss remarked of the prized birds that otherwise spend their time among 14,000-foot peaks, often called “14-ers.” “It’s incredible to see a flock of 150 gorgeous high-altitude birds that occur in Colorado and nowhere else in the world. And they’re easier to find than to scale a 14-er.”
We ended our tour at Hallam Lake, admiring the fortitude of American dippers, bathing in a snow-banked stream. The continent’s only aquatic songbird, the dark, plump, fastidious birds are considered a harbinger of clean water.
Despite the cold, nearly four hours surveying nature sped by.
“Birding is a superfun way to engage with a landscape and get to know it on a deeper, kind of meditative level,” Ms. Weiss summarized. “You can forget about everything else as you’re watching the birds treasure-hunt.”
Interpreting snow tracks
While snow muffles the terrain, obscuring the specifics of a forest under an insulating blanket, it can be a great revealer, too. Snow records the frequency of passing animals that so often we cannot see, their tracks telltale in the impressionable landscape.
Interpreting the forest habitat, ACES guides lead nature snowshoe tours departing twice daily in ski season from Aspen Mountain and the nearby Snowmass ski area ($44 if you have a lift ticket, $75 if you don’t).
I signed up for the afternoon session at Aspen Mountain, meeting my guide, James Hines, and about a dozen fellow snowshoers at the top of the Aspen gondola, where a resort photographer pointed out a pair of red crossbills, which looked a little like house finches in need of orthodonture, in the pines.
Like me, most of these snowshoers were seeking some variety in their downhill ski vacation. Several were new to snowshoeing, but quickly gained competence on the shoes provided by ACES that strapped onto our boots, keeping us from sinking more than an inch or two atop deep drifts.
Walking in snowshoes kept me warmer than birding. The trade-off, of course, was seeing fewer species up close. But Mr. Hines took a wide-angle perspective on the habitat. Leading our march on Richmond Ridge south past the ski lifts near the White River National Forest, he explained the difference between fir trees, with “flat, fragrant and friendly” needles, and spruce, which have square, spiky needles.
In the quiet backcountry we left our own oblong imprints in the snow as we puzzled out the comings and goings of animals in the forest. Encountering a meandering, single-file trail, we learned to recognize what is known as perfect stepping, in which a four-legged animal like a fox or coyote brings a hind leg to step just where a foreleg had pioneered. The right- and left-side paws land near enough to each other to leave a nearly straight line in the snow.
Distinctive four-point patterns in the snow revealed animals like squirrels and hares known as hoppers, whose small front feet tend to land before the larger back feet. A bounding animal like a weasel, whose back feet touch down so close to the front feet that its passage looks like a series of holes in the deep snow, left an arrangement of tennis-ball-size divots in a direct line.
One set of tracks — two parallel lines of small brushing marks over a foot apart — stumped us. After several wrong guesses — pine cones? a pair of mice? — our guide helped us imagine the wings of a bird beating down on a runway of snow before it got off the ground, perhaps because it was weighed down by something in its beak. I imagined a raptor with a mouse.
That is the beauty of wildlife watching in winter. We didn’t actually see a mink or a fox or a hawk with his prey, but we knew the forest was teeming with them. And the evidence was thrilling.
More tour options
Among the tours with the Adventure Group in Whistler, British Columbia, snowshoe outings explore ancient cedar forests or begin with a ride to the high country in an off-road vehicle for tramps in the forest. Tours from 129.99 Canadian dollars a person (or about $95).
Look for bison, fox and elk as well as geyser-frosted trees on guided snowshoe tours in the Old Faithful area of Yellowstone National Park with Yellowstone National Park Lodges. Roughly three-hour tours take place twice daily from mid-December to early March. Tours with snowshoe rentals cost $38 a person. The National Park Service also maintains a list of guided ski and snowshoeing operators in the area.
Keep an eye out for moose in Stowe, Vt. where the Sunrise Mountain Guides service promises snowshoeing adventures off the beaten path in and around the Green Mountain State Forest. Outings range one to three hours and cost $175 for one person or $325 for four, including snowshoes.
Combine a morning of snowshoeing in Grand Teton National Park and an afternoon in a safari-style vehicle search for bighorn sheep, elk, eagles and more on a full day tour with Jackson Hole EcoTour Adventures based in Jackson, Wyo. Tours from $315 a person, including lunch and snowshoes.
In Utah’s Wasatch Mountains, Alta Ski Area offers birding on skis to intermediate- or higher-level skiers on selective dates from December through April. Experts from Tracy Aviary in Salt Lake City guide the tour to count the birds at the ski area. Participation is free, but skiers must register and have their own ski pass or lift ticket (day tickets $154).
Go winter birding in northern Minnesota with Wildside Nature Tours, which offers a five-day trip in February out of Duluth, Minn., in search of boreal species, including owls, grouse and waterfowl, mostly from four-wheel-drive vehicles. Tours from $1,850 a person, including accommodations, ground transportation and guides.
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