How did Hurricane Michael impact red tide? Here’s what the experts had to say

A red tide is destroying wildlife across Florida’s southwest coast

An ongoing red tide is killing wildlife throughout Florida’s southwest coast and has left beaches littered with dead fish, sea turtles, manatees and a whale shark. Additional footage courtesy of Southwest Florida TV via Facebook.
Up Next
An ongoing red tide is killing wildlife throughout Florida’s southwest coast and has left beaches littered with dead fish, sea turtles, manatees and a whale shark. Additional footage courtesy of Southwest Florida TV via Facebook.

It’s too soon to tell if the devastating power of Hurricane Michael impacted or dispersed the bloom of algae that has plagued Florida shores, including those in Manatee County and Anna Maria Island with red tide.

Mote Marine Laboratory spokeswoman Stephannie Kettle said Thursday that water samples will be collected early next week to evaluate the concentration of Karenia brevis cells, the organism that causes red tide, in waters off the west coast of Florida.

Until then, it’s unclear what impact, if any, Hurricane Michael had on the algae bloom, Kettle said. The bloom has lasted nearly a year, but has been noticeable in Manatee County for about two months.

Since August, red tide has strongly impacted sea life, business, tourism and the environment on Anna Maria Island.

Florida International University research associate professor Tom Frankovich also said it’s a “wait and see” situation for what will happen to the lingering red tide bloom.

Frankovich said there are possibilities — some short-term and some long-term — to how Michael could have impacted the bloom.

“In the short term, you can think of the hurricane as taking ocean water, putting it in a blender and spitting it all out,” Frankovich said.

He said it could break up some of the bloom and change its distribution, maybe even disappear. But, the rough waters and intense winds associated with the hurricane could also disperse the toxins in the algae into the air and transfer it further inland.

There are more possibilities in the long term, but “we just don’t know” what could happen, Frankovich said.

Freshwater coming off the coast would decrease the occurrence of the bloom because it prefers seawater, he said, but all the land-based nutrients are also being flushed into the system, which could initiate or increase existing blooms.

Waterfront restaurants are spreading the message that there may be red tide, but they are open for business.

A midweek update on red tide from the FWC showed “patchy concentrations” of the algae along the Gulf shore between Pinellas and Lee counties.

In some parts of Manatee County, FWC noted a decrease in cell concentration as well as in parts of Sarasota County. Charlotte, Lee and Collier counties also saw a decrease in cell concentrations.

The K. brevis cells continued to be observed in Northwest Florida and on the state’s east coast in medium and high concentrations as of Wednesday’s update.

Manatee, Sarasota and Pinellas counties all had reports of fish kills either in or offshore, according to FWC. Respiratory irritation was also reported in several Southwest Florida counties, including Manatee.

Kettle said last week’s offshore winds kept the red tide bloom away from beaches, which led to lower cell counts in the samples over the past week and a half. But when Hurricane Michael moved through the Gulf on Wednesday, the winds were shifted back onshore, Kettle said.

“So we’ll see how that affects the bloom,” she said, noting they won’t know until the samples are collected for red tide cell counts next week.

Until then, beach conditions are updated daily on Mote’s Beach Conditions Report website and a daily sample map from FWC shows a daily red tide cell count status in waters across the state.

As of Thursday, Mote officials reported Manatee Beach showed no red drift or dead fish, but slight respiratory irritation and dark water color. On Coquina Beach, red drift was reported thick with some dead fish, intense respiratory irritation and dark water.

The FWC’s daily sample map indicated Thursday that Manatee and Sarasota counties had mostly background concentrations of the K. brevis cells per liter, and one area with a low concentration of cells.

Pinellas County beaches showed medium and background concentration counts. However, Sunshine Beach in St. Petersburg showed high concentrations.

Kelli Hammer Levy, director of Pinellas’ environmental management division, told the Tampa Bay Times nearly every Pinellas County beach was “impacted by dead fish” on Thursday morning.

Read Next

A vast majority of east coast samples showed low to background concentrations of K. brevis cells per liter. Medium concentrations were noted in St. Lucie, Martin and Miami-Dade counties.

In the Panhandle, hardest hit by Hurricane Michael on Wednesday, only Bay County locations showed anything above background concentrations of the algae, and even then it was considered low-level by FWC.

A red tide that has sloshed up and down the Gulf Coast for nearly year, leaving a wake of dead sea life, murky water and stinky beaches, has now landed on the state’s most crowded shores including Miami-Dade County.

Frankovich said they “can’t predict anything yet” about what will happen to the red tide bloom.

Scientists with FWC and The University of South Florida predict “a reversal from northern to southern transport of surface waters and net southeastern movement of subsurface waters for most areas over the next three days” between Pasco and northern Monroe counties.

But looking at history, Frankovich said the last red tide bloom that lasted as long as the present one was in 2005. The year before, Florida experienced four hurricanes: Charley, Francis, Ivan and Jeanne.

Judging from that perspective, Frankovich said it “doesn’t look good.”

The next complete red tide status report from the FWC will be released Friday.