Red Tide Red Drift Algae Return, Town Begins Clean Up


For most of 2019, Southwest Florida and Fort Myers Beach avoided the water quality issues that plagued our region last year. Over the past week, however, Red Tide returned to local waters, with Red Drift Algae once again on Fort Myers Beach. Are these typical early fall outbreaks or reasons for additional concern?

“The short answer is there is nothing typical anymore,” stated Calusa Waterkeeper John Cassani. “There are reoccurring trends in the works now as, to me, Red Tide blooms are increasing in duration and frequency, though this one does fall right into our usual fall pattern. The atmosphere however is slowly warming and so is the water, and those drive changes in our environment, so what we thought of as typical is not anymore.”

When considering any link to the recent Tropical Storm Nestor, “the bloom started well before Nestor,” Cassani related, “so there is no reason to believe Nestor made it any worse, but the truthful answer is we just don’t know! There are many moving parts at work in our current environment, so it is difficult to say which ones provide the most influence. Nestor’s onshore winds toward the coast pushed the near-surface water toward the beach and back bay, making it a problem, and the accompanying rainfall moved a lot of nutrient enrichments into the water, but it’s hard to say how much each influenced the current situation.”

Red Drift Algae piles up on the beach near the Connecticut St. access on Monday, October 21, 2019. Some dead sea life and litter were mixed with the Red Drift Algae.

Cassani explained, “Red Drift Algae is a macro-algae, meaning you see it with the naked eye, and anyone who spends any significant time in Southwest Florida knows what it looks like when piling up on the beach. What makes it more abundant then we previously remember is oceans have much more nutrient enrichment and when you combine that with warming water, that fuels its growth, in my opinion, so we are seeing another form of sargassum that some scientists believe responds to nutrient enrichments in the near-surface waters and is now becoming a huge problem. The Gulf Stream picks it up, moves it and deposits it on beaches.”

$64,000 Question

As for increased health risks, “If you agree there are more severe blooms that last longer, this should concern everyone,” offered Cassani. “We are just now understanding what breathing in brevetoxins can do to our health. If you are visiting from Minnesota and you breathe in brevetoxins at the beach, then return north, there is probably not much risk, but if you live here near the water year-round with exposure every fall, what happens to your health is the ‘$64,000 Question,’ and that becomes more problematic with our older population! Unfortunately, we still do not have that answer.”

Cassani cautioned people not to confuse 2019’s relatively clear water with cleaner water. “Water transparency as a true indicator of clean water is basically a fallacy; just because you cannot see or smell a pollutant does not mean it is not there. Another misconception is just because we have not yet had any significant water quality issues throughout 2019 does not mean everything is alright, as people after last year are in a way desperate to think that all is well. Personally and professionally, I do not see that improvement, even though the general perception is water quality is clearing up. I am reluctant to say we are out of the woods at this point, as we recently had over 30 endangered sea turtles wash up dead on area beaches, so that is not good. Remember we had cyanobacteria blooms back in May, and even though they were not as bad as in 2018 and lasted just a few weeks, they still had an effect on our ecosystem and potentially on public health.”

Cassani worries that people are losing the momentum from 2018 for clean water. “If you are waiting for the Florida Legislature to fix these problems, that might be a long wait! Governor Ron DeSantis made a big splash with water quality right after his election, and while the Legislature threw a lot of money at it this year, they did not implement many policy changes to promote clean water. I thought 2016 would be the biggest election of my life for clean water, then 2018 for sure, but now I think it will be 2020, so we need everyone to not only vote but make good decisions at the ballot box!”

Town Actions

The Town of Fort Myers Beach has initiated clean-up efforts. “The Red Drift Algae area of concern is from the Red Coconut RV Park to Hercules Drive,” explained Town Manager Roger Hernstadt in a statement released on Monday, October 21. “Staff has been removing as much as they can and pushing the algae to the water’s edge, hoping Mother Nature will carry it out during the next high tide. We have ordered five 20-yard dumpsters in route that can be filled tomorrow and removed. We have contracted for one truck and driver tomorrow to help with removal. Coconut Drive and Hercules Drive beach accesses are closed to the public as they are staging areas for removal. Environmental staff has been communicating with the Florida Department of Environmental Protection regarding authorizing the use of heavier equipment. Crews will be on-site in the morning to assess and begin operations again.”

On Tuesday, October 22, Hernstadt released: “Significant accumulation of Red Drift Algae and storm debris (sponge, shell, mangrove seedlings, fish, crab, sea urchins and litter). The worst part is from Hercules Drive to Connecticut Street. Algae thins as you go west northwest to the Red Coconut, but still significant amounts of debris. This was at mid-tide this morning; we will see the full extent at low tide at 3 p.m. Public Works crews were able to thin out a lot of the large clumps of the Red Drift Algae yesterday. Staff are removing the algae from Connecticut Street to Hercules Drive. Hercules and Coconut beach accesses remain temporarily closed as they are being utilized for staging of the dumpsters.”

Red Tide Basics

Florida Red Tide is an elevated concentration of a microscopic algae, most commonly Karenia brevis (K. brevis) that grows in salt or brackish water. It is not the same as Red Drift Algae, which is a macro algae that looks like seaweed that washes onto the beach. Red Tide can only be seen under a microscope, though if the concentration is high enough the water can take on a red or brown color, but water can also be clear even with a bloom.

FWC Red Tide testing map October 23, 2019. Graphic courtesy of FWC.

While Red Tide has been documented since Spanish galleons sailed the Gulf of Mexico, much is unknown about the blooms. Scientists say that the blooms form out in the Gulf. If they drift toward land, nutrients in the water can ‘feed’ the blooms.

The Florida Fish & Wildlife Conservation Commission (FWC) states that Red Tide can be harmful to humans and animals. K. brevis produces brevetoxins that can lead to fish kills. Those with weakened immune systems or respiratory conditions such as asthma, emphysema or COPD are at increased risk of respiratory irritation, especially if the wind is blowing onshore.

Advice on swimming in water with known Red Tide is mixed. The FWC advises that swimming is safe for most people, but can cause skin and eye irritation. They advise anyone experiencing irritation to leave the water and shower thoroughly. Others advise avoiding water affected by Red Tide and seeking out another beach. Do not swim among dead fish due to harmful bacteria. Keep pets away from Red Tide.

The current Red Tide bloom first appeared in FWC testing on September 25 offshore Fort Myers Beach and in Estero Bay. FWC recent sampling locations from Charlotte County to Collier County show results ranging from “not present” to “high” (over 1 million cells/liter). Fort Myers Beach locations were in the medium range with sampling from Lynn Hall Park and Lovers Key State Park on October 16. Medium levels are 100,000 to under 1 million Karenia brevis cells per liter. High levels (> 1 million cells/liter) were found in Pine Island Sound on Oct 21.

To see current FWC red tide reports, visit: