Harmful Cyanobacterial Blooms (HCBs), also known as Harmful Algal Blooms (HABs), are dense concentrations of cyanobacteria, commonly referred to as blue-green algae, in waterbodies. Waterbodies contaminated with these algal blooms pose a health risk to people (illness) and animals (possible death) that have direct contact with contaminated water (swimming, drinking, breathing aerosols).

 

HCBs typically develop in mid to late summer and can occur in flowing and non-flowing waters such as steams, rivers, lakes, and reservoirs. HCBs may be green, tan, brown, or blue-green in color. HCBs may float in or on the water and look like spilled paint, grass clippings, clumps, or scums.  They may also be attached to aquatic plants, rocks, or other material and look like films, mats, or gelatinous balls.

You cannot tell if a cyanobacterial bloom is toxic by looking at it.  The best way to protect yourself, your family, and your pets is to be aware of HCBs in Wyoming waters and stay away from any water with signs of an HCB.  Do not let your animals drink, swim or eat near discolored or scummy water, and keep them from licking their fur, eating dead fish or animals found near an HCB, or eating HCB material. 

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The following are some resources on HCBs/HABs to keep yourself and your animals safe.

We have also included some pictures of a bloom below.

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