Rare river otter spotted in Niagara wetland, pointing to species’ comeback in southwestern Ontario

Wildlife photographer Terry Chettle was taking pictures of a green heron at the Grimsby Wetlands in early August, when something surprised both him and the bird.

“All of a sudden this river otter started taunting the heron a bit,” the Beamsville, Ont., resident said. 

Chettle told CBC Hamilton he was surprised to see an otter, because they’re uncommon in the area. When it moved to a log and started pruning, he took its picture.

“It put on a show for me,” Chettle said Tuesday. “Kind of gave me the tongue out and the wave.”

That same day, Bruce and Laurie Mackenzie were out for a walk in the wetland. They met Chettle, who pointed out the otter. 

Bruce Mackenzie agreed it was a rare find, saying as far as he knows, that Aug. 3 sighting was the first near the wetlands in recent memory. He said he doesn’t know of anyone seeing the otter since that weekend.

The area — which used to be where Niagara Region stored sewage — is managed by the Hamilton Naturalists’ Club and covers about 12 hectares on Lake Ontario’s South Shore. Mackenzie works with the naturalists club, serving as project manager for the wetlands — now a popular hiking and bird-watching spot. 

The otter sighting “speaks well of habitat restoration and water quality,” he told CBC Hamilton, noting rare species have been spotted in the wetlands before, including least bitterns — small herons threatened in Ontario.

Otters a conservation ‘success story’

“We’re quite excited about different species showing up,” Mackenzie said. “They indicate that kind of life can be sustained because of the rewilding of the Golden Horseshoe.” 

Otters are a conservation authority success story, Laura Timms, a program manager in natural heritage management at Credit Valley Conservation, told CBC Hamilton.   

That conservation authority oversees the Credit River watershed, which includes much of Mississauga and Peel Region. In 2025, it published an article about river otters making a comeback in the area. 

The authority doesn’t track specific numbers, but Timms said there’s a clear upward trend. A decade ago, she said her team would have assumed reports of otters that didn’t come with photos were actually from people mistaking the slinky brown mammals for minks. 

Now, she said, documented sightings are more frequent, including at the Rattray Marsh and Jim Tovey Lakeview conservation areas this year, where some of the otters gave birth to pups.

CBC Hamilton asked the Hamilton and Niagara conservation authorities about their observations of otter populations. A spokesperson for the Niagara Peninsula Conservation Authority said it doesn’t monitor wildlife. The Hamilton Conservation Authority did not respond before publication. 

River otter numbers broadly declined in the 1800s due to hunting, poor water quality and the destruction of their habitats, Timms said. 

Now, she said, populations in North America are more broadly rebounding due to “decades of effort” to turn degraded environments into healthy ones, benefitting all species.

WATCH | How Ontario regulations for protected wetlands have changed:

The case of the disappearing wetlands — how new Ontario rules are affecting once-protected areas

In 2023, Ontario’s Ministry of Natural Resources updated its scorecard for provincially protected wetlands, effectively dropping 55 hectares from Ottawa’s rural west end in the process. The CBC’s Kate Porter looked into what that might mean for the future of wetland conservation.

More work needed to improve biodiversity

River otters can grow up to 1.4 metres long, and weigh five to 14 kilograms, Credit Valley Conservation said on its website. The carnivorous critters can build dens and live in rivers, lakes and creeks, where they hunt fish, clams, insects and other aquatic animals.  

“We love to talk about [otters],” Timms said, “but it’s important to remember that there’s a lot of biodiversity that is still facing lots of other challenges.”

For example, “we’ve lost most of our wetlands,” she said, noting those habitats support a wide variety of species, store carbon and prevent flooding. 

“We need to continue to work to restore and protect all our habitats so that all species can thrive and we can see more conservation success stories like otters.”