Blue-green algae is now in the Ontario waters of Lake Superior.
Blue-green algae is of particular concern because it can release toxins harmful to both humans and animals. It thrives in shallow, slow-moving warm water and can kill fish. While blue-green algae blooms are common in Lake Erie, it has never been confirmed before in Lake Superior.
Ministry of the Environment, Conservation and Parks spokesperson Lindsay Davidson said there were two unconfirmed reports of blue-green algae in Lake Superior in 2020 and five so far in 2021. Samples from the lake’s Black Bay were confirmed as blue-green algae in laboratory testing.
Ontario has an action plan to deal with blue-green algae blooms that includes reducing nutrient input into the Great Lakes, public awareness, and administering legislation, policy, and regulations to address water quality.