More opossums popping up on Montreal's South Shore

When Claude Thériault took out the recycling one day in March, he was surprised to find an unexpected visitor hanging out on his doorstep.

"When I opened the door, the opossum was right there on the deck," said Thériault, who lives in a suburban area of Saint-Jean-sur-Richelieu, Que. 

"I almost stepped on him!"

Didelphis virginiana, the marsupial commonly known as the North American or Virginia opossum — or simply, a possum — lives mostly in the United States, Mexico and Central America. Its northernmost habitat stretches into Quebec's Eastern Townships, southern Ontario and the Fraser Valley in British Columbia. 

But in recent years, opossums have frequently been spotted in the Montérégie region, on the South Shore of Montreal. 

Anecdotally, residents of municipalities such as Otterburn Park, Saint-Jean-sur-Richelieu, Varennes and the Saint-Hubert sector of Longueuil, as well as in the Kanien'kehá:ka (Mohawk) community of Kahnawake have all reported seeing them.

While the first opossum sightings in Quebec date back to 1976, the population has been expanding since 2000, according to the province's Ministry of Forests, Wildlife and Parks. 

The animal is considered "well-established" in the Montérégie, albeit in "low density," and they've even been seen around Mont-Saint-Hilaire, according to the ministry.

"People are often a bit scared when they see them for the first time because they're funny-looking," said Carole Lacasse, director of client services at Proanima, an animal shelter with contracts with many South Shore municipalities.

She said the shelter often gets calls about wild animals in people's yards, including opossums. 

"They look like a big rat. But they're totally different than the rat as an animal," she said. "And they have moustaches … they're actually ugly and cute at the same time." 

Lacasse says opossums aren't often seen near the shores of the St. Lawrence River. "But as you go south, we start to see them," she said.

Some opossums have even been seen north of the St. Lawrence river, as far as Trois-Rivières in 2017, Boisbriand in 2020 and in Barkmere, in the Laurentians last year.

The ministry keeps track of reports of dead or injured animals but says, since it's not mandatory for citizens to report live opossum sightings, the government has only a partial portrait of the evolution of the population.