Florida's Harmful Algae Blooms Claims Thirteen Victims
By Donald Sutherland

Member of the Society of Environmental Journalists

Florida's first victims suffering from a syndrome of illnesses similar to those experienced by residents of North Carolina and Maryland exposed to a toxic single cell marine organism responsible for killing millions of fish have appeared in 13 people being treated and observed by Florida doctors according to officials at the Florida Department of Health.

"The syndrome is being studied in seven states under a program funded by the Center for Disease Control and Prevention, and the Florida study represents the state's first examples of a syndrome of illnesses similar to the Pfiesteria piscicida outbreaks which hit several southeast states", says Alan Rowan, an epidemiologist with the Florida Department of Health. During 1998, Florida doctors diagnosed the 13 patients ( ranging in age from 12 to 70) to have the condition called Estuarine Associated Syndrome with symptoms of skin lesions, nausea, diarrhea, memory and neurological problems similar to those suffered by fisherman, scientists, and tourists in Maryland and North Carolina who came in contact with waters contaminated by Pfiesteria, according to Alan Rowan.

Outbreaks of Pfiesteria piscicida have resulted in human health warnings issued by the U.S. Environmental Protection Agency but officials at the Florida Department of Health insist Pfiesteria has not been found in the state despite evidence of human illnesses and fish kills with lesions. They claim a similar HAB species called Cryptoperidiniopsis brodyi found in the St.Lucie, St.Johns, and Indian Rivers is possibly to blame for the fish deaths. see: http://www.acnatsci.org/erd/ea/pfiester.htm and http://www2.ncsu.edu/unity/lockers/project/aquatic_botany/pfiest.htm and http://www.epa.gov/OWOW/estuaries/pfiesteria/index.html

"Pfiesteria has not been found in Florida, and no health standard for harmful algae blooms are warranted," says Lee Demateis, spokeswoman for the FDEP Florida Marine Research Institute (FMRI). Some scientists suggest Florida government officials don't want to incite harmful algae bloom hysteria in the public, and hurt the state's pristine image for its tourist and seafood related industries.

"In Maryland the public overreacted to 2 or 3 small lesion fish kills, and it cost the state $43 million in lost revenue to seafood related industries," says Dr. Kevin Sellner, the Ecology and Oceanography of Harmful Algal Blooms (ECOHAB) Coordinator under NOAA's Coastal Ocean Program. see: http://es.epa.gov/ncerqa/rfa/ecohab.html and http://www.fmri.usf.edu/ecohab/scientists.htm and http://www.redtide.whoi.edu/hab/nationplan/ECOHAB/ECOHABhtml.html

Florida historically has experienced harmful algae blooms for millions of years, and until recently the only species to receive media attention is Gymnodinium breve, commonly known as Red Tide. In the last 22 years there have been 21 outbreaks of Red Tide in Florida and millions of dollars have been lost in seafood and tourist industries according to the FDEP. The frequency of Red Tide outbreaks and fish kills have scientists concerned that human sewage pollution from bulging coastal populations and farm chemical runoff could be contributing factors.

Over 400 million gallons of municipally treated sewage is injected underground daily through Florida's 120 coastal Class 1 underground injection control (UIC) wells and according to FDEP monitoring tests, the waste effluent is migrating into the state's largest underground source of drinking water, the Floridan Aquifer, which discharges along the coastlines.

Dr. JoAnn Burkholder, research coordinator for the Aquatic Botany Laboratory at North Carolina State University, and her team of researchers confirmed Pfiesteria and other harmful algae blooms are associated with nitrate/phosphate runoff from hog and poultry farms and human sewage. "In North Carolina there is a connection between nutrients in human waste and Pfiesteria outbreaks, and nutrients from this waste can be highly stimulatory to HABs," Dr.Burkholder says.

Mote Marine Laboratory in Sarasota, Florida has been closely monitoring and researching Red Tide outbreaks and scientists there say although Gymnodinium breve forms miles offshore it can be effected by the municipal Class 1 UIC well sewage as it nears shorelines. see: http://www.mote.org and http://www.redtide.whoi.edu/hab

"Red Tides thrive in nutrient deficient waters, but our research indicates nutrient seepage from underground swells might be feeding these organisms and Class 1 UIC sewage migrating offshore certainly isn't helping the situation," says Dr. Richard Pierce, Mote’s Director.

The big question is how many of the state's 55 different toxic species can be stimulated to grow by the nitrates and phosphates found in human sewage and farm runoff according to Dr.Jan Landsburg, a research scientist with the FDEP's FMRI."There does seem to be more outbreaks in shore regions, but it could be due to numerous factors and science has a long way to go to tie up the loose ends ," says Dr. Landsburg.

