JWM: Helicopter skiing reduces caribou range in British Columbia

Heli-skiing in the backcountry of south-central British Columbia may be driving down numbers of southern mountain caribou already facing a growing litany of existential threats from their last remote sanctuaries.

“More than half of the herds have been extirpated in recent years,” and mostly in the southern end of the range, said TWS member Michael Noonan, an assistant professor at the University of British Columbia Okanagan.

But new research reveals that much of prime heli-skiing territory doesn’t overlap with the winter habitat of southern mountain caribou (Rangifer tarandus caribou), pointing to a potential pathway to reduce pressure that skiers inadvertently cause. 

Southern mountain caribou have declined precipitously in recent decades throughout their range, which includes much of the southern two-thirds of British Columbia and the Alberta Rocky Mountains. There are various reasons for this drop, but the main problem relates to forestry practices that have opened up territory for white-tailed deer (Odocoileus virginianus) and moose (Alces alces). An influx of these ungulates in areas that were formerly old-growth forest has led to an increase in predators like gray wolves (Canis lupus), which also incidentally prey on caribou. The loss of old-growth forest has also led to a decline in lichen forage. Southern mountain caribou have been listed as endangered under Canada’s federal Species at Risk Act since 2002.

Backcountry problems

Meanwhile, in interior British Columbia, heli-skiing operations occur within a vast area of public land, about 40,000 square kilometers of which overlaps closely with caribou habitat. Caribou in the Monashee and Selkirk mountain ranges have declined at a faster rate than populations farther north. But caribou migrate to higher elevation areas, which have deeper snow, during the winter to get away from the competition from other ungulates and the predators they attract. “Those are just the type of habitats that make for great skiing,” Noonan said.

Noonan and his colleague Ryan Gill, an independent wildlife consultant, wanted to see what effect backcountry heli-skiing was having on caribou. A master’s student had conducted unpublished thesis work in 2007 showing that caribou living in areas with more heli-skiing and snowmobiling had higher stress levels than those in areas without. But little research had been done since then, and the heli-skiing industry often argued that their activities had little effect on caribou, despite concern from the provincial government. “They’ve been at loggerheads on this issue for decades,” Gill said.

Researchers had been monitoring GPS-collared southern mountain caribou for years throughout the Columbia and Rocky mountains. Then, in the winter of 2020-2021, quarantine restrictions during the COVID-19 pandemic suddenly stopped skiing in the area.

Caribou and the anthropause

In a study published in 2023 in Animal Conservation, Noonan, Gill and their colleagues looked at four winters starting in 2018-2019 and finishing in 2021-2022, encompassing the time before, during and after the quarantine. “COVID provided us an opportunity to see what was happening when humans were removed from the landscape while everything else was held constant,” Gill said.

They found that southern mountain caribou responded to the lack of recreationists in the interior of British Columbia. “We saw caribou home ranges were much bigger—almost twice as big during the period where skiers were absent,” Gill said. But when the helicopters and skiers returned in the winter of 2021-2022, the caribou range contracted to pre-pandemic levels once again. 

But the researchers still couldn’t tell directly where those effects were occurring. In a study published recently in the Journal of Wildlife Management, Gill, Noonan and their colleagues overlaid GPS tracking collar data of caribou with information they pulled from Strava, a phone- or watch-based fitness tracking application. Strava uploads the location data taken from publicly available accounts onto an anonymous heat map that shows user activity. Heli-skiing involves helicopter drop-offs to remote mountain peaks in the backcountry for skiers who pay top dollar in search of “champagne powder” and fresh tracks. “These [areas] are so remote that there’s no way that it was someone going for a jog in the winter—we’re pretty confident these were skiers,” Gill said.

The team modeled the presence of skiers and compared it to caribou presence. They identified about 400 square kilometers of conflict area often used by both caribou and skiers. This was out of 3,116 square kilometers of area they identified as suitable for heli-skiing.

“Only a small percentage of the total area is a high-conflict area,” Gill said.

This is good news, as it presents plenty of opportunity for skiers to use the backcountry area with less effect on caribou. However, it’s difficult to know how amenable the industry will be to taking these findings into consideration—Noonan said he and his team know nothing about the logistics of the industry in terms of optimal ski areas, helicopter staging locations or backcountry lodging. But there are more than 20 operators in the area, each of which has different practices.

But these two studies have opened more dialogue about possible measures to prevent unnecessary interactions between skiers and caribou. “It’s started to move the needle, I think, on this issue,” Noonan said.

While recreation like skiing definitely has a much lesser effect than logging and predator infusion, Gill said that the only southern mountain caribou herds that are stable are due to wildlife managers taking as many measures as they can to boost numbers. This includes habitat restoration, maternity pens, supplemental feeding, predator control and moose suppression.

In order for the population to improve in the heli-skiing areas, Gill said it’s important to consider all activities affecting caribou, including recreation.

This article features research that was published in a TWS peer-reviewed journal. Individual online access to all TWS journal articles is a benefit of membership. Join TWS now to read the latest in wildlife research.