The best of EcoWatch, right in your inbox. Sign up for our email newsletter!
What Is Causing Florida’s Algae Crisis? 5 Questions Answered
By Karl Havens
Editor's note: Two large-scale algae outbreaks in Florida are killing fish and threatening public health. Along the southwest coast, one of the longest-lasting red tide outbreaks in the state's history is affecting more than 100 miles of beaches. Meanwhile, discharges of polluted fresh water from Lake Okeechobee and polluted local runoff water from the St. Lucie and Caloosahatchee watersheds have caused blooms of blue-green algae in downstream estuaries on both coasts. Karl Havens, a professor at the University of Florida and director of the Florida Sea Grant Program, explains what's driving this two-pronged disaster.
What's the difference between red tide and blue-green algae?
Both are photosynthetic microscopic organisms that live in water. Blue-green algae are properly called cyanobacteria. Some species of cyanobacteria occur in the ocean, but blooms—extremely high levels that create green surface scums of algae—happen mainly in lakes and rivers, where salinity is low.
Red tides are caused by a type of algae called a dinoflagellate, which also is ubiquitous in lakes, rivers, estuaries and the oceans. But the particular species that causes red tide blooms, which can literally make water look blood red, occur only in saltwater.
What causes these blooms?
Blooms occur where lakes, rivers or near-shore waters have high concentrations of nutrients—in particular, nitrogen and phosphorus. Some lakes and rivers have naturally high nutrient concentrations. However, in Lake Okeechobee and the St. Lucie and Caloosahatchee estuaries, man-made nutrient pollution from their watersheds is causing the blooms. Very high levels of nitrogen and phosphorus are washing into the water from agricultural lands, leaky septic systems and fertilizer runoff.
Red tides form offshore, and it is not clear whether or to what extent they have become more frequent. When ocean currents carry a red tide to the shore it can intensify, especially where there are abundant nutrients to fuel algae growth. This year, after heavy spring rains and because of discharges of water from Lake Okeechobee, river runoff in southwest Florida brought a large amount of nutrients into near-shore waters of the Gulf of Mexico, which fueled the large red tide.
Algae is clearly visible in this satellite image of southwestern Lake Okeechobee, taken July 15.NASA Earth Observatory
The public health advisories about red tide are related to respiratory irritation, which is a particular concern for people with asthma or other respiratory issues. But almost anyone, including me, who has walked a beach where there is a red tide will quickly experience watering eyes, a runny nose and a scratchy throat. The algae that cause the red tide release a toxic chemical into the water that is easily transported into the air where waves break on the shore.
Some people are allergic to cyanobacteria blooms and can have contact dermatitis (skin rash) on exposure. Several of my colleagues have developed rashes after submerging their hands to collect water samples. It is not advisable to purposely contact water with a cyanobacteria bloom. And if farm animals or pets drink water with an intense bloom, they can become seriously ill or die.
Above video: The blooms are causing widespread fish kills and threatening Florida's tourism industry.
How can states prepare for these events?
The onset of algae blooms is unpredictable. We know high levels of nutrients allow a lake or shoreline to have blooms. We even can predict with some certainty that a bloom is likely in a particular summer—for example, if in the preceding spring heavy rainfall and runoff from the land delivered large amounts of nitrogen and phosphorus into the water.
But we can't predict exactly when a bloom will begin and end, because that depends on things we can't project. Why did the cyanobacteria bloom start in Lake Okeechobee this summer? Perhaps because there were several successive hot sunny days with little cloud cover and little wind. For some lakes in Florida and many others across the nation, we have loaded the surrounding land with so much phosphorus and nitrogen from agricultural and urban runoff that all it takes is the right weather to trigger a bloom: A rainy spring and then a few perfect sunny days in summer.
We cannot control the weather, but we can control nutrient pollution, both by reducing it at its sources and by capturing and treating water running off of large land areas. Florida has many such projects under way as part of the greater Everglades restoration efforts, but they will take decades to complete.
Nutrient pollution sources include decaying organic material; fertilizers applied to crops, lawns and golf courses; manure from fields or feedlots; atmospheric deposition; groundwater discharge; and municipal wastewater discharge. USGS
One key aspect of rehabilitating polluted lakes, rivers and estuaries is knowing whether actions are having a positive effect. This requires long-term environmental monitoring programs, which unfortunately
have been scaled back in Florida and many other states due to budget cuts.
Carefully designed monitoring could help us understand factors affecting the kind of blooms that occur and what triggers them to start and stop at particular times, and provide guidance on nutrient control strategies. We are not monitoring at that level now in Florida.
Is climate change influencing the size or frequency of these outbreaks?
Scientists have clearly shown that there is a positive and synergistic relationship between water temperature, nutrients and algal blooms. In a warmer future, with the same level of nutrient pollution, blooms will become harder if not impossible to control. This means that it is urgent to control nutrient inputs to lakes, rivers and estuaries now.
Unfortunately, today the federal government is relaxing environmental regulations in the name of fostering increased development and job creation. But conservation and economic growth are not incompatible. In Florida, a healthy economy depends strongly on a healthy environment, including clean surface waters without these harmful blooms.
Reposted with permission from our media associate The Conversation.
- Across U.S., Toxic Algal Blooms Threaten Lakes and Other Waterways ›
- Nearly 300 Sea Turtles Dead as Red Tide Plagues Southwest Florida ›
EcoWatch Daily Newsletter
Tuna auctions are a tourist spectacle in Tokyo. Outside the city's most famous fish market, long queues of visitors hoping for a glimpse of the action begin to form at 5 a.m. The attraction is so popular that last October the Tsukiji fish market, in operation since 1935, moved out from the city center to the district of Toyosu to cope with the crowds.
gmnicholas / E+ / Getty Images
Kristan Porter grew up in a fishing family in the fishing community of Cutler, Maine, where he says all roads lead to one career path: fishing. (Porter's father was the family's lone exception. He suffered from terrible seasickness, and so became a carpenter.) The 49-year-old, who has been working on boats since he was a kid and fishing on his own since 1991, says that the recent warming of Maine's cool coastal waters has yielded unprecedented lobster landings.
The climate crisis is getting costly. Some of the world's largest companies expect to take over one trillion in losses due to climate change. Insurers are increasingly jittery and the world's largest firm has warned that the cost of premiums may soon be unaffordable for most people. Historic flooding has wiped out farmers in the Midwest.
Hawaii's Kilauea volcano could be gearing up for an eruption after a pond of water was discovered inside its summit crater for the first time in recorded history, according to the AP.
'We Should Be Retreating Already From the Coastline,' Scientist Suggests After Finding Warm Waters Below Greenland
By Johnny Wood
The Ganges is a lifeline for the people of India, spiritually and economically. On its journey from the Himalayas to the Bay of Bengal, it supports fishermen, farmers and an abundance of wildlife.
The river and its tributaries touch the lives of roughly 500 million people. But having flowed for millennia, today it is reaching its capacity for human and industrial waste, while simultaneously being drained for agriculture and municipal use.
Here are some of the challenges the river faces.
By Jake Johnson
As a growing number of states move to pass laws that would criminalize pipeline protests and hit demonstrators with years in prison, an audio recording obtained by The Intercept showed a representative of a powerful oil and gas lobbying group bragging about the industry's success in crafting anti-protest legislation behind closed doors.
Speaking during a conference in Washington, DC in June, Derrick Morgan, senior vice president for federal and regulatory affairs at the American Fuel & Petrochemical Manufacturers (AFPM), touted "model legislation" that states across the nation have passed in recent months.
AFPM represents a number of major fossil fuel giants, including Chevron, Koch Industries and ExxonMobil.
"We've seen a lot of success at the state level, particularly starting with Oklahoma in 2017," said Morgan, citing Dakota Access Pipeline protests as the motivation behind the aggressive lobbying effort. "We're up to nine states that have passed laws that are substantially close to the model policy that you have in your packet."
Big Oil is now using its political power to try and criminalize protests of oil & gas infrastructure.— Friends of the Earth (@foe_us) August 19, 2019
"This legislation has potential to punish public participation and mischaracterize advocacy protected by the First Amendment."https://t.co/bmiHjONEhy
The audio recording comes just months after Texas Gov. Greg Abbott signed into law legislation that would punish anti-pipeline demonstrators with up to 10 years in prison, a move environmentalists condemned as a flagrant attack on free expression.
"Big Oil is hijacking our legislative system," Dallas Goldtooth of the Indigenous Environmental Network said after the Texas Senate passed the bill in May.
As The Intercept's Lee Fang reported Monday, the model legislation Morgan cited in his remarks "has been introduced in various forms in 22 states and passed in ... Texas, Louisiana, Oklahoma, Tennessee, Missouri, Indiana, Iowa, South Dakota, and North Dakota."
"The AFPM lobbyist also boasted that the template legislation has enjoyed bipartisan support," according to Fang. "In Louisiana, Democratic Gov. John Bel Edwards signed the version of the bill there, which is being challenged by the Center for Constitutional Rights. Even in Illinois, Morgan noted, 'We almost got that across the finish line in a very Democratic-dominated legislature.' The bill did not pass as it got pushed aside over time constraints at the end of the legislative session."
Many of the state bills restricting the right to protest have been "drafted by companies and passed through groups like ALEC, the secretive group of corporate lobbyists trying to rewrite state laws to benefit corporations over people." @greenpeaceusa https://t.co/ZxpTjWdrwT— Stand Up To ALEC (@StandUpToALEC) May 6, 2019
Reposted with permission from our media associate Common Dreams.