Currently, state environmental and health departments rely on common sense and local communities to warn the public of the health risks associated with Red Tide, and neither government agency has ever issued a state human health advisory for harmful algae blooms. The FDEP does ban shellfish harvesting in beds exposed to Red Tides because the organism's toxins become concentrated in the mollusks which feed on them."There are no federal standards for Red Tide contaminated shrimp or fish because they don't concentrate the toxin in their bodies, and we don't have the knowledge to tell the public whether fish caught in a Red Tide are safe or not safe to consume," says David Heil, Bureau Chief of the FDEP's Bureau of Marine Resource--Regulation & Development. "There has never been anybody I know who got ill from eating fish caught in a Red Tide," he says.

Red Tide does cause respiratory and eye irritation problems, and the FDEP advises people suffering from asthma and the elderly to avoid beaches where it comes ashore. In the last several years the FMRI found over 204 manatees that died from respiratory suffocation due to Red Tide exposure. "Right now we are advising people not to consume or touch sick or dead fish in Red Tides and other fish kill waters," says Alan Rowan. "Further research needs to be done before we would issue a health advisory to avoid waters where sick or dead fish are found in HAB waters," he says.

Highlighting the human health threats from the increasing Red Tide and other species of harmful algae blooms would devastate Florida's coastal economies according to officials at Mote and FMRI. "What's not well documented is the Red Tides impact on our state's economy," says Dr. Carmelo Thomas, research scientist at the FMRI. "The impact of fish kills from these algae blooms to the multi-billion dollar tourist economy has a halo effect with cancellation of reservations all along the coasts and people stop buying seafood," says Thomas.

Dr. Sellner cautions Florida's nutrient loads from sewage and farm runoff to coastal waters should be as low as practically possible to minimize the chances for HAB outbreaks, and their negative impact on the state's marine reliant economies. "Yes, more nutrients from sewage should support more activity, and yes there is more pollution, but the research is divided on whether these organisms are being stimulated by land pollution activities or other causes outside of nutrient loading," says Dr. Sellner. "It's completely up to Florida to develop a checklist of HAB indicators for closing rivers and beaches, however, I wouldn't let my children swim in Red Tide or enter those waters where those 13 Florida residents contacted Estuarine Associated Syndrome", he says.

Florida Bay Nutrients: Perspectives on the july 1-2, 1996 workshop

Report of the
Florida Bay Science Oversight Panel
Ad Hoc Committee on Nutrients

Submitted to the
Program Management Committee
Florida Bay Research Program

15 July 1996

SUMMARY
An Ad Hoc Committee on Nutrients convened under the auspices of the Florida Bay Science Oversight Panel participated in a two-day workshop of investigators and program managers on nutrients in Florida Bay. It was asked to evaluate the adequacy of databases and research and monitoring programs for deriving inferences about nutrient sources and processes in Florida Bay and how they may change as freshwater inflows increase in association with hydrological restoration of South Florida. The Committee's main perspectives and recommendations are summarized below:

An important determinant of the supply of nutrients to the Bay is water flow and circulation, the most poorly quantified element of which is the exchange between western and central Florida Bay. There should be a concerted effort using salinity modeling, tracers and flow measurements to quantify these exchanges and their importance in supplying phosphorus (from deeper Gulf waters) and nitrogen (from the Shark Slough plume into western and central Florida Bay).

Although nutrient concentrations in freshwater effluents from the Everglades are now adequately monitored, because of the limited duration and high variability of the record recent variations in nutrient concentrations cannot be confidently attributed to water-management practices. The transport and transformation of nitrogen across the mangrove/estuarine transition and in the coastal flows toward Florida Bay remain important unknowns.

Box models of nutrient budgets for Florida Bay should be developed which include the major forms of N and P and at least three different geographic segments - western (west of Everglades National Park boundary), central and eastern - as a parallel and contributory exercise with the planned numerical simulation model.

In the shallow, warm, well lit Florida Bay cycling and transformation of nutrients may be as important as sources and concentrations in affecting plant growth. The current research on phytoplankton and biogeochemical processes should be expanded to focus on mechanisms of nutrient cycling rather than simply making inferences from nutrient distribution patterns.

Studies of nutrient limitation have shown that nitrogen limits phytoplankton growth in the western Bay, several nutrients may co-limit growth in the central Bay, and phosphorus typically limits growth in the eastern Bay. Understanding the causes of algal blooms now requires process studies using modern tracer and enzymatic techniques, intense time-series rather than semi-annual or monthly measurements, and field or mesocosm, as well as in vitro, experiments. The Program Management Committee (PMC) should explore opportunities for engaging experts in such approaches and facilitating the intense multidisciplinary studies required. The data and observations in support of the divergent perspectives offered regarding the effect on the coral reefs of export of nutrients from Florida Bay of the Florida Keys Marine Sanctuary are sketchy and anecdotal. Nutrient transport mechanisms and concentrations and grazing pressure on macroalgae must be considered together in addressing this question. The Florida Bay Research Program could contribute to the first of these factors.

