Red Tide Updates

Red Tide is a menace with no simple solution

The infamous red tide algae on Florida’s southwest coast has died or moved offshore, so beaches are open to visitors again.

Data gathered during the 2018 event is showing why those blooms originate offshore, when they form and their routes to the shoreline. Researchers dispatched and steered a robotic minisubmarine with sensors that picked up the red tide scent way offshore and then tracked it to the coast. Computer simulations with the new data showed that the spring or summer timing of ocean currents make a big difference.

Typically, offshore loop currents and eddies push up against the West Florida continental shelf in the spring. This causes an upwelling which moves nutrients to the surface. In most years, the red tide algae (Karenia brevis) remains offshore on the bottom and, without a supply of nutrients, remains quiescent.

In 2018, however, Gulf loop currents pushed up against the shelf later than usual, in mid-July, but by then K. brevis cells were already gorging on nutrients and blooming. Ocean
currents and winds then brought the algae to the shoreline. A team led by Dr. Robert Weisberg at the College of Marine Science at the University of South Florida in St. Petersburg has published the findings in the Journal of Geophysical Research.

But below the surface, marine life took a big hit. Snook and redfish, two nearshore gamefishes, are of major concern. Recently, new initiatives were announced to help the cause.

One is Adopt a Snook, a collaboration of Coastal Conservation Association-Florida,
Mote Marine and the Florida Fish and Wildlife Conservation Commission (FWC).
The plan is to raise and release 10,000 juvenile snook into brackish tidal creeks in
2019 and 2020.

To protect stocks and to maximize future spawning success, FWC has extended the
catch-and-release calendar for snook and redfish from Pasco County south to Gordon
Pass near Naples. Until May 11th, anglers in that zone must release all snook and
redfish. After May 11th, redfish regulations return to normal and anglers may keep one
redfish between 18 and 27 inches. The regular fall snook season starts September 1st.
Anglers may keep one snook between 28 and 33 inches until the end of November.

Another initiative directly tackles water quality to benefit all marine life. Sarasota
Bay Watch (SBW) is more than doubling down on planting native clams to help filter out
unwanted nutrients that make algae blooms worse. In 2017 and 2018, SBW volunteers
planted close to 250,000 native clams in Sarasota Bay. Those clams survived the 2018
red tide bloom, giving the nonprofit a green light to proceed with a new, long-term
plan to raise funds, enlist volunteers and plant another one million clams to filter out
unwanted nutrients.

What Happened?

So far, a million pounds of decaying marine life have been disposed of, including hundreds of sea turtles, dozens of dolphins, over 100 manatees, and even a whale shark. A noticeable stench was often present, and many beach-goers fell victim to respiratory stress including breathing difficulties and coughing. And we have red tide to blame for it.

Sludgy blue-green algae invades the shores of Martin County.

What is it?

What exactly is red tide? It’s one-celled algae called Karenia brevis commonly found in the Gulf, and typical blooms (rapid increases in numbers) cause little problem. In high concentrations, however, the algae turn the water a reddish-brown color (hence the name). But because this event has nothing to do with tides, scientists prefer to call it a harmful algal bloom (HAB). Similar situations occur in other areas around the world with a variety of algal species. But this particular HAB is especially noted along the Gulf shores of Florida and Texas and can be extremely harmful.

K. brevis emits a toxin called brevetoxin, and excessive blooms can fill coastal waters with it. Shellfish are immune, but they accumulate the brevetoxin in their bodies, which makes them hazardous to eat. Other aquatic life succumb to the poisonous waters. For people, problems arise through skin irritation and rashes after swimming in it or when, according to Kristie Anders, education director of the Sanibel-Captiva Conservation Foundation, “Crashing waves turn the toxin into an aerosol which people breathe in.” Those already with chronic respiratory issues are at particular risk. There may even be long-term health effects.

To put numbers on the problem, background concentrations of K. brevis are 1,000 cells per liter of water or less. At concentrations of 5,000, shellfish, if eaten, can cause illness, and harvesting beds are closed. Fish kills and human respiratory problems can start when concentrations of this algae reach 10,000 (still classified as “Low”). This year, levels surpassed one million (“High”) at the coastline. Concentrations some distance offshore are even worse with readings in the tens of millions.

What do the experts say?

Marc Suddleson, program manager of NOAA’s National Centers for Coastal Ocean Science Monitoring and Event Response for Harmful Algal Blooms Research Program, says that the red tide algal blooms typically start in late July, often 10 to 40 miles off the coast. K. brevis can actually move, primarily with the wind and currents. Patches of the algal bloom then drift toward the shoreline where concentrations increase due to the shallower water’s lower salinity and increased nutrient levels, notes Dr. Robert Weisberg, professor and director of the University of South Florida’s Ocean Circulation Group. Occasionally, the blooms “explode,” and that’s when problems occur.

The current event actually began in October 2017. Anders points out that rainfall from Hurricane Irma in September caused nutrient-rich runoff water to flow into the estuaries and mix with offshore waters enough to stimulate a K. brevis bloom. This moved ashore and intensified and by the end of the year, dead fish were reported in Charlotte, Lee and Sarasota counties. Later in the winter, cooler water temperatures blunted the bloom, but with the warmer temperatures of summer, it came back with a vengeance.

The major questions are: What causes the explosive K. brevis blooms, and what can we do to stop them? It is widely believed that the culprit is nutrient pollution from inland agricultural runoff. There is a major push to do something about this.

What does it mean for today?

From anecdotal evidence, we know that red tide events that produce fish kills have been occurring in the Gulf for hundreds of years, even as far back as the 1700s. With limited data, we have no way to compare those events to today. In any case, Suddleson claims that red tide events now seem to start earlier, last longer, occur more frequently, and are more intense. He also adds that nutrient pollution may be a contributing factor but is not a significant factor. In fact, a long-term research project sponsored by NOAA concluded in 2014 that there is no direct link between nutrient pollution and the initiation of red tide.

So, what is the cause?

Algae are very simple, mainly aquatic plants that need sunlight, nutrients in the water and a proper water temperature and salinity, all of which vary with species. Variance in any of these factors can affect algal growth. Clouds of dust which have traveled across the Atlantic from the Sahara Desert can block some light.

Also, if one species of algae blooms earlier, it can block the sunlight from other, slower developing species. Nutrients in the water come from a variety of sources. Anders points out that large phosphate deposits and mines have existed for years in the area around the Peace River, which empties into Charlotte Harbor located north of Ft. Myers, Florida. She also notes that in this rapidly developing region, there are many sources of nutrient pollution, including lawn fertilizers.

Dr. Weisberg has his own theory on red tide events. He believes the Loop Current, which dominates the circulation of the Gulf, varies in exact location. At times, the circulation produces strong upwelling off Florida’s west coast. If this happens in the spring or summer, these nutrient-rich bottom waters feed other types of algae which can then suppress K. brevis. Red tide events occur when K. brevis outcompetes other algae. Using past data on Loop Current position and red tide events, Dr. Weisberg noted a near perfect correlation, and the model is used to predict future outbreaks. Once an event is ongoing, Weisberg’s group sends out forecasts of movement going out for several days

How will we know what’s going on?

In terms of the water itself, one lab-based study showed that the K. brevis algae had an increased growth rate when both the water temperature and carbon dioxide level in the water increased. We know that both of these are occurring. However, Suddleson points out that there is a limit to this and if water temperatures continue to increase, K. brevis may not fare well.

Red tide is monitored closely. NOAA uses satellite observations to detect K. brevis blooms while they are still far offshore. Water samples along the coast are analyzed for the algae’s presence. When an event has developed, NOAA will issue forecasts twice weekly which include actual conditions and expected impacts. The Florida Fish and Wildlife Conservation Commission sends out a weekly Red Tide Status update which includes a forecast done in conjunction with USF.

Although scientists may disagree about the impact of agricultural runoff for red tide but can agree that red tide causes additional problems. Blue-green algae outbreaks and red tide should be controlled. Red tide is an extremely complex problem still being studied for both its cause and the solution, neither of which offers simple answers.

By Ed Brotak, Southern Boating October 2018

The Dead Zones

“The Dead Zone” may sound like the title to an old horror movie, but these barren ocean wastelands are very real. Officially referred to as “hypoxia”, dead zones are areas of the ocean that are devoid, or nearly devoid, of aquatic life. Creatures that could move away have done so, while others have died. The problem is a reduced level of life-sustaining oxygen in the water. Some dead zones occur naturally. However, the worst of them today are the result of man’s activities.

The main cause of man-made dead zones is nutrient pollution called “eutrophication” by scientists. Nutrients such as nitrogen and phosphorous are vital to plants and are major ingredients in many fertilizers. If excessive amounts of these elements find their way into bodies of water—fresh or salt water—they will spur the overgrowth of algae and phytoplankton (microalgae). The initial algal bloom can block sunlight from reaching the
waters below. Plant life at lower levels can’t produce oxygen thus beginning the hypoxia process. When the algae die and sink it will decompose, using up more oxygen in the lower reaches. There is not enough oxygen left to support normal aquatic life and the result is a dead zone.

Eutrophication has steadily increased in recent years due to industrial activities, the effluent from wastewater treatment and, in particular, intensive agricultural practices. It is estimated that human activities produce twice as much nitrogen and phosphorous as natural sources. The extensive use of animal manure and commercial fertilizers to
increase agricultural production is a major source of nutrient contamination in water that has drained off farmlands.

Dead zones typically develop during the summer months. Obviously, during the growing
season, more fertilizer, etc. is being applied to crops. Also, we get temperature stratification in bodies of water. Upper layers are heated by the intense sunlight. The
warmer water is less dense, lighter and there is little vertical mixing with the colder, denser water below. If decomposing algae uses up oxygen in the bottom waters, it can’t be replenished from above. Dead zones normally last several months until fall weather systems promote mixing.

It’s important to note that although dead zones and the red tide can be linked to a similar cause—nutrient pollution— they are not the same. The red tide is also an excessive algae
bloom, but in this case, an actual toxin is released into the water by the algae. This can kill fish, make shellfish dangerous to eat and even make people sick.

Dead zones exist around the world; more than 100 of them have been documented. In the U.S. alone, the Great Lakes, the East Coast and, particularly, the Gulf of Mexico all have dead zones. The northern Gulf, the region of the Louisiana/ Texas continental shelf, has an enormous dead zone in the summer. This is critical since the northern Gulf encompasses almost half of the nation’s coastal wetlands. Commercial and recreational fishing in the region, including the shrimp industry, generate $3 billion annually.

The Gulf of Mexico Dead Zone was first discovered in August 1972. Scientists found oxygen-depleted bottom waters off the Louisiana coast at depths ranging from 30 to 70 feet. Normally, oxygen levels identify about 7 parts per million (ppm), but they had dropped to 2 ppm or less. It is believed that even though there was some oxygen depletion noted before this, conditions became much worse starting in the 1970s. Since
1985, the dead zone has been measured and mapped to show its size, and the actual size of the dead zone varies from one year to the next. This past summer, the Gulf of Mexico dead zone grew to 8,776 square miles, the size of New Jersey. Not only was this the largest it’s ever been since measurements began, but the Gulf of Mexico now had the largest dead zone in the world.

Why is this occurring here? The Mississippi River flows into the Gulf of Mexico along the Louisiana coast. The Mississippi River watershed encompasses 1.2 million square miles or 41 percent of the continental U.S., and it even extends into Canada. Much of this land is devoted to agriculture.

There is no way to remotely detect dead zones. Satellite imagery can show massive algal and phytoplankton blooms near the ocean surface, which are the precursor of hypoxic areas. But to check what’s going on underneath the surface, samples of water must be taken. One of the main groups dealing with this problem is the Louisiana Universities Marine Consortium (LUMCON). They have a Hypoxia Research Team that monitors conditions in the northern Gulf utilizing a marine laboratory (the DeFelice Marine Center) and a fleet of research vessels.

On the Federal side, the National Centers for Coastal Ocean Science not only provide money for research but also produce an annual forecast in June of the expected maximum size of the Gulf dead zone. Computer models use runoff projections for the Mississippi River based on antecedent precipitation. To help alleviate this problem, the EPA-formed Mississippi River/ Gulf of Mexico Hypoxia Task Force has set a goal size of under 2,000 square miles for the dead zone by 2035. And though some reduction in nutrient pollution
has been accomplished, it is estimated that a further reduction of 60 percent would be necessary to achieve the set goal.

By Ed Brotak, Southern Boating January 2017

Fish Faster with Propspeed

Loosen Up

Keep propellers and underwater gear free of marine growth for top performance.

Marine growth can be a real drag on your boat’s performance. When your vessel is in the water, algae, barnacles, and other sea life look for places to all home, and that includes the propellers and running gear. Bottom cleaning can’t always keep up, and sooner or later the surfaces are overwhelmed with biological growth that compromises your boat’s efficiency. While it may not make a difference in short runs, the miles add up when you’re burning more fuel because the boat is not operating at peak hydrodynamic efficiency. That’s where a product called Propspeed comes in, a foul release coating system that keeps marine growth at bay. “The short story is more speed, less fuel,” explains Mark Billingsley, a technical and sales support specialist for Propspeed, headquartered in Auckland, New Zealand. “We are all about increasing a vessel’s performance. We allow the engine to be under a lot less engine load, burning less fuel and giving you more speed. It’s the most inexpensive repower a boat owner will ever undertake.”

“The short story is more speed, less fuel,” explains Mark Billingsley, a technical and sales support specialist for Propspeed, headquartered in Auckland, New Zealand. “We are all about increasing a vessel’s performance. We allow the engine to be under a lot less engine load, burning less fuel and giving you more speed. It’s the most inexpensive repower a boat owner will ever undertake.”

Propspeed works by lowering the surface tension of the water on the running gear. The Propspeed system is made up of a two-component etching primer, which bonds to the metal substrate, and a clear coat, which gives an ultra-smooth outer layer. The silicon topcoat provides a clear membrane that allows for the expansion and contraction of the metals so that Propspeed doesn’t crack and peel off.

“For decades, the only solution the industry had to reduce marine-growth attachment was to put on multiple coats of a two-part epoxy primer and then over the top of that a non-copper-containing antifouling paint,” Billingsley adds. “However, the expansion and contraction causes fractures in the paint, and water penetrates the coating and it pops off.” Propspeed offers easy maintenance to prevent marine growth from adhering to the substrate. Simply by running the boat, biological organisms are washed off by the water flow. At the dock, a diver’s glove or rag easily wipes off any organisms that try to attach. Keeping marine growth off a vessel’s metal parts is often done with conventional antifouling paint that includes biocides. Some antifouling coatings contain copper, a strong marine contaminant that was recently banned in the state of Washington. When the biocide is exhausted, it loses its effectiveness—that can happen within a few months and re-coating is required.

Propspeed, however, can work up to two years. It doesn’t contain biocides, copper or tin,
and works because it’s slick rather than due to any toxicity. Some caution, however, needs to be taken to ensure Propspeed stays useful. Its soft coating can be damaged by abrasion or mproper maintenance. Shallow areas with rocks and sand may affect the propellers and cause the tips to be scoured, but with good boating conduct there should not be problems. “Propellers with Propspeed will perform six months or a year later the same way as the day Propspeed was applied,” claims Don MacRae, president and COO of Frank & Jimmie’s Propeller shop, based in Fort Lauderdale. “There will be
no loss of speed because of fouling. Propspeed is the most popular coating requested by our customers at Frank & Jimmie’s because it works.” Cruising boats in the 40- to 80-foot range are ideal candidates for Propspeed, and the usual time for application is during haul-out.

“All of our Propspeed application technicians at Frank & Jimmie’s completed [the company’s product] applicator training course so they understand how to properly prepare the propeller surface for a quality application,” MacRae adds. “Additionally, our more advanced technicians have learned how to feather-in small repairs to the Propspeed surface, resulting in quicker turnaround times and less expense for our customers.”

Because more clients are doing their own maintenance and repairs, Propspeed also offers its product in three different volume amounts at outlets such as West Marine. For example, do-it-yourselfers can pick up a Propspeed DIY 500ml kit for $350. It comes with enough Propclean Wipes, Etching Primer and Propspeed Clear Coat to coat two propellers up to 42 inches in diameter. “For a 40-footer with a set of four-bladed 24-inch props, the customer is going to require our 500ml kit,” Billingsley states. “If the customer wants to include the shafts, struts and rudders, then he could bump up to the one-liter kit, which is twice the liquid and costs about $500 for the complete kit.” Owners of smaller boats who want to do their own work, say a 30-footer with twin three-blade 20-inch props, would require only the 200ml kit, which sells for around $250. “In this case, the boat owner wouldn’t have to haul the boat out, just pull the props,” Billingsley advises. “The kits include detailed instructions on how to apply Propspeed, so if the person is comfortable working on their boat, then applying our product will be well within their skills.”

By Don Minikus Southern Boating Magazine June 2016