Around the full moon each winter month, a different kind of creature gathers on the open slopes at Sunlight Mountain Resort.

Sometimes in packs, other times just one or two at a time, they’ll make their way in a steady stream up the ski mountain to the top, shed their skins, then ski back down.

Oftentimes they’ll skin up again and turn around for a repeat run.

These creatures are cathemeral, too — and can be found out in the daytime all week long, at least for as long as the snow lasts.

Welcome to the uphill ski community, which has built a culture all its own among winter recreation enthusiasts up and down the Roaring Fork Valley, and in ski resort communities across the country.

“We’ve definitely seen, just in the past three seasons really, a huge uptick in uphill traffic,” said Travis Baptiste, group sales and events manager for Sunlight.

In response, Sunlight began designating certain uphill routes to control the uphill flow and prevent conflicts with downhill skiers. A special $10-per-day or $50 season pass is also now required for uphill access. Regular season pass holders get uphill access at no extra charge.

“It’s really cool to see so many season pass holders mixing it up with some uphilling and regular lift access on a given day,” Baptiste said. “They could ride the lifts all day if they want, but they’re just out here for fitness, which I love to see.”

Uphill skiing used to be limited to the subset of alpine skiers known as telemark, or tele skiers. Telemark style uses a special cross-country ski type of cable binding that keeps the heel free and allows for uphill climbing.

But with the advent of modern alpine touring (AT), or randonee gear, which allows the skier to free the heel for climbing then clip in for a traditional alpine ski descent, the sport of uphilling at maintained ski areas, and out in the backcountry, has grown.

The ascent is accomplished with the use of special climbing “skins,” which have a sticky substance on one side that adheres to the ski, and a type of nylon or natural mohair material, or a blend, on the bottom to provide the traction to climb uphill.

During the height of the pandemic, even more people were attracted to uphill skiing as a way to get outdoors for some exercise, so Sunlight decided to go all in and embrace it.

For a second straight season, the ski area is hosting a monthly Moonlight Race Series, a combo uphill, downhill and cross-country race for recreational and competitive skiers alike.

A corresponding Skinning 101 Clinic is offered to teach the basics of uphilling technique, taught by Nathan Boyer of Cripple Creek Backcountry in Carbondale.

Before taking up backcountry skiing, it’s a good idea to learn how to go uphill on the groomed or packed-out slopes of a maintained ski area before heading out into the forest.

The next moonlight event and clinic coincides with St. Patrick’s Day on March 17, when there will be some extra aprés ski festivities on tap, Baptiste said.

During the Feb. 17 moonlight event, Baptiste estimated there were probably 100 or so uphillers between the race event and an informal group of uphill skiers who show up every Thursday evening after the lifts close.

Among them were John Christensen and Quinn Harnett of Glenwood Springs, who did the moonlight trek that Thursday night and were back on the mountain again Friday morning for a few more laps.

Christensen said he picked up the sport during the pandemic when he decided to buy an AT setup for his skis.

“When it comes to fitness, it’s great for the winter,” said Christensen, who is also a runner. “I get really tired of running all the time, and the community that we’ve built around uphilling is fun. Every Thursday night we have a big group that goes up, then we all go have some chili or something together afterwards.”

Harnett said uphilling was a way to connect with his new co-workers when he moved to Glenwood three seasons ago.

“It became a regular weekly thing to do as a group, and it was just a chance for me to get to know people better,” he said.

Chloe Couvreux of Redstone introduced her pre-teen sons Sky and Tao to uphill skinning during COVID.

“We run as a family, so this is winter cross-training for us,” she said while stripping the skins off her skis outside the warming hut at the top of Sunlight on a recent bluebird morning.

Her husband, Brendan, is one of the ski patrollers at Sunlight, so the family will often come to do an uphill run and meet him for a downhill run or two.

“I love that it’s self-power to the top and then you can ski down without ever getting on the lift,” Couvreux said.

“It’s good for the grit,” adds Sky. “It’s also really tiring.”

Friends Lynsey Pulliam and Nicole Konechne of Glenwood Springs have been training for the Power of Two, the shorter version of the Audi Power of Four ski mountaineering race that takes place Saturday in Aspen.

“We’re usually out here two or three times a week,” said Pulliam, adding that has included a 4:30 a.m. training run on Mondays and Wednesdays for several weeks leading up to the event.

“I like the workout that it provides, and learning some of the technique that you have to have when you get onto the steeper stuff,” she said.

Learning how to properly use the built-in stilts to lift the heel for climbing is a big part of making the climb comfortable, she said.

“We’re earning our turns, so that in itself is fun,” Pulliam said of the descent that awaits them at the top.

Konechne said she started uphilling when she was telemark skiing, and progressed as the equipment got better.

“It’s just another fun way to be outside and on the snow,” she said.

Baptiste recalls how the sport has grown over the last 10 years or so, and how the social aspect of it also migrated downvalley from Aspen. A Friday Morning Uphill Breakfast Club at Buttermilk has been going for several years.

“It’s definitely a culture thing that bled down into the Glenwood where there wasn’t a big uphill crowd aside from the tele skiers,” Baptiste said.

The Moonlight Series is more of a community event than a competitive race, he said.

“Afterwards, it’s fun to see people just sitting around having a drink and networking with some like-minded people,” he said.

For anyone on the fence about giving it a try, Christensen advised, “just get whatever inexpensive setup you can and do it. People should give themselves more credit and just try it. We’re all pretty welcoming, and it’s just a good time.”

Senior Reporter/Managing Editor John Stroud can be reached at 970-384-9160 or jstroud@postindependent.com.