Concerns about the comparability of chlorophyll and nutrient data were raised. Data comparability is essential and quality assurance/quality control exercises now being undertaken should be expanded and maintained.

Inconsistency of geographic references contributes confusion and interferes with the development of scientific consensus. The PMC should oversee an effort to develop a common set of names and boundaries for regions of Florida Bay. To the extent practicable, a common set of reference sites should also be selected for field measurements and experiments.

A nutrient-plankton bloom team of investigators should be formed to facilitate interpretation and use of monitoring and research data.

The Committee fully supports the PMC's efforts to develop a coupled circulation-ecosystem model of Florida Bay as a tool to systemize data, pose hypotheses, and anticipate the effects of different water management scenarios. The coupled model should be designated to describe the dynamics of these key features of the Florida Bay ecosystem: (1) coupled hydrodynamic-nutrient-phytoplankton-water quality variability, (2) suspended sediments and their influence on turbidity, and (3) seagrass populations and their influence on sediment resuspension, nutrient cycling and geochemistry.
Although hydrologic flow and water level goals guide the restoration of the Everglades, no specific restoration goals for Florida Bay have been set which could guide research as well as management activities. A subcommittee or task force of specifically address the restoration goals for Florida Bay.

Because the freshwater effluent of the Everglades has very low concentrations of phosphorus and phytoplankton and macroalgal growth in the northeastern Florida Bay is strongly phosphorus limited, the Committee's provisional judgement is that the planned redistribution of fresh water into the Taylor Slough system will not lead to or worsen acute symptoms of over-enrichment in Florida Bay. However, the consequences of this plan have not been assessed with even simple mass balance models and must be regarded as uncertain as this point.

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NUTRIENT THRESHOLDS FOR EUTROPHICATION AND MACROALGAL OVERGROWTH OF CORAL REEFS IN JAMAICA AND SOUTHEAST FLORIDA

Brian E. LaPointe
Director, Florida Keys Programs
Division of Marine Science
Harbor Branch Oceanographic Institution, Inc.,
3754 Pine Street
Big Pine Key, FL 33043

ABSTRACT
Some scientists have speculated that recent dramatic macroalgal overgrowth of fringing coral reefs on the north coast of Jamaica resulted primarily from reduced grazing due to overfishing and die-off of the sea urchin Diadema antillarum and dismissed entirely the possible role of eutrophication. My study tested the alternative hypothesis that nutrient overenrichment was the primary factor causing the spectacular macroalgal blooms that recently developed on reefs at Discovery Bay, Jamaica, and Palm Beach County, FL. In both locations, groundwater discharges contributed to elevated water column DIN and SRP concentrations that exceeded nutrient thresholds (~1.0 :M DIN and SRP) for eutrophication on coral reefs. At Discovery Bay, DIN and SRP concentrations ranged from 5 :M and 0.12 :M on the fore reef to 28 :M and 0.33 :M around the near shore springs, respectively. High seawater DIN:SRP ratios (33:1 - 100:1), and macroalgal alkaline phosphatase activity [APA;20 to 90 :M SRP released (g dry wt)-1 h-1] and tissue C:P (956:1) and N:P ratios (45:1) indicated P-limited productivity at Discovery Bay, which was corroborated by experimental studies where P-enrichment significantly increased Pmax of the shallow water opportunistic chlorophyte Chaetomorpha linum. Recent increases in SRP concentrations of the fore reef at Discovery Bay above 0.1 :M, combined with the physical disturbance of Hurricane Allen in 1980, explains the increased standing crop biomass of Sargassum polyceratium and other macroalgae that now dominate this habitat. In Florida, DIN and SRP concentrations ranged from 0.75 :M and 0.13 :M to 3.44 :M and 0.33 :M on deep reefs (20 to 30 m) around blooms of the chlorophyte Codium isthmocladum, respectively. Lower seawater DIN:SRP ratios (<15:1) and macroalgal APA [<20 :M SRP released (g dry wt)-1 h-1] and tissue N:P ratios (36:1) suggested N-limited productivity, which was also confirmed experimentally where effects of N-enrichment significantly increased ", the photosynthetic efficiency under low irradiance. Tissue *15N ratios of C. isthmocladum ranged from +10.0 to +12.0 0/00 during the summer bloom, indicating wastewater-contaminated groundwaters as the N source supporting algal growth. These results are consistent with other case studies of eutrophication on coral reefs and refute recent speculations that reduced herbivory was the primary factor causing dramatic macroalgal overgrowth of coral reefs in Jamaica.

