Table of Contents
If you want to escape the cold and vacation in Florida this winter, in addition to finding a hotel, restaurants, and activities, check for red tides. Scientists call them harmful algal blooms or “HABs.”
Note: Even though this is a growing problem, the majority of Florida beaches are free of red tides.
HABs are naturally occurring in coastal areas and not all of them are harmful. Thousands of algae in fresh and ocean waters provide food to fish and other sea creatures.
The HABs we need to watch out for contain a higher-than-normal concentration of Karenia brevis, which produces brevetoxins that can kill fish and marine animals. It also harms humans, especially if you have asthma or another respiratory illness. These microscopic algae also makes shellfish dangerous to eat.
Julie Odenweller, who has asthma, experienced it firsthand. Shortly after moving to Sarasota, her doctor said she could strengthen her lungs by starting to run. She ran a triathlon along the beach and “afterwards I ended up with an infection,” she says. “My doctor attributes it to the red tides.”
See also: The 5 Best Eco-Friendly Beach Resorts
When is red tide season in Florida?
In Florida, HABs begin in late summer or early fall and last through February or March. This past year, seven tons of dead fish washed ashore Sarasota beaches due to red tides. Swimmers reported skin infections and people with lung diseases reported trouble breathing. Some wind up in the emergency room.
“No one should get sick from a day at the beach,” Barbara Kirkpatrick, senior scientist at Mote Marine Laboratory and Aquarium, says. “The Florida red tide is a small microscopic harmful algal bloom that produces a really potent neurotoxin. Beachgoers inhale that toxin; that’s actually a trigger for asthma. We had a massive dolphin die off and the manatees are inhaling these toxins and eventually do perish.”
Florida’s tourism site answers the question, “Is swimming okay?” by stating, “Yes, for most people. However, in some people, red tide can cause skin irritation and burning eyes. Use common sense – if you are particularly susceptible to irritation from plant products, avoid red tide water. If you experience irritation, get out thoroughly wash off. Do not swim among dead fish because they can be associated with harmful bacteria.”
Distinguishing harmful from safe algal blooms
Large concentrations of algal blooms turn the water a slightly red color. That doesn’t mean the algal blooms are harmful. “There’s a lot of confusion,” Andrew Reich, scientific advisor, Florida Bureau of Environmental Health, says. “Not all algal blooms are harmful and red tide is hard to see if you’re looking at it from the beach. You can’t smell it either. If it’s in the air, you may feel a tickle in your throat or have a cough.”
People who swim in waters not knowing red tide is present can swallow it as well. It doesn’t have a specific taste. If it winds up in shellfish, you can’t taste it either.
An economic drain
“Red tide can be a huge drain on the economy of these communities,” Cynthia Heil, director of Mote’s Red Tide Institute, says.
A number of studies conducted by the University of Florida and Florida Sea Grant found hotels in Sanibel and Captiva islands lost $8 million in revenue due to a 78 percent vacation cancellation. A 2018 red tide bloom resulted in a $14.5 million beach cleanup allocation.
It’s impacted many of Florida’s coastal businesses. “It’s difficult to predict how long a red tide will last and each day means losses for local restaurants and businesses,” Reich explains.
A seafood problem
Restaurants are careful with their catch because it’s tested for toxins. The problem lies with tourists trawling oyster beds. Bird and sea turtle mortality rises during red tide season because they eat infected fish. Dogs also get sick if they ingest infected shellfish.
Some tourists trawl or carry a bucket to catch shellfish, which is a problem because eating shellfish that ingested HABs are harmful. You can’t cook out the toxins. Even deep frying won’t kill the toxins.
It’s not just the toxins
HABs that don’t produce toxins can also be harmful because they deplete oxygen from the water. They block sunlight needed for plants and sea creatures at lower levels of the ocean and can clog fish gills.
Hurricanes can end or worsen red tides
Sometimes hurricanes lengthen and strengthen red tides. Hurricane Katrina had the opposite effect. Its winds pushed Gulf currents in such a way that it reduced the tiny organisms that poison marine life.
Some hotel workers will share information about red tides. Others, unfortunately won’t. The same goes for restaurant and sightseeing staff. They’re unwilling to share information because if they tell you it’s a problem, obviously, you’ll change your travel plans and avoid the area.
Constantly monitoring the situation
For the past several years, scientists at the National Oceanic and Atmospheric Administration (NOAA) have studied red tides. Their goal is to provide advanced warnings to communities so they can prepare to deal with the negative environmental impacts and health effects.
Lifeguards on Florida beaches and citizen scientists are also doing their part by working with numerous agencies to spot and report red tides. “Volunteers provide water samples and are working with NOAA scientists,” Reich says.
NOAA also uses satellite imagery to detect, forecast the intensity, and locate red tides. The satellites also track the movement of red tides. The imagery lets scientists know where abnormally high amounts of red tide exist. Unfortunately, it can’t distinguish between HABs and nontoxic algal blooms.
Florida Fish and Wildlife has a daily red tide map showing where red tides exist. Many parts of Florida are fine. You just don’t want to spend your vacation in an area with a large concentration of red tides.
Florida is 160 miles wide and 500 miles long. Most of the Sunshine State is free of red tides. You’ll only want to avoid red tide areas.