Red Tide Causes Sickness Along Gulf Coast

Source: steffstarr - 123RF

Florida – Following the littering of beaches with dead sea life as a result of naturally-occurring toxic algae, Florida Governor, Rick Scott, has declared a state emergency specifically for the counties of Collier, Lee, Charlotte, Sarasota, Manatee, Hillsborough, and Pinellas.

The so-called “Red Tide” has devastated marine life on Florida’s Gulf Coast this summer. Florida Fish and Wildlife Conservation Commission said in a statement, “In Florida and the Gulf of Mexico, the species that causes most red tides is Karenia brevis, often abbreviated as K. brevis. To distinguish K. brevis blooms from red tides caused by other species of algae, researchers in Florida call the former the ‘Florida red tide’.”

The area is no stranger to red tide events. “Red tides were documented in the southern Gulf of Mexico as far back as the 1700s and along Florida’s Gulf coast in the 1840s”, says the Commission, adding, “Fish kills near Tampa Bay were even mentioned in the records of Spanish explorers.”

This summer’s red tide has already caused the deaths of hundreds of sea turtles, as well as large fish like goliath grouper and even manatees. In places like Longboat Key, more than 5 tons of dead fish have been removed from beaches.

This week, nine dead dolphins were found in Sarasota County. Marine biologists are investigating whether the deaths are related to red tide.

Red tides can also cause respiratory irritation for humans. “For people with severe or chronic respiratory conditions, such as emphysema or asthma, red tide can cause serious illness,” officials explain.

The toxic algal bloom can last as little as a few weeks or longer than a year, according to the Commission, which notes that red tides can even subside and then reoccur. “The duration of a bloom in nearshore Florida waters depends on physical and biological conditions that influence its growth and persistence, including sunlight, nutrients, and salinity, as well as the speed and direction of wind and water currents,” it says.

The red tide can be found in bays and estuaries but not in freshwater systems such as lakes and rivers. The Commission says, “Because K. brevis cannot tolerate low-salinity waters for very long, blooms usually remain in salty coastal waters and do not penetrate upper reaches of estuaries. However, other harmful algae, including cyanobacteria (blue-green algae), typically bloom in freshwater lakes and rivers.”

Last month, Gov. Scott declared a separate emergency to combat algal blooms caused by Lake Okeechobee water discharges from the Army Corps of Engineers.