Status of U.S. Harmful Algal Blooms:Progress towards a National Program

Harmful algal blooms kill coastalmarine wildlife and poison humans.

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STATUS OF U.S. HARMFUL ALGAL BLOOMS:PROGRESS TOWARDS A NATIONAL PROGRAM

This publication was prepared byDonna D. Turgeon, Kevin G. Sellner, and Donald Scavia,

National Ocean Service, National Oceanic and Atmospheric Administration,U.S. Department of Commerce

andDonald M. Anderson, Biology Department, Woods Hole Oceanographic Institute

With contributions fromJohn Heisler and Kay Austin, U.S. Environmental Protection Agency

Michael McGeehin, Centers for Disease Control and PreventionAlan Dearry, National Institute of Environmental Health Service

Sherwood Hall, Food and Drug AdministrationDavid Garrison, National Science Foundation

Joan Cleveland, Office of Naval ResearchJanet Campbell, National Aeronautics and Space Administration

Michael Mac, U.S. Geological Survey, Department of InteriorRobert J. Wright, Agricultural Research Service, U.S. Department of Agriculture

This publication was prepared byDonna D. Turgeon, Kevin G. Sellner, and Donald Scavia,

National Ocean Service, National Oceanic and Atmospheric Administration,U.S. Department of Commerce

andDonald M. Anderson, Biology Department, Woods Hole Oceanographic Institute

With contributions fromJohn Heisler and Kay Austin, U.S. Environmental Protection Agency

Michael McGeehin, Centers for Disease Control and PreventionAlan Dearry, National Institute of Environmental Health Service

Sherwood Hall, Food and Drug AdministrationDavid Garrison, National Science Foundation

Joan Cleveland, Office of Naval ResearchJanet Campbell, National Aeronautics and Space Administration

Michael Mac, U.S. Geological Survey, Department of InteriorRobert J. Wright, Agricultural Research Service, U.S. Department of Agriculture

EXECUTIVE SUMMARY

This document was prepared in response to a request by the House Committee onAppropriations. In its Departments of Commerce, Justice, and State, the Judiciary, andRelated Agencies Appropriations Bill, Fiscal Year 1998, the Committee “urged NOAA’s CoastalOcean Program to continue its efforts to establish a National Harmful Bloom program thatwill expand the current geographic scope of studies on the ecology and oceanography ofharmful algal blooms (ECOHAB) to additional geographic areas and conduct research onthe means to prevent, control, and mitigate blooms and their effects.” Because the Depart-ment of Commerce (DOC) efforts through the National Oceanic and Atmospheric Adminis-tration (NOAA) are cooperative with other Federal agencies, the Committee requested areport “outlining interagency efforts and progress.” Here is that report.

Harmful algal blooms are an increasing worldwide threat with significant impacts onU.S. coastal regions. A harmful algal bloom (HAB) in local waters can have serious conse-quences, depending on the species, that range from killing fish and other wildlife to makingshellfish poisonous and perhaps deadly to consumers. Recently, blooms have occurred innew coastal areas and new species have also appeared, catching watermen, residents,and local officials off-guard (e.g., “Pfiesteria hysteria” in mid-Atlantic coastal waters).

About five years ago, DOC/NOAA supported a workshop that resulted in a National Plan(Marine Biotoxins and Harmful Algae: A National Plan) and set in place a process that wouldeventually evolve into an interagency national program to understand and ameliorate theimpacts of coastal HABs. DOC/NOAA and the National Science Foundation (NSF) spon-sored a second report (ECOHAB: The Ecology and Oceanography of Harmful Algal Bloomsa National Research Agenda). This National Research Agenda is the blueprint for ECOHAB,the first Federal research program on the ecology and oceanography of HABs. ECOHABresearch is currently supported by the DOC/NOAA, NSF, the U.S. Environmental ProtectionAgency, the Office of Naval Research, National Aeronautics and Space Administration, andthe U.S. Department of Agriculture. Recently, DOC/NOAA and the National Fish and Wild-life Foundation sponsored the development of a third strategic report (Harmful Algal Bloomsin Coastal Waters: Options for Prevention, Control, and Mitigation), blue-printing needs fora national management strategy for HABs. The Ad Hoc Interagency Task Force on MarineBiotoxins and Harmful Algae, comprised of agency representatives and academic research-ers, guides, directs, and supports the U.S. HAB program. The National Office of MarineBiotoxins and Harmful Algal Blooms in Woods Hole, Massachusetts, distributes HAB infor-mation and assists the national effort. This report summarizes the status of U.S. coastalHABs, collective federal HAB efforts, and outlines interagency U.S. cooperation to betterguide HAB research, prevention, control, and mitigation.

Massive mortalities of wild fish due to coastal HABs. Severe economic losses of farmed fish due to HABs.

1HABs-

INTRODUCTION

U.S. coastal waters periodically expe-rience extensive blooms of algae that im-pact living resources, local economies, andpublic health. This phenomenon is notunique to the U.S., but is global, with ex-panding problems in Scandinavia, westernEurope, the Mediterranean, South America,Asia-Pacific islands, and other coastal na-tions. Increasingly frequent incidences andthe serious impacts of some bloom eventsin the U.S. have led to an integrated, inter-agency HAB program that addresses needsfor safeguarding public health, limitingbloom impacts on coastal resources, anddeveloping the capability to predict whenand where toxic blooms will occur.

Among the thousands of species ofmicroscopic algae at the base of the ma-rine food chain are a few dozen that pro-duce toxins. Algal species make their pres-ence known sometimes as a massive“bloom” of cells that may discolor the water(Figure 1). Other species, in dilute, incon-spicuous concentrations of cells, are no-ticed because they produce highly potenttoxins that either kill marine organisms di-rectly, or transfer through the food chain,causing harm at multiple levels.

Blooms of toxic algae were commonlycalled “red tides,” since, in the case of some

dinoflagellates, the tiny organisms may in-crease in abundance until they dominate theplanktonic community and tint the water red-dish with their pigments. Because other bloomsmay tint the water bright green or adverse ef-fects can occur when some algal concentra-tions are low and the water is clear, the scien-tific community now uses the term “harmfulalgal bloom” or HAB. This descriptor appliesnot only to toxic microscopic algae but also tonontoxic macroalgae (seaweeds) which cangrow out of control and cause such ecologicalimpacts as displacing indigenous species, al-tering habitat suitability, and depleting oxygen(Figure 2). HAB impacts include human illnessand death from ingesting contaminated shell-fish or fish, mass mortalities of wild and farmedfish, and alterations of marine food chainsthrough adverse effects on eggs, young, andadult marine invertebrates (e.g., corals,sponges), sea turtles, seabirds, and mammals.

What is the problem?

Fish lesions, fish kills, irritating health prob-lems for some Maryland Eastern Shore resi-dents, and depressed commercial fish salesfrom the Chesapeake dominated lastsummer’s local news media, capturing the at-

Figure 1. Dense microalgal blooms can color the water brightgreen, red, or brown, and shade bottom plants and animals.

STATUS OF U.S. HARMFUL ALGAL BLOOMS:PROGRESS TOWARDS A NATIONAL PROGRAMSTATUS OF U.S. HARMFUL ALGAL BLOOMS:

PROGRESS TOWARDS A NATIONAL PROGRAM

Figure 2. Dense macroalgal blooms smother bottom plantsand animals (e.g., corals and sponges) and may drift ashore.

HABs- 2

tention of state andfederal agency offi-cials. The cause—amicroscopic, toxin-producing, single-celled dinoflagellate,Pfiesteria—was to-tally unexpected andappeared to catchpoliticians andagency officials off-guard. Public alarmresulted, partially be-cause of the beliefthat this invisiblepredator was nowlurking in the Chesa-peake Bay.

Although thesetoxic cells werealarming and alien tolocal residents, HABevents are commonalong U.S. shorelines. HABs are now foundthroughout the U.S. coastal system, from theGulf of Maine through the Gulf of Mexico andnorth to Alaska. Blooms of algae have beenidentified in every coastal state and HABspecies regularly threaten coastal livingresources, restrict local harvests of fish andshellfish, divert public funds to monitoringprograms, depress local recreational andservice industries, and burden medicalfacilities.