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MANAGEMENT STRATEGIES TO CONSERVE MARINE BIODIVERSITY

James A. Bohnsack
National Marine Fisheries Service, SEFC, Miami Laboratory
75 Virginia Beach Dr.
Miami, FL 33149, USA

Jerald S. Ault
University of Miami, Rosenstiel School of Marine and Atmospheric Science
Division of Marine Biology and Fisheries
4600 Rickenbacker Causeway
Miami, FL 33149, USA

INTRODUCTION
Biodiversity is the variety of living organisms and their habitats: the structure, composition, dynamics, and function of living systems acquired over millions of years of evolution. Marine biodiversity is extremely rich but is poorly understood and has only recently become the subject of conservation concerns (Norse, 1993). Biodiversity refers to the spatial organization of plants and animals in a hierarch at the genetic, organism, population, species, community, ecosystem, and seascape levels (Hughes and Noss, 1992; Norse, 1993). Major threats to biodiversity are habitat destruction, environmental changes, and overfishing (Upton, 1992). Losses of biodiversity at the genetic and species levels are of special concern because they are permanent.

This article focuses on management strategies that protect marine biodiversity and promote sustainable resource use. These strategies are evaluated in terms of their ability to fulfill three criteria: economic efficiency, flexibility, and ease of implementation. The emphasis of current fishery management practice is on fishing, which includes all extractive harvesting activities. Fishing is socially and economically important, but if done improperly or to excess, fishing can threaten biodiversity (Huntsman, 1994). It is also important to protect water quality and habitat from other destructive human activities that include poor land use practices and pollution, especially the release of excess sediments, nutrients, sewage, and toxic materials. Other activities that can threaten marine biodiversity include oil and gas extraction, vessel traffic, and release of diseases and parasites from mariculture.

In this paper we describe a management strategy to conserve biodiversity; a strategy incorporating impacts on habitat, and the biological, social and economic factors of overfishing. We propose new management tools including use of habitat restoration and marine reserves to maintain biodiversity and sustain fisheries. Finally, we review an application in the Florida Keys National Marine Sanctuary in the context of some testable scientific hypotheses.

CONCLUSIONS
At a time when diversity of oceanic fishes is threatened, fishery management can no longer strive simply to maximize yield while ignoring biological interactions, the physical and biological environments, and impacts of fishing gears and catches on habitat and biodiversity. There is a clear need to improve monitoring methods and change from single species management to ecosystem management to protect marine biodiversity and promote sustainable use. Research and education are essential to increase public appreciation of biodiversity and the impacts of human activities. Both resource managers and users need to develop realistic expectations and a risk-averse philosophy toward resource exploitation and management effectiveness. To be effective, decision makers must maintain a systems view of the resources. Proposed marine reserves in the Florida Keys present a unique research opportunity to clarify the relative impacts of fisheries exploitation and oceanographic processes in determining reef biodiversity and abundance of reef resources.

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FLORIDA'S CORAL REEF: THE KEYS ARE IN OUR HANDS
reprinted from In Grove Miami Magazine

by Dana Robbin

North America's only living coral reef appears to be thriving. Six miles offshore and some 158 miles in length, this underwater Eden swings like a charm on a bracelet from a band of tiny islands called the Florida Keys, out past the Dry Tortugas.

Iridescent and vital, it pulses with life, with jellyfish, sponges, anemones, and snails…turtles, crabs, spiny lobsters and rays…purple sea fans, and soft stony corals.

The tiny reef-building coral "polyp" is no bigger than a pinhead. Encased in a calcareous (containing calcium) exoskeleton, it is fragile and delicate; a simple little creature with a life span of centuries that, together with millions of other little microscopic animals, creates living coral formations in shapes of leaves, fans, brains, and tendrils of plants. Adding new coral to old, and passing nutrients through, they build ever so slowly; some less than an inch per year.

The coral reef of the Keys is one of the world's richest ecosystems. It is home to 150 species of tropical fish, and 50 species of coral. Surrounded by dense mangrove forests and flowering seagrass beds, it provides a nursery and breeding habitat for one third of Florida's endangered species, including the manatee, Key Deer and crocodile. Yet this coral barrier is itself in peril.

Once insulated from the Miami mainland and the stresses of urban living by a thin, treacherous roadway and 32 bridges, the Keys' corals have become the world's busiest dive destination. Busier even than Australia's Great Barrier Reef that at 1,240 miles in length, is the world's largest ecosystem and the only living structure visible to the naked human eye from outer space. In fact, ten times busier, and on the critical list.

The Keys' corals are dying. Diseases of known and unknown origins are breaking out in epidemic proportions. Algal blooms of unprecedented size are suffocating our dive sites. Once pristine waters stand murky and green. Question is: Is it too late?

Not according to Craig and DeeVon Quirolo, cofounders of a non-profit grass roots organization established in 1986 to "preserve and protect" the living coral reef. If we didn't think it could be done, we wouldn't be trying," says DeeVon, ex-law student turned natural-food restaurateur turned publisher and full-time environmentalist.

