TOLEDO, Ohio (AP) — Algae blooms are back in western Lake Erie, this time a little earlier than normal.

Researchers say the higher temperatures this summer have brought out the sometimes-toxic algae about a week or two earlier.

The algae that turn the water a pea soup green color have been spotted along the shore east of Toledo, around the Lake Erie islands and along some beaches in Cleveland.

Researchers tell The Blade in Toledo that it’s not clear yet whether these blooms are the beginning of the main summertime bloom or early-season surprises.

Algae blooms can foul drinking water, sicken swimmers and harm aquatic life. They’ve become an annual problem in the lake and are a growing concern nationwide.