What is a cyanobacterial (blue-green algae) bloom and how does it form? – Blue-green algae are a group of organisms that can live in freshwater, salt-water or in mixed “brackish” water. Most of us know them as “pond scum.” They also have been found to share some characteristics with bacteria, which has led to them being referred to as “cyanobacteria.”
Within a few days of development, a bloom can cause clear water to become cloudy. Winds tend to push some floating blooms to the shore where they are very noticeable. Blooms can occur at any time, but most often occur in late summer or early fall.
What do cyanobacterial blooms look like? – Some cyanobacterial blooms can look like foam, scum, or mats on the surface of fresh water lakes and ponds. The blooms can be blue, bright green, brown, or red and may look like paint floating on the water. Some blooms may not affect the appearance of the water. As algae in a cyanobacterial bloom die, the water may smell bad.
Tips for avoiding cyanobacteria/blue-green algae: It is important that adults, children and pets avoid swimming in or drinking water containing blue-green algae. It is best not to come in to contact with water in areas where you see foam, scum, or mats of algae on the water.
Do not eat fish that are harvested from areas near or in blooms. Blue-green algae can sometimes affect the liver, nervous system and skin. Abdominal cramps, nausea, diarrhea, and vomiting may occur if the affected water is swallowed. Some people who are sensitive to the algae may develop a rash or respiratory irritation. If you come into contact with an algae bloom, wash with soap and water right away. If you experience an illness, please contact your healthcare provider immediately.
Contacts to report fish kills or illness associated with blue-green algae:
Fish Kill Hotline (Florida Fish & Wildlife Conservation Commission) 1-800-636-0511
Human Illness (Florida Poison Control Center) 1-800-222-1222
For additional information related to algae is available on the DOH website http://www.floridahealth.gov/healthy-environments/aquatic-toxins/index.html, the Centers for Disease Control and Prevention webpage- http://www.cdc.gov/nceh/hsb/hab/default.htm and this fact sheet- http://www.cdc.gov/hab/cyanobacteria/pdfs/facts.pdf.