Discolored water and fish kills occurred along the Collier
County coast in July 2011. Investigations revealed blooms of the
nontoxic dinoflagellate Takayama tuberculata. An isolated bloom
appeared in Lee County with no negative effects reported.
The first Takayama
tuberculata blooms of 2011 on the west coast of Florida were
observed July 5 at Vanderbilt Beach and Naples Pier in Collier
County. Takayama tuberculata is a single-celled organism
belonging to a group of microscopic algae called dinoflagellates.
Wartlike bubbles on the bottom of the cell (Figure 1) make it very
distinct from other Takayama species.
Figure 1. Scanning electron
microscope image of Takayama tuberculata
Takayama tuberculata blooms have been documented along
Collier County annually since 2008. High concentrations of
T. tuberculata can deplete dissolved oxygen and
discolor the water red to brown. Blooms occur in the summer and
fall, though low concentrations of T. tuberculata
can be found year-round. Whether T. tuberculata
blooms in Florida produce toxins is undetermined. Analysis of water
samples collected from the July 2011 blooms showed no marine
biotoxins.
On July 18, two weeks after the first observed T.
tuberculata blooms, fish kills associated with low
dissolved oxygen concentrations were reported at Clam Pass and
Vanderbilt Beach. Many aquatic species washed up, dead or dying,
onto the county's beaches. Collier County officials warned
beachgoers to exercise caution due to the "large number of stressed
and dying animals in the surf zone that could cause injury if
stepped on." Local residents and county officials were surprised to
see the variety of creatures that normally do not appear in the
shallows, such as lobsters and nurse sharks (Figure 2), with the
patchy T. tuberculata blooms along the shoreline (Figure
3). Routine water sampling at the northern Collier County beaches
revealed that nontoxic diatom blooms of Hemiaulus
sp., Proboscia alata, and Nitzschia
closterium also were present there.

Figure 2. Nurse sharks at Vanderbilt
Beach on July 18, 2011
Photo credit: Rhonda Watkins, Collier County Pollution Control
Department
On July 18 and 19, satellite images from the University of South
Florida's College of Marine Science showed elevated
chlorophyll levels offshore of Collier County and along its coast,
indicating the presence of algal blooms. Water samples revealed
bloom concentrations of T. tuberculata at Lover's
Key State Park in Lee County on July 20, but no adverse effects
from this single bloom appeared to occur.
The following week, the FWC's Fish and Wildlife Research
Institute conducted an offshore sampling trip to determine the
extent of the blooms. Cruising up to 12 miles offshore of Lee and
Collier counties, staff noted cloudy water and high chlorophyll
concentrations. At a few locations, microscopic examination of the
waters showed blooms of coccolithophorids, microscopic algae that
can cause waters to appear cloudy. Offshore water samples indicated
very low concentrations of T. tuberculata and
patches of nontoxic diatoms, suggesting that the Takayama blooms
were confined alongshore.
Microscopic examination of water samples collected at Collier
County beaches on August 2 showed that while T.
tuberculata blooms were absent, there were blooms of
coccolithophorids and nontoxic diatoms at Barefoot Beach,
Vanderbilt Beach, and Naples Pier. By August 9, all
previously reported blooms were gone from Collier and Lee
counties.
Figure 3. Takayama
tuberculata bloom locations in Lee and Collier counties, July
2011
View images and learn more about HAB species in our Flickr
set.