A government study warns that off-highway vehicles have become the main source of human impact in a large park planned for Alberta’s southern Rocky Mountain foothills and threaten the area’s fragile environment.
The NDP government is deciding what will be allowed in Castle Wildland Provincial Park and Castle Provincial Park, a vast area covering 1,000 square kilometres of mountains and valleys that are home to 180 species of plants and animals considered endangered or threatened.
“While the footprints of historical disturbances from forestry and other industrial activities are a significant part of the landscape of the Castle region, (trails) used primarily for recreation have been a dominant feature of land use in recent years,” the study concludes.
The report released late last month by the province’s environmental monitoring department draws on more than 150 peer-reviewed scientific studies.
READ MORE: Scientists back Alberta plan to ban off-highway vehicles from Castle park
It finds uncertainties remain, but details strong evidence of heavy and growing off-highway vehicle use in the area along with related impacts.
It lists at least 1,700 kilometres of trails, which far outstrip logging or energy roads. The region averages a trail density at least twice as high as other Alberta provincial and national parks.
The study found more than 1,600 crossings on streams, almost all of which are headwaters for rivers. Some streams have up to 10 crossings per kilometre, few of them bridged.
It also notes that most human-caused grizzly deaths in Alberta and British Columbia happen within 500 metres of a road or 200 metres of a trail. Trail density in the parks already exceeds the level at which grizzly populations decline, it says.
Stream crossings, which increase sediment in water, damage trout spawning. The report quotes a Colorado study that found three times as much sediment in streams crossed by off-highway vehicles as in forestry road crossings.
“It is highly likely that sediment production is significantly higher than observed in the Colorado study.”
The report notes that trails and roads increase soil erosion and compaction, reduce plant cover and biodiversity, change the species mix and cut up habitat.
READ MORE: Alberta to expand Castle area parks, phase out off-highway vehicles
Gary Clark, president of a local off-highway vehicle users group, called the report a foregone conclusion.
“It seems to me they’re trying their hardest to legitimize their decision on what’s happening here,” he said Wednesday.
Clark said banning the vehicles won’t change the fact that the trails exist. Vehicle owners have spent thousands of dollars upgrading and maintaining trails, he added.
The Castle landscape supports forestry, oil and gas and agriculture as well as skiing, hiking and horseback riding.
It is also a popular off-highway vehicle destination. The study points out the general area was voted favourite overall by readers of RiderWest magazine last year.
In their draft management plans for the parks, the New Democrats have proposed banning motorized recreation.
Scientific consensus remains against such vehicles. Last spring, 57 scientists sent an open letter to Alberta Environment Minister Shannon Phillips urging the province to stand by a ban.
READ MORE: Protesters rally against Alberta’s proposed phase-out of off-highway vehicles in Castle area
Pat Stier, who represents the area as a legislature member for the Opposition United Conservatives, said off-highway vehicles have a long history in the area and some trails for them should remain.
“We’ve always been advocating to find a balanced approach and that would include more enforcement and more administration,” he said. “We think there’s still an opportunity to work with these groups.”
He said his newly formed party has yet to develop an official policy on the issue.
The final parks plans are expected in the spring.