U.S. HABs are caused by a diversegroup of organisms with serious impacts forhumans and coastal ecosystems. When toxicalgae are filtered from the water as food byshellfish such as clams, mussels, oysters,and scallops, shellfish tissues accumulatetoxins.5, 6 Typically, shellfish are only margin-ally affected, even though a single clam cansometimes accumulate sufficient toxin to killa human. Shellfish poisoning syndromeshave been given the names paralytic (PSP),diarrhetic (DSP), neurotoxic (NSP), and am-

nesic (ASP) on the basisof descriptive humansymptoms. Except forASP, all are caused bybiotoxins synthesized bymarine dinoflagellates.ASP is produced by dia-toms that, until recently,were all thought to be freeof toxins and generallyharmless.7

A fifth human illness,ciguatera fish poisoning(CFP) is caused bybiotoxins produced by di-noflagellates that grow onseaweeds and other sur-faces in coral reef commu-nities.8 Ciguatera toxinsare transferred through thefood chain from reef fishesthat eat algae to the carni-vores that feed on them

(e.g., barracuda). Similarly, the viscera ofcommercially important fish (e.g., herring orsardines) can contain PSP toxins, endanger-ing human health following consumption ofwhole fish. Whales, porpoises, manatees,seabirds, and other wildlife are victims aswell, receiving toxins via contaminated zoop-lankton or fish (Figure 3).9, 10

Impacts from other HABs occur whenmarine fauna are killed by algal species thatrelease toxins and other compounds into the

Figure 3. Toxins accumulated in tissues of small marine lifethat feed on HABs can kill large consumers like whales.

One of several new species of “phan-tom” dinoflagellates, Pfiesteriapiscicida, has a complex life cycle (dif-ficult-to-detect cysts, amoebae, non-

toxic flagellates and toxic zoospore stages). Af-fecting human health and fisheries in mid- andsoutheastern U.S. estuaries, unknown sub-stances freshly secreted by finfish stimulate P.piscida to produce several toxins that narcotizefish and cause the formation of open bleedingsores.1-4 In the laboratory, human exposure toaerosols from toxic cultures has been linked toshort- and long-term neurotoxic symptoms. Fish-ermen and others exposed to estuarine watershave also complained of similar problems, ex-emplified in the worst cases as a loss ofneurocognitive ability from aerosolized toxin.

“Ambush Predator”

3HABs-

water, or that kill without toxins by physicallydamaging gills or by creating low oxygenconditions (Figure 4). Pfiesteria and relatedtoxic species produce as yet unidentifiedtoxins that have been implicated in tempo-rary short-term losses of neurocognitiveabilities (short-term memory) in Marylandresidents exposed to water or aerosol con-taining the organism. Large, prolongedblooms alter the distribution of light, leadingto decreasing densities of valuable sub-merged aquatic vegetation in our coastal ar-eas and degradingnursery habitats.Dense accumulationsof some HABs alsolead to local depres-sions in oxygen levels(hypoxia and anoxia)that can reduce fishand shellfish habitat(e.g., seagrass, coraland sponge) and inmost severe condi-tions, kill endemic fishand shellfish commu-nities (Figure 4). OtherHAB species candamage local shellfishand aquaculture fishstocks, resulting in se-vere economic hard-ship and, in somecases, collapse of thefishery (e.g., Long Is-

land bay scallops).

What are the trends and economicconsequences of HABs?

Documented episodes of PSP human in-toxication and mortalities on the West Coastextend back to 1903 in California. PSP eventswere also common off Alaska, Oregon, Wash-ington, and Alaska, but extended into PugetSound only recently. On the East Coast, how-ever, observations of PSP events prior to 1972were limited to eastern Maine. Now, PSP hasspread throughout the rest of New England andto Georges Bank. As far back as the mid-16

th

century, NSP toxins, which poison human con-sumers of shellfish, have caused respiratoryirritation in humans and mortalities in fish andother wildlife in western Florida and Texascoastal waters, and occasionally were carriedby the Gulf Stream to North Carolina. For thefirst time, Mississippi, Alabama, and Louisianasuffered an NSP outbreak in 1996. ASP tox-

ins, which cause per-manent loss of short-term memory and insome cases death, nowoccur along the WestCoast and off Alaska,but the organism re-sponsible for toxin pro-duction has also beenidentified from northernGulf of Mexico and Mas-sachusetts waters.Ciguatera poisoning isthe most prevalent HABintoxication in tropicaland subtropical U.S.possessions, affectingas much as 50% of theU.S. Virgin Islandspopulation, as well asmany residents andtourists of other tropicalU.S. states and territo-

Figure 4. Dense algal blooms may consume oxygen in thewater column and cause massive mortalities of marine life.

PSP syndrome is life-threatening and canresult in respiratory arrest within 24 hoursof consuming shellfish laced with toxins

from feeding on algae in the genus Alexandrium.There is no antidote. PSP health risks are controlledby monitoring shellfish and rapidly closing toxic re-gions. PSP toxins can be transferred through thefood chain, killing fish, birds, and marine mam-mals.10-12 Before 1972, PSP on the U.S. Atlanticcoast was restricted to eastern Maine. Now theentire New England coastline experiences periodicPSP outbreaks with extensive shellfish bed clo-sures and economic losses. Similarly, PSP ap-peared in Puget Sound in the late 1970’s. PSP im-pacts more U.S. coastline than any other HAB.13

Paralytic Shellfish Poisoning

PSP events during last 10 years6-10 times2-5 times1 timeSampled but not detected

HABs- 4

ries.14 On this evidence, the experts concludethat HAB problems are increasing through-out U.S. coastal waters (Figure 5).

The scale of HAB economic impacts isstartling, and, if the trend continues, the fu-ture most likely holds economic hardshipsfor many more local communities that de-pend on healthy fish and shellfish resources.The rapid geographic expansion in the pasttwo decades is responsible for economiclosses approximating $100 million per year.This estimate would significantly increase ifshellfisheries that have never opened dueto continuous toxin accumulation were in-cluded in computations. For example, PSPin shellfish along Alaska’s 30,000 mile coast-

line has prevented developmentof a commercial shellfishery inthe state, estimated at $50 mil-lion annually.15 Domoic acid in-toxication of razor clams andDungeness crabs in Washingtonand Oregon resulted in lossesof $15-20 million in 1991, asso-ciated with collapse of the rec-reational and commercial fisher-ies and a huge tourist industry.Farmed fish have also been im-pacted as a result of mortalitiescaused by Chaetocerosconvolutus and Heterosigmacarterae, with 1987 losses of$0.5 and $4-5 million, respec-tively.16, 17

Along these same lines, asingle PSP event in Maine in1980 reportedly cost the state $7million18 and outbreaks have re-curred nearly every year since.Similarly, the bay scallop fisheryin Long Island, yielding $2 mil-lion annually, has never recov-ered from blooms of the browntide organism Aureococcus in1985.19 Pfiesteria events in Au-gust, 1997 along Maryland’s

Eastern Shore resulted in an estimated $40million loss in commercial sales for theChesapeake region.20 In the Gulf of Mexicoand along the western coast of Florida, G.breve blooms nearly every year, with esti-mated losses of $20 million per event.21 Incoastal North Carolina, 400 km of shellfisharea were closed from the same organismat a loss of $25 million in 1987-8822 and theshellfisheries of four states along the north-ern Gulf of Mexico (Florida, Alabama, Mis-sissippi and Louisiana) were closed in 1996,exceeding $15 million in lost revenue.23

Noneconomic losses accompanyingU.S. HAB events have also been dramatic.For example, 149 manatees, an endangered

NSPPSPFish killsCiguatera

Occasional anoxia

Pre-1972

NSPPSPFish kills

CiguateraBrown tideASP

Occasional anoxiaDSP (scattered, unconfirmed)Atlantic dolphin mortalities?Whale mortalities (PSP in mackeral)Florida Manatee mortalitiesNoxious blooms (aesthetics)

Post-1972

HIPR

HIPR

Figure 5. Since 1972, U.S. HAB distribution appears to be expanding andevents occurring more commonly.

