Achi news desk-
New research suggests that caribou numbers in western Canada, once in decline, are finally growing.
But the same paper concludes that the biggest reason for the rebound is the killing of hundreds of wolves, a policy that will likely have to continue for decades.
“If we don’t shoot wolves, given the condition of the habitat that industry and government have allowed, we will lose caribou,” said Clayton Lamb, one of 34 co-authors of a study just published in the journal Ecological Applications .
“It’s not the wolves’ fault.”
Caribou conservation is considered one of the most difficult wildlife management problems on the continent.
The animals, which have been printed on the back of Canada’s quarter since 1937, require untouched patches of hard-to-reach old growth boreal forest. Those same forests tend to be logged or drilled, creating roads and cut lines that invite in deer and moose — along with the wolves that eat anything with hooves.
Between 1991 and 2023, Caribou populations fell by half. More than a third of the herds disappeared.
Governments, scientists and First Nations have been trying for years to find ways to bring them back. Lamb and his colleagues looked at 40 herds in British Columbia and Alberta to see if anything has worked.
The paper suggests that caribou numbers have risen by 52 percent since about 2020 compared to what they would have been if nothing had been done. There are now 4,500 in the two states, about 1,500 more than there would be.
“There could be some real good news,” Lamb said. “It was surprising, in a good way.”
Industry disrupts the ranges of some herds by almost 90 per cent, and habitat restoration is the preferred solution. But it takes decades for a clearcut or cut to return to anything like old-growth status, so various gaps have been used.
Because different measures were used on different herds, the researchers could relate population trends to interventions.
Wolf sterilization did not work because it could not be done on enough of the predators.
As well as reducing the elk and deer populations that draw wolves into caribou habitat. Almost all of those populations would have to be killed, an unpopular move in rural communities and First Nations where hunting is a pastime and a necessity.
“Moose reduction is extremely controversial,” Lamb said.
Moving animals from large to small herds only helped for a season or two.
What worked was killing wolves.
“Wolf declines alone increased the growth rate of southern mountain caribou subpopulations by (about) 11 percent,” the report states.
That growth rate increased when wolf culls were combined with other measures such as feeding and corralling and protecting pregnant cows.
“Wolf reduction was the only recovery action that consistently increased population growth when applied alone,” the report states. “Combinations of wolf reductions with mother pens or supplementary feeding provided rapid growth.”
The finding puts wildlife managers in a difficult spot, Lamb said.
“Shooting wolves to save another species is an incredibly difficult decision.”
In 2020 and 2021, Alberta will cull 824 wolves.
Some caribou ranges are protected. In BC, an agreement between the province and a First Nation has protected 8,000 square kilometers – an area larger than Banff National Park.
Alberta has protected some habitat, but undisturbed habitat continues to shrink under pressure from the forestry and energy industry.
A recent study found that human disturbance increased in 23 out of 28 Alberta caribou subranges between 2018 and 2021. Development permits were approved for 700 square kilometers of caribou range.
Until those trends reverse, heavy-handed tactics like wolf culls will be the price of caribou herds, Lamb said.
“Every year we delay getting trees to grow, that’s another year of having to implement these interventions. I think we’re talking about many years of supporting caribou.”
This report was first published by The Canadian Press on April 23, 2024.
