Explained | US faces threat from invasive Canadian ‘super pigs’: All you need to know

According to the United States Geological Survey (USGS), there are more than 6,500 non-indigenous species in the countryand one more has joined the list, “super pigs” from their neighbouring country Canada. Otherwise known as wild pigs, this invasive species had already been wreaking havoc in the North American region by eating crops, spreading diseases and even killing deers.

What are these so-called "super pigs"?

According to a report by the Guardian, these super pigsare a result of cross-breeding domestic pigs with wild boars and are said to be “incredibly intelligent, highly elusive” creatures. The crossbreed was created in Canada to help pigs withstand the country’s subzero temperatures.

In an interview with Field and Stream, Dr Ryan Brook, who leads the University of Saskatchewan’s Canadian Wild Pig Research Project, said this hybridisation in the 1980s resulted in bigger super pigs.

He added, the animals with larger bodies “survive the cold better and have better reproduction in those conditions.” According to Brook, in the 2000s after the market for farmed boars dropped many escaped their enclosures and now roam approximately 620,000 square miles in Canada.

They are “easily the worst invasive large mammal on the planet”, said Brook to the Guardian, in a separate interview. He added, “They’re incredibly intelligent. They’re highly elusive, and also when there’s any pressure on them, especially if people start hunting them, they become almost completely nocturnal”.

It was not until recently their population exploded in part due to their extraordinarily high reproductive rate. One of the pigs they found was said to weigh more than 300 kg, as per Brook. At the time, when these super pigs escaped their enclosures, experts thought they would not survive the Canadian winter and eventually freeze to death.

Got pigs? This is from SW Manitoba from a few days ago. Invasive wild pigs are doing extremely well with the relatively mild winter we've had so far. Some people are seeing fewer because the pigs aren't coming to feed and bait like they normally do when its -35C!. @agbiousask pic.twitter.com/emtcqBnb0c

However, the cold was not a problem for them as they survived it by tunnelling the snow and using “their razor-sharp tusks” to cut down a plant called cattails and line the bottom of this cave as a “nice warm insulating layer,” said Brook to the Guardian.

The US has a swine problem

These super pigs that are poised to enterthe US come at a time when the country is already dealing with a swine invasion of its own. This has cost the country close to $1.5 billion in damages with around six million of them in the US, as per government estimates, reported by the Guardian.

“The US has a 400-plus year history with invasive wild pigs, but we didn’t have any here until the early 1980s,” Brook told Field and Stream. According to the report, so far, the invasive species has largely proliferated in states like California and Texas but they have since started thriving in Canada and may soon spread to northern states like North Dakota, Montana, Michigan, and Minnesota.

“We see direct competition for our native species for food,” said Michael Marlow, the US Department of Agriculture official to the Guardian. He added that these pigs are “accomplished predators” with the male of the species having long tusks capable of hunting young fawns, turkeys and potentially quail.

Until a few decades ago, the pig’s existence was not an issue, said Marlow, but soon officials began noting an explosion in their population. He attributed this to the illegal smuggling of pigs by hunters who were “drugged and moved around, not always legally, and dropped in areas to allow the populations to develop”.

Meanwhile, Brook told Field and Stream there is a high chance the pigs have already entered the US. “We have documented pig occurrences less than 10 miles from the US border. Quite honestly, I think there have already been some in Manitoba going into North Dakota for the last five or six years”, said the Canadian researcher. He added, there is a “real risk of pigs moving south into the US”.

Why is this concerning?

These super pigs “feed on anything. They gobble up tons and tons of goslings and ducklings in the spring. They can take down a whitetail deer, even an adult,” said Brook, as per Field and Stream. Furthermore, they create a lot of environmental damage like eating crops grown by farmers, destroying trees, and even polluting water.

Pigs are also said to be capable carriers of viruses such as flu, which are transmittable to humans. Similarly, Marlow said that these pose “a human health and safety risk”. There is also a risk of a potential impact of a pig-borne disease like African swine fever. In 2018 and 2019, the disease reportedly killed more than 30 per cent of the 400 million pigs in China.

Mitigating the issue

Marlow, who is also assistant program manager for the US agriculture department’s National Feral Swine Damage Management Program said, his team has managed to eradicate pigs in seven states over the past decade, as per the Guardian. However, there is little hope to get rid of the swine completely, he added.

Echoing a similar sentiment, Brook told Field and Stream that there are no definitive population estimates and it is too late to get rid of these super pigs in Canada. However, they are working to mitigate the issue and one of the most effective control strategies was ground-trapping sounders (a herd of wild swine). His team uses what he called the “Judas pig” method where one pig is captured and fitted with a GPS collar and released into the wild in hope that it would lead them to a sounder.

“The idea is that you go and find that collared animal, remove any pigs that are with it, and in ideal world then let it go again and it will just continue to find more and more pigs,” said Brook to the Guardian. Brook also said that hunting them is not effective so the most important thing people can do is to alert authorities, reported Field and Stream.

(With inputs from agencies)