She and her husband Craig met in the early 1970's. At that time, he was running some of the first snorkeling charters off Key West in aquarium-glass waters that magnified schools of tropical fish resplendent over star and brain corals. Also at that time, the reef that had, throughout history, defined the island's character and secured its economic prosperity by snagging the treasure-chested hulls of wooden sailing ships for opportunistic pirates and wreck salvors, was becoming the lolita of a burgeoning tourist industry.

Having weathered 450 million years, hurricanes, tornadoes, and two world wars, the coral reefs of the Keys have met their march: human beings. Virgin strands of branching corals like elkhorn and staghorn were toppled by anchors mindlessly tossed. Soft coral "polyps" were crushed by careless divers crawling hand-over-hand over corals that appeared immortal, but were not.

The Quirolos were realists. They understood that, having found this 18-karat gemstone, no one was moving north. So they set out to define a reef-saving etiquette for the 75,000 Keys' residents, and the millions of tourists. They designed and installed 116 mooring buoys, giving boaters an alternative to dropping anchor on the fragile corals. At the edge of Key West Harbor, they set up an environmental information center. They held information symposiums for the hospitality industry, created a "sea-fan" membership campaign, hosted film festivals on marine conservation, sponsored beach clean-ups, developed school curriculum programs, helped underwrite valuable marine research, and launched an underwater photo monitoring program to keep tabs on changes at the reef.

Their "Do not touch, stand on or take the coral" message was translated into French, German, Italian, Japanese and Spanish. And on Earth Day, 1990, a top honor was presented: Then President Bush singled out the environmental group as his 123rd "Point of Light," for its success in turning the Keys' attitude towards their reef from benign neglect to informed stewardship.

Then the water quality washed up as the number one coral-killer. The job got even tougher. "Now," says DeeVon, "we're into the hard stuff, the issues that will take lifestyle changes to resolve."

Like "nutrient" rich waters that feed disease and algae growth from Florida Bay and Miami's Biscayne Bay. Like impacts from the Everglades, South Florida's agricultural areas, and West Florida's phosphate mining. Like Keys' own land-based pollution; the inadequate and primitive sewage treatment facilities, chemical fertilizers, illegal cesspits, and pesticides.

To save the living coral, so akin to human bone it can be used in transplant surgery, the Quirolos and their team of volunteers and experts have had to take on the Big Leaguers; becoming coalition builders and advocates in addition to educators, tackling governmental bodies and manufacturing associations.

Not without avail: A ten year ban on offshore oil drilling, cancellation of navy explosives testing, Florida's Keys National Marine Sanctuary legislation, a phosphate ban for Monroe County, and restrictions on the harvesting of marine life, are but the opening credits on a list that's long, and lengthening.

Still, the Quirolos warn, "Without aggressive water quality regulations, enforcement, and no-use zones for recovery and monitoring, the reef will not be here for future generations."

Battered, the coral garden is in our hands.

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Dr. Gert Jan Gast - Nutrient pollution in coral reef waters with data from Curaçao waters

Syllabus for the Reef Care Curacao workshop on nutrient pollution with Dr. Brian Lapointe, Curacao, 23 Oct 1998

Living nature can be divided in different areas with specific plants and animals. The group of organisms in a certain area and the way in which these organisms interact with each other is called an ecosystem. Examples of ecosystems are coral reefs, deserts, taigas, rain forests and savannas. The outward boundaries of ecosystems are set by physical factors such as temperature, rain and geological shape of the land. Polar regions are different from the tropics in temperature, but within the tropical zone there are wet and arid areas. The geological shape can mean plains or mountains, small islands or large continents, shallow or deep sea. Organisms are adapted to live under specific circumstances and the occurrence of such circumstances determines which animals and plants can be found where. These influences are called abiotic factors. Relations between the organisms determine the detailed composition of that ecosystem (e.g. predators eating prey, trees create a place for birds to build a nest, corals and sponges compete for space on a reef flat, etc.). Such influences of organisms on each other are called biotic factors. The availability of nutrients depends on a combination of abiotic and biotic factors.

The term 'nutrient' in a broad and general sense means food. Organisms need nutrition or food to obtain the necessary energy and building materials to grow, maintain and reproduce. However, more commonly the term nutrients is used for the chemical elements nitrogen and phosphorus. With nutrient pollution or eutrophication we mean an increase in nitrogen (usually as ammonium or nitrate) and phosphorus (as phosphate) in a natural environment. Before I go into the details of eutrophication, let me first explain the role of the elements in an ecosystem.

Plants fix energy from sunlight into organic material in a process called photosynthesis. Plant eating animals (herbivores) obtain the necessary energy to live by eating plants. Animal eating animals (carnivores) eat herbivores or other carnivores. This way energy is transferred through the food chain from plants to herbivores to carnivores. It is important to realize that there is only one input in the system: plants fixing sunlight. All other organisms depend on the presence of plants for their energy. Energy is transferred through the ecosystem until it is lost.

