Thad Johnsons paper
Excellent reserach
Nutrient Dynamics
One of the explanations given for the increased incidence of HAB outbreaks worldwide is that these events are a reflection of increased pollution and nutrient loading in coastal waters. Some argue that we are witnessing a fundamental change in the phytoplankton species composition
of coastal marine ecosystems throughout the world due to the changes in nutrient
supply ratios from human activities [ Smayda, 1990]. There is no doubt that this is true in certain areas of the world where pollution has
increased dramatically. It is perhaps real, but less evident in areas where coastal pollution is more gradual and unobtrusive. A frequently
cited data set from an area where pollution is a significant factor is from Tolo Harbor in
Hong Kong, where population growth within the watershed grew6-fold between 1976
and 1986. During that time, the number of observed red tide events increased 8-fold [ Lam and Ho, 1989]. The underlying mechanism ispresumed to be increased nutrient loading from pollution that accompanied human population growth. A similar pattern emerged from a long-term study of the Inland Sea of Japan, where visible red tides increased steadily from 44 per year
in 1965 to over 300 a decade later, matching the pattern of increased nutrient loading from pollution [ Murakawa, 1987]. Japanese authorities instituted effluent controls in the mid-1970's, resulting in a 50% reduction in
the number of red tides that has persisted to this day.

These two examples have been criticized, since both could be biased by changes in the numbers of observers through time, and both
are tabulations of water discolorations from algal blooms, not just toxic or harmful  episodes. Nevertheless, the data demonstrate that coastal waters receiving industrial, agricultural, and domestic effluents, which
frequently are high in plant nutrients, do in fact experience a general increase in algal
growth. These nutrients can stimulate or enhance the impact of toxic or harmful species in several ways. At the simplest level,toxic
phytoplankton may increase in abundance due to nutrient enrichment but remain as the same
relative fraction of the total phytoplankton biomass (i.e.all phytoplankton species are affected equally by the enrichment).
Alternatively, some contend that there has been a selective stimulation of HAB species by
pollution. This view is based on the nutrient ratio hypothesis [Smayda, 1990] which argues that environmental selection of phytoplankton speciesis associated with the relative availability of specific nutrients in coastal waters, and that human activities have altered these nutrient supply ratios in ways that
favor harmful forms. For example, diatoms, the vast majority of which are harmless, require silicon in their cell walls, whereas most
other phytoplankton do not. Since silicon is not abundant in sewage effluent but nitrogen and phosphorus are, the N:Si or P:Si ratios in
coastal waters have increased through time over the last several decades. Diatom growth in these waters will cease when silicon supplies are depleted, but other phytoplankton classes (which have more toxic species) can continue to proliferate using the ``excess'' nitrogen and phosphorus.

This concept is controversial, but is not without supportingdata. A 23-year time series off the German coast documents the general
enrichment of coastal waters with nitrogen and phosphorus, as well as a four-fold increase in
the N:Si and P:Si ratios [ Radach et al., 1990]. This was accompanied by a striking change in the composition of the phytoplankton community, as diatoms decreased and flagellates increased more than ten-fold.

As coastal communities and countries struggle with pollution and eutrophication issues, the implications of these studies are profound. Increasingly, the possible stimulation of HAB species by domestic or industrial effluent is being raised by those in opposition to public
works projects. One example is a proposed new sewage outfall that will release up
to 1 billion gallons of effluent each day into Massachusetts Bay at a point near the pathway of the coastal current described above for
the PSP dinoflagellate A. tamarense. Opponents of the project cite the time series
described above and argue that an adverse impact of the outfall will be an increase in harmful or toxic algal species within the Bay.
The stakes in this controversy are huge and the scientific uncertainty significant.
The public, the press, and regulatory officials are demanding predictions and answers, yet their expectations exceed our present capabilities. Competitive outcomes in phytoplankton species selection and succession
cannot yet be predicted, nor can the relative effects of natural versus anthropogenic
factors be resolved. To address the concern that the phytoplankton species composition will change with the different quantities and
ratios of nutrients in the effluent from the new outfall,ecosystem-level models of the Bay are required that are a decade or more away. Even
when the focus is narrowed to a few key HAB species, their responses within the Bay ecosystem cannot be estimated with any accuracy because their nutrient requirements
have not been well-characterized in laboratory studies, nor do we even have ways to determine their nutrient status during present-day blooms.

