Florida’s Toxic Algae Crisis

We’ve all seen the horrific pictures of marine animal carcasses washed up on Florida’s beaches. Animals emblematic of our state’s wildlife—such as manatees, dolphins, and sea turtles—have been turning up dead at alarming rates. The harmful algae blooms (HABs) darkening Florida waters are to blame. The HABs were worse last summer than they had been in at least a decade.[1] While thankfully the HABs have cleared in some areas of the state, they persist in others, and HABs will continue to be a reoccurring problem in Florida.[2]

This article will provide an overview of this crisis, discussing the microorganisms that make up HABs, what causes them to bloom excessively, and the harms they wreak. It will then address how the state government has responded to the current crisis and possible methods of curbing HABs in the future.

A canoe travels down an algae-ridden river in Florida. Credit: John Moran, via Wikimedia Commons.

What is a Toxic or Harmful Algae Bloom?

First of all, it is important to understand that there are two different types of HABs wreaking havoc: red tide caused by the microscopic organism Karenia brevis in gulf waters and blue-green algae blooms caused by a type of cyanobacteria in freshwater rivers and lakes (though technically classified as bacteria, these cyanobacteria are known as blue-green algae because they exhibit characteristics of algae). Although algae are present in these waters year-round, they are only harmful when they bloom excessively, producing toxins that are released not only into the water but also into the air.[3]

Why can Algae Blooms be Harmful?

Red tide produces neurotoxins (called brevetoxins). Marine animals are poisoned by the algae when they accidentally consume them. The toxins attack their central nervous systems, killing them or rendering them nearly comatose. People can also be sickened by ingesting the toxins; for example, contaminated oysters and clams can cause neurotoxic shellfish poisoning (NSP). When red tide toxins become airborne, beachgoers and coastal residents can suffer eye, nose, and throat irritation. People with respiratory conditions such as asthma can become seriously ill from exposure to these toxins.[4] These health effects of red tide are so widespread that they can be responsible for a significant increase in hospital admissions in coastal communities.[5]

Blue-green algae produces toxins, called cyanotoxins, that have similarly deleterious effects. Exposure to these toxins may cause symptoms in humans ranging from headache and sore throat to liver or kidney damage.[6] Animals that live in affected waters suffer, and pets as well as farm animals can get sick or die if they drink water containing toxic levels of algae.[7] Even when blooms are not toxic, they can reduce oxygen levels and block sunlight in bodies of water to the point that aquatic life dies out. These areas are known as “dead zones.”[8]

What is Causing HABs?

Toxic blooms and the associated fish die-offs on Florida’s Gulf Coast are natural phenomena, well documented since the 1840s and even reported as early as the 1500s by Spanish explorers. However, it appears that HABs have become more frequent, severe, and widespread in recent decades.[9] Indeed, the HABs that Florida has been struggling with over the past year are considered the worst in a decade.[10]

Climate change may be one culprit. Greenhouse gas emissions have increased global temperatures, including water temperatures, and HABs often thrive in warm waters. Climate change is also to blame for more extreme conditions—such as drier droughts and more frequent and intense storms—that may make HABs more difficult to control.[11] For example, some oceanographers predicted that Hurricane Michael would flush the red tide away, but instead the problem actually got worse in the weeks following the storm.[12]

Manmade changes to Florida’s landscape and hydrology also exacerbate HABs. The state used to be largely made up of wetlands, which allowed rainwater to run off more slowly and be naturally filtered into aquifers and estuaries. But now, in order to accommodate agriculture and development, the wetlands have been drained and water flow has been redirected by manmade dikes, canals, and levees. Development increases impervious areas, preventing rainfall from naturally soaking into the ground. Water now flows more rapidly into rivers and the Gulf of Mexico—off of impervious developed areas and channeled through manmade waterways. The water is thus unable to take part in the natural filtration cycle.[13]

The filtering problem is exacerbated by nutrient pollution from agricultural development. Citrus groves, sugar farms, and animal agriculture all use fertilizers such as phosphorus and nitrogen. Fertilizer use in Florida is particularly high because many crops can grow year-round here and the soil, composed primarily of sand, does not retain nutrients as well as other types of agricultural soils. When Florida waters are polluted by excessive amounts of these nutrients, the nutrients feed the algae and cause excessive—and harmful—algae blooms.[14] Sewage sludge dumped on farms as well as leaky septic tanks throughout the state also contribute to the pollution that fuels the algae blooms.[15]

What can be Done to Prevent and Control HABs?

