'Thousands' of fish found dead in Ausable River near Port Franks, Ont.

The overwhelming numbers of dead fish that Jennifer Powell encountered as she paddled up the Ausable River this week absolutely shocked her.

“Anytime we passed any debris in the water, there were dead fish rafted up in the area. There was one pile that had a hundred dead fish in one pile. So, we’re talking thousands of dead fish,” said Powell.

Powell, a University of Toronto environmental sciences PhD student, is in Lambton Shores studying endangered fish species near Port Franks. She’s become the point person on a massive fish kill, stretching several kilometres up the Ausable River to the shores of Lake Huron, centred in Port Franks.

“As someone who has been trying to conserve fish, doing our best to save one or two species at a time, then to see thousands dead in one day. It’s heartbreaking,” she said.

The Ministry of the Environment, along with the Ausable Bayfield Conservation Authority, are now investigating the fish die off that was discovered a week ago.

A map created by PhD students who have been documenting the massive fish kill in the Ausable River near Port Franks, Ont. in July and August of 2023. (Source: Lambton Shores Endangered Fish Adventure)

No cause has been determined yet, and Powell said everything from water temperature to run-off could be to blame.

“It’s not necessarily a point source effect, like someone dumping stuff in the river. It could just be a whole mesh of things all working together,” she said.

It doesn’t make the sight of so many dead fish any less concerning, she said, as her and her PhD colleagues try to continue their work to document and conserve the fish that are left in the waterways near Port Franks.

Dead fish found in the Ausable River near Port Franks, Ont. by PhD students document the massive fish kill on Aug. 2, 2023. (Source: Lambton Shores Endangered Fish Adventure)“The Ausable River Watershed has had really poor water quality for a long time. As the effects of climate change keep getting worse, this kind of stuff is going to keep happening unless we take action to improve conditions in the entire watershed. This isn’t just a one time thing,” she said.

To report dead fish or potential pollution discharge in the Ausable River or any waterway, people can call Ontario’s Spills Action Centre at 1-866-663-8477.

To follow the Lambton Shores Endangered Fish Adventure, which Powell is a part of, you can visit their Facebook page.