* Shellfish Poisoning Syndromes: Neurologic (NSP),Paralytic (PSP), Amnesic (ASP), Diarrhetic (DSP)

**

*

*

5HABs-

species, were killed in off western Floridain a 1996 G. breve bloom. Each year,fish, bottlenose dolphins, whales, seaturtles and birds succumb from encoun-ters with U.S. HABs (Figure 6). Suchevents often trigger public outcry and a de-mand for immediate remedial action.

What causes HABs to increase?

Although few would argue that the num-ber of toxic blooms, the economic lossesfrom them, the types of resources affected,and the number of toxins and toxic specieshave all increased dramatically in recentyears in the U.S. and around the world, opin-ions differ with respect to the reasons forthis expansion.24-26 We may have contrib-uted to the global HAB expansion by trans-porting toxic species in ship ballast water27

or by dramatically in-creasing aquacultureactivities. Other “new”bloom events may re-flect indigenous popu-lations that were dis-covered because ofbetter detection meth-ods and more observ-ers.29 The linkage topollution, however,cannot be ignored. In-creased nutrient loadsto coastal waters maystimulate background(i.e., relatively lowlevel) populations ofmicroscopic and mac-roscopic algae to ini-tiate a bloom. Somescientists even arguethat the nutrients thathumans supply tocoastal waters are de-livered in proportionsthat differ from natu-

rally occurring ratios, such that we may be al-tering algal species composition by favoring cer-tain groups (e.g., HABs) better adapted to al-tered nutrient supply ratios.30 Pfiesteria, for ex-ample, seems to thrive in polluted waters.31

A U.S. INTERAGENCY HAB PROGRAM

Until recently, the U.S. had no national pro-gram or plan to attackproblems associatedwith HABs and marinebiotoxins, despite a longhistory of impacts, re-search, and local moni-toring. Research pro-grams were small, frag-mented, and uncoordi-nated, run by individualinvestigators and rarelyhave been sustainedthrough time. There waslittle communication be-tween workers and nofederal coordination ofactivities with respect tonational priorities. Incontrast, other countriessuch as Canada,France, and Japan es-tablished coordinatednational research pro-grams that included fre-quent meetings of inves-tigators, sustained fund-

Figure 6. Losses of wildlife from ingestion of HAB toxins aresignificant and include this dead pelican and these manatees.

NSP gastrointestinal and neurological symptomsfrom eating shellfish that have fed on toxicGymnodinium breve dinoflagellates, can be debili-tating.22, 28 There is no antidote; full recovery usu-ally is within days. Monitoring programs generallyprevent human exposure except in previously un-affected areas where officials may not be monitor-ing. During blooms, humans may be driven fromcoastal areas by asthma-like symptoms from rot-ting fish and toxic aerosols. Blooms occur annu-ally along Gulf of Mexico shores (e.g., 22 of thelast 23 years off western Florida), can cover asmuch as 3x104 km,2 and can last as long as 18months. In 1996, Louisiana, Mississippi, and Ala-bama experienced their first bloom—30 bottlenosedolphins were killed and the oyster industry suf-fered extensive economic loss. A 1997 Texasbloom killed over 14 million fish. Blooms are occa-sionally carried to North Carolina coastal waters.

Neurotoxic Shellfish Poisoning

NSP events during last 10 years6-10 times2-5 times1 timeSampled but not detected

HABs- 6

ing in high priority areas, and continual re-evaluation of progress and priorities for thefuture. This situation has begun to change inthe U.S. If the effort is sustained, elementsof a national program on HABs are beingimplemented at a scale that will surely havea significant impact on understanding thesephenomena and our ability to manage theirimpacts.

How has the U.S. responded to HAB events?

Agency and academic research labora-tories have been active for the past severalyears, primarily focusing on HAB effects onfish habitat and nutrition. This research gen-erated a substantial expertise and knowledgefor the diverse suite of HAB species in theU.S., but there was no coordinated approachto developing explanations for HAB problemsnationwide.

Convinced that HAB prevalences andimpacts were increasing, U.S. researchers,agency representatives, and members of theprivate sector began a series of workshopsat the start of this decade to plan a nationalresponse. Intense and productive workshopsover the last 5 years yielded a compre-hensive national HAB program outlined inthree separate reports. The first, a generalapproach to HABs outlined in the Departmentof Commerce’s National Oceanic andAtmospheric Administration (DOC/NOAA)sponsored report Marine biotoxins andharmful algae: A national plan32 is the nation’sfoundation for HAB research, management,and policy.

The second report—ECOHAB The ecol-ogy and oceanography of harmful algalblooms a national research agenda14—issponsored by the NOAA and the NationalScience Foundation (NSF). It is a focusedexpansion of National Plan objectives per-taining to the ecology, physiology and ocean-ography of bloom-forming species. This re-port is now the blueprint for ECOHAB, the

first Federal research program on the ecol-ogy and oceanography of HABs. ECOHABis supported by DOC/NOAA, NSF, the U.S.Environmental Protection Agency (EPA), De-partment of Defense’s Office of Naval Re-search (ONR), National Aeronautics andSpace Administration (NASA), and the U.S.Department of Agriculture (USDA). ECOHABresearch, focused on the mechanisms re-sponsible for HABs in U.S. coastal waters,will be used to develop predictive models forHAB events. Such models will help guidefuture regional and national agency re-sponses to protect citizens, businesses, andcoastal living resources from HABs.

The third portion of the U.S. HAB pro-gram is summarized in a report that focuseson processes, mechanisms, and technolo-gies that might be employed in the control ofHABs and their impacts. NOAA and the Na-tional Fish and Wildlife Foundation supporteddevelopment of Harmful algal blooms incoastal waters: Options for prevention, con-trol and mitigation.13 It too was derived from

ASP, so named because one of its most severesymptoms is the permanent loss of short-termmemory, can be fatal. The ASP toxin, domoic acid,is produced by the diatoms, Pseudo-nitzschiamultiseries and P. australis. First identified in east-ern Canada in 1987,3 it has been a problem for theU.S. Pacific coast states since 1991.33 Domoic acidhas been detected in shellfish on the east coast aswell and toxic P. multiseries cells have been iso-lated from Gulf of Mexico water. Besides shellfish,it is now known that domoic acid also accumulatesin fish and in crab viscera.

Amnesic Shellfish Poisoning

ASP events during last 10 years6-10 times2-5 times1 timeSampled but not detected

7HABs-

objectives of the National Plan but definesan area that the U.S. had not yet dealt effec-tively with in its responses to HABs (i.e., man-agement and control). The U.S. is far behindmany parts of the world in managing coastalwaters to limit HAB impacts. For example,Japan, China, and Korea are exploring a suiteof technologies and strategies (e.g., clay floc-culation, algicidal bacteria) to directly elimi-nate blooms in their territorial waters.36 Thisreport is now the basis of a new U.S. initia-tive to manage bloom development, persis-tence, and toxicity, thereby minimizing eco-nomic and ecologic impacts.

These three reports are the U.S. frame-work for an integrated national HAB program.Guidance, direction, and support for the U.S.program is provided in biannual meetings of

the Ad Hoc Interagency Task Force on Ma-rine Biotoxins and Harmful Algae, composedof agency representatives and academic re-searchers. Although individual Federal agen-cies maintain agency-specific HAB projects,NOAA’s Coastal Ocean Program (COP) istaking the lead in guiding initial portions ofthe national effort through coordination of theU.S. research program ECOHAB and is at-tempting to identify and interface HAB activi-ties across the agencies. In its infancy, thisactivity is receiving support from all agencieswith initial cooperation and dialog evidentamong the ECOHAB partners, the Depart-ment of Interior’s U.S. Geological Survey(USGS), as well as the agencies responsiblefor public health and seafood safety, the Foodand Drug Administration (FDA), the NationalInstitute of Environmental Health Sciences(NIEHS), and the Center for Disease Controland Protection (CDCP) in Human Health Ser-vices.

