Slow start for blue-green algae on Alberta lakes

There have been fewer health advisories than usual about blue-green algae in Alberta lakes this past summer but that doesn't mean the problem is going away, explained a University of Alberta biologist.

"It has a lot to do with the odd spring we've had this year. March was warm, but a chilly April and May meant there was still ice on many lakes in the beginning of May," said Rolf Vinebrooke. "This delayed growing season means that lakes that typically see algal problems happening in June are only now seeing the beginning of blue-green algal blooms."

Long story short? If you're planning a trip to the lake, go sooner rather than later.

Blue-green algae blooms can have consequences beyond less-than-ideal swimming conditions. They also produce liver and neurological toxins that can affect humans, pets and other animals. And long-term, blooms can result in biological dead zones as algae eventually decay, depleting oxygen in lakes to critically low levels.

Different every year

Vinebrooke said we may see a rebound in algae populations—especially if the late summer and fall are warm, dry and calm.

"There are hints with some of the samples that we're receiving from Alberta Health Services that blue-green algae may be starting to make their appearance," he noted.

"But if the weather remains cool and rainy, we may see fewer blooms this year. Blue-green algae love warm temperatures, sun and concentrated nutrients. Rain tends to dilute nutrients and cloudy skies cool temperatures."