The Valhalla Wilderness Society says that snowmobilers may be creating "sidewalks" in the snow that give wolves easier access to the threatened species
“Predators have a sidewalk up to that habitat,” said Craig Pettitt, whose concerns arise from a recent B.C. Ministry of Environment report which says there is rampant snowmobile use in the critical winter habitat of the south Purcells herd, near Cranbrook.
Mountain caribou, an ecotype of woodland caribou (Rangifer tarandus caribou) is a threatened species in southeastern British Columbia, and it is believed that the south Purcell’s herd’s numbers have dropped to 15.
According to the Ministry of Environment website, government has closed some areas to snowmobile use where mountain caribou are found since 1999 to support population recovery, but Pettitt says most of the closures are only partial, and allow snowmobiles to use roads and cutblocks in surrounding areas.
“This allows the machines to pack down the snow over extensive areas, and the packed snow gives wolves easy access to caribou areas,” Pettitt said, adding that many of the closures are also voluntary.
In January and February — prime snowmobiling months — pregnant caribou cows could be driven from their territory by snowmobilers during a crucial time for the herd, says Pettitt.
Planned increases to the legally restricted areas are expected to help protect the incoming herd, but a lot of the best feeding territory for caribou hasn’t been protected, Pettitt says, with snowmobilers favouring the same high slopes where tree lichen grows — a nearly-exclusive staple in the mountain caribou’s diet.
In 15 research flights over the south Purcells from 2008 through 2010, ministry researchers recorded snowmobile activity in 71 restricted basins, according to the report titled Winter Recreational Activities in Mountain Caribou Habitat.
The report comes as the Ministry of Environment is planning to bring 40 Mountain caribou from Dease Lake in northwestern B.C. to the south Purcell Mountains to boost the south Purcell herd. The hope is that the new animals brought from the north will give the Purcell herd a chance at long-term survival.
Twenty caribou are scheduled to arrive by truck in mid-March, followed by another 20 in 2013, said Steve Gordon, strategic resource manager, Ministry of Forests, Lands and Natural Resource Operations, which is leading the $200,000 transfer.
Local and provincial snowmobile associations have been cooperative, he said. “The clubs have stepped up in terms of their stewardship.”
However, the ministry report said that in spite of cooperation by the Cranbrook Snowmobile Club, which posted closure signage and promoted awareness among its members, the problem of snowmobilers using restricted areas remains.
Conservation officers will issue a ticket to offenders who don’t comply, and planned aerial surveillance by the ministry should help convince snowmobilers to stick to the permitted areas, Gordon said.
As well, some of the south Purcells herd will be outfitted with GPS collars which will notify researchers if they start shifting into habitat that isn’t protected, or if they get killed by predators such as wolves — which could face culls if they start killing the new caribou. Some wolves will also be fitted with GPS collars to monitor the situation.
“We’ll know where [the caribou] are going,” Gordon said in reference to the GPS collars, noting that changes can be made to the boundaries of any restricted areas if “overlap” with snowmobilers becomes a problem.
The province’s population of mountain caribou has dropped from around 2,500 before 1995, to around 1,850 today, due to a loss of habitat, food supply, and booming wolf and cougar populations.