The potential stimulatory influence of anthropogenic nutrient inputs on HAB incidence is certainly one of the more pressing unknowns we face, and it will require a focused commitment of resources and effort
greatly in excess of what has been devoted to the topic until now. Time-series analysis of
existing data bases for phytoplankton communities and variables such as major nutrients or pollutants is required, and where such data are lacking, long-term monitoring programs of at least 10-years duration must be initiated in key regions where anthropogenic changes are anticipated. Laboratory studies of the stimulatory effects of chemicals contained in effluents or terrestrial runoff are also needed, as are kinetic studies and other experiments that can quantify the nutritional
requirements and uptake capabilities of HAB species.

Offshore Red Tide-Associated Mortalities and FWRI Event Response (Updated August 10, 2005)

During the first week of August 2005, FWRI received reports from diving and fishing charter businesses of mass mortalities of fish and other animals inhabiting reefs. Reports also mentioned an odor like rotten eggs and divers’ silver jewelry and coins turning black. These reports spanned a geographical area extending from New Port Richey south to Sarasota and from approximately 3 to 23 miles offshore. It is estimated that bottom communities within an approximate area of 5,600 km² have potentially been affected. Organisms affected include dead fish present on the bottom (ranging from baitfish to goliath grouper) as well as dead sponges, corals, worms, mollusks, crabs, sea urchins, starfish, and sea turtles. Bottom visibility was also reported as being significantly reduced. Large fishing boats have also reported severe declines in catches the previous week.

Although these mortalities are linked to the persistent red tide of the toxic dinoflagellate Karenia brevis off the central west Florida shelf (Florida Red Tide Current Status), FWRI is investigating the potential for secondary effects due to the presence of toxins, hypoxia (low dissolved oxygen), and/or anoxia (no dissolved oxygen). We are examining data from our ongoing monitoring program of the existing red tide. FWC divers were transported offshore August 6, 7, and 8 by volunteer dive and fishing charter businesses (Narcossis, Reef Tours, and Wolfmouth Charters) and by Gulfstream Gas Corporation. Water, sediment, and biological samples were collected for testing and to document the status of both the red tide and resident biota. Additional samples were collected by Tanks-a-Lot. Red tide and bottom sampling protocols will be incorporated into other existing state, federal, and private studies to maximize sampling efforts for offshore locations. Additionally, the NOAA/NOS/NCCOS/CSCOR HAB (Harmful Algal Bloom) Event Response Program is providing funding for a 3-day research cruise (August 10, 11, and 12) to map the areal extent of the bloom and any resultant low-oxygen regions and to conduct diving operations. A large-scale assessment of the potential biological and economic impacts of this red tide on the offshore reef communities would require significant additional funding and logistical support.

The following map depicts the geographical extent of the reports, confirmation of bottom mortalities, red tide monitoring transects, and other observations. The map will be updated with new observations and sampling efforts as they become available. Preliminary results provided through the volunteer effort show that water samples from 4, 9.5, and 12 miles offshore, west of Clearwater, had low Karenia concentrations in surface samples at 4 miles and medium Karenia concentrations at 9.5 and 12 miles. Since no Karenia was detected in bottom samples at all three locations, the bottom mortalities could be attributable to secondary effects of red tide (red tide toxins, low dissolved oxygen, or no dissolved oxygen). Sediments are currently being tested for toxins. During anoxic (no dissolved oxygen) conditions, hydrogen sulfide is produced by bacteria, resulting in a rotten egg smell. The hydrogen sulfide would cause silver jewelry/coins to tarnish. On Monday, August 8, FWC divers reported no evidence of bottom mortalities in 77- to 80-foot depths (approximately 19 miles offshore of Clearwater) and observed healthy sponges, octocorals, stony corals, gag groupers, barracuda, and bar jacks. Inshore (50-foot depths and less), however, divers’ observations confirmed the mass mortality reports.

