River otter spotted in the Detroit River for the first time in over 100 years signals hope

River otters have made a return to the Detroit River after becoming locally extinct in the Detroit River since the early 1900s.

“This return of river otters can give hope,” says John Hartig, visiting scholar at Great Lakes Institute for Environmental Research (GLIER).

“River otters like clean water. This is a statement the Detroit River is cleaner.”

On the morning of April 25, University of Windsor biology PhD student Eric Ste-Marie went for a walk along the Detroit River.

He noticed a furry brown creature pop its head out from under the water. A lover of nature, Ste-Marie pulled out his phone to capture the animal he had never seen before in the Detroit River.

“I assumed it was a mink or a muskrat which is more common in this area. But I noticed it was too large to be either of those,” Ste-Marie recalls.

After following the animal along the riverfront, Ste-Marie got a closer look. It was clear that it was a river otter.

“It was the last thing I was expecting to see,” he says.

Ste-Marie’s video is the first photographic proof of a river otter in the Detroit River in over 100 years.

“(This is) good news for you and me. If the Detroit River is clean for river otters, it’s cleaner for us as well,” says Hartig.

River otters were common in the area hundreds of years ago during the fur trades. They were over-harvested which caused the species to be extirpated from the Detroit River in the early 1900s.

Hartig also notes between the 1940s and 70s, the Detroit River was known as one of the most polluted rivers in the United States due to oil spills.

“Oil would matte their fur and they couldn’t thermal regulate. They couldn’t keep warm, they would die, so they couldn’t have survived during those years,” Hartig says.

In the 1980s, river otters were reintroduced to high-quality streams in eastern Ohio. Over the decades, the mammals travelled and expanded their habitat to parts of western Ohio.

They were spotted for the first time at Point Pelee National Park in 2019.

River otters are considered an indicator species of health fresh ecosystems.

“This gives us all hope that we all can make a difference in better caring for the place we call home,” says Hartig.