Red Tide – Florida Red Tide and other Harmful Algal Blooms (HABs)


Florida Red Tide and other Harmful Algal Blooms (HABs)

K. brevis, the single-celled, harmful algae that causes Florida red tide, occurs naturally in background concentrations in the Gulf. However, its cells can proliferate to numbers that scientists categorize as “very low” to “high.”

Water samples collected along the Sarasota County coastline by the Sarasota Healthy Beaches program on Monday, Sept. 28, and analyzed by Mote Marine Laboratory, showed K. brevis cell counts elevated to low in New Pass, adjacent to City Island, and along Siesta Beach and Turtle Beach on Siesta Key. In addition, very low counts were found that day in samples along Longboat Key and the Ringling Causeway, three sampling sites along Lido Key, near North Jetty in Nokomis, at five sampling sites along Venice and at Manasota Beach. Any counts of K. brevis algae above background are a good reason for scientists to watch closely and for the public to get familiar with the sources of updates on harmful algae.

As of Tuesday morning, Sept. 29, Mote’s Beach Conditions Reporting System ( was NOT showing respiratory irritation along monitored beaches in Sarasota or Manatee counties, or other participating areas.

A brief update to last week’s statewide, report from FWC Wednesday, Sept. 30, followed by the next full report Friday, Oct. 2 at

Source: Red Tide – Statewide Status