Blue Green Algae
Blue-green algae, also known as cyanobacteria, are a group of photosynthetic bacteria that people sometimes refer to as "pond scum." Blue-green algae generally grow in lakes, ponds and slow-moving streams when the water is warm and enriched with nutrients like phosphorus or nitrogen.
When blue-green algae float to the water surface they form floating mats which is called a "blue-green algae bloom." In Wisconsin, blue-green algae blooms generally occur between mid-June and late September, although in rare instances, blooms have been observed in winter, even under the ice.
This fact sheet can help you tell blue-green algae apart from their non-harmful look-alikes.
Click here for up to date satellite images of cyanobacteria algal blooms in Green Bay and Lake Winnebago.
Here's how you can protect your family from Blue-Green Algae:
