In their fenced-off enclosure, the lambs at Wheaton River Gardens lay in a beam of early-spring sunlight with their mothers. Only a few days old, their cottony fleece and shiny black eyes give them them the appearance of new stuffed toys. The bravest stands up on long, wobbly legs and wanders over to a hole in the fence, nibbles delicately on the tips of my fingers through the mesh.
Cute he certainly is, but according to Environment Yukon and the agriculture branch of the Department of Energy, Mines and Resources, he might also be deadly to thinhorn sheep. Officials worry about the possible transmission of pathogens between domestic sheep and goats and wild thinhorns, an issue which has caused some tension among local farmers.
Thinhorn sheep — of which the Yukon has the largest population in Canada — contain three species: Dall sheep, Stone sheep and Fannin sheep, which are hybrids between Stone and Dall sheep, said Jane Harms of the animal health unit of Environment Yukon. The concern comes from die-offs of bighorn sheep, to which the thinhorns are closely related. Bighorn sheep can contract pneumonia from domestic sheep via bacteria the animals carry, Harms said.
The domestic animals often don’t show symptoms, but when wild sheep contract the bacteria the infection is usually fatal, she said. Animals that do survive become chronically ill and susceptible to infections from similar respiratory diseases. They also pass along the disease to new lambs, weakening the entire population.
“Herds with these infections don’t tend to do well after the initial die-off,” Harms said, adding that the infections make population recovery and conservation difficult.
These die-offs — or the pathogens that cause them — have not been reported in Yukon thinhorn sheep, Harms said. There was a case of herd infection from domestic-wild interactions at the Toronto Zoo which resulted in the death of several animals. Harms said sampling of hunter-harvested thinhorn sheep, as well as testing of animals who died of unknown causes, have not shown any evidence that Yukon populations are currently contracting these infections.
A March 2016 risk assessment report by the Canadian Wildlife Health Cooperative on the possibility of transmission between domestic and thinhorn sheep for Environment Yukon said “the exact nature of the risk of pneumonia of thinhorn sheep acquired from domestic sheep cannot be determined for the Yukon … due to limits of available information,” but thinhorn sheep are “presumably” capable of infection.
“There’s certainly a risk and we consider the threat real,” said Harms.
Based on this risk assessment and the bighorn die-offs, the government is asking Yukon farmers to install double fences or electric fencing for their sheep and goats to keep domestic and wild sheep separate. But that process is expensive, labour-intensive and puts the onus on farmers, said Shiela Alexandrovich, who owns Wheaton River Gardens in Mount Lorne. Alexandrovich has six ewes, a ram and several lambs.
This issue has “slid down the pipe” to farmers, she said.
No work has been done to determine where the two populations might overlap and officials have not been out to her farm to see if interaction is possible, Alexandrovich said. The agricultural branch “has no idea where domestic sheep are” in the Yukon, she said.
“It’s an issue that’s been coming up since January,” Alexandrovich said. “Give me the numbers, come and see me and consult with me.”
David Murray, a manager with the agricultural branch, said there were no numbers available on how many domestic sheep and goats are in the Yukon, who owns them or where they are. He added it is difficult to test for the pathogens in sheep, so knowing when domestic animals are infected is challenging.
The expectation that farmers double their fencing means “wicked heavy labour and investment,” Alexandrovich said. Most farmers who have sheep and goats are not commercial farmers but homesteaders for whom the additional work and expense is a heavy burden.
“Homesteaders are the core of local food production in the Yukon,” she said.
Jesse Devost, a spokesperson for Energy Mines and Resources, said farmers can apply for funding to offset the costs through the federal Growing Forward 2 agricultural program.
Alexandrovich said she has never had a wild sheep on her farm. Thinhorn sheep, she said, live high in the mountains, nowhere near her animals.
“Wild sheep are pretty territorial,” she said. “They’re not exactly wandering nomads.”
A 2014 report on thinhorn sheep by Environment Yukon would appear to agree with her. It said thinhorns “use the same migration routes generation after generation” and return to the same grazing grounds each year.
Tom Rudge of Aurora Mountain Farms near Lake Labarge said he disputes the findings of the 2016 risk assessment.
“I wouldn’t say it was a good assessment,” he said. “It was a lot of anecdotal evidence and not a lot of science and … they draw a lot of big conclusions from it.”
“This has been blown out from one reported incident in Dawson … they took information from the south, overlaid it in the Yukon and didn’t do the appropriate groundwork for the population size,” said Alexandrovich. “I feel like there isn’t enough information being provided to me for me to take this seriously.”
One of the concerns highlighted in the risk assessment report is the potential impact die-offs would have on outfitters and wild sheep hunting.
The report said it could not determine the exact value of sheep hunting to the economy. Between 2006 and 2015, the sale of sheep hunting seals generated between $10,000 and $13,000 annually in the Yukon. This doesn’t include licenses, permitting costs or revenue from guiding activities.
“They’ve quantified (the risk) in a dollar value in the (risk assessment) in what having a large population of thinhorn sheep is worth,” said Rudge. “Mostly, it’s trophy hunting of sheep.”
Shaun Wasel, executive director of the Yukon Outfitters Association, said thinhorn sheep are important to Yukoners and outfitters alike as “a symbol of the great wild.”
“We feel it is best to be pre-emptive now to prevent infections,” he said.
Although the disease has only been reported in bighorns, Wasel said it was possible for it to “manifest the same effects” in thinhorns.
Rudge said he didn’t have anything against outfitters, who need to make a living.
“We need to protect the thinhorn population, but what do we use them for?” he said. “We use them for trophy hunting. You have kind of have to twist your head around to think about that.”
“What are we protecting all these thinhorn sheep for?” Alexandrovich said. “So we can shoot them in 10 years?”
“Conservation is a priority for us,” said Wasel.
Rudge said some concern about disease transmission is valid, but there has been poor communication between Environment Yukon, the agricultural branch and farmers.
“It’s a little bit worrisome that they keep throwing things on the table like this,” Rudge said. “We need to protect wild sheep and everyone has a role to play… but I think the communication got messed up.”
“There’s definitely a hard feeling (about this) among some farmers.”
Contact Lori Garrison at garrison.lori@yukon-news.com