The latest red tide outbreak on Florida’s Gulf Coast, with its awful stench, is in its 11th straight month. The noxious bloom started in November 2017, and the latest reports from the Florida Fish and Wildlife Conservation Commission before Hurricane Michael, whose effects we won’t know for some time, showed that the end was not near. Conditions change daily, even hourly. For example, the map below shows decreased red tide levels for Septemper 21–28 in Collier County. However, the morning of September 28 found levels increasing in some areas of the county.

If you live or are vacationing on affected areas of Florida’s Gulf Coast, 11 months of toxic, noxious, fish and wildlife-killing red tide is a really long time. But it’s a short period compared to longer blooms, like the 17-monther from 2004 to 2006, or the 21-month bloom just a few years prior to that.

Regardless of bloom duration, one thing is clear: nobody likes red tide. But is there anything people can do about it?

Well, yes and no. I’ve studied harmful algal blooms, or HAB’s, since the 1990s. Back then, I studied a Texas HAB called brown tide. In my master’s thesis, I predicted a large flushing event from a flood or tropical system would break the brown tide’s cycle and allow the system (Copano Bay) to return to normal. And that’s what happened.

Almost always, HABs result from a complex mixture of environmental factors. And compared to Copano Bay’s brown tide in the early 90’s, Florida’s red tide is orders of magnitude more complex. We can manage for some of these factors. Others we can only pray for. And if we start looking at HABs as an opportunity to bring God glory instead of another reason to rant on Facebook or whine about political stuff, maybe we will see these things change. If we let them, real environmental problems like HABs show us how we need to rely on Him, while also doing our part.

What we can’t change

Iron-rich dust from the Saharan Desert is a key ingredient for Florida’s red tide. But it doesn’t help the red tide algae, Karenia brevis. It helps Trichodesmium, a blue-green algae, or cyanobacteria. That’s only the beginning of this complex process. Nitrogen gas, the most abundant element in the atmosphere, is inaccessible to most algal species. Algae like Karenia can only use nitrogen when it exists in compounds like nitrate. So, the Saharan dust is carried across the Atlantic Ocean by tropical weather systems and trade winds, the dominant weather pattern of late summer and early fall. The iron-rich dust settles on the Gulf of Mexico and mixes, where Trichodesmium use it as a key ingredient in a nitrogenase enzyme that converts nitrogen gas to nitrate. When these cells break apart, they release nitrate, which the Karenia then use.

But wait, it gets more complex! Trichodesmium and Karenia live at depth. Those wind patterns described earlier tend to blow surface waters away from Florida’s Gulf Coast, offshore. This causes a process called upwelling, where waters at depth move in to replace surface waters. The pulse of iron that triggered the Trichodesmium bloom that then triggered the red tide bloom moves towards coastal waters. Here, filter-feeding fishes like menhaden dine on the microscopic red tide cells. Fooled into thinking they have hit the jackpot, they are instead overcome by the red tide’s toxins and die. As they decompose, the nutrients they release start feeding the red tide. The red tide no longer needs Trichodesmium, and the bloom continues.

We can’t control the iron-rich Saharan dust or the winds, but there is a third factor as well. Unlike most places on Earth, South Florida is naturally rich in phosphorous. Together with nitrogen, phosphorous is a key nutrient for both algae and plants. Florida has so much phosphorous, in fact, that Central Florida mines produce 65% of U.S. phosphorous. When it rains, phosphorous naturally leaches from the soil and makes its way into Florida’s coastal waters. Nitrogen and phosphorous compounds are also found in fertilizer and sewage. But, red tides were recorded by Spanish explorers hundreds of years ago, before there was much human impact in South Florida. Red tides might be enhanced by human activities, but they certainly aren’t foreign to them, either.

What we can change

The current scientific consensus is that Florida’s red tide is not influenced by human inputs of key nutrients like nitrogen and phosphorous. But really, “scientific consensus” should be considered an oxymoron, especially since scientists are very well known for changing their minds. For example, a well-written 2006 paper mentions human inputs of nutrients trigger the red tide in Texas, but not Florida. Twelve years later though, it appears the same consensus is holding on, even after this year’s record rains sent fertilizer and sewage-loaded waters into Lake Okeechobee and then out the Caloosahatchee River. Massive freshwater algae blooms ensued as these waters made their way to the coast, where the red tide bloom is standing firm.

At a summer Venice, FL, city council meeting, Dr. Michael Crosby of Mote Marine Laboratory and Aquarium in Sarasota stated the current red tide bloom was not initiated by waters coming from Lake Okeechobee. But, we already covered how red tide is initiated in Florida (via Trichodesmium). Dr. Crosby did say red tide levels are correlated with riverine and creek input from the region, and not just a single source like the Caloosahatchee River. While neither Dr. Crosby nor his Mote Lab colleague Dr. Pierce connected human inputs of excess nutrients with sustaining red tide, they did say this:

“Excess nutrients are BAD for freshwater and marine ecosystems, and they should be reduced, whether their sources are from a lake outflow, riverine input, stormwater runoff from the land, or through other means. Excess nutrients need to be dealt with, whatever their source.”

From my experience with aquatic ecosystems, this is sound advice. Just as excess food consumption is bad for you, excess nutrients are bad for waterways. Think of excess nutrients as trash, something you don’t want, but that needs proper disposal.

At this point, it might be good to consider some ancient wisdom from the apostle Paul, whose Letter to the Philippians admonished them to not only look out for their own interests, but also for the interests of others. We are all going to generate trash on a daily basis, but there are things we can do to ensure proper disposal and reduce the amount generated. Let’s consider a few.

At the Venice city council meeting, Dr. Crosby mentioned how it is human nature to desire a simple solution. But it is also human nature to seek out a simple cause to our problems. It’s easier to blame one thing than many things. I read a lot about #BigSugar being responsible for most of South Florida’s water woes. But nutrient runoff from sugar farms is just one of many sources. There are sugar companies that appear interested in being part of the solution, and others, including the state of Florida, that appear at times to be part of the problem. Regardless of who it is, all farmers and agribusinesses should be doing everything they can to keep their soil and their fertilizer and other materials on their land—where, after all, it benefits them!—and not let it be washed into the sea to become someone else’s problem.

An important fact about freshwater systems and bays is that they typically have one of two environmental states: (1) clearer water dominated by aquatic plants, or (2) murkier water dominated by microscopic algae. This is because something is going to dominate the nutrient consumption, either plants attached to the surface or bottom, or microscopic algae that shade the water and consume the nutrients, leaving little light or food for the plants. In Florida, lake managers understood this back in the 1980s when Lake Okeechobee suffered from an algae bloom. At the time (as is the case today), herbicides were used to kill a nuisance floating plant known as water hyacinth. Introduced over 100 years ago, water hyacinth has been a constant management problem in Florida’s waterways.

Out-of-control water hyacinth on the Caloosahatchee River, 1939. In the 21st Century, perhaps this longtime nuisance could turn into a beneficial plant, both for excess nutrient management and biofuel production.

For a short period in 1986, spraying of water hyacinth was suspended in hopes that the hyacinth would absorb the excess nutrients coming into the lake, thereby starving the algae. Apparently, it worked, but at the expense of laborious mechanical harvesting of water hyacinth. The hyacinth grew so fast on the excess nutrients that mechanical harvesters could not keep up with it. In the end, they had to use herbicides to kill 11,000 acres of hyacinth and restore navigation.

Today, water hyacinth is under “maintenance control,” meaning when outbreaks occur, they are sprayed before they get too big. Or at least that’s the plan. But, what if it is time to revisit the idea of using water hyacinth as a means of nutrient control? Mechanical harvesting is laborious, but if it reduces nutrients, and if the harvested material can be used for something, like biofuels, then this could be an effective mitigation technique.

At the Venice City Council Meeting, the greatest applause was heard when a city council member mandated landscaping regulations that would restrict levels of watering and fertilizer use. Another council member encouraged residents to contact their lawn service and tell them they don’t want their lawns fertilized, and to use landscaping plants and methods that require less fertilizer and water.

Real Problems Require Real Solutions

If you don’t live or vacation in a place like Venice, Florida, it may be hard for you to believe that using less fertilizer on your yard would be a good idea. After all, your yard must be greener than your neighbor’s yard, right? If that kind of one-upmanship is part of your normal thought process, then you have probably never inhaled the throat and lung-irritating brevetoxins produced by red tide. And you’ve probably never had thousands of dead fish to see and smell on your daily commute for days, weeks, even months at a time.

When there is a real crisis, people are more likely to respond in real ways. Social justice warriors are minimized, and people seeking real solutions are maximized. The citizens of Florida know excess nutrients are a problem. Reducing nutrient levels is something everyone can be actively involved in.

David Shormann, Ph.D., a Marine Chemist and Limnologist and President of DIVE (Digital Interactive Video Education), Houston, TX, is a Contributing Writer for  The Cornwall Alliance.