Header image: Florida Sea Grant stock photo.

Last year’s red tide was on the minds of many Floridians for more than a year. Would-be tourists who saw images of coasts lined with dead fish canceled their vacations. Fishermen lost their catch. In some areas, coastal property sales plummeted.

In other words, red tides not only wreak havoc on our natural ecosystems, they also put a dent in Florida’s pocketbook.

Scientists and economists have been studying the economic impacts of harmful algal blooms like red tide for decades.

Chuck Adams Florida Sea Grant marine economics specialist
Chuck Adams

We had the chance to interview Chuck Adams, marine economics specialist with Florida Sea Grant, about why these harmful algal blooms place such a burden on Florida’s economy.

Need a refresher on red tide first? Visit this post by Florida Sea Grant to learn more: Understanding Florida’s Red Tide

Why are red tides so expensive?

Adams:  Karenia brevis, the organism that causes red tide, produces a neurotoxin called brevetoxin, which can harm and kill fish, birds and marine mammals. Economically important finfish are often among the hardest hit.

The same toxins can become airborne through nearshore wave action and create health problems for humans too. Airborne brevetoxins can create respiratory distress, burning of the eyes, coughing and other problems for individuals who are in the proximity or downwind of an intense red tide bloom.

These health issues and the associated foul smell make the beach and nearshore areas an unpleasant place to be during a red tide. As a result, businesses located near the water can experience significant disruption of sales during a bloom.

Waterfront lodging and restaurants, beach vendors, marinas, and other water-related businesses are particularly vulnerable to red tide events. The severity of the economic consequences will vary with the intensity, duration, and geographic scope of the red tide.

The Numbers Don’t Lie

  • The 2018 bloom resulted in $14.5 million being allocated for emergency funds to clean up beaches.
  • Last year, hotels on the Sanibel and Captiva islands in Lee County lost $8 million in revenue thanks to a 78% vacation cancellation rate between August and October. The area also lost $3.75 million in coastal property sales in 2018.
  • During the 2015-2016 bloom, the shellfish aquaculture industry lost $3.3 million in revenue.
  • In 2007, a red tide bloom resulted in $51 million in losses to the state’s restaurant and hotel sectors.
  • During the 2005 bloom, respiratory and digestive illnesses cost Floridians upwards of $1 million.

Is every red tide this bad?

Adams: Several studies conducted by the University of Florida and Florida Sea Grant have documented the fact that red tide events generate business losses and create economic hardship for water proximate businesses and coastal communities. The magnitude of such economic losses will depend upon the severity and duration of the red tide event.  How “bad” a red tide will be depends on many factors.

The blue-green blooms that impacted the Indian River Lagoon, the St. Lucie Estuary, Lake Okeechobee and the Caloosahatchee Estuary in recent years have also placed an economic burden on surrounding communities.

We know the symptoms of red tide well. We also know we can expect them in the future. In your opinion, what should be the main focus of future algae bloom-related research?

Adams: I think scarce public dollars would be better spent in the future on addressing the underlying problems that exacerbate red tide blooms, rather than repeatedly addressing the symptoms and confirming what is already known.

Although red tide is a naturally occurring phenomenon that originates offshore, ocean currents bring the bloom inshore where it feeds on excess nitrogen and phosphorus. These nutrients come from various sources along the coast including stormwater runoff, fertilizer runoff, septic tanks, and/or faulty wastewater systems.

If Florida’s coastal communities are to progress toward a safe and economically viable future, Floridians must address our contribution to the problem by reducing our nutrient inputs into nearshore waters and supporting research to further understand red tide and other harmful algal bloom causes, impacts and mitigation strategies.

To learn more about the economic impacts of red tide, visit:

 Economic Consequences of Harmful Algal Blooms: Literature Summary

To learn more about harmful algae blooms affecting Florida, visit:

Algae blooms affecting Florida

To get up-to-date information about red tide, visit: 

Current red tide status