HABs are difficult to predict and control. They naturally occur in Florida, and their duration and severity depends on unpredictable and uncontrollable factors like the weather.[16] Aggressively tackling the issue of climate change should be a priority in order to keep HABs in check.[17] But the most immediate and concrete factor that we can control is the nutrient pollution that is exacerbating the HAB problem. This can be accomplished in multiple ways. Nutrient pollution can be reduced at its sources, which include discharges from confined animal feeding operations and sewage treatment plants, as well as runoff from agricultural fields, roads, and stormwater. Already-polluted water can also be captured and treated. [18] Although these methods are already being implemented as part of Everglades restoration efforts, these projects will not be finished for decades and swifter action should be implemented.[19]

Long-term environmental monitoring programs are also crucial. Monitoring programs provide data on the HABs that is helpful in understanding how to control them. These programs are also vital for gauging whether restoration efforts are working.[20]

Finally, researchers are partnering with universities and state agencies to work on methods of mitigating HABs by killing off the toxic algae. [21] Experimental methods must be implemented with caution, however, because their effects on Florida’s ecosystem are yet unknown.[22]

How has Florida’s Government Responded to HABs?

Governor Rick Scott addressed the 2018 algae crisis by declaring a state of emergency and allocating $1.5 million in emergency funding.[23] Scott directed

the Florida Department of Environmental Protection and the Florida Fish and Wildlife Conservation Commission to increase water quality testing. He arranged for state agencies to help local businesses harmed by the HABs, and he set up a grant program to help cover the cost of environmental clean-up.[24]

But critics argue that this was too little, too late. As the director of the Florida chapter of the Sierra Club, Frank Jackalone, explains: “Rick Scott is the governor of Florida and has had the power to enforce the Clean Water Act in the state. He could have enforced pollution regulations. Instead, he cut back funding, rolled back regulations, and eliminated a large part of his enforcement staff.” It is true that, under Scott’s leadership, Florida environmental agencies’ budgets were slashed.[25] Programs monitoring water quality have dwindled, leaving researchers without important data to predict and understand HABs.[26] The issue of climate change was not addressed.[27] Scott signed the repeal of a law requiring septic tank owners to get an inspection every five years, and critics say that leaky septic tanks are a substantial contributor to the pollution that feeds HABs statewide.[28]

But Florida has a new governor, Ron DeSantis, who took office in January. He has vowed to tackle Florida’s environmental problems—including the HAB crisis—head-on. Shortly after taking office, he asked the board members of the South Florida Water Management District (SFWMD) to step down because he believed they had failed to appropriately address the HAB crisis.[29] He signed Executive Order 19-12, calling for $2.5 billion the be spent over the next four years on restoring the Everglades and protecting water resources; establishing a Blue-Green Algae Task Force; instructing SFWMD to speed up work on a reservoir to protect the Everglades from pollution; creating the Office of Environmental Accountability and Transparency to oversee scientific research and make sure that all agency actions are consistent with environmental priorities; and appointing a Chief Science Officer to organize and prioritize current scientific research to address pressing environmental concerns.[30] As he unveiled these sweeping plans, Gov. DeSantis said: "I pledged I would take action, and today, we are taking action . . . I think this is something that can unite all Floridians."[31]

Environmentalists still have concerns because DeSantis has declined to address the causes of climate change and therefore does not have a plan to combat those underlying causes. But there is no question that DeSantis’s reforms are a good start. Everglades Foundation CEO Eric Eikenberg described DeSantis’s plan as a “bold first move,” and Audubon Florida Executive Director Julie Wraithmell said, “It’s a little bit like Christmas morning to see all of the things in this executive order.” As Frank Jackalone put it: “In his first week in office, Gov. DeSantis has done more to address Florida’s water quality crisis than Gov. Rick Scott did in eight years.”[32] Hopefully, with these changes, Florida will be better equipped to handle the persistent problem of HABs.

*Gretchen Myers is a member of the Animal Law Section's Executive Council. She graduated from Stetson University College of Law in 2009, and currently serves as a staff attorney at the Second District Court of Appeal.

[1] Priya Shukla, “Why is Florida Experiencing its Most Toxic Algae in a Decade?” Forbes, Aug. 10, 2018, https://www.forbes.com/sites/priyashukla/2018/08/10/why-is-florida-experiencing-its-most-toxic-algae-bloom-in-a-decade/#5a615afc587e

[2] See FWC, “Red Tide Current Status,” https://myfwc.com/research/redtide/statewide/ (last accessed Feb. 10, 2019); FDEP, “Algal Bloom Sampling Results,” https://floridadep.gov/dear/algal-bloom/content/algal-bloom-sampling-results (last accessed Feb. 10, 2019).

[3] Joel Achenbach, Kate Furby, and Alex Horton, “Florida declares a state of emergency as red tide kills animals and disrupts tourism,” The Washington Post, August 14, 2018, https://www.washingtonpost.com/news/speaking-of-science/wp/2018/08/14/red-tide-algaes-deadly-trail-of-marine-animals-has-triggered-a-state-of-emergency-in-florida/?utm_term=.d3f988ee0adf; EPA, “Harmful Algal Blooms & Cyanobacteria,” https://www.epa.gov/water-research/harmful-algal-blooms-cyanobacteria (last accessed Feb. 12, 2019).

