Please ensure Javascript is enabled for purposes of website accessibility

Red tide organism count elevated in Southwest Florida

Mote Marine Laboratory and other wildlife agencies continue to monitor the levels.

  • By
  • | 10:56 a.m. March 9, 2018
Previous red tide effects washed these fish on to shore. File photo
Previous red tide effects washed these fish on to shore. File photo
  • Longboat Key
  • News
  • Share

Over the past week, counts of the red tide algae, Karenia brevis, have been elevated in coastal waters.

Researchers from Mote Marine Laboratory and various state, local and federal agencies are monitoring the levels.

In the past week, K. Brevis was observed in background concentrations in one sample from Pinellas County and one sample from Manatee County; background to medium concentrations were found in 22 samples from or offshore Sarasota County, 12 samples from Charlotte County, 17 samples from or offshore Lee County and eight samples from Collier County.

K. Brevis is a single-celled alga that occurs naturally in the Gulf of Mexico, a release from Mote said. Higher-than-normal concentrations of the algae can include “very low,” “low,” “medium,” and “high” levels.

Elevated concentrations can cause respiratory irritation in humans and can kill fish, Mote’s statement said. Red tide symptoms usually stop when a person leaves the affected area, however people with asthma, COPD or other chronic respiratory conditions are cautioned to avoid active areas, Mote said.

Algae distribution, currents and winds can factor into the whether or not red tide effects are noticeable.

Water samples are collected weekly from 16 locations in Sarasota County by the Sarasota Healthy Beaches program of the Florida  Department of Health. Mote then analyzes those for K. brevis, the statement said.

Mote has a free app, Citizen Science Information Collaboration, that allows users to report when and where they experience possible red tide effects or see discolored water or dead fish.

FWC’s statewide red tide status reports are typically updated every Friday afternoon. Visit for the updates.