Red tide is a phenomenon caused by algal blooms. Algal blooms are when concentrations of algae become so numerous they’ll discolor the coastal waters. These algal blooms will also deplete the oxygen levels in the water while releasing a toxin that will cause illness in wildlife.
The algal bloom is a result of excess nutrients, that cause a large growth of algae and green plants. As the amount of algae and green plants grown the other loose the balance and die off. When these algal blooms grow large enough to produce a toxin that will cause illness in wildlife they will also begin to effect humans. Small amounts of this toxin in the air will cause mild respiratory issues, itchy skin, and red eyes (if you rubbed your eyes or open them under water). The respiratory issues is most important concerning elderly and anyone with asthma.
Since Florida has experienced one of the wettest rain seasons in a few years, it is possible that multiple sources such as lawns and farmlands washout the chemicals and fertilizers used regularly and flow from local rivers into the ocean point of entries. With red tide taking hold for this long period more than fishing businesses have suffered. The large amount of dead wildlife on the beaches has deterred visitors and local beach goers from coming to these locations.
As of October 1, 2018, the report from the Florida fish and Wildlife Commission shows a general decrease in the red tide concentrations and fewer reports off the coast line into the Gulf. For those of us in the area, many of the beaches are reporting normal conditions between Clearwater and Sarasota, so we might get some great beach days before winter after all.
Samuel Sheen, Lead Compliance Manager, Florida