Hundreds of dead fish line Siesta Key beach. Red tide may be heading to Manatee next

Siesta Key was swamped by the smell of decomposing algae and fish on Thursday, and the shores of Manatee County may soon fall victim to the same fate, a result of this year’s red tide outbreak.

“I don’t know if I’m going to come back again,” said Gugu Garanda, who visited Siesta Key Beach from Tampa on Thursday with her husband. “We’ve come here at least 10 times and this is the first time I’ve ever seen anything like this.”

They left about 15 minutes later.

Hundreds of dead fish lined the shore of the beach alongside the brown water. The rotten smell, along with swimming being prohibited, resulted in an empty beach in the middle of the summer.

Farther to the south, red tide has been blamed for the deaths of thousands of fish, as well as sea turtles, manatees and other marine life off southwest Florida beaches.

The microscopic organism behind red tide, Karenia brevis, exists offshore throughout the year. It only becomes a problem when the algae blooms at high concentrations, said Robert Weisberg, a professor of physical oceanography at the University of South Florida.

But will it travel a little north and reach Manatee County beaches? Weisberg thinks so.

Such blooms, he said, could reach areas such as Longboat Key and Anna Maria Island within the next few days.

”This year has been a bad year. It started off as a bad year and I think it’s just going to get worse,” he said.

Red tide FWC 0801.jpg
A red tide status map realeased Aug .1 showed high concentrations of Krenia brevis, which causes Florida’s red tide, as far north as Saraosta County. Florida Fish and Wildlife Conservation Commission

An Ohio couple visiting Siesta Key on Thursday said the beach smelled like the “seafood section of a Kroger.”

Laura Hartzell, who is on vacation from Illinois, stopped by the beach with her nephew and grandson.

“We were just on Treasure Island a few days ago and it was beautiful up there,” she said as she covered her mouth from the smell. “We were able to swim and everything. It’s such a shame.”

Several factors likely aggravated the conditions this year, including heavy rainfall and the release of water from Lake Okeechobee, Weisberg said. Several offshore conditions also played a part, along with the fact that cells from last year’s outbreak are still present this year.

Each factor merged to create the hurricane of algae blooms. The metaphorical storm originated offshore, Weisberg said, and it appeared in the form of foul smells, irritating conditions and dead marine life.

Other organisms, which are not harmful, will sometimes outgrow the red tide. But when Karenia brevis begins to bloom at high concentrations, it tends to gain steam, Weisberg said.

This year’s outbreak started early, as most blooms appear in September or October.

“Once it does, it makes toxins and it kills fish, and the nutrients from the dying fish then feed more of these red tide organisms,” he said. “They’re just nice and happy because they’re living in their own grocery store.”

Weisberg heads the Ocean Circulation Group, which partners with the Florida Fish and Wildlife Conservation Commission to track water movement and the trajectory of red tide.

It’s hard to conduct regular offshore testing without sustained funding, Weisberg said. His researchers are unsure why the blooms eventually disappear.

“The good news is, the last time I went public with a forecast, I was wrong,” he said. “The bad news is, I don’t think I’m wrong this year.”

A midweek red tide status update from FWC published Wednesday noted background concentrations of the Florida red tide organism Karenia brevis was found in samples from Manatee and Pinellas counties.

Harmful Algal Bloom conditions were reported as “high” in northern Sarasota County all this week, according to an National Oceanic and Atmospheric Administration conditions report. Conditions were reported as far south as central Collier County, where conditions were listed as low.

Respiratory irritation was reported over the last week as close as Siesta Key, but also at Lido Key, Manasota, Nokomis and Venice beaches in Sarasota County. Fish kills were also reported on multiple Sarasota County beaches, according to the FWC report.

Dead fish have yet to be reported on Coquina or Manatee beaches on Anna Maria Island.

The Florida Fish and Wildlife Conservation Commission also says that a northern movement of red tide may be in the cards.

“It does look like some northern movement is possible but it will really depend on the weather such as the wind and the current and how that plays out this weekend,” FWC public information coordinator Melody Kilborn said.

The FWC plans to release another red tid report by the end of the day on Friday.

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