Additional input to the national programis also ensured through operation of the Na-tional Office of Marine Biotoxins and HarmfulAlgal Blooms, located in Woods Hole, Mas-sachusetts. This office, supported by NOAAand NSF, was established in response to anational need for timely HAB information andcoordination. The office distributes nationaland international HAB information to re-searchers, managers, and public officialsthrough its active web site. Further, the officeassists the national effort by overseeing na-tional workshops and symposia on HAB-re-lated topics. Overseen by Dr. Donald Ander-son, a HAB research scientist and U.S. rep-resentative to many international organiza-tions, the National Office is critical to contin-ued HAB activities nationwide.

How effective are current HAB efforts?

Research on toxins, toxic species, newdetection methods. Current research is fo-cused on some of the most troublesome HAB

CFP is a malady associated with dinoflagellate tox-ins that accumulated in tropical fish flesh. Althoughthe most frequently reported non-bacterial illnessassociated with eating fish in the U.S. and its terri-tories, the number of CFP cases is probably farhigher, because there is no confirmatory labora-tory test and reporting to the U.S. Center for Dis-ease Control is voluntary.28 CFP is produced pri-marily by epiphytic dinoflagellates (e.g.,Gambierdiscus toxicus, Amphidinium carterae,Coolia monotis and several others in the generaProrocentrum, Ostreopsis and Thecadinum) grow-ing on the surfaces of red and brown macroalgaein virtually all sub-tropical to tropical U.S. waters.When macroalgae are grazed by herbivorous fish,ciguatera precursors in the epiphytes arebiotransformed into ciguatoxin in fish flesh.Ciguatoxin accumulates, persists over extendedperiods and, if consumed by humans, causes long-term, debilitating, but non-lethal illness.34, 35

Ciguatera Fish Poisoning

g g

CFP events during last 10 years6-10 times2-5 times1 timeSampled but not detected

Puerto Rico

HABs- 8

species impacting coastal areas (Appendix1). The initial interagency ECOHAB projectsare in place and funded beginning in the fallof 1997. Two intensive, five-year multi-disci-plinary research programs are supported fortoxic Alexandrium in the Gulf of Maine andGymnodinium in the Gulf of Mexico, yieldingpredictive models for forecasting landfall ofthe HAB species. Seven other targeted stud-ies are also supported, addressing macro-algal blooms in Guam, trophic impacts of sev-eral U.S. HAB species (Alexandrium, Gyro-dinium, Prorocentrum, Pseudo-nitzschia),population genetics of brown tide populationsfrom Long Island, bacterial control of toxicGymnodinium, andnutrient require-ments of ASP-pro-ducing Pseudo-nitzschia. A secondfunding opportunityfor new research onPfiesteria and otherHABs was publishedthis spring withawards scheduled forthis summer. Bloomsof brown tide popula-tions that have deci-mated bay scallopsand seagrasses inLong Island are beingintensively examinedthrough a Brown TideResearch Initiative(BTRI), supported byNOAA’s COP. TheNOAA Sea GrantProgram is support-ing individual HABprojects throughoutthe U.S. that includetoxic species such asPfiesteria, Alexan-drium, and Proro-centrum.

Pfiesteria’s toxins are being intensivelyinvestigated through NOAA and NIEHS sup-port of the Charleston Laboratory and theUniversity of Miami’s Marine and Freshwa-ter Biomedical Science Center. Identification,purification, and assay development are im-minent. FDA is conducting research on theculture of pfiesterioid organisms for charac-terization, toxin production, and developmentof detection methods. Nutrient requirementsand trophic impacts of Pfiesteria-related spe-cies are part of an intramural research pro-gram at NOAA’s Beaufort Laboratory. Thelinkages between proliferation of coastalHABs with land use and watershed charac-

teristics are key com-ponents of intramuralEPA, USDA, andUSGS research pro-grams. The economicimpacts of HABs, acritical indicator of so-cietal influences on theinitiation of HABevents, are beingsummarized by theNational Office of Ma-rine Biotoxins andHarmful Algal Bloomswith support fromNOAA Sea Grant. Epi-demiology, symptomo-logy, diagnoses, ther-apy, and advisory in-formation for humansexposed to marinebiotoxins are major ini-tiatives within theCDCP. And finally, de-velopment of toxinbiomarkers, indicators,and exposure thresh-olds are expandingprograms within theCDCP and NIEHS.

National Plan ob-

BTBs, caused by golden-brown algae, recently ap-peared off southern New England and Texas. A mas-sive bloom of Aureococcus anophagefferens was firstreported in the bays of eastern Long Island, New York,in June of 1985. Severe brown tides have occurredin most years since then and now are also in BarnegatBay, New Jersey, and Narragansett Bay, Rhode Is-land. After a drought that increased the salinity andsevere freezes that killed millions of finfish in LagunaMadre, TX, an extensive bloom of a new species,Aureoumbra lagunensis, appeared in 1990 and eachsummer since. Both BTBs have had substantial eco-logical impacts (e.g., reductions in zooplankton graz-ing rates, decreased light penetration and reductionsin the extent of seagrass beds). Submerged aquaticvegetation has been decimated in both regions dueto BTB shading. Subtle ecosystem changes fromlong-term dominance of the Laguna Madre systemin southern Texas are likely.37 BTBs have causedmass mortalities of blue mussels in Rhode Island.38

In Long Island Sound, BTBs have had a severe im-pact on commercially valuable shellfish, affectingmore than 80% of New York’s bay scallop harvest.39

Brown Tide Blooms

9HABs-

jectives specific totoxin identification,characterization,human health, andassay developmentare current activitiesof CDCP, NIEHS,and laboratories inNOAA and the FDA.The NIEHS Marineand Freshwater Bio-medical ScienceCenters have dedi-cated missions formarine biotoxin re-search within eachuniversity center inthe NIEHS programreceiving annualsupport. The Uni-versity of MiamiNIEHS Marine andFreshwater Bio-medical SciencesCenter is an interna-tionally respectedresource for several toxins, including thebrevetoxins, fatal to endangered manateesand sea turtles. The Center’s staff is cur-rently focusing on identification of and as-say development for Pfiesteria toxins.NOAA’s Charleston Laboratory and theNorthwest Fisheries Science Center are in-vestigating toxin production and living re-source indicators to toxin exposure for sev-eral U.S. HAB species. NOAA’s NationalEnvironmental Satellite and Data Informa-tion Service (NESDIS) is purchasing, pro-cessing, and providing ocean color satellitedata and products in near-real time thatshould be helpful in detecting and monitor-ing HABs. In cooperation with COP, NESDISis currently developing regionally specificocean color algorithms and calibrating/vali-dating incoming and outgoing data streamsfor HAB detection (e.g., G. breve for the west

Florida shelf andAlexandrium for the Gulfof Maine).

CDCP and NIEHSwere active partners inresolving public healthissues for Maryland in1997. Through such ef-forts, CDCP-state part-nerships expand epide-miological studies onmarine biotoxins anddevelop case histories,diagnoses, therapies,and advisory informationfor public officials andthe health community.

