On a brisk winter day in February 2019, then-provincial wildlife veterinarian Helen Schwantje and Chris Proctor, senior wildlife biologist with the province, travelled with a team of volunteers and a film crew into the remote valley of Ward Creek, a tributary of the Fraser River 60 kilometres north of Lillooet.
Grey clouds hung in the sky. A light dusting of snow skirted the mountain tops. In the monochromatic tan grasses of the valley bottom, the team huddled around a bighorn ram. Moments before, a sharpshooter in a helicopter had snared the animal in a net using a modified shotgun. The pilot landed. They quicky covered the sheep’s eyes to calm it, then attached the animal to a long line and slung it back to a field station. They worked methodically, taking blood, fecal and hair samples, and nasal swabs. After the sampling was done, they sedated the animal before using a PCR (polymerase chain reaction) kit to test the swabs for Mycoplasma ovipneumoniae (M.ovi), a deadly bacterium. Then they waited tensely for the results.
Domestic sheep and goats commonly carry the bacterium but have a natural resistance to it, minimizing symptoms to mostly weight loss. Among wild sheep however, M.ovi is a killer. It results in often fatal pneumonia that can wipe out 80 percent or more of a herd in a matter of months. Along with habitat loss, the bacterium is widely considered one of the gravest threats facing wild sheep, especially Rocky Mountain and California bighorns. Yet up until recently, few outside of the scientific and hunting community had ever heard of M.ovi.
Schwantje exudes a comfortable authority, someone who could just as easily hold her own in a locker room full of hockey jocks as she could in front of the lectern at an academic conference. But there wasn’t much chatter as the team went about its work. In fact, there was a solemn gravity to the proceedings that was palpable.
“We knew we were going to have to kill some animals,” Schwantje says.
Any sheep that tested positive was euthanized on the spot; it was a case of sacrificing the individual to protect the herd.
Wild sheep have roamed the mountains of North America for a long time. It’s believed they first colonized North America during the Pleistocene by crossing the Bering land bridge some 750,000 years ago. Large carnivores, that went extinct more than 10,000 years ago, like the short-faced bear, dire wolf and American cheetah, kept sheep numbers low. Afterward, they proliferated throughout the montane.
In Canada there are two species of mountain sheep, thinhorns and bighorns, each with two subspecies. Thinhorn sheep include Dall’s and Stone’s sheep and are found in northern BC, the Yukon and Northwest territories. Bighorns include an estimated 3,600 California bighorn that live in the arid ranges of south-central BC and the larger Rocky Mountain bighorn, which number roughly 3,000 in the Canadian Rockies. California and Rocky Mountain bighorns belong to meta-population of 18,000 animals in BC, Alberta and Montana. In BC they are blue-listed, which means they are considered at risk.
Scientists have known for almost a century that pneumonia was infecting wild sheep in North America and resulting in mass die-offs. However, it’s taken much longer to understand the bacterium and the mechanism of infection.
Schwantje, who grew up in Saanich in a family of six kids and had what she describes as a “free-spirited childhood,” has been one of the people leading the fight to find a fix for M.ovi. In fact, her graduate studies focused on M.ovi. Bighorn sheep have charisma, Schwantje says, and that made it relatively easy to get funding for her grad studies and research.
“A lot of people may never actually see bighorn sheep in the wild but they can’t imagine the mountains without them,” she says. “Back in the early 1980s the hypotheses around pneumoniae were evolving. For most bighorn pneumonia events, it was thought to be driven by a family of, at times, quite virulent respiratory bacteria,” Schwantje says, “no one considered Mycoplasmas (a genus of bacteria that lack a cell wall around their cell membrane), but it was impossible to test for them.”
If public support and funding for sheep conservation and research seemed relatively easy to come by, the key to mitigating the threat of M.ovi has proven much more difficult and complicated.
One fact was certain, protecting wild sheep from this disease would require building bridges with the farming community. Sheep farmers have lived with M.ovi-infected sheep for decades, many without even having even heard of the disease. Besides some stunted growth and a rare fatality in the flock, for the most part it was farming as usual. All good, except that wild sheep are naturally curious about their domestic kin, especially during the fall rut when frisky rams have been known to mingle and even mate with free ranging domestic ewes. One sneeze from a M.ovi carrying livestock is enough to infect one wild sheep and endanger an entire herd. The challenge was getting the message out to farmers in a way that didn’t sound like it was going to adds costs and hassles to their operation.