Aside from fixing energy into organic material, a plant needs building materials to make itself: stem, leaves, roots, flowers; the whole thing. These materials usually expressed as their chemical elements, e.g. carbon (C), nitrogen (N), phosphorus (P), hydrogen (H), oxygen (O), etc. In reality these elements are bound in organic molecules. C, O and H form the largest part of living or organic matter. Nitrogen is a necessary element in for example protein molecules and phosphate occurs in cell membranes. Also, both elements N and P are necessary parts of DNA. Other elements are needed in small amounts to form a body, such as iron or copper. In a whole living body these materials are needed in certain amounts. Plants in sea consist of C and N and P in a ratio of approximately 106:45:5. Plants need to obtain these different elements in different amounts from the environment. C is present in CO2. H is in water (H2O), N in NH4 (ammonium) or NO2 (nitrate) and P in PO4 (phosphate). O is present in almost all of these molecules. The ratio in which these building materials are available is mostly not the same as the ratio in which they are needed. Of one of these elements there will be less available relative to the others, which means that this element becomes limiting for growth. In the sea there is of course water enough and H and O are never a problem. CO2 dissolves into the water from the atmosphere and is usually sufficiently present as well. The limiting nutrient is most commonly N or P (although there are areas where neither N or P, but iron is limiting). Hence the common use of the term nutrient pollution for excess inputs of ammonium (NH4), nitrate (NO3) and phosphate (PO4).

Like energy, nutrients are transferred through the ecosystem as one organism eats another. There is, however, an important difference: nutrients are not used up, but become released again. Animals that eat plants burn 80-90% of their food for energy and use only the rest for growth of their body and reproduction. This means that they eat far more N and P than they need and the surplus has to be excreted. Also every organism dies at some time and when bacteria break down the remains, nutrients become available again. The essential difference with energy is that nutrients are cycled through an ecosystem. Plants take up inorganic nutrients from their environment and fix them in organic material, animals eat plants and excrete organic nutrients, and bacteria convert these back to inorganic nutrients, which can be used by plants again. As long as none are lost, nutrients could in theory be recycled forever through an ecosystem. In reality, ecosystems are not closed and nutrients are imported and exported: animals move in or away, water currents bring or take away organisms and molecules, dead organisms disappear into deep water, etc. In Long living ecosystems the import and export of nutrients are usually balanced: as much comes as goes out.

One of the major effects of humans on their environments is that we change the nutrient balance by increasing the nutrients concentrations. We use fertilizers in agriculture, which is nothing else than nutrients for plants we wish to grow. These plants cannot use all the nutrients we supply and much of the loading is lost to the environment. Sewage consists of nutrients in organic and, if treated in a sewage plant, inorganic forms. These nutrients are generally discharged into our environment. At the same time we often reduce the capacity of nature around us to use these nutrients by removing the natural vegetation for agriculture or urban development. Humans eutrophy their environment and the larger and denser the population is, the stronger the nutrient pollution.

So, why is this a problem? We are basically giving plants and thereby all the animals in the ecosystem materials that they need, don't we? The answer is that reality is not that simple. Yes, plants need nutrients, but only a limited amount. The problem is that increases in nutrients lead to changes in the ecosystem. Some plants are specialized to survive in an environment with low nutrient concentrations, while other plants dominate with high nutrient concentrations. When nutrient levels are increased the ecosystem shifts from low nutrient specialists to high nutrient specialists. Ultimately this leads to completely different ecosystems under long term eutrophication. Generally this leads to a reduction of the diversity within ecosystems and variation between ecosystems.

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Mercury and Selenium Tissue Concentrations in Double-Crested Comorants: Correlation with Histopathologic Findings

RH Poppenga, DVM, PhD, WJ Birdsall, PhD, RY Reams, DVM, PhD, and RB Quinn
New Bolton Center, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA 19438

ABSTRACT

Concentrations of total mercury (g) and selenium (Se) were determined in fresh brain, liver and kidney tissues from a series of double crested cormorants (Phalacrocorax auritus) presented to an avian wildlife rehabilitation center located in the Florida Keys. In addition, a variety of formalin-fixed tissues were examined histologically in an attempt to determine a likely cause of death for each bird.

A specific attempt was made to correlate tissue concentrations of Hg with histopathologic lesions in the central and peripheral nervous systems compatible with Hg intoxication. In this series of cormorants, liver Hg and Se concentrations were highly correlated. However, there was little correlation between liver and brain Hg concentrations and no correlation between brain and/or liver Hg concentrations and hispathologic findings.

Results of this study support the hypothesis that Se protects against high tissue Hg concentrations and that it is not possible to determine the adverse health consequences of high tissue Hg based upon its measurement in organs such as brain and liver.

