MDHHS: Tips to identify, avoid harmful algal blooms 

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The Michigan Department of Health and Human Services today issued a release urging residents to keep an eye out for the harmful algal blooms that can form on lakes, rivers and ponds. Since many DNR subscribers will be outdoors with family and friends this summer, we are sharing the update to keep you informed.

Stay safe this summer: Tips for identifying and avoiding harmful algal blooms 

If you or your family live near or will be visiting Michigan waters this summer, it's important to be aware of the potential for harmful algal blooms. HABs form due to rapid growth of cyanobacteria, also known as blue-green algae. Cyanobacteria are naturally present in lakes, rivers and ponds; unfortunately, some cyanobacteria produce toxins, called cyanotoxins, that can be present in blooms at levels that are harmful to people and animals.

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The occurrence of cyanobacteria and their toxins isn't unusual in the summer and fall and has been confirmed in lakes across Michigan in previous years. During 2020, 61 harmful algal blooms in 35 Michigan counties were reported to the Department of Environment, Great Lakes, and Energy.

HABs look like water that has algal scums or mats, look like spilled paint or pea soup, or have colored streaks on the surface. Visit the HAB Picture Guide for examples of HABs and other algae and plants mistaken for these blooms.