Because of its man-date to ensure foodsafety, FDA maintains astrong research and re-sponse capability to de-tect, evaluate, and miti-gate toxic events whichcould affect food. FDAresearch on seafood tox-

ins (freshwater and marine) is carried out atdedicated seafood laboratories located inWashington, D.C., Dauphin Island, Alabama,and Bothell, Washington. These laboratoriesculture toxic organisms, isolate, and charac-terize toxins, develop methods, supply toxinstandards, and evaluate risks from toxin ex-posure. When outbreaks occur, these labora-tories analyze samples from cases of sus-pected seafood poisoning. Illnesses from shell-fish toxins (PSP and NSP) and ciguatera havebeen confirmed from several poisonings overthe past two years. FDA laboratories aid stateswhen emergency needs for environmentalanalyses arise that exceed state capabilities(e.g., the Gulf of Mexico NSP outbreaks of1996). FDA experts in seafood toxins work withstate and federal officials to determine the ex-tent and hazard from environmental occur-rences of familiar (e.g., PSP) or less familiar

Excessive growths of Anabaena, Aphanizomenon,and Microcystis, can lead to HCBs that exhibit se-vere neuro-, cyto- and hepatotoxicity in a variety ofmammals (e.g., humans and farm animals), birds,fish and invertebrates (e.g., zooplankton). HCBs arenational economic and environmental threats, occur-ring in large estuarine systems (e.g., ChesapeakeBay, Albemarle-Pamlico Sound and Florida Bay) andthe Great Lakes. For example, a persistent algalbloom dominated by a new HCB species,Synechococcus elongatus, appeared in 1991 in mid-north central Florida Bay, spread to central and west-ern areas, and persists more or less to this day. ThisHCB and the turbid waters and reduced light pen-etration it causes have been implicated in large-scalemortalities of seagrass and sponge beds and evendegradation of Florida Keys coral reefs.

Harmful Cyanobacterial Blooms

HABs- 10

toxic events (e.g., the response to the sus-pected Pfiesteria species events in Marylandlast year). A major undertaking of the FDAWashington Seafood Laboratory is the train-ing of state and foreign officials to establishobserver programs which provide early warn-ing of potential HAB events. FDA toxin ex-perts represent the U.S. in several interna-tional organizations (e.g., APEC, the AsianPacific Economic Cooperative) with goals forthe global distribution of safe seafood.

Monitoring and assessment capabili-ties. Other current HAB activities in the Fed-eral government address the National Planobjectives focusing on rapid response andassessment capabilities to toxic and HABoutbreaks. The unprecedented mass mortali-ties of fish, high incidence of fish with lesions,and public illness associated with toxicPfiesteria-like populations in Maryland’sEastern Shore tributaries this past summerinitiated an immediate Federal-state partner-ship to vigorously monitor and assess wa-

tershed conditions, public health, and sea-food safety for the region. An immediateNOAA and EPA allocation of funds resultedin an enhanced and expanded water qualitymonitoring program by Maryland’s Depart-ment of Natural Resources with cell identifi-cation and toxicity determined at North Caro-lina State University (Figure 7) and FloridaMarine Research Institute laboratories. ANOAA vessel and captain were stationed onthe river for the summer. The NOAA-StateCooperative Oxford Laboratory and USGSwere instrumental in assessing pathology oflesioned and dead fish as well as coordinat-ing fish bioassays in the Pocomoke River.CDCP and NIEHS assisted Maryland’shealth teams in conducting public health sur-veys and clinical examinations of Pfiesteria-exposed and non-exposed individuals.NIEHS, USDA, NOAA’s Sea Grant, and EPAsupported workshops specific to Pfiesteria,its toxins, and impacts. The FDA immediatelyinitiated short-term bioassays of Pfiesteria-exposed fish and shellfish to safeguard sea-food from the area. NOAA’s Maryland SeaGrant office produced a web site for near real-time distribution of information from the tribu-taries, laboratories, and public officials.

This immediate, multi-agency response,admittedly ad hoc, served to consolidate sup-port from individual agencies that a rapid re-sponse capability was a national need forcomparable events in the future and becameone of the primary recommendations for aninteragency report to the White House pro-viding recommendations for future HAB pro-grams in the U.S. Seven agencies (Depart-ment of Interior [DOI], DOC/NOAA, CDCP,FDA, USDA, EPA, and NIEHS) participatedto produce National harmful algal bloom re-search and monitoring strategy: An initial fo-cus on Pfiesteria, fish lesions, fish kills, andpublic health, providing the basis for plan-ning Federal activities and responses forsimilar events in the future. National Plan ob-jectives are focused and, with little revision,

DSP is considered by some scientists to be the mostcommon and globally widespread phytoplankton-related seafood illness. DSP-producing species ofphytoplankton such as Dinophysis acuminata andProrocentrum lima occur throughout all temperatecoastal waters of the U.S. The first confirmed inci-dence of DSP in North America occurred in 1990and 1992 in Canada. DSP, attributable to P. lima,has been reported from northern Maine and fromGeorges Bank, but generally is not a problem inthe U.S.

Diarrhetic Shellfish Poisoning

11HABs-

were the model for developing this HABStrategy.

The successes of the Federal-Statepartnership in rapidly responding toMaryland’s Pfiesteria-induced fish kills andpublic illnesses have also resulted in addi-tional support in FY98 to ensure a similarcapability in the coming year. NOAA andEPA each received funding for assistingState programs for Pfiesteria monitoringand assessment beginning this spring. Fol-lowing a meeting with mid- and south At-lantic state representatives, Federal-Statepartnerships will be formed through distri-bution of Federal funds to individual statesfor supplemental program assistance andthe expansion of selected program ele-ments.

Access to databases and informa-tion communication . The identification ofdatabases on bloom incidences, toxin oc-currence in shellfish, mass mortality events,epidemiology, and the dissemination of thisinformation is a key National Plan objec-tive. As noted above, the National Office ofMarine Biotoxins and Harmful Algal Bloomshas a HAB-dedicated web site for distribu-tion of all national and international HABmaterial. Most Federal agencies also main-tain web sites for distributing agency-spe-cific information and in the last severalyears, electronic linkages to HAB webpages have been a focus of several Fed-eral organizations. For example, NOAA’s

Maryland, North Carolina and Virginia SeaGrant Offices encouraged the public to usetheir HAB web sites and provided additionaladvisory information during the recentPfiesteria outbreaks. These Sea Grant Officesas well as others in Mississippi and New Yorkhave featured newsletters dedicated to HABsto inform the research communities and edu-cate the public on HAB threats in local regions.NIEHS Centers also distribute results throughweb sites. Further, community participation inHAB workshops is also increasing, largelythrough NOAA, NIEHS, USDA, NSF, and EPAsupport. The same agencies are identifyingHAB-related databases, another National Planobjective, for community access and revision.

Future HAB activity support . Congres-sional appropriations in FY 1998 and thePresident’s proposal for 1999 will strengthenand enhance critical capabilities to providecomprehensive research, monitoring, assess-ment, planning, as well as scientific and tech-nical support to states and communities (Fig-ure 7). One of the greatest threats to U.S.coastal areas—nonpoint source pollution, in-

Catastrophic losses of cultured and wild fish not only

occur from many toxic algal species, but also from

others that do not cause illnesses in humans. Blooms

of the diatom, Chaetoceros convolutus, do not pro-

duce a toxin but have caused massive fish kills.

Chains of these cells armed with long setae and short

secondary spines become lodged in fish gills and

cause blood hypoxia as a result of mucous produc-

tion. Blooms of the flagellate, Heterosigma carterae,

have caused even more extensive farmed-fish mor-

talities in British Columbia and Washington state with

substantial economic losses for this industry.

HAB Fish Kills

Figure 7. This North Carolina State University researcher isone of a few HAB scientists studying toxic Pfiesteria cells.