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Woods Hole Oceanographic Technical Report, WOI-98-03

The Environmental Impacts of Boating proceedings of a workshop held at Woods Hole Oceanographic Institution, Woods Hole, MA

ABSTRACT

Substantial impacts of boating activity discussed at this workshop include: sediment and contaminant resuspension and resultant turbidity; laceration of aquatic vegetation with loss of faunal habitat and substrate stability; toxic effects chemical emission of boat engines: increased turbulence; shearing of plankton; shorebird disturbance; and the biological effects of chemically treated wood used in dock and bulkhead construction.

These discussions revealed that many of the issues of concern remain inadequately defined and described. But sufficient hard data was referred to or presented to substantiate the inference that recreational and commercial boat operation is far from a benign influence on aquatic marine environments.

This is particularly so in temperate climes due to the unfortunate synchrony, with only a few exceptions, between peak seasons for boating and the occurrence of planktonic, embryonic and larval stages of vertebrates and invertebrates in estuaries and coastal waters.

Therefore, the chance of plants and organisms being affected by power boat operations appear to be substantial in shallow, heavily used boating areas such as those along the entire U.S. eastern and Gulf Coasts. As such, motor boat operation should be conducted and managed in such a manner as to minimize those impacts.

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Yellow-Blotch disease outbreak on reefs of the San Blas Islands, Panama Coral Reef (1999)

(D.L. Santavy*, E.C. Peters, C. Quirolo, J.W. Porter, C.N. Bianchi.
Corresponding author: U.S. Environmental Protection Agency, Gulf Ecology Division, Gulf Breeze, FL., 32561, USA. e-mail: santavy.debbie@epamail.epa.gov)

Esther C. Peters
Tetra Tech, Inc.
10306 Eaton Place, Suite 340
Fairfax, VA 22030
(703) 385-6007

An extensive outbreak of coral disease was observed affecting the scleractinian corals Montastrea Faveolata and M. Annularis at San Blas, Panama, in the eastern Caribbean region. The first report of this disease referred to it as "yellow-band disease", and it was observev on colonies of M.faveolata on reefs off Key West, Florida (Reeves 1994). Santavy and Peters (1997) proposed the name "yellow-blotch disease" (YBD based on the unusual pattern of yellowish tissue lightening, and to distinguish it from the yellow band disease reported by Korrubel and Reigl (1998) in the Arabian Gulf. Yellow-blotch disease is characterized by circular to irregularly-shaped patches or wide streaks of lightened transluscent tissue, occuring in no particular pattern on the surface of the colony, but more common on the uppermost surfaces. The color of affected tissue is yellow, not pale brown to white as occurs in bleaching.

Occasionally, bright white transluscent patches of tissue appear adjacent to yellowish ones. The affected tissues otherwise appear grossly normal. The lightened patches frequently, but not always, are adjacent to or form a margin around algal/sediment accumulations on dead coral skeleton. No "band" of clean, denuded skeleton is usually present.

The disease was present on most reefs examined at San Blas in 1996. At the western tip of the Salar Islands group (approximately 78 degrees 48.5'W,9 degrees 31'N), 6 to 18 m deep on the forereef, about 5% of all M. faveolata colonies were affected. Affected colonies had from one small patch of discolored tissue to numerous large patches of algal/sediment accumulations adjacent to yellowish tissues with extensive tissue tissue loss. Yellow-blotch disease was not observed here 25 years ago. The reefs are considered to be relatively spared from anthropogenic pollution and diving pressures. However, our assessment is that a major die-off of M. Faveolata is occurring in San Blas, which is of geological significance since it is the primary reef builder.

Similar signs of disease have been observed on Montastrea spp. Elsewhere, including the severly affected Netherlands Antilles (TJ Goreau and JM Cervino, AW and RJ Bruckner, per. Commm.); Key West; Negril, Jamaica; Isla Cocos and Marie La Gorda, Cuba; and Guanaja and Bay Islands, Honduras. However, the presence of unaffected large and small colonies of M. faveolata suggests that some colonies might be resistant or have not been exposed in a manner that results in an active infection.

Acknowledgement We thank Ken Clifton, the Captain and crew of the Daiquiri, the Smithsonian Tropical research Institute, and the Kuna Indians for their assistence in San Blas. Key West observations were supported by Reef Relief.

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Florida Keys Carrying Capacity

(James F. Murley Secretary Florida Department of Community Affairs Tallahassee, FL.)

The Florida Keys are home to hundreds of rare, exotic oceanic wonders. Known for their lush tropical hardwood hammocks, pine rocklands, and rocky shoreline, the Keys provide a breeding ground for the third largest coral reef system in the world, lush sea grass beds, unique terrestrial and natural communities.

But the Keys are dying, being choked off by too much human intrusion or causes about which no one is absolutely certain. The genesis of this malady must be determined and mitigated; otherwise, one of the natural wonders of the world will cease to exist.

