By the time Greg Gilbertson became a provincial fish and wildlife officer for the Alberta counties of Woodlands and Lac Ste. Anne in 1998, calls for help in dealing with wild boar were part of the job. Ever since Eurasian boar farms were approved in Alberta in the early 1980s, the wily swine had been making a break for it, knocking down fences, tunnelling beneath them or simply finding openings made by outsiders hell-bent on establishing a wild pig population to hunt. Free to breed like mad and roam the surrounding area, travelling bands of boar, called “sounders,” had begun busting into feed stores and plundering crops. Their rooting behaviour was particularly concerning. “I saw extensive damage to patches of pasture,” says Gilbertson. “Recovery of the vegetation would have taken a very long time.”
Wild boar populations have now expanded well beyond the counties Gilbertson worked in. Alberta officials receive reports “all the way from north of Peace River to Vermilion and all points in between,” says Perry Abramenko, an inspector at Alberta Agriculture and Rural Development and the lead on wild boar management for the province. Boars have spread across all counties between Grande Prairie and Lesser Slave River, and have been sighted in watersheds abutting Banff and Jasper national parks. They have been found in most counties between Edmonton and Calgary, and several counties near the Saskatchewan boundary, including the Cypress area, where some find refuge in coulees. While their exact numbers aren’t known, the range of wild boar has grown exponentially over the past three decades, due in part to a sow’s year-round, rapid-fire reproduction rate of up to 12 piglets (two litters of six) per year. This perpetual population explosion brings with it an ever-increasing risk that wild boar will harbour a multitude of diseases, in addition to wreaking havoc on sensitive ecosystems, species at risk and entire forest communities. It’s why, under Alberta law, wild boar outside the confines of farms are designated as “pests,” says Abramenko. “It’s the same designation we give Norway rats.”
The Government of Alberta aims to eradicate wild boar and is currently piloting a program to that end. If the effort doesn’t succeed, Alberta may suffer the same ecological destruction and economic fate as many countries across the globe.
Few people know the high stakes associated with a wild boar population better than Dale Nolte. Based in Fort Collins, Colorado, Nolte is the manager of the national feral swine damage management program as part of the United States Animal and Plant Health Inspection Service. Through his program, Nolte manages everything from public education about wild boar to operational removals of large sounders. He estimates at least six million feral swine live in the US, mostly in the southern states (e.g., Texas and Florida) and California.
“Feral swine tear up habitats,” he says. They are the worst kind of ecosystem engineers—rooting, wallowing and trampling their way through forests and marshes. They contaminate soil and water, mow down native vegetation and make way for invasive plants. In the US their presence has been linked to the decline of nearly 300 native plants and animals—250 of which are species at risk. And they are doing it in multiple habitats. Before they were removed from Keewaydin Island in Florida, wild boar in some years dug up and ate every single one of the eggs laid by endangered green sea turtles. Farther north, in prairie states, they continue to eat the eggs and chicks of ground-nesting lesser prairie chickens. They’ve trashed the delicate wetland habitat of the Hine’s emerald dragonfly and trampled the tallgrass prairie and glade habitat that Mead’s milkweed depends on. “The are having a tremendous impact on efforts to recover endangered species,” says Nolte.
Free to breed like mad and roam their surroundings, bands of boar bust into feed stores and plunder crops.
It’s no different in Alberta. The swine have already begun to wreak havoc on sensitive prairie ecosystems, says wild boar researcher Ryan Brook at the University of Saskatchewan. “They love wetlands—the vegetation, eggs, nesting waterfowl, goslings, ducklings, frogs and salamanders. Everything wetland is right down the hatch.”
That’s a concern in the “Prairie Pothole” region—a series of wetlands across western and southern Alberta “that are important breeding areas for waterfowl,” says Ruth Aschim, a doctoral student with Brook who did some of her research on the local wild boar population. The pothole region is home to 600 species of plants and animals, more than 50 of which are at risk, and some of the wetlands are located in current Alberta boar habitat—what Aschim calls the fringe between aspen forest and agriculture, especially in the counties of Barrhead and Lac Ste. Anne. Here the boar have the protection of the forest but can emerge to hit up wetlands and crops, often under the cover of darkness.
Crop damage and other agriculture losses from wild boar are significant. Abramenko says a producer in Lac Ste. Anne County had to reseed a third of his oat crop because of wild boar damage. And while claims have just begun to come in across Canada, Nolte says agricultural losses to wild boar cost the US at least $1-billion in damages every year. Exact numbers are hard to calculate because of the many ways wild boar can cause damage and affect profit. Nolte points to a case where, over a 90-day period, wild boar inhaled $1,250 worth of one Texas producer’s cattle feed. “You don’t want to lose that [money], but a big feedlot can withstand it,” says Nolte. But further investigation revealed the losses were much higher. Not only were the pigs eating the cattle’s feed, but they were harassing the cattle and aggressively blocking their access to the feeders. The producer had kept careful records of cattle weight gain before and after the boar raids began. Before the boar, cattle were gaining an average of two pounds per day, but in the presence of boar, only one pound daily. In the end, the producer lost an estimated $27,000 in pounds of beef over the 90 days. Abramenko suspects livestock harassment is happening in Alberta as well—but because many boar are active only at night, farmers may not know about it.
In addition to agricultural losses, wild boar cost the US another $1-billion in damages across numerous other sectors. They destroy infrastructure, including levees for flood control, says Nolte. Claims have come in for landscaping around homes, parks and golf courses. There are costs associated with the protection and recovery of wildlife. Insurance agencies are estimated to annually pay out US$36-million in property damage and personal injury claims related to wild boar.
Another massive cost could come from the spread of diseases and parasites to domestic pigs. Though boar are hairy and have longer snouts, they are essentially the same species, in the way huskies are the same species as poodles. Diseases and parasites can move easily between them. Fences have done little to prevent wild boar from getting into domestic pig pens, says Brook, who’s snapped photos of them doing just that in Saskatchewan. Andrew Heck of the Alberta Pork Council says one of their biggest concerns is the potential for wild boar to spread African swine fever (ASF), a highly contagious virus that causes high fevers, damages the vascular system and kills large numbers of infected animals. There is no cure. The World Organisation for Animal Health is sounding alarm bells as ASF spreads seemingly unimpeded through Russia, the Caucasus and now China. It has not yet been detected in Canada or the US, but is a reportable disease in both.
The Pork Council is also concerned about porcine epidemic diarrhea (PED), another viral disease of pigs that causes watery stools and vomiting. It sometimes kills piglets. Though it’s been in Canada since 2014, PED showed up in Alberta for the first time this year—there have been four documented cases since March 18, though one was later deemed a “false positive.” “Wild boar could spread it if they were to come in contact with the disease anywhere in the province and then move it from one site to another,” says Heck.
While a PED outbreak would potentially be costly, most pork farmers could recover, Heck says. “But ASF would devastate the industry.”
Nolte too has his eye on ASF, as well as a number of other diseases that pose a threat to agriculture and also to hunters who handle wild boar. For example, US feral swine carry the bacteria that cause brucellosis, a reportable disease in North America, which can cause abortions in pigs and flu-like symptoms in humans. Brucellosis and other diseases of similar concern are well managed by the agriculture industry. In contrast, feral swine are free ranging and have unique opportunities for contact with people, wildlife, livestock and their habitats. As their populations continue to balloon, so do opportunities for infection.
For all of these reasons, The Alberta government is taking a number of actions to beat back wild boar populations. They’ve recently implemented minimum containment standards for boar farms. Owners are required to install either a single fence that is partially buried in the ground, or a double fence. Both need to be 1.5 metres high and include an electrified wire that packs a 4,000 volt punch. “Pigs have wet snouts. It’s quite effective,” says Abramenko, adding, “They’re smart enough to learn after the first shock.”
While working on minimizing escapes, the province is also piloting a number of projects to aid in eradication. They are learning from past endeavours. Early attempts to manage the population through a hunting bounty from 2003 to 2014—$50 per set of ears—did not appear to slow their spread, according to Brook’s and Aschim’s research. In fact, across the continent, hunting in general has done little to beat back boar populations, and often exacerbates the problem. “When people go out and shoot only one or two out of a sounder, then [the surviving boars] disperse into new territories, become nocturnal and become very wary of humans,” says Abramenko. “It makes it almost impossible to eradicate them.”
“You need to be doing what we call whole-sounder-removal,” says Brook. “You find 12 animals, you kill 12 animals.” Abramenko is on board and is currently testing a number of techniques to bait whole sounders into electrified traps. It’s not as easy as it seems—wild boar are incredibly smart, and wary of new structures and smells. It can take days for them to accept the traps and move freely in and out, particularly as a group. The traps are equipped with cameras that Abramenko can monitor from his phone, along with remotely controlled gates he can shut as soon as the whole sounder is inside. Once captured the boar are humanely euthanized and taken to post-mortem labs for necropsies and disease testing.
Abramenko is also testing the use of camera-equipped, remotely piloted aircraft (RPAs), or drones, to more easily track boar, especially in the winter. One of the RPAs has an infrared camera that can detect boar travelling through vegetation. Ultimately this will help the team find boar more quickly when a formal operational management program is established. Abramenko says this will happen in a year’s time, after one more year of piloting the program “to get more experience.”
One of the barriers to eradication will be to get wild boar hunters to support the effort. “They’re fun to hunt,” says Nolte. “I get why people want to do it.” Swine can also be quite tasty, adds Gilbertson. But there are downsides for hunters, too, especially if they also enjoy hunting other game. In the areas Gilbertson likes to hunt in Alberta that also have wild boar, he says, “there is no question a lot fewer white tail deer are using those areas.” Nolte has observed the same thing in the US, where he says feral swine have been “totally destructive” to other game species such as deer and wild poultry.
The Alberta Fish and Game Association, an organization that “advocates the common interests of ethical hunters,” says it will support any decision the government makes about wild boar.
Wild boar are essentially the same species as domestic pigs. Diseases and parasites can move easily between them.
Still, “there are people that don’t want erad-ication—they enjoy hunting boars too much,” says Abramenko. If the information he’s collected in the pilot program supports it, hunting restrictions may be part of the suite of actions he recommends next year for inclusion in a provincial wild boar management plan. For Brooks, the way forward is clear: “The reality is you can’t have a meaningful conversation about eradication if you have sport hunting.”
Regardless, the sooner a management program is formalized, the better, says Nolte. “The advice I would give is to put a plan together and start taking care of a problem in its infancy. Don’t wait until you have a major issue to address. I just can’t believe feral swine won’t do quite well in Alberta. Populations [will] continue to increase.”
Jasper-based Niki Wilson writes mainly on science. Comment on this story: firstname.lastname@example.org