In 1999, M.ovi-caused a mass bighorn sheep die-off at Vaseux Lake, an important ecological hotspot north of Oliver in the heavily agriculturalized Okanagan Valley. Four years later, the disease decimated 80 percent of the 100-strong Chasm Creek herd, north of Clinton on Highway 97. These events galvanized wild sheep advocates and led to the formation of the Sheep Separation Program. The non-profit’s name said it all—at first, the goal was to reach out to sheep farmers located in high-risk areas where contact with wild sheep was an issue and help fund fencing to keep domestic flock contained, especially during fall rut season. It sounded good on paper, but there were problems with this strategy, says Jeremy Ayotte, who manages the program. Fencing is expensive, and some farmers gladly accepted the free fencing, but then either moved on to another type of farming or got out of farming altogether.
“Sheep are highly valued wildlife. It’s not hard to get funding,” Ayotte says, echoing Helen Schwantje’s words, “But the fencing program wasn’t working out. It was a waste of philanthropic money.”
It’s the reason the program has recalibrated to focus more on farmer education and facilitating more M.ovi testing of domestic sheep.
“Through this effort, we are building up our understanding of the prevalence of M.ovi on BC farms and helping to develop what may one day be part of provincial policy for testing of domestic sheep in high-risk areas,” Ayotte says.
Two years ago, a loose alliance of government biologists, the Wild Sheep Society of BC, as well as sheep and goat farmers, sent a letter to the provincial government asking for more regulation and testing of farms to stop the spread of M.ovi.
Last June, the Okanagan Nation Alliance lent its voice to the issue and formally requested that the province implement “legislation that will provide for effective means of separation between wild and domestic sheep and goats to ensure healthy wild sheep populations and the sustainability of sustenance, societal and ceremonial opportunities wild sheep provide, for generations to come.”
So far, there’s been no action on the legislation front. In an emailed response, a spokesperson for the Ministry of Agriculture and Food Security said that the “BC government continues to work with wildlife and farming partners on ideas and measures that support the health of both wild and farmed sheep but is not planning on implementing geographic restrictions or mandatory testing for domestic sheep at this time.”
Stone’s Sheep cross the Alaska Highway in Muncho Lake Provincial Park, BC.When it comes to beating M.ovi, the hunter-supported and conservation- focused Wild Sheep Society has been a stalwart ally for government scientists like Helen Schwantje and Chris Proctor. The organization has been willing to put dollars and volunteer time behind research and testing field missions. In fact, it was founded in the 1990s in direct response to the decline of the Fraser River meta population of California bighorns, according to the society’s executive director Kyle Stelter.
The M.ovi testing and management program that began in Ward Creek in 2019 has morphed into a 10-year management project funded to the tune of $1.5 million by Wild Sheep Society members, the Abbotsford Fish and Game Club, and other donors. It’s not just Canadians getting behind the project. American conservationists have a keen interest in BC, given that during the 1990s wild sheep from the Fraser River region were translocated to help reintroduce and shore up nearly extirpated populations in Nevada, North Dakota, Utah and Washington (Stelter estimates the Montana-based Wild Sheep Foundation has donated $5 million to BC conservation efforts over the past three decades.)
Besides testing and culling sick animals, the Wild Sheep Society has two other prongs in its three-pronged bighorn conservation strategy—good old public awareness and advocacy amongst domestic sheep producers, and diligently pushing on the public policy front. Stelter says the best-case scenario would see BC following the lead of the Yukon government that has regulated farm exclusion zones where there is high probability of interaction between wild and domestic herds. But it’s not the case of apples and apples. Yukon is sparely populated and has very few sheep producers. It’s a different story in BC. Stelter admits discussions with the government are slow going, especially with an agriculture ministry that has to balance the pressures of supporting farmers and food security with a conservation challenge like M.ovi.
“We’ve been talking about this for decades. We’re not against sheep farming and we believe there’s room for both on the landscape, but we have good conversations with government, and then it goes nowhere,” he says.
A big challenge is identifying where all the domestic sheep are in BC; and they’re not all found on commercial farms. According to Statistics Canada, the province is home to approximately 59,000 domestic sheep and 14,000 goats, which also can carry M.ovi. People raise them for all kinds of reasons, including meat, fibre and milk production, and for lawn and weed control. Others keep them as pets and or to train sheepherding dogs.
“Some people have a couple of sheep as pets, or to keep their grass under control. You can’t just go onto someone’s private property and tell them what to do or that we’re going to have to shoot their pet” he says, bluntly, “but all it takes is one sheep to get infected with M.ovi and it can wipe out a herd.”
The big fear is that this disease could spread to thinhorn sheep, BC’s other endemic mountain sheep species. So far thinhorns have been largely spared the ravages of M.ovi, but it’s more a function of luck and the fact that they occupy a much less densely human-populated habitat.
In the absence of a comprehensive management plan for sheep farms, having a M.ovi battling ally on the inside has proven to be a big ace in the hole. On a fall day, Jenn Bowes is sheering sheep at Riverside Farm in the Columbia Valley. In 2019, Bowes and her partner Trevor Hem pulled up stakes near Dawson Creek, where Bowes said their farm had become “surrounded by gas wells.” They trucked their flock south to a new property near Brisco in the Columbia Valley. It was an expensive move, but worth it. Being ecologically minded, Bowes called the Environmental Farm Planner in the Kootenays to introduce themselves — that’s when she learned about M.ovi. She had never heard of the disease, but she knew of a resident herd of wild sheep in Radium Hot Springs just south of her farm. At the urging of the farm planner, her next call was to the Wild Sheep Society of BC, which led her to Schwantje and Ayotte of the Sheep Separation Program. A few months later, Schwantje showed up at Riverside Farm in a pickup truck loaded with testing equipment.
“Things kind of snowballed from there,” Bowes says.
In the fall of 2019, 15 out of a flock of 75 domestic sheep at Riverside Farm tested positive for M.ovi. Bowes has managed to bring down the rate of infection and raise an overall healthier flock. To do so they used a mix of tactics culling particularly sick animals, separating infected animals from healthy ones and trying another tact with Schwantje—treating them with antibiotics.
Bowes was convinced that it was the right thing to do as a farmer. Not long after, she dreamed up an ingenious way to help fellow sheep farmers deal with unmerchantable wool while incentivizing them to take part in “free and confidential” M.ovi testing.
Wool can be shredded and compressed into a pellet, then used as an organic fertilizer and nitrogen fixer. So, Bowes bought a pelletizer and started offering to pay farmers 50 cents per pound for otherwise waste wool if they agreed to have their sheep tested. What started with 25 farms quickly gathered momentum.
“It’s exceeded my expectations. I thought I’d get a lot more resistance and I never thought that I’d be working on conservation as much as I am,” Bowes says.
Her pioneering efforts have led to new opportunities to expand the value-added wool incentive for M.ovi testing. A grant from The Columbia Valley Local Conservation Fund will support continued testing and monitoring of domestic sheep at farms between Spillimacheen and Canal Flats. At the same time, the Habitat Conservation Trust Foundation funded efforts to expand the program elsewhere in the province, in particular Peace River country that Bowes says is a hub of sheep farming, transport and wool collection.
Though domestic sheep have natural resistance to M.ovi, they’re not entirely immune. Bowes knows from personal experience. In her first year of M.ovi testing, her barn was full off coughing sheep and the wool quality suffered.
“There’s much less sneezing in the barn, the animals are healthier, and the wool quality is higher. I would never wish M.ovi on any producer. It’s a tedious journey to go through to try and get rid of it,” she admits.
But she says it’s worth it.
“I grew up in Edmonton and remember seeing wild sheep when we were driving to Jasper. I’m like a lot of people who can’t imagine the mountains without them.”
It’s a familiar sentiment. As a conservation issue, M.ovi is gaining momentum thanks to dedicated volunteers and government biologists. The award-winning conservation film, Transmission, is helping as well. Produced by BC-based Filter Studios, the film is a moving, inside look at M.ovi. It was released in early 2022 to wide acclaim, including official selection at the 2022 Banff Mountain Film Festival, and earning Best Environmental Film at the Echo Mountain Film Festival in Macedonia, among other accolades.
There’s some good news from a conservation biology standpoint as well. Up in the rugged highlands of the Fraser River in southwestern BC, California bighorns are doing better. The tough love of the testing and culling program has netted positive results. Provincial government biologist Chris Proctor recently completed a survey of the herd and found survival rates have gone through the roof. For at least two years prior to their first treatment in 2019, the Ward Creek herd had a zero percent lamb survival rate. That’s a death sentence for any sub-population of mammals. Today, lamb survival is more than 50 percent and that’s huge in terms of herd viability. Despite the good news, Proctor doesn’t see it as a long-term solution.
“Testing wild sheep is time consuming and expensive,” he says from his office in Kamloops. “The only real long-term solution is to keep sheep farms away from known wild sheep habitat. It wouldn’t be that hard. Wild sheep don’t live everywhere in the province.”
That’s why, for now, the solution to M.ovi remains an elusive though far from impossible conservation goal. Wild sheep are to the mountains of Western Canada what Orcas are to the Pacific Northwest Coast—iconic to the point that it’s hard to imagine the ecosystem without them.