In the summer of 1971, a red tide caused mass mortalities of reef inhabitants over 1,536 km² of the west Florida shelf in the same general area as the current red tide. Dr. Gregory Smith (of what is now the FWC Fish and Wildlife Research Institute in St. Petersburg, Florida) concluded that extensive die-offs caused by K. brevis red tides are possible on reefs less than 130 feet in depth. Subsequently, Dr. Smith reported that recolonization of reef fishes was seemingly complete 18–24 months after the red tide and after 5 years the fish species composition was basically identical to that prior to the red tide. It was further proposed that widely fluctuating sea temperatures, turbidity, red tides, and temporary anoxia associated with certain blooms are among the primary factors regulating structure of fish populations in the eastern Gulf of Mexico. The recovery of other reef-inhabiting species is less well-documented. Further information on the impacts and recovery of the organisms in this central west Florida shelf region after the 1971 red tide event can be found in the following references:

Smith, G.B. 1975. The 1971 red tide and its impact on certain reef communities in the mid-eastern Gulf of Mexico. Environmental Letters 9(2):141–152.

Smith, G.B. 1979. Relationship of eastern Gulf of Mexico reef-fish communities to the species equilibrium theory of insular biogeography. Journal of Biogeography 6:49–61.

Steidinger, K.A., and R.M. Ingle. 1972. Observations on the 1971 red tide in Tampa Bay, Florida. Environmental Letters 3:271–278.

Habas, E.J., and C.K. Gilbert. 1974. The economic effects of the 1971 Florida red tide and the damage it presages for future occurrences. Environmental Letters 6(2):139–147.

READ WHOLE ARTICLE: GOOD UPDATE JULY

Red tide remedies focus on effect, not cause

BY CATHY ZOLLO

As red tide blooms seem to grow worse and more frequent in Southwest Florida, researchers say they are making progress toward finding a way to stop or control the toxic outbreaks.

But with significant research at laboratories such as Mote Marine having begun only five years ago and the money for those investigations still measured in thousands, not millions, of dollars, the ability to stop outbreaks like the recent one that killed thousands of fish along the Southwest Florida coast may be years away.
Some environmentalists fear the paths being taken by some researchers will cause as many problems as they cure.
Scientists seeking ways to mitigate the blooms acknowledge the solutions could come with some side effects.
"Our goal is to see if we can have a toolbox of techniques that we could select among to apply toward mitigation or control of red tide when it is feasible, knowing that some of the agents that might be used might be toxic to other organisms," said Richard Pierce, director of Mote's Center for Ecotoxicology. "These would have to be very carefully controlled and only used under certain guidelines."
Prevention as a priority
Like many scientific inquiries, the quest to understand red tide has researchers following different paths.
Their credentials range from Ph.D. to garage guru and their ideas include the ordinary, like clay and ozone gas, as well as the mysterious.
Clay -- phosphatic clay left over from mining, which researchers are considering using to control red tide -- is a particular sore spot with environmental groups.
"Are we providing the phosphate industry with a way to dispose of something at the taxpayers' expense and even make a profit?" said Joe Murphy, coastal protection campaign coordinator for the Florida chapter of the Sierra Club.
He thinks it's ironic that the slightly radioactive clay from phosphate mines might be used to control red tide. Scientists and environmentalists still don't know what starts the blooms, though there is some debate about whether nutrient-rich runoff might be increasing their frequency and intensity.
That pollution comes from mining industry waste as well as runoff from agriculture and urban areas.
Phosphate is a component of fertilizer, and all algae, including toxic red tide's Karenia brevis, are plants, reasons Murphy.
He says prevention should be the primary focus.
"The first thing w

need to do is address the root problems that are causing these red tide outbreaks to last longer, be more severe and have a greater impact on our coast," Murphy said.

Possible bloom busters

Researchers at Mote are attempting to treat the blooms by smothering them with clay or saturating them with ozone.
Since the clay could come from phosphate mining residue, two problems could potentially be solved: red tide and phosphatic clay disposal. Mixed with water, the clay would be sprayed on the blooms to coat the algae and fall in clumps to the sea floor, killing the one-celled organisms. The toxin would remain active, however.

Scientists in Japan and Korea have had success treating similar blooms on their coasts with the clay, and Korea credits the method with helping reduce red tide fishing losses from $100 million in 1995 to $1 million in 1996.
So far, Mote has tested the clay in a 130-square-meter patch of red tide, but with limited success because of a swift current.
"One thing we've learned is that if the current is moving too fast the clay is not effective, but then again that helps us determine under what conditions it might or might not be effective," Pierce said.
Ozone, another substance under review at Mote, not only kills the alga but also neutralizes the toxin it produces.
Ozone is also used to treat drinking water, for pest control and in hospitals to disinfect rooms that have been exposed to contagious germs. When used against red tide, ozone reacts with the water and creates a by-product called hypobromate.
Pierce said the substance is stable for a few hours and serves to put the brakes on more red tide blooming in the area. Researchers dissolve the highly toxic gas in sea water by pumping microbubbles of it into areas where red tide is blooming.