HABs- 12

National Plan Objectives NOAA CDC FDA E P A N S F NIEHS USDA DOI1. Isolate, characterize toxins—FY1998 400K 500K 400K 400K 300K FY 1999 resources 400K 500K 400K 250K 300K 200K2. HAB detection methods—FY 1998 300K 1500K 400K 400K 150K 32K 100K FY 1998 resources 300K 1500K 300K 400K 150K 300K 300K3. Toxin effects on ecosystems/humans—FY 1998 700K 5000K 700K 650K 120K 350K 40K FY 1999 resources 1700K 5000K 700K 950K 350K 500K4. Forecasting capabilities—FY 1998 2200K 400K 300K 682K FY1999 resources 3400K 400K 500K 572K5. Management and mitigation—FY 1998 500K 700K 700K FY 1999 resources 1000K 700K 500K 1000K6. Rapid response to HABs—FY 1998 500K 2000K 700K 800K 100K FY 1999 resources 2200K 2000K 700K 100K7. Communication, outreach, education—FY 1998 300K 1000K 500K 2K FY 1999 resources 300K 1000K 500K 10K8. Databases—FY 1998 400K 400K 100K 100K FY 1999 resources 800K 400K 100K 100K

TOTAL FY 1998 5 . 3 0 M 1 0 . 0 0 M 4 . 2 0 M 3 . 5 2 M 1 . 0 5 M 0 . 6 5 M 0 . 7 2 M 0 . 3 0 MTOTAL FY 1999 1 0 . 1 0 M 1 0 . 0 0 M 4 . 2 0 M 2 . 6 1 M 0 . 8 2 M 0 . 6 5 M 2 . 0 0 M 0 . 5 0 M

creasingly frequent outbreaks of harmful al-gal blooms, and other symptoms of degradedcoastal ecosystems that adversely impactcoastal economies—will be efficiently and ef-fectively addressed. Agency partners willcontinue participating in the multiagency Na-tional Pfiesteria Research and MonitoringStrategy and ECOHAB, as well as providegrants to states, universities, and communi-ties to conduct monitoring and rapid assess-ments in response to Pfiesteria and otherHAB outbreaks.

What is the future for a U.S. Inter-agency HAB Program?

Although this summary of current activi-ties suggests that the U.S. has a strong andactive national HAB program, the programis just beginning. Commitment to multi-agency coordination of HAB activities by in-dividual agencies has occurred only duringthe last five years, after each realized thatno single agency possessed either the fundsor expertise to respond to the suite of HABneeds. The initial partnerships among NOAAline offices for publication of the National Planhave since expanded to 3-agency sponsor-

ship of ECOHAB research projects, then 7agencies helped draft the National Strategyin response to the recent Pfiesteria crisis.With such interagency commitment, an inte-grated, interagency Algal Bloom Programmay become a reality in the near future.

With the goal of developing a predictivemodeling capability for HABs in all U.S.coastal waters (i.e., HAB predictions likecoastal weather forecasts), ECOHAB re-search must rigorously investigate and thenmodel growth and toxin dynamics of the 7-8toxic species and regions along the entireU.S. coast. Five-year ECOHAB researchprojects have just begun on two toxic spe-cies and regions, Alexandrium in the Gulf ofMaine and Gymnodinium in the Gulf ofMexico. The remainder of the coastline andother HAB species need investigation. Re-search is needed on brown tide populationsin Long Island Sound and off Texas, Pfiesteriain mid- and south Atlantic states, macroalgalblooms in Florida’s and Hawaii’s coral reefs,ciguatera dinoflagellates in sub-tropical andtropical U.S. possessions, Pseudo-nitzschiain the northwestern Gulf of Mexico and alongthe west coast, and Chaetoceros andHeterosigma in the northwest. These effortswill be the focus of future ECOHAB research

Federal FY 98-99 Support for U.S. HAB Activities

Table 1. Federal agency FY 1998 funding and proposed FY 1999 support for harmful algal bloom research,monitoring and assessment activities in U.S. coastal waters.

13HABs-

activities.A critical area in need of major support

that was identified in the National Plan andthe recent National Strategy for Pfiesteria isbetter understanding of toxin impacts, bothacute and chronic, on coastal resources andhumans. This includes identification of thetoxins and toxic cells in water and tissues;development of rapid, reliable, and inexpen-sive assays for their field detection; identifi-cation of biomarkers for monitoring HAB tox-ins in wildlife and humans; and establishmentof exposure thresholds for toxicity. Addition-ally, development of the medical expertisespecific to toxins, toxicology, and treatmentshould be addressed. Although some of thiseffort is already underway at the NIEHS Cen-ters for research, the CDCP, a USGS labo-ratory, an FDA laboratory, and two NOAAlaboratories, an expanded intra- and extra-mural program is needed to gain baselineinformation quickly on such complex topics.

Reducing HAB impacts is a major em-phasis for the emerging national HAB pro-gram. The National Plan objective to pursueprevention, control and mitigation options forour increasing HAB problem is a criticalneed. As HABs continue to increase, wemust refocus our goals and research exper-tise toward developing techniques for detect-

ing and ameliorating the impacts of these natu-ral disasters (Figure 8).

Finally, there are strong indications thathuman activities in watersheds of coastal tribu-taries may be directly linked to the increasingprevalence and impacts of several HAB spe-cies. This implies that coastal eutrophication(excess nutrient loads), increased frequencyof HAB events, and reduced oxygen levels inwater (e.g., hypoxia and anoxia in the “deadzone” in the Gulf of Mexico) may all be inter-related. There has been an increasing empha-sis and coordination among DOC/NOAA, EPA,USDA, and DOI to enhance research capaci-ties in these areas. This comprehensive na-tional approach to nutrient inputs and coastalecosystem responses resulted in a major fo-cus of the recent Clean Water Action Plan be-ing the reduction of excess nutrients fromnonpoint sources of pollution, particularly incoastal areas.

SUMMARY

The U.S. has in place a national HAB pro-gram arising from the framework provided bythe three focused HAB reports prepared dur-ing the past five years. These reports are thebasis for 1) the integrated, multi-agency na-tional research program, ECOHAB, 2) a fo-cused partnership between CDCP and NIEHSto significantly expand our capacity to respondto human health concerns from marinebiotoxins produced by coastal HABs, and 3)a developing interagency HAB managementprogram. The Federal government has initi-ated a rapid assessment capability to assiststates and regions impacted by unexpectedHAB outbreaks. Attention to linkages betweenhuman activities on the land and bloom out-breaks in receiving waters is a renewed focusfor several agencies (i.e., DOC/NOAA, EPA,USDA, and DOI). The U.S. HAB science com-munity is vigorously responding to the needfor toxin and HAB detection methods to pro-vide field assays for most of our algal toxins

Figure 8. Enhanced color satellite imagery is one ofseveral tools being refined to detect and track HABs.

HABs- 14

in the near future. Safe seafood for our soci-ety is ensured through the continuous toxinmonitoring and bioassay operations coordi-nated by the FDA.

Although much remains to be done thereis a firm base provided by our national ex-pertise and technologies. The future is full ofnew challenges in HAB research, monitor-ing, assessment, and prediction. The Fed-eral agencies are committed to sustainingtheir national effort to ensure healthy livingresources, seafood safety, and sustainedeconomic development in regions impactedby HABs.

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2. Burkholder, J.M., E.J. Noga, C.H. Hobbs,and H.B. Glasgow Jr. 1992. New “phan-tom” dinoflagellate is the causative agentof major estuarine fish kills. Nature358:407-410.

3. Burkholder, J.M., H.B. Glasgow, Jr., andK.A. Steidinger. 1995. Stage transforma-tions in the complex life cycle of anicthyotoxic “ambush-predator” di-noflagellate, pp. 567-572. In: P. Lassus,G. Arzul, E. Erard-LeDenn, P. Genlien,and C. Marcaillou-LeBaut (eds.). Harm-ful Marine Algal Blooms, Lavoisier, Inter-cept, Ltd.

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8. Anderson, D.M. and P.S. Lobel. 1987.The continuing enigma of ciguatera. Biol.Bull. 172:89-107.

9. Geraci, J.R., D.M. Anderson, R.J.Timperi, D.J. St. Aubin, G.A. Early, J.H.Prescott, and C.A. Mayo. 1989. Hump-back whales (Megaptera novaeangliae)fatally poisoned by dinoflagellate toxin.Canad. J. Fish. and Aquat. Sci 46: 1895-1898.

10. Anderson, D.M. and A.W. White. 1992.Marine biotoxins at the top of the foodchain. Oceans 35:55-61.

11. Shumway, S.E. 1995. Phycotoxin-relatedshellfish poisoning: Bivalve molluscs arenot the only vectors. Reviews in Fisher-ies Science 3:1-31.

12. Shumway, S.E., S. Sherman-Caswelland J.W. Hurst. (1988). Paralytic Shell-fish Poisoning in Maine: Monitoring amonster. J. Shellfish Res. 7:643-652.

13. Boesch, D.F., D.M. Anderson, R.A.Horner, S.E. Shumway, P.A. Testor, andT.E. Whitledge. 1997. Harmful AlgalBlooms in Coastal Waters: Options forPrevention, Control and Mitigation.NOAA Coastal Ocean Program DecisionAnalysis Series No. 10. NOAA CoastalOcean Office, Silver Spring, MD. 46 pp.

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+ appendix.14. Anderson, D.M. (ed.). 1995. ECOHAB,

The Ecology and Oceanography ofHarmful Algal Blooms: A National Re-search Agenda. Woods Hole Oceano-graphic Institution, Woods Hole MA. 66pp.

15. Nevé, R.A. and P.B. Reichardt. 1984.Alaska’s shellfish industry, pp. 53-58 .In: E.P. Ragelis (ed.), Seafood Toxins.Amer. Chem. Soc. Symp. Ser. Wash-ington, D.C.

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17. Horner, R.A., J.R. Postel, and J.E.Rensel. 1991. Noxious phytoplanktonblooms and marine salmon culture inPuget Sound, Washington. In: J.R.Forbes (ed.), Pacific Coast Researchon Toxic Marine Algae. Canadian Tech-nical Report on Hydrographic OceanScience 135:59-61.

18. Shumway, S.E. 1988. A review of theeffects of algal blooms on shellfish andaquaculture. Journal of the WorldAquaculture Society 21:65-104.

19. Kahn, J. and M. Rochel. 1988. Mea-suring the economic effects of browntides. Journal of Shellfish Research7:677-682.

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21. Habas, E.J. and C.K. Gilbert. 1974. Theeconomic effects of the 1971 Floridared tide and the damage it presagesfor future occurrences. EnvironmentalLetters 6: 139-147.

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and red tides: a global perspective, In: RedTides: Biology Environmental Science andToxicology, edited by T. Okaichi, D. M.Anderson and T. Nemoto, pp. 11-16,Elsevier, New York.

25. Smayda, T.J. 1990. Novel and nuisancephytoplankton blooms in the sea: evidencefor a global epidemic, pp. 29-40. In: E.Granéli, B. Sundstrom, L. Edler, and D.M.Anderson (eds.) Toxic Marine Phytoplank-ton. Elsevier.

26. Hallegraeff, G.M. 1993. A review of harm-ful algal blooms and their apparent globalincrease. Phycologia 32:79-99

27. Hallegraeff, G.M. and C.J. Bolch. 1992.Transport of diatom and dinoflagellate rest-ing spores via ship’s ballast water: impli-cations for plankton biogeography andaquaculture. J. Plankton Res. 14:1067-1084.

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29. Anderson, D.M., Kulis, D.M., Doucette,G.J., Gallagher, J.C., Balech, E. 1994. Bio-geography of toxic dinoflagellates in thegenus Alexandrium from the northeasternUnited States and Canada. Marine Biol-ogy 120:467-478.

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In: D. M. Anderson, A.D. Cembella, andG. M. Hallegraeff (eds.). PhysiologicalEcology of Harmful Algal Blooms.Springer-Verlag, Heidelberg.

32. Anderson, D.M., S.B. Galloway, and J.D.Joseph. 1993. Marine Biotoxins andHarmful Algae: A National Plan. WoodsHole Oceanographic Institution Techni-cal Report WHOI-93-02, NMFS andNOAA COP, Woods Hole, MA. 44 pp. 29.

33. Garrison D.L., S.M. Conrad, P.P. Eilers,and E.M. Waldron. 1992. Confirmation ofdomoic acid production by Pseudo-nitzschia australis (Bacillariophyceae)cultures. J. Phycol. 28:604-607.

34. Ragelis, E.P. 1984. Ciguatera seafoodpoisoning: overview, pp. 25-36. In: E.P.Ragelis (ed.). Seafood Toxins, Amer.Chem. Soc. Symp. Ser. No. 262, Wash-ington, D.C..

35. Juranovic, L. R. and D. L. Park. 1991.Foodborne toxins of marine origin:ciguatera. Rev. Environ. Toxicol. 117: 51-94.

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37. Buskey, I.J., S. Stewart, J. Peterson, andC. Collumb. 1996. Effects of a persistent“brown tide” on zooplankton populationsin the Laguna Madre of south Texas, pp.659-666. In: T.J. Smayda and Y. Shimizu(eds.). Toxic Phytoplankton Blooms in theSea. Elsevier, Amsterdam.

38. Sieburth, J.McN., P.W. Johnson & P.E.Hargraves. 1988. Ultrastructure and ecol-ogy of Aureococcus anophageffe-rensgen. et sp. nov. (Chrysophyceae): thedominant picoplankter during a bloom inNarragansett Bay. J. Phycol. 24:416-425.

39. Cosper, E.M., W.C. Dennison, E.J. Car-penter, V.M. Bricelj, J.G. Mitchell, andS.H. Kuenstner. 1987. Recurrent andpersistent brown tide blooms perturbcoastal marine ecosystem. Estuaries10:284-290.

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marine phytoplankton, zooplankton graz-ers, and pelagic food webs. Limnologyand Oceanography 42(5):1203-1214.

APPENDIX 1

Federal HAB-related Projects/Pro-grams . Numerous projects/programs relatedto HABs are underway in Federal offices andlaboratories; descriptions of primary HAB ef-forts follow.

DOC/NOAACoastal Ocean Program (COP) is co-

ordinating the competitive, federal, inter-agency research program, ECOHAB, imple-mented to determine environmental factorsand cellular mechanisms responsible forHAB events in U.S. coastal waters. This part-nership of DOC/NOAA, NSF, EPA, USDA andONR, is focused on identification of thosefactors favoring growth and accumulation ofHAB species in order to develop predictivemodels for forecasting bloom events.ECOHAB’s multi-disciplinary, long-termprojects link circulation of specific systemswith the ecophysiol-ogy of individual taxa,yielding a biophysicaldescription of bloomformation, terminationand toxicology. Pres-ently, two regionalblooms are being ex-amined (Gulf ofMaine and the Gulf ofMexico), leaving ap-proximately two-thirdsof the U.S. coastlineand the associated al-gal blooms to be ad-dressed in future ECOHAB projects. COP,in partnership with EPA, also drafted the Na-tional Strategy. Further, COP sponsored thecomprehensive report on prevention, controland mitigation of HABs, developed this Con-gressional report, and provides financial sup-

Figure 9. The basis for a U.S.HAB coastal research program.

17HABs-

port for the National HAB Office and the In-ternational Oceanographic Commission’s(IOC) HA News (an international newsletteron HABs). COP represents the U.S. on theIOC Intergovernmental Panel on Harmful Al-gal Blooms and the APEC Marine ResourceConservation Working Group, and activelyworks in establishing bilateral HAB agree-ments with its international partners.

Sea Grant Program . With its role inmarine research, education, advisory ser-vices and public outreach, Sea Grant exper-tise and its network of local experts plays amajor role during HAB events. Sea Grant haslong supported individual investigators study-ing local HAB problems (e.g., research firstidentifying Pfiesteria in North Carolina) andthis support has built the foundation for sev-eral of the large regional HAB field projects.A series of articles recently published byMaryland Sea Grant (e.g., In Harm’s Way?The Threat of Toxic Algae; Harmful AlgalBlooms on the Move; and The Trouble withToxics in the Bay) explained to readers thelatest information on algal blooms, particu-larly those in the Chesapeake Bay region andthe role of the complex of Pfiesteria-like or-ganisms in fish mortalities in the PocomokeRiver. Sea Grant programs in Maine, Mas-sachusetts, New York, Florida, Texas, Wash-ington, North Carolina, and Alaska have re-leased similar materials on HABs from thoseareas of the country. Sea Grant workshopsin Maryland and North Carolina on Pfiesteriaproblems were instrumental in easing publicconcerns over the threat from this harmfuldinoflagellate.

NOAA laboratories (at Charleston,Beaufort, Oxford, Great Lakes, and Seattle)conduct research on coastal HABs and theirimpacts. Charleston’s HAB research focuseson structural chemistry, biochemistry, toxicol-ogy and phycology of PSP, NSP, ASP, DSP,ciguatera and Pfiesteria toxins. Highlights in-clude toxin purification and methods for de-tecting toxins in seafood and environmental

samples (e.g., cell-based receptor and re-porter gene assays), and research on mo-lecular mechanisms controlling growth in di-noflagellates, therole of bacteria inbloom dynamicsand toxin produc-tion and effects ofalgal toxins on re-productive healthof fisheries spe-cies. Beaufort, withexpertise in cultur-ing toxic phytoplankton and assessing theramifications of biotoxins in marine foodwebs,40 has been actively involved in G.breve research since 1987 and nowPfiesteria. Highlights include a new tech-nique for brevetoxin determination (sensitivecapillary electrophoresis with laser detec-tion), a feasibility study on the use of phy-toplankton pigments and absorption spectraas potential biomarkers for G. breve, calibrat-ing data and calculating algorithms for theSea WiFS ocean-color satellite sensor formonitoring HABs. Oxford Lab is a center ofexpertise for invertebrate pathology and ma-rine fish diseases with numerous publications(e.g., a Manual on Histologic Techniques, astandard for processing fish and shellfish,and the Registry of Marine Pathology cata-loguing fish diseases. Oxford Lab has beenmonitoring and studying the recent outbreakof fish lesions and mortalities in ChesapeakeBay. The Great Lakes Environmental Re-search Laboratory (GLERL) conducts re-search on the status and causes of eutrophi-cation, which can lead to HABs in coastalecosystems, and the recent occurrence ofHABs in the Great Lakes. Highlights includelong-term nutrient dynamics and modelingstudies on key Great Lakes ecosystems andvideo documentation of zebra mussel abilityto selectively feed on nontoxic algal cellswhile rejecting toxic HAB cells. GLERL in-vestigators participate in HAB-related re-

Figure 10. NOAA’s CharlestonLaboratory scientist identifies HABs.

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search in the Gulf of Mexico (e.g., nutrientinputs to the Gulf of Mexico from the Missis-sippi outflow and the relationship to hypoxia)and are also involved in the ECOHAB: Floridaproject in the Gulf of Mexico (e.g., determin-ing the autecology of G. breve). NorthwestFisheries Science Center biotoxin researchis focused and integrates methodology, foodweb interactions, species susceptibility andcoastal ecosystem health. Recent highlightsinclude development of new receptor bind-ings and DNA probes for toxin and toxic al-gae detection, studies of toxin transferthrough the food web, and culture studies todetermine effects of nutrients on toxin pro-duction.

EPAU.S. Environmental Protection

Agency’s (EPA) Office of Research andDevelopment (ORD) is presently cooperat-ing with NOAA and others in supporting re-search concerning toxic algal blooms as oneof the cosponsors of the ECOHAB Program.

Further, EPA has beenNOAA’s primary partner in re-sponding to recent WhiteHouse and Congressional re-quests for HAB activities, ex-emplified by the EPA/NOAApartnership in allocating$500,000 in the summer of1997 for rapid response tofish lesions and mortalities,and public health concernslinked to Pfiesteria in theChesapeake. Further, EPAand NOAA led the effort to

draft the National Strategy and distributeFY98 funds for State monitoring and assess-ment programs for HABs. In 1997, EPA alsoprovided funds to North Carolina to estab-lish a rapid response team. Additionally,EPA’s Environmental Monitoring and Assess-ment Program (EMAP) and NOAA’s NationalStatus and Trends Program have developedand tested appropriate methods to charac-

terize the condition of the Nation’s resources,including those related to HABs.

The National Health and Environmental Ef-fects Research Laboratory (NHEERL) GulfEcology Division (GED) has recently estab-lished a new multidisciplinary HAB researchteam with objectives for FY98 that include 1)establishing a state-of-the-art HAB Experi-mental Culture Exposure Facility and 2) de-veloping rapid response and monitoring ca-pabilities for HAB events in the Gulf ofMexico. The HAB team will collaborate withthe GED’s Coastal Eutrophication Team tobetter define and understand the suggestedcausative link between increased nutrientloading and HAB phenomena. Recently, aHarmful Algal Bloom page was added to theGulf of Mexico Aquatic Mortality ResponseNetwork (GMNET) at http://pelican.gmpo.gov/gmnet/gmhome.html). Finally, GED isworking to obtain funding for a proposedstudy of HAB formation and transport in theGulf of Mexico.

ORD will be involved in assessing the pos-sible adverse effects of specific toxins onlaboratory rodents and to evaluate the neu-rological effects of Pfiesteria toxins on NorthCarolina watermen. ORD also proposes toconduct studies to assess the efficacy of itsscreening methodologies in evaluating thepotential neurotoxicity to HAB toxins toaquatic animals.

EPA’s Office of Water . Many of the pro-grams in the Office of Water address non-point sources of pollution that have been im-plicated as causes for many HAB events. TheNational Estuary Program (NEP) includes 28estuaries around the country. All 28 estuar-ies have characterized nutrient over-enrich-ment problems and several have identifiedHABs as priority concerns. In fact, theAlbemarle-Pamlico Sound Estuary Programwas the site of the discovery of Pfiesteria.EPA’s National Nutrient Strategy is beingcompleted to strengthen our ability to assessand control nutrient over-enrichment in the

Figure 11. EMAP scientists testwater quality in U.S. estuaries.

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nation’s waters. This strategy summarizes thedirection the EPA recommends with respectto developing water quality criteria to addressover-enrichment problems. Concentrated Ani-mal Feeding Operations (CAFO) is an EPAregulatory program whose aim is to ensurethat discharges from large feeding operationshave National Pollutant Discharge Elimina-tion System (NPDES) permits. It is anticipatedthat the program will support the developmentand promotion of improved methods to dis-pose of animal waste.

The Total Maximum Daily Load (TMDL)program addresses waterbodies listed byStates as impaired and for which pollutioncontrols are not stringent enough to achievewater quality standards applicable to suchwaters. Under the TMDL program we canidentify which rivers or estuaries are listed bythe States as impaired due to nutrients orother HAB indicators and whether a TMDLhas been established to adequately reducethe nutrient loadings from all sources. TheTri-chemical Action Plan includes several re-cent and pending air regulations which willreduce air emissions (and deposition) of vari-ous forms of nitrogen as well as propose ad-ditional actions that should be taken to fur-ther reduce nitrogen loadings from air emis-sions, other nonpoint sources, and wastewa-ter discharges. Under the Clean Water Act§319 Nonpoint Source Management Pro-grams, EPA provides funding, guidance andtechnical assistance to States in their effortsto minimize nutrients, from nonpoint sources.Beaches Environmental Assessment Closureand Health (B.E.A.C.H.) is an initiative to im-prove the safety of recreational waters in theU.S. through improved public right to knowabout the quality of swimming waters; devel-opment of appropriate warning systems andimproved monitoring strategies for fresh wa-ter and marine/estuarine beach scenarios.

NSFNational Science Foundation (NSF) is

concerned with developing basic scientific un-

derstanding of the direct and indirect causesof HABs and their ecological consequencesthrough research on the physiological andecological basis of bloom formation, thephysical and chemical attributes of coastaloceans that facilitatethem, the populationattributes of bloomspecies, and thelong-term conse-quences of ecosys-tem changes. NSFcosponsored the re-port ECOHAB Theecology and ocean-ography of harmfulalgal blooms a na-tional researchagenda and contin-ues to cooperate withNOAA by providingfunding for the ECOHAB Program throughthe NSF Division of Ocean Sciences, Bio-logical Oceanography Program. The Biologi-cal Oceanography Program also supportsother HAB-related research as part of itsregular research program. In addition, theNSF Division of Biological Infrastructure andthe Biological Oceanography provide supportfor the Provasoli-Guillard National Center forCulture of Marine Phytoplankton (CCMP), arepository for phytoplankton cultures includ-ing HAB species.

DOD-ONROffice of Naval Research (ONR) