Invasive wild boars that have been roaming the prairies for decades are now at risk of jumping the border.
“The risk around establishing new populations in northern U.S. states is very real,” said Saskatchewan agriculture and bioresources professor Ryan Brook.
“Montana has no wild pigs. They don’t want wild pigs. So one pregnant sow moving in there could change their situation dramatically.”
Brook, who has been researching wild boars for more than a decade, called the Canadian prairies a “wild pig factory.”
Wild boars, often known as super pigs, have a “supercharged” reproductive capacity. The animals can birth six pigs per litter and have multiple litters a year, according to Brook.
“This is the worst invasive large mammal on the planet,” he said.
“These things are everywhere except Antarctica. They’ve been hugely successful globally at spreading and being a problem.”
The boars have razor-sharp tusks and thick fur that helps them survive harsh Canadian winters. They can grow to be as big as 272 kilograms. They destroy crops and natural habitats, sewer water systems and spread disease.
“They can host up to 89 different diseases that can transfer to wildlife, humans and livestock. If something like that ever got into a wild population, it’d be really difficult to control,” said Paige Kuczmarksi, an invasive species technician with the Alberta Invasive Species Council.
Wild boar were first imported from Europe in the 1980s to help diversify Canada’s livestock population. The pork market collapsed in the early 2000s and forced many farmers to let the pigs roam free.
“In a sense, we did it to ourselves,” she said.
Core populations of the pigs live in Alberta, Saskatchewan and Manitoba. But wild boars have been found over an area larger than one million square kilometres across the country, according to Brook.
There have been reported sightings in Manitoba about 30 kilometres from the U.S. border. In Alberta and B.C., feral swine have been tracked even closer to neighbouring states.
“This is a very serious crisis,” Brook said.
Threat to the U.S.
Wild pigs have been reported in at least 35 states, according to the United States Department of Agriculture (USDA), which estimates the total swine population is about six million.
The USDA, along with other agencies, is in the process of developing a feral swine detection plan for Montana and North Dakota.
While some states are considered wild boar-free, Brook said it is only a matter of time before the mammals move in.
“There’s a good chance that some things have already made that move and just simply haven’t been detected,” he said.
The Invasive Feral Swine Transboundary Working Group has been set up to connect both Canadians and Americans working to manage and prevent the spread of wild pigs.
‘Squeal On Pigs‘ is an North American awareness program, incorporated by many members of the group, that encourages the public to report all signs and sightings of wild boars.
In Alberta, if reports are substantiated, officials will set up corral traps in the area to capture entire groups of pigs.
Alberta has had a reporting program in place since 2018. In that time, they’ve captured 380 boars, according to Kuczmarski. However, there are no real estimates to suggest how large the boar population is across the prairies.
“I would say there’s a significant amount of boar on the landscape compared to the 380 that we removed,” she said.
Controlling the species is difficult, according to Kuczmarski. Wild boars are often nocturnal and they avoid humans.
“Pigs are very smart in general. Now mixed with a wild species they are even more savvy,” she said.
Hunting feral swine has the reverse effect when it comes to pest management. The animals can remember the sound of any disturbance and change their behaviour to protect themselves.
“They’ll pass this onto their young and they’ll change dispersal patterns,” Kuczmarski said.
Alberta discourages hunting wild boars, but the practice is still legal year-round.
In Minnesota, a state working to keep feral swine away, law prohibits wild pig hunting.
“Opportunities to hunt pigs can incentivize introduction into Minnesota and can stymie efficient control and removal of feral pigs,” according to a recent report from the Minnesota Department of Natural Resources.
The report surveyed the public on the perceived risks of feral pigs invading the state. The majority of respondents, 91 per cent, were concerned most about the damage to habitat, followed by wild animals, farm animals and public health.
“Many indicated that they were concerned about increased erosion leading to habitat loss and destruction, resulting in negative impacts on native vegetation, biodiversity and ecosystem function and water quality,” the report stated.
The USDA estimates the annual cost of feral pig damage exceeds US$2.5 billion.
