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Red Tide mega thread! Read here for everything you should know

Dead fish washing up on shore, even sizes and animals larger than the one pictured above.

Photo Credit: Sharon Karasick

Red Tide and the Problems it Raises

By: Wesley Schmidt ‘22, Hannah Evers ‘19, Isabella Emmett ‘22, Daniela Mayl ‘22

During recent months, the West Coast of Florida has been experiencing one of the worst Red Tide blooms observed in history.

This event affects the locals, the economy, and the environment in more ways than one would suppose. The real question at hand--is there any way to lessen the effects of this harmful algal bloom?

Red Tide is an HAB (harmful algal bloom). Scientists haven’t fully figured out what causes Red Tide, however, one theory is that some fertilizers containing high concentrations of nitrogen and phosphorus flow out into the gulf as runoff, causing the algae to be fed large quantities of nutrients. These algae overgrow and deplete the oxygen from the water.

After interviewing marine biology students at Riverview, what they had to say about how HAB’s (harmful algal blooms) affect the local and the Gulf of Mexico’s ecosystems was quite interesting. Emily Radcliffe ‘21 said scientists should focus on prevention.

“Mote and other labs should conduct research on how to prevent it, [Red Tide] but keep a close eye on the cause and effects,” Radcliffe said.

Eating certain foods during Red Tide can be dangerous to humans. Some seafoods like shellfish and shrimp can easily get infected via chemicals released from Red Tide. Consuming these contaminated shellfish can cause Paralytic Shellfish Poisoning in humans. Eating unaffected fish caught in the Gulf is not dangerous though.

As always, all seafood served in restaurants is closely monitored and quality controlled for safe consumption.

Red Tide can also cause respiratory problems that are usually short in duration. Fish aren’t the only affected creatures--any marine life within the area can be harmed.


Strewn apart dead fish coming up on shore.

Photo credit: Sharon Karasick

Red tide (What, Where, When, Why, and How)

By: Selena Gonzales ‘22, Imogen Evans ‘20, Maddy Boehm ‘21, Mira Miesner ‘20

For centuries, red tide has been a naturally occurring part of our coastal ecosystem. However, this year red tide has intensified. It has started to destroy the beaches, decrease the number of tourists, and is causing severe economic problems.

Public policy involves the principles, often unwritten, on which social laws are based. Science informs public policy regarding Red Tide by helping to regulate human behavior that makes Red Tide worse.

The media and scientific communities play vital roles in informing the public of recent news that could possibly affect them and their health.

This Red Tide outbreak has been spanning the Southwest Florida coast for ten months.

Going to the beach during red tide can cause many problems to the human body. It can cause irritation in the respiratory system, which means it makes it harder for people to breathe when they go to the beach or anywhere near the beach, according to Judy Ann Hallmark.

“It starts as an algae cyst offshore in the Gulf, replicates rapidly given the right conditions, then gets blown onshore when currents and winds create favorable conditions,” said Trey Austin ‘19.

Many are wondering about the connection between Lake Okeechobee and this particular Red Tide outbreak.

The dumping of the lakes water off both coasts is like adding fuel to the fire. When Red Tide is present, the nutrient run-off saturating the lake water feeds another algae (not the Red Tide Algae directly).

This algae bloom fixes Nitrogen so that Karenia brevis can devour it easily. “The lake water itself can’t directly influence K. brevis, because the organism cannot survive in fresh water.” Hallmark notes.


Katrin Rudge and Sharon Karasick out on the bay helping clean up Red Tide.

Photo credit: unknown

Managing HABs

By: Reid Bartkus ‘19, Hailey Gattorna ‘22, Zach Brook ‘22, Gianna Delissio ‘22

According to the U.S Census Bureau’s Statistical Abstract of the United States, about 58.67 million people visit the beach everyday yearly. Now that the Red Tide is infesting the waters of Florida, that number has declined.

The question that was asked, “How are harmful algae blooms detected and managed for human health?” wasn’t a problem for marine biology student Amelia Seger ‘20 to answer.

“Harmful algae blooms can be mitigated by not using fertilizer on our lawns because it runs into the ocean and pollutes the water,” Seger said.

Still, many people across the country are uneasy about this situation and how it could affect the reputation of the West Coast of Florida.

This is why scientists are going through to prevent another outbreak.

“Scientists put the water under a microscope and measure it by square inches and check for Karenia brevis,” explained marine biology student Zach McIntine ‘22.

The harmful algae blooms are currently being studied to prevent any dangerous outcomes for the human population. Scientists are still working to stop this wave of algae blooms from happening again in the future.


Red Tide — fatal to fish, foul to visitors

By: Madison Binkley ‘21, Sofia Boyle ‘22 and Alyssa Prezioso ‘22

Karenia brevis is a harmful algae bloom that is widely known as Red Tide. Physical, chemical, and biological factors, as well as human activities, contribute to HABs worldwide.

The rate of marine life death escalates during such an HAB.

During Red Tide, “The rolling death tally is 30 percent higher than the 5-year average,” according to an article published in the Palm Beach Post.

“There are three primary sources of human impact on nutrient levels in our ecosystems. Wastewater plants, stormwater runoff and atmospheric deposition can all add Nitrogen to ocean systems. Sarasota County has taken great measures to reduce the impact of wastewater plants, so the number one source of food for the algae from human activities is pollution through using fertilizers.

For example, when rain falls, the fertilizer in our backyard runs across the ground into storm drains and becomes runoff that enters our oceans.

Red Tide is also transferred through boats, by waste material in the bottom of the ships being transferred all throughout the ocean during their routes,” said Emily.

“Despite all the negative effects that humans attribute to this tide, there are things people can do to help it. There is a county ordinance that makes it illegal to use fertilizers during rainy, summer months. There is so much rain, very little of the fertilizer stays on people’s lawns.

Very few people know about the law or the impact though. Every small step we can take to reduce human factors may not end this tide, but greatly increase the chances of it being less severe in the future,” said by a senior that studies marine biology.

The student added “everyone’s actions matter in addressing this issue”.

Red Tide has posed as a large economic burden on the area. Not only does this tide bring in a stench and simply unpleasing sight, it is negatively affecting the economy. Sarasota brings in most of its income through tourists, and the money they spend to come see Siesta Key Beach. Red tide has drawn people away from the area, resulting in a decrease in revenue for the community.


Red Tide’s scourge

By: Daniel Lobo ‘22, Ethan Krafft ‘19, Rachel Hayes ‘21, Rylee Grover ‘22

Nobody likes the unpleasant stench of the infamous red tide. Sarasota’s world-renowned beaches were empty during the Labor Day weekend, as dead fish and other marine life littered the white sand, and the shore reeked of their corpses.

Red tide swamps the shores of Florida beaches nearly every year, causing the putrid stench of dead sea creatures to waft around the Florida coast. But what is red tide, and who does it affect? And, why is it so bad this year?

Essentially and simply, red tide is the rapid growth of Karena brevis, a phytoplankton known to cause Harmful Algal Blooms. While there are many kinds of phytoplankton, there are only a select few that actually cause these harmful blooms. One specifically, K. Brevis, is responsible for the Florida red tide that has been plaguing Gulf shores lately.

These algae produce a neurotoxin that barrages nerve tissue of sea life unlike other algal blooms that suck the oxygen out of the water. It’s devastating, not only for what lives underwater, but also for what lives above it.

There are many types of algal blooms around the world that can cause the same levels of tragedy for fish and mammals all the same. In the Gulf of Mexico alone, there are 50+ species that can harm even large creatures, such as whales and manatees, because of their overly floriferous characteristics. The colors produced can be quite beautiful despite the negative impact that they have on the organisms around them.

Despite that, K. brevis is so harmful to ocean life that it has even been known to kill sharks and the occasional whale. But it doesn’t impact small fish and larger fish the same way--because of their smaller size, it is easy for K. brevis to kill fish faster than larger marine life.


Red Tide and HABs and how they're affecting our city

By: Allison Housh ‘22, Emmalee Adams ‘22, Caroline King ‘22, Ja’Nylaa Crenshaw ‘22

Florida’s Gulf is being taken over by harmful algae that are killing the regional ecosystems.

The people are wondering--what is causing all the dead fish and stinky smell?

Harmful algal blooms, often known as HAB’s, are responsible. HABs are just as scary as they sound.

The National Ocean Service says that Harmful Algal Blooms occur naturally, but human activities disturb ecosystems and “seem to play a role in the increased occurrence of some blooms.”

Algae blooms take place when colonies of algae grow out of control while producing toxic effects on humans, sea life and the entire ocean environment.

They haven’t found an exact solution to HABs, but many researchers and scientists have been experimenting with ways to help solve this harmful algae bloom.

Marine biology student Hannah Mauer ’22 said Sarasota’s Mote Marine is working toward a solution.

“Mote Marine Laboratory is working on a clay ozone treatment, where they pour clay over the top of the water until it clumps to the algae and it sinks it. Then ozone breaks down the toxins,” Mauer explained.

Mote Marine is still running tests to make sure that it is safe.

Jennifer Lopez ‘19 mentioned a way to control Red tide which was very unexpected.

“Use less grass fertilizer. A lot less,” she said.

Since the chemicals homeowners put onto their lawns will eventually become runoff and get into the water, fertilizers are a significant part of the problem even when used by people who don’t live directly on the water.

These harmful HABs are greatly affecting Florida’s environment, economy and health. The Sarasota economy relies heavily on tourism which comes from the beaches.

When the HABs are in full force, people don’t travel to the beach or go to any of the stores or restaurants nearby. Red tide also greatly affects people’s health and can cause you to get rashes and respiratory issues.

Although scientists feel they are not even close to finding a cure for Red Tide, researchers, scientists, and even normal civilians are trying hard to get rid of it.

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