Toxic Waters | Changing Seas

They are always out there At any one time, if you take a drop of water from anywhere in the oceans, you’ll literally see hundreds of different species But sometimes, algae grow out of control What we’re really concerned about is the frequency and the duration and the intensity of these blooms Harmful algal blooms have dominated the headlines What used to be isolated blooms are now becoming very, very common and widespread And they are affecting the ecosystem I think even just looking at our historic numbers we saw higher numbers in our area of strandings this past year with both sea turtles and marine mammals But how are they impacting human health? You can end up in the hospital for weeks And will they ever go away? One thing we do know is we seem to be seeing bigger and longer-lasting blooms Major funding for this program was provided by the Bachelor Foundation, encouraging people to preserve and protect America’s underwater resources, and by the William J. & Tina Rosenberg Foundation, the Do Unto Others Trust, and by the following (tense music) Algae are aquatic plant-like organisms that include a broad range of species from microscopic phytoplankton to large seaweeds They are the energy producers of the sea At these low levels, they’re a food source for other organisms It’s just at the high levels, where we get blooms, where they become, if you will, killers When algae grow out of control, they can cause harmful algal blooms So, harmful algal blooms are just occurrences of algae that have some kind of negative repercussion either to the environment or to humans, either human health, economy, tourism, things like that Harmful algal blooms have been reported in Florida since the time of the Spanish Conquistadors What is changing now, these things occur naturally, these are algae that have existed in the oceans long before we even had societies as humans They’re starting to grow more frequently into these harmful algal blooms and spreading out where we see them in our waters So, what used to be isolated blooms are now becoming very, very common and widespread So, this is a problem Florida Atlantic University’s Dr. Brian Lapointe is an algae specialist interested in how nutrient pollution affects algal blooms To figure it out, he samples the macroalgae sargassum from his lab in the Florida Keys We have many, many species, but Sargassum natans and Sargassum fluitans are the only species that have adapted to this floating life on the ocean surface A common sight in the tropical and subtropical ocean, sargassum mats are important for the ecosystem Sargassum in its natural state is a very positive thing Sargassum that is floating on the ocean surface supports a diverse array of invertebrates and fishes that are associated with it Some of these are endemic, in fact, they don’t grow anywhere else But like any algae, sargassum can grow out of control, causing a harmful algal bloom What we’ve seen happen, just since 2011, is what I call too much of a good thing These dramatic increases in sargassum growth are thought to be caused by increases in nutrients in the water We have some major river discharges, all carrying increasing nutrients to the coastal ocean, where they become available to sargassum But other factors as well, such as atmospheric deposition, rainfall carrying increasing amounts of nitrate, for example, can be playing another major role

in delivering more nitrogen to sargassum And while sargassum is not a toxic marine algae, coastal communities feel the negative impacts The infrastructure to deal with these excessive amounts of sargassum is just not there We’ve never had to deal with this before I hear from resorts around the Caribbean that are literally ready to shut down They are powerless to do anything to deal with this problem They’ve tried a variety of things, they tried to haul it off the beach, and that might work on certain days when the wind is low, and the currents aren’t strong But ultimately, forces of nature overcome One theory is that a sargassum bloom might trigger other kinds of algal blooms As the sargassum decomposes, it releases chemical compounds, including nutrients that can become problematic Logically, anything that’s gonna fertilize the oceans and give a release of nutrients is a problem (dramatic music) As part of his research, Dr. Malcolm McFarland regularly takes water samples from Florida’s Indian River Lagoon So, this is a device that takes a measurement that is very similar to what a satellite might see orbiting the Earth It basically measures the color of the light that is reflected from the surface of the water back upwards We generally sample once a week or every other week, it depends on what time of year it is We like to keep tabs on what’s going on out there These are basically plants, so they require fertilizer, just like land plants do A lot of those nutrients come from agricultural runoff or sewage treatment plants, people’s septic systems All these sources are increasing the amount of nutrient pollution that is entering the lagoon and other coastal waters One species Dr. McFarland monitors for creates what is known as brown tide The brown tide refers to a species called Aureoumbra lagunensis, and this is especially abundant in the very northern parts of the Indian River Lagoon, near Cape Canaveral Brown tide makes the water look like chocolate milk The water turns brown, dark, dark brown So, at nighttime, they’re actually using oxygen just like we do, for respiration They can draw down the oxygen in the water, and they can cause a fish kill So, all the other organisms that are in the water that need oxygen suddenly can’t breathe, essentially It’s an unusual species that a number of years ago was associated with deep, open ocean environments, but it has found a niche within these coastal lagoons here in Florida, and also over in Texas It is a very small cell So, it’s only a little bit bigger than most bacteria, but it gets incredibly abundant As far as we know, it is not toxic It has not been terribly well-studied as some of the other organisms, like the red tide Red tide is another harmful algal bloom, one that does produce toxins Severe red tide outbreaks have made headlines as fish, some as large as whale sharks, as well as sick or dead sea turtles and marine mammals, have washed up onshore Red tide generally refers to a bloom of a species called Karenia brevis It’s a type of dinoflagellate, which is a type of phytoplankton that is common throughout the world’s oceans And generally, when it gets very abundant, it can discolor the water red, hence the name red tide It’s a really interesting creature It has animal-like characteristics and it has plant-like characteristics The animal-like characteristics is that it has a couple flagella, and it can actually swim up to the surface The plant-like characteristics are that it photosynthesizes So, it’s in one of these unique categories that have a little mix of both Karenia brevis is particularly bad, um it produces a toxin called brevetoxin That’s where the Brevis name comes from It is a neurotoxin Red tides are a regular occurrence off the Florida coast Florida gets them pretty close to annually Now people will kinda scratch their heads at that and say, oh, I remember such and such a year there, we didn’t have any dead fish on the beach

Sometimes the way the physical oceanography works, there’s a red tide perhaps sitting 10 miles offshore, but the currents are such that they don’t get pushed onshore In 2017, there was a severe red tide outbreak off the west coast of Florida The extensive bloom lasted nearly a year and a half, even making its way to the east coast of Florida for a few months, which is a rare occurrence It got advected over, most likely through the Florida Current and up through the Gulf Stream, up into the east coast area of Florida We hope that is not a harbinger of what may happen in the future, that the blooms on the west coast are getting bigger and more persistent, and because of that, their chances of getting moved over to the east coast are now gonna go up And if the east coast may start seeing these same kind of effects year after year During that same outbreak, Dr. Monica Lara conducted regular reef monitoring with her students on the rocky reefs off the west coast of Florida About a couple of weeks after we believe the red tide came through on some of those reefs, we did go out and dive, and it was a dramatic difference There were very few fish, the invertebrates were still there, but there were some bivalves that were dead all over the place One of the theories, and that’s all it is, is a theory, is that red tide released the toxin, the toxin gets in the water, goes across the gill slits of fish Again, it’s a neurotoxin, so it affects the central nervous system, and the fish quit breathing Kills the fish The reef was silent It’s like the sounds from the animals were completely gone So, it was like desert, a silent desert It was really, really dramatic Once the dead fish begin to wash up on shore during a red tide event, many birds start to feed on them Early signs of a red tide in and the seabirds is kind of staggering, drunk behavior, or they won’t be able to stand or walk Kind of be placed on the ground, just sitting there It really affects their neurological system, so they just are kind of hopeless until somebody picks them up or they die Rescue groups say seabirds of all sizes were affected by the red tide outbreak We actually see the smaller birds, like the ruddy turnstones and the sanderlings, first They are kind of our canary in the coalmine We’ll see them immediately, and then we start getting the bigger species, like the laughing gulls and the double-crested cormorants Seabirds are impacted not only from eating poisoned fish, but also from swimming through bloom-filled waters and inhaling the brevetoxin With fluid therapy, the stronger birds are able to expel the toxins and recover We release about 3/4 of the sick birds, which for being such a bad red tide was really good During this severe bloom, rescue missions were also underway at neighboring Mote Marine Laboratory We had extremely elevated numbers of strandings We’ve recovered over 300 sea turtles this year, over 30 dolphins, assisted with countless manatee recoveries and rescues Marine animals are affected by the brevetoxin in different ways So, for our sea turtles, they generally get it through their food, and it’s a neurotoxin. They get really disoriented, they have a hard time surfacing and clearing to get air So, a lot of the carcasses we were recovering had you know indications of drowning If we can get to the animals in time, we can get them help, But, unfortunately, you know, there aren’t people out there to see them Similarly, for the manatees, it’s also a neurotoxin They get that through their airways when they’re breathing And much like the turtles, if we can get to them in time, they can come out of it We’ve had animals that we’re holding their head because they won’t even surface to breathe As we hold their head and they’re breathing a little bit fresher air that’s not right at the air-water interface, they can come out of it And they can metabolize that toxin and actually like leave while we’re waiting for the rescue trucks to get there So, it’s, um, that’s, those are always sort of interesting cases And for the dolphins, we don’t have a great handle We know they get it through their food, but we haven’t had any live dolphins to respond to We know it kills them, because we’ve recovered many carcasses, and most of the animals that we’ve tested from the summer had been positive for brevetoxin at high levels So, we know that’s acute cause of stranding But I don’t know how it affects them when they’re alive Humans are also vulnerable to red tide, since it can aerosolize, and its toxic particles can be breathed in A certain subgroup of humans are very susceptible to breathing the airborne toxins, and in particular, asthmatics need to be very careful

when there’s a red tide in town to not be exposed to the toxins The good news is, everybody reacts to the toxin, and when you inhale it, you get a dry cough, you get nasal congestion, you get eye tearing And why I say that’s good is that you know you’re getting exposed It’s not like something like radon, that you have no knowledge of So, the important message is, don’t avoid the beach, but know what beaches are impacted and what beaches are okay Brevetoxin likely becomes airborne through wave action Humans can also get sick from consuming fish or other seafood that have been exposed to red tide Fish consume the toxin, and the toxin accumulates in the guts of the fish So, if we fish during a red tide, and you filet it, you won’t get sick from any potential toxin, because the toxin’s in the guts of the fish We do need to educate people, there are some cultures who consume whole fish soup And so, they need to know that during red tides, you can’t throw the whole fish in there Your family potentially can get sick The causes of red tide blooms still aren’t clear, although it is thought that there has to be a perfect mix of temperature, oceanic conditions, and nutrients During certain years, the conditions seemed right, that there’s some kind of a nutrient that is added to the system And so, then they’re able to increase in numbers What that nutrient is, we’re not sure Whatever that nutrient is, some experts say humans likely introduced it into the oceans Average abundance of red tide on the west coast now is about 15 times more than it was 50 years ago To generate 15 times more red tide, you need 15 times more nutrients, and I can’t think of any natural sources of nutrients that have increased 15-fold But of course what has increased dramatically here in South Florida over the last 50 years is number of people, agricultural interests, and so on We’re just driving along the northern side of the Caloosahatchee River sampling in various locations along there, right, we just finished sampling the Ortona Lock It’s one of three damns and locks on the Caloosahatchee River And now we’re heading over to the west coast Red tide isn’t the only algal bloom that’s been wreaking serious havoc in Florida waterways in recent years Dr. Larry Brand has been sampling for cyanobacteria in the waters around Lake Okeechobee and in the Caloosahatchee River for almost 20 years Well there’s a lot of changes I can’t really say for sure there’s been a longterm change over the past 20 years, but certainly, some years you have really bad blooms of cyanobacteria, and some years you have less so But it’s very clear that these are very nutrient-rich waters, and you often do get these large blooms of cyanobacteria When water levels in Florida’s Lake Okeechobee get too high, flood managers, fearing a breach in the dike surrounding the lake, discharge billions of gallons of water through canals, rivers, and streams into the Gulf of Mexico and the Atlantic Ocean This can bring nutrients which have built up in Lake Okeechobee to the estuaries, causing these algal blooms The cyanobacteria tend to do better in warmer weather, so we tend to get these blooms primarily in the summertime ‘Course it’s also in the summertime because that’s when you have more rainfall here in South Florida, that’s the wet season, so you get a lot more land runoff, and of course that’s the source of most of the nutrients in Lake Okeechobee and the Caloosahatchee River Various nutrient sources on land, and then during the wet season, all that rain water flushing those nutrients into the water bodies Cyanobacteria are also known as blue-green algae They were some of the first organisms on Earth They’re really tough, it’s really hard to kill ’em And we now know they produce a lot of pretty nasty toxins They also produce over 1,000 other compounds which simply have not been characterized yet, we have no idea what the health hazards may be when you’re exposed to these blooms But some of the best known ones are for microcystin That can lead to longterm liver damage and even liver cancer, and more recently we’ve discovered a compound called BMAA, and there’s increasing evidence, pretty good evidence now, that it can lead to neurodegenerative diseases like Alzheimer’s, Parkinson’s, and ALS Blooms of cyanobacteria are characteristically bright green, and can be as thick as guacamole Every time I travel along the Caloosahatchee River here

or along the shores of Lake Okeechobee, I see people fishing I know there’s high concentrations of BMAA in these fish and probably also microcystin I certainly would not eat the fish in this river But I do see people doing so And there’s no signs along any of these water bodies warning people about the presence of these toxins Experts say the biggest question now is whether cyanobacteria pose an even bigger, more silent threat than we know Well right now what we’re focusing on is the possibility of the toxins in these blooms of cyanobacteria getting into the air Now for the red tide offshore, it’s been known for a long time that that toxin gets into the air, ’cause it has immediate effects on people’s eyes, nose, throat I call that a good toxin in that you know right away you’re being exposed to it, so you can do something about it But these toxins here in these blooms of cyanobacteria, like microcystin and BMAA, microcystin can have short-term effects, but the BMAA has no short-term effects, it only has longterm effects If that toxin is getting into the air, if you live near this river or some of these other water bodies that get frequent blooms of cyanobacteria, you could be breathing in this BMAA, not know it, and then 10 or 20 years from now you could come down with Alzheimer’s So it’s a much more insidious toxin To determine if cyanobacteria can become airborne, a multidisciplinary team at the University of Miami is working with Dr Brand’s water samples The team designed a wave tank to create conditions like those at Lake Okeechobee We have a wind wave tank set up in order to blow air and create more realistic conditions for the transfer of the aerosols across the air-sea interface So we’re gonna create this condition where the wind’s blowing over the water surface and see what’s produced My lab does realtime techniques to measure the size as well as the composition of these particles, but if we wanna quantify their toxins, what we do is we collect the particles on a filter, and then Dr. Popendorf’s lab extracts the material off of the filter and uses her mass spectrometer to quantify the toxins and also figure out which toxins are present in the samples So the two techniques are really complementary for understanding the impacts of these particles on human health This project is in its early stages, so the results are still unknown But one researcher from the medical school is already anticipating some interesting results My lab studies neurological diseases, including neurodegenerative diseases, and we use fruit fly as a model After exposing some flies to cyanobacteria from Lake Okeechobee blown through a bubbler for an hour, Dr. Grace Zhai noticed some differences in the flies’ behavior So, there’re several behavior tests to look at their nervous system function, and so, first one and most commonly used one is called a climbing behavior So what you can see actually is normally flies would climb up if I flip this, all the flies started to climb upwards This is the first time we’re running this experiment So, we can already see an immediate difference between these two groups So this one hasn’t been exposed This one has been exposed to the aerosolized particle for one hour So can you tell which one is faster? Not all toxins found in nature are necessarily bad One of Dr. John Berry’s missions is to identify new compounds in harmful algal blooms that may actually be beneficial to humans In one experiment, he tests toxins he extracted from cyanobacteria on cancer cells We pulled out compounds that people just, they’re not on the radar yet, and that’s the idea, is to get some of these new potential toxins on the radar so that we can start to understand if they’re having an effect They’ve been a real goldmine for people looking for biologically active natural products for drug leads, so, they’re sort of these toxin slash drug producing little factories out there in nature Florida has been hit hard with multiple algal blooms negatively impacting the environment, human health, and the economy The length and severity of these blooms is getting worse People living along Florida’s biggest waterways are clamoring for help in putting an end to the blooms There are a number of people who are starting to hypothesize that we’ve hit a tipping point, that the combination of climate change and the patterns of rainfall and warmer waters

that we’ve gone through, combined with all the development and land use practices that we’re doing around our coastlines and the nutrient pollution that we’re putting into our waterways has put the systems into a very bad position, that they’re irrevocably harmed, that we’re not gonna get them back I don’t fundamentally believe that, I do believe if we can get a control on nutrient pollution nature will fix itself Nature is very resilient, it just needs time to recover If we keep on beating it and polluting it, it’s never going to recover, and yes, we’ll be living with this forever Major funding for this program was provided by the Batchelor Foundation, encouraging people to preserve and protect America’s underwater resources, and by the William J. & Tina Rosenberg Foundation, the Do Unto Others Trust, and by the following