What Is Blue Green Algae?

Blue-green algae, also known as cyanobacteria, are commonly found during the summer in ponds, lakes and rivers. A combination of warm temperatures, sunlight and nutrient rich waters can cause blue-green algae to bloom. Blue-green algae consists of extremely small organisms and often looks like green paint floating on the water.

Since blue-green algae can produce toxins, it is dangerous for humans, animals or pets to drink the water or swim during a bloom. Signs of toxic algae may include dead fish or waterfowl, unexplained sickness or death of a pet, or skin rashes on humans.

Even though blue-green algae blooms are known to be very patchy in nature, avoid all contact with water containing this kind of algae. When in doubt, stay out!