After 30 years in decline, Yukon's Finlayson caribou herd may be on the upswing, gov't says

After decades in decline, Yukon's Finlayson caribou herd population appears to be "stabilizing or increasing," according to recent population survey data from the territorial government.

The herd in southeastern Yukon is now estimated to be 3,359 animals. That represents a 24 per cent increase from the last estimate of 2,712 animals in 2017, and marks the first time since 1990 that the population has not shown a decline since the previous survey.

The Finlayson herd is part of a larger population of woodland caribou that are currently listed as a species of special concern under the federal Species at Risk Act. The herd's winter range lies north of the Pelly Mountains and east of Ross River, Yukon, and both north and south of the Robert Campbell Highway.

The most recent population survey was done over a few days late last winter, using helicopters to fly over the herd's range and count animals in different survey blocks. The population estimate has a 95 per cent confidence interval, meaning the actual population is somewhere between 3,085 and 3,634 animals. 

Even though the estimate is 3,359 animals, the government report suggests that may in fact be a slight overestimate, based on the survey method. 

"As such, a precautionary approach would be to consider that the real population size is likely closer to the lower 95  per cent confidence interval of 3,085 animals," reads a report on the recent survey data, released by the Yukon government last month.

"Nonetheless, the survey results are directly comparable to all past population estimates of the herd and are indicative of herd growth."

Population grew in the '80s before steady decline

The Finlayson herd has seen fewer ups than downs in the last half-century. Starting in the 1970s, the population was thought to be in decline because of over-predation by wolves, and also hunting pressure. The population at that time was estimated at about 2,000 animals but no formal counts were done until the 1980s.

Beginning in 1983, the government began a program to decrease predation on the caribou by culling the wolf population in the Finlayson herd's range. Over six years, wolf numbers were reduced by about 85 per cent.

The Finlayson herd, meanwhile, grew to about 6,000 animals by 1990.

Once the wolf control program ended, wolf numbers rebounded while the Finlayson caribou herd seemed to go into steady decline over the following decades. By 1996, the herd was estimated at about 4,500 animals and in 2007, to just over 3,000 animals.

"The population peak in 1990 and the subsequent observed decrease in herd size is difficult to evaluate demographically due to the manipulation of the wolf population in the area from 1984–1989," the report states.

The newest population survey is meant to "better inform decision-making related to the herd," specifically with respect to resource development in the region, the report says.

"With development projects such as the Kudz Ze Kayah mine proposed to occur within the herd's range and ongoing interest in mineral exploration, there are concerns about cumulative effects and the long-term persistence of Finlayson caribou," it says.

A contentious development

Vancouver-based BMC Minerals, the company behind the Kudz Ze Kayah mine project, wants to extract 1.8 million tonnes of zinc, 350,000 tonnes of lead and 600,000 tonnes of copper deposits over 10 years at the proposed site, about 115 kilometres southeast of Ross River, Yukon. At peak production, the mine will be capable of housing 250 workers.

The mine project is contentious; last year a legal action was brought forward by the Ross River Dena Council on behalf of the Kaska Nation, which is composed of five Dene-speaking First Nations in Yukon and B.C. The First Nations want a judicial review of the federal and territorial government decisions to sign off on an environmental assessment of the Kudz Ze Kayah project. Last month the government filed its response to the court, saying that the First Nations had been adequately consulted.

Speaking this week to CBC News, Ross River Dena Council Chief Dylan Loblaw said his community is very concerned about the Finlayson herd, and he's sceptical about the latest government survey data.  

"The relationship that our nation has with the caribou is pretty important. It's critical to our survival. You know, we relied on caribou since time immemorial and beyond that," he said.

"The [population] numbers aren't increasing as much as we'd like to see, from our observations."

Loblaw questions the accuracy of the government's survey method. He says the results don't agree with what his community has seen with the Finlayson herd in recent years.

"They're using helicopters and planes to map out each square kilometre on the caribou's route which isn't quite 
accurate, and it also disturbs the caribou because the herds are quite sensitive to noise," he said.

"We've talked about it before, and we'd let our counterparts know how we feel about the western science approach."

Mining company welcomes results

BMC Minerals, meantime, is heralding the latest population estimate as good news. Company representatives were involved in the survey, riding along in the helicopters last winter.  

"We're pleased to see that the Finlayson herd appears to have stabilized and appears to have started to increase. We think that's very good news," said Allan Nixon, vice president of external affairs with BMC Minerals.

Nixon is also confident that the company's plan for the Kudz Ze Kayah project will minimize any impact on the Finlayson herd.   

"We do have an adaptive management plan. We do have this Finlayson caribou herd oversight committee now which didn't exist before, and which will provide that guidance and make sure that, you know, BMC is living up to its obligations," he said.

"Anything could have an impact [on the herd], so whether it will or not is dependent on the mitigation and the efforts of the parties."