[4] Maya Wei-Haas, “Red Tide is Devastating Florida’s Sea Life. Are Humans to Blame?” Nat’l Geo., Aug. 8, 2018, https://www.nationalgeographic.com/environment/2018/08/news-longest-red-tide-wildlife-deaths-marine-life-toxins/; National Oceanic and Atmospheric Administration, “Red Tide in Florida and Texas,” Fall 2018, https://oceanservice.noaa.gov/news/redtide-florida/; Florida Health, “Red Tide Blooms,” http://www.floridahealth.gov/environmental-health/aquatic-toxins/red-tide.html (last accessed Feb. 12, 2019).

[5] John Niedzwiecki, “A Blooming Problem: How Florida Could Address the Causes and Effects of Red Tide,” Georgetown Environmental Law Review Blog, Aug. 29, 2018, https://www.law.georgetown.edu/environmental-law-review/blog/a-blooming-problem-how-florida-could-address-the-causes-and-effects-of-red-tide/

[6] Environmental Protection Agency, “The Effects: Dead Zones and Harmful Algae Blooms,” https://www.epa.gov/nutrientpollution/effects-dead-zones-and-harmful-algal-blooms (last accessed Feb. 12, 2019); Environmental Protection Agency, “Health and Ecological Effects,” https://www.epa.gov/nutrient-policy-data/health-and-ecological-effects#what1 (last accessed Feb. 12, 2019).

[7] Karl Havens, “What is causing Florida’s Algae Crisis?” PHYS.org, Aug. 10, 2018, https://phys.org/news/2018-08-florida-algae-crisis.html; see also Kansas State University, “Veterinary Toxicologist Warns of Blue-Green Algae Dangers to Livestock, Pets,” PHYS.org, June 26, 2018, https://phys.org/news/2018-06-veterinary-toxicologist-blue-green-algae-dangers.html#nRlv; Craig Patrick, “Algae-filled water that poisoned South Florida dogs now being pumped underground,” Fox 13, Nov. 19, 2018, http://www.fox13news.com/news/fox-13-investigates/floridas-toxic-water-blue-green-algae

[8] EPA, “The Effects: Dead Zones and Harmful Algae Blooms,” supra; EPA, “Health and Ecological Effects,” supra.

[9] R.H. Pierce and M.S. Henry, “Harmful algal toxins of the Florida red tide (Karenia brevis): natural chemical stressors in South Florida coastal ecosystems,” Exotoxicology, Vol. 17, Issue 7, pp. 623-31 (Oct. 2008), https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2683401/

[10] Jenny Staletovich, “Why won’t the red tide go away? After Hurricane Michael, toxic algae has again spread,” Miami Herald, Nov. 6, 2018, https://www.miamiherald.com/news/local/environment/article221148120.html; National Oceanic and Atmospheric Administration, supra (discussing the unusual timing, duration, and size of this year’s HAB).

[11] Karl E. Havens and Hans W. Paerl, “Climate Change at a Crossroad for Control of Harmful Algal Blooms,” Environmental Science & Technology, 2015, 49(21), pp. 12605-12606, https://pubs.acs.org/doi/10.1021/acs.est.5b03990; Angela Fritz, “How climate change is making ‘red tide’ algal blooms even worse,” The Washington Post, Aug. 15, 2018, https://www.washingtonpost.com/news/capital-weather-gang/wp/2018/08/14/how-climate-change-is-making-red-tide-algal-blooms-even-worse/?utm_term=.de3b59072340.

[12] Staletovich, supra.

[13] Achenbach, Furby, and Horton, supra.; see also Andrea Perdoma, “Researcher says Test Results Identify Red Tide Cause,” WMFE, Jan. 11, 2019, https://www.wmfe.org/researcher-says-test-results-identify-red-tide-cause/95825?fbclid=IwAR3J3KOjox0QGdwg-cw4qWAirfKcqC65rtf2A7-DDDVhrZm4NBtgTdFSlnk

[14] T.W. Shaddox and J.B. Unruh, “Florida Fertilizer Usage Statistics,” University of Florida Department of Environmental Horticulture, UF/IFAS Extension, April 2017, https://edis.ifas.ufl.edu/ep541; David Dorsey, “Following the Fertilizer Leads to Farms, Golf Courses, Landscaping Amid Algae Blooms,” Naples Daily News, Sept. 21, 2018, https://www.naplesnews.com/story/news/environment/2018/09/21/florida-algae-crisis-following-fertilizer-leads-farms-golf-courses-landscaping/1377916002/; EPA, “Estimated Animal Agriculture Nitrogen and Phosphorus from Manure,” https://www.epa.gov/nutrient-policy-data/estimated-animal-agriculture-nitrogen-and-phosphorus-manure (last accessed Feb. 17, 2019).

[15] Craig Pittman, “Leaky Septic Tanks Fuel Algae Blooms. Rick Scott OK’d Repeal of Law Aimed to Prevent That,” Tampa Bay Times, July 18, 2018, https://www.tampabay.com/news/environment/Leaky-septic-tanks-fuel-algae-blooms-Rick-Scott-OK-d-repeal-of-law-aimed-to-prevent-that_170059040

[16] Havens, “What is causing Florida’s Algae Crisis?” supra.; see also Tyler Treadway, “Will El Nino or hurricanes bring Lake Okeechobee discharges and algae blooms in 2019?” TCPalm, Dec. 20, 2018, https://www.tcpalm.com/story/news/local/indian-river-lagoon/health/2018/12/20/lake-okeechobee-discharges-algae-blooms-2019/2294367002/

[17] Havens, “What is causing Florida’s Algae Crisis?” supra.; Havens and Paerl, “Climate Change at a Crossroad,” supra.

[18] EPA, “Control and Treatment,” https://www.epa.gov/nutrient-policy-data/control-and-treatment (last accessed Feb. 10, 2019).

[19] Havens, “What is causing Florida’s Algae Crisis?” supra.; see also https://evergladesrestoration.gov/ (last accessed Feb. 10, 2019).

[20] Havens, “What is causing Florida’s Algae Crisis?” supra.

[21] Wei-Haas, supra.; see also Hayley Rutger, “Mote Launches Red Tide Institute for Mitigation and Control, Thanks to Founding Donor,” Mote Marine Laboratory & Aquarium: News & Press, Oct. 23, 2018, https://mote.org/news/article/mote-launches-red-tide-institute-for-mitigation-and-control-thanks-to-found

[22] Achenbach, Furby, and Horton, supra.

[23] Achenbach, Furby, and Horton, supra.

[24] Brady Dennis and Lori Rozsa, “A slimy environmental crisis roils Florida’s tight Senate race,” The Washington Post, Aug. 9, 2018, https://www.washingtonpost.com/energy-environment/2018/08/09/florida-an-environmental-crisis-takes-center-stage-tight-senate-race/?utm_term=.4a061aa5cdb4

[25] Dennis and Rozsa, supra.; see also Lucia Geng, “Yes, Rick Scott did cut $700 million from Florida’s water management districts,” Politifact Florida, Aug. 14, 2018, https://www.politifact.com/florida/statements/2018/aug/14/florida-democratic-party/yes-rick-scott-did-cut-700-million-floridas-water-/

[26] Jenny Staletovich, “As bouts with killer algae rose, Florida gutted its water quality monitoring network,” Miami Herald, August 6, 2018, https://www.miamiherald.com/news/local/environment/article215993665.html

[27] Richard Luscombe, “Rick Scott’s climate record condemned as Hurricane Michael bears down on Florida,” The Guardian, Oct. 9, 2018, https://www.theguardian.com/us-news/2018/oct/09/hurricane-michael-rick-scott-climate-record-slammed; Tristram Korten, “In Florida, officials ban term ‘climate change,’” Miami Herald, March 8, 2015, https://www.miamiherald.com/news/state/florida/article12983720.html.

[28] Pittman, supra.

[29] Jenny Staletovich, “DeSantis calls for South Florida water managers to resign and pulls Scott appointments,” Miami Herald, Jan. 10, 2019, https://www.miamiherald.com/news/local/environment/article224239310.html

[30] Governor’s Office News Release, “Governor Ron DeSantis Announces Major Water Policy Reforms,” January 10, 2019, https://www.flgov.com/2019/01/10/governor-ron-desantis-announces-major-water-policy-reforms/

[31] Ron Brackett, “Florida Governor Details $2.5 Billion Plans to Help Everglades and Fight Algae Blooms,” The Weather Channel, Jan. 10, 2019, https://weather.com/news/news/2019-01-10-florida-governor-everglades-algae-blooms; Jenny Staletovich, “DeSantis announces sweeping fixes meant to clean up Florida water woes,” Miami Herald, Jan. 10, 2019, https://www.miamiherald.com/news/local/environment/article224219365.html#storylink=readmore_inline.

[32] Brackett, supra.; see also Samantha J. Gross, “Does Gov. DeSantis believe in climate change?” Tampa Bay Times, Jan. 11, 2019, https://www.tampabay.com/florida-politics/buzz/2019/01/11/does-gov-desantis-believe-in-climate-change/


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