So far, scientists at Mote have tried the ozone only in 20,000-gallon tanks, b ut they plan to someday try it in open water and perhaps use it to clean canals that become putrid after fish kills, Pierce said.
About 70 percent of the $1 million that Mote received from the state this year for red tide research will go to monitoring the blooms to better understand what causes them, what fuels them and how they dissipate.
Another 20 percent will be spent on mitigation research that includes the clay and ozone studies, with the rest of the money paying for public education and for a study of the effect of.

Red tide remedies focus on effect, not cause

 the tides on human health.

Another solution

Backyard inventor Bob Rigby's potential red tide solution falls into the category of the mysterious.

The self-styled red tide researcher whose laboratory was first a garage and is now a high school classroom won't share his formula; he fears intellectual thievery ahead of the patent he's seeking. But he says it works to kill the toxic algae.

The details on Rigby's solution are sketchy, and not even the Venice High School students testing the stuff on tiny sea creatures know what's in it.

Teachers who oversee the shoestring operation, mostly funded by $2,000 in grants from the city of Venice, have signed a nondisclosure agreement in case they figure out the formula's makeup.

So far the solution has worked to kill red tide, and it has been effective in concentrations that leave other phytoplankton and tiny sea creatures unharmed.

Officials at Mote say they've offere d to test Rigby's formula and agreed to sign the same nondisclosure agreement as the teachers. He has refused.

Rigby said there was no mention of a nondisclosure agreement, and he's protective of his formula.

"Anybody with a half a brain would know that a chemical that kills red tide is worth a fortune," he said.

The stuff -- Rigby hasn't yet named it -- would be injected via a diffuser into the water where a bloom is occurring.

Rigby said Venice High students plan to do more testing of the formula next school year, and there's hope of more funding by the city as well as the boating advocacy group Standing Watch.

More harm than good?

Not everyone in the science community believes red tide mitigation is possible. Some environmentalists think it's downright dangerous.

Researchers at the Florida Fish and Wildlife Research Institute say the blooms are too big to treat directly.

They're aiming at predicting and tracking them to allow for better management, said Scott Willis, spokesman for the institute.

That means directing fish cleanup, issuing beach warnings and informing local businesses, such as hotels, about what to expect.

Along with matter of feasibility, said Murphy of the Sierra Club, is the question about the environmental dangers of any treatment.

Clay, he said, might smother more than the algae. The toxin drifting downward with the clay could harm bottom-dwelling creatures.

Don Anderson, a senior scientist at Cape

Red tide remedies focus on effect, not cause

(Page 4)
. . . d's Woods Hole Oceanographic Institution who worked with the Japanese and Koreans on their methods, said that it is often difficult to find a footprint from the settling clay on the sea floor.

Pierce said learning about the toxin's effect on bottom dwellers is the next step in researching clay application. He said red tide does its own damage unaided by clay.

Anderson said critics shouldn't compare potential damage from mitigation to pristine conditions.

"You should be comparing it to the red tide itself," he said. "It can persist for two months."

Environmentalists are also troubled by the fact that phosphatic clay is mildly radioactive.

Pierce and Anderson, who have worked together on solutions for Southwest Florida, say a different clay might work the same way, but it would cost more.

As unpopular as clay is among environmentalists, ozone gets even less praise. Nobody fears its use more than Lori Glenn, also of the Sierra Club.

As chairwoman of the group in Lee and Collier counties, Glenn has led an effort to stop such efforts and instead focus attention on the source of the problem.

She calls ozone overkill, pointing out that everything it touches dies.

"They want to mitigate. They want to get rid of the red tide, but they don't think about the long term impacts," Glenn said. "It seems very risky to me when all we have to do is hold the polluters accountable."

Murphy said he not only blames the agriculture and development industries that are responsible for much of the nutrient pollution, but also those charged with protecting the environment.

"The real villains are the polluting industries as well as the state regulators who have given them a free pass for the last 30 years," Murphy said. "Regulatory folks are putting industry first and trying to figure out how much the public can take, not the other way around."