In concert with the U.S. Army Corps of Engineers, the Florida Department of Community Affairs (DCA) is taking steps to remedy this plight by conducting a Carrying Capacity Study. The Keys, while they are not a sandy shoreline - they are basically limestone remnants of the receding sea - provide an unbelievably beautiful area for residents and tourists. Over 80,000 people reside in these small keys connected by U.S. Highway 1. Another 2 million visitors each year come to enjoy the many attractions of the area, and they create the kinds of coastal impacts that exist throughout the shorelines of the United States. They are particularly concentrated and have significant adverse impacts on the wonderful, valuable coral reef, which protects the Keys but also provides the tourist attraction to begin with.

With concerns about human impacts, the changing natural environment, and sustainability issues resulting from the South Florida Restudy, the DCA is examining some extraordinary new ways of approaching the long-term sustainability of the Florida Keys. This effort is referred to as the Carrying Capacity study, one of the critical projects authorized by the water Resources Development Act (the Authority of the Corps of Engineers for conducting the South Florida Restudy and the water-management activities that are so critical to the Everglades (e.g., storing water for re-supply and estuaries). Within that huge hydrology study, there exists a place to study the very unique issues dealing with the Florida Keys.

The Florida State Government is overseeing many decisions of the local officials. In partnership with them, the state is trying to provide extra resources to help them with their unique problems. Those problems are substantial in the area of environmental quality, intershore pollution from cesspits, impacts on the coral reefs, threats to over 100 species, and endangered and threatened species including the Florida Key Deer, which has its habitat on Big Pine Key and is significantly impacted by transportation and other residential impacts.

The Keys are one of the most difficult areas to plan for emergency evacuation. The DCA is responsible for emergency management in the state and, since Hurricane Andrew, has concentrated on its ability to evacuate citizens and visitors from the Keys. At least 24 hr are needed to evacuate the Keys. It is the worst type of forecast for any part of Florida, removing people within time of the predicted warning system from the National Oceanic and Atmospheric Administration weather service. Hence, hazard mitigation is an important part of the Carrying Capacity Study, along with environmental quality.

With cooperation from the Corps' Jacksonville District for the past several months, the DCA has been designing a scope of work for the Carrying Capacity Study. It is not an easy task to discuss real and perceived understanding of the facts as they relate to the issues with people who have been working in the Keys, to arrive at a consensus with which everyone will initially be comfortable about the strategy for advancing with this work over the next three years. This consensus is believed absolutely critical, but the DCA does not initially have the cooperation and input of some valuable players. When such studies take place, there can be people on the outside commenting from their perspective about what is being done correctly. It is desired to have as many pertinent people working on the design of the scope of work as possible. The design is in its final phases.

The Carrying Capacity Study is intended to be a tool transferable to other similar areas in the United States, and perhaps island nations throughout the world, that allows decision makers at the local, state, and national levels to evaluate future decisions to determine whether they will reach certain sustainable thresholds or benchmarks that the DCA has developed for the Keys. If certain development patterns are allowed to proceed, the Carrying Capacity Study must determine if that will create demands on the system for treating the effluents and various other aspects of community development beyond the cost or capacity of that available in the Keys.

Besides scientific, social, and economic information, the DCA is going to have to deal with the difficult task of understanding the values of people, the citizens of the Florida Keys. The DCA must determine if that will create demands on the system for treating effluents and various other aspects of community development beyond the cost or carrying capacity of that available in the Keys.

Besides the scientific, social, and economic information, the DCA is going to have to deal with difficult task of understanding the values of the people, the citizens of the Florida Keys. The DCA must understand what the people want their communities to be like, because they may well set some of the thresholds from their perspective that may be different from what may be arrived at from scientific and engineering aspects.

The South Florida Restudy will set trends for one-third of the state of Florida, probably 7 to 10 million people, over the next 50 years. As the Carrying Capacity Study of the Keys progresses, it will provide us with the experience and benchmarks of how the rest of the two-thirds of the state could work. The DCA will learn a lot from the Carrying capacity Study that can be used in the rest of the state, and hopefully the results may be applicable to other regions of the country and around the world.

BG Robert L. VanAntwerp asked Mr. Murley if he could project the number of people expected in the Keys, beyond the 80,000 permanent residents there now, and if he felt that number to be fairly fixed over the next 5 to 10 years. Mr. Murley responded that the number will grow, but not rapidly because of an interim rate-of-growth ordinance unique to that area of Florida, which establishes a maximum number of 230 new units allowed each year.

BG VanAntwerp asked the time line for the study. Mr. Murley said that his goal is for the study to be underway by 1, July. He said he hoped a year from now he would be able to report back on the final study design, the actual methodologies that consultants are using in the field. COL Joe R. Miller stated that the District was looking to complete the study by August 2001, so it is going to be about a 3-year effort. Mr. Murley agreed that was correct.

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