Red Tide Bloom Continues to Impact Southwest Florida

The worst red tide to impact Florida since 2007 continues to wreak havoc on our southwest gulf beaches. The bloom started at the end of September and now stretches for 140 miles from Pinellas thru Collier County.

In mid-January, the highest concentrations of toxins from the bloom were found off Sarasota County shores with dead fish washing ashore and respiratory problems for beachgoers. Some beachgoers experienced coughing, sneezing, scratchy throat or teary eyes, effects that are temporary and stop once you leave the beach. Red Tide was reported at Lido Key, Siesta Key, Holmes Beach and as far north as the tip of Anna Maria Island.

Sarasota County workers along with nonviolent offenders enrolled in the Sarasota County sheriff’s offender work program removed dead fish in a clean up effort at county beaches.

Florida red tide blooms are caused by a single cell algae called Karenia brevis. They are naturally occurring at very low levels, usually about 30 miles offshore. Typically during the fall, ocean currents move the red tide to the coast. If the conditions are right, they proliferate into a toxic bloom.

Scientists are still trying to pinpoint just how blooms are triggered, but theorize that it is a combination of changing wind patters pushing red tide closer to shore, nutrient laden runoff fueling the inshore blooms and the red tide algae’s natural growth cycle.

The map was provided by the Florida Fish & Wildlife Conservation Commission and shows the period from January 14th to January 25th.

2 comments… add one
  • jason Mar 2, 2013, 1:27 pm

    ‘Nutrient laden runoff’ would imply fertilizer, sewage, etc. (people)? That is something that can be verified with lab experimentation, and should be solvable via improved infrastructure and regulations on chemicals in products that contribute to the runoff issue? Has there been research on SW FL population, evolving ‘landscaping demographics’, and the (apparent) increase in red tide activity?

    • colleen Mar 4, 2013, 3:54 pm

      Pollution is broken down into 2 categories- ‘point source’ which are things that are obvious polluters- sewage outfall pipes that go right into the ocean is a good example. Non point source are things that sort of leach into the water- fertilizer is a good example of that- you cannot pinpoint who’s yard it came from.

      Sarasota County implemented a fertilizer ordinance in 2007 to try to minimize pollution from fertilizer.

      Mote is in the final stages of analyzing a series of 11 experiments addressing the nutrient issue. They placed a series of different nutrient combinations in containers, added both the red tide organism and the other phytoplankton found in the water (since they consume nutrients as well) and monitored the growth over 48 hours. The final experiment with a dense, natural red tide bloom was conducted in November- the analysis’s are underway at this time. When the final results are in, Mote will publish on its website, in the scientific literature, and promote this key information to the media.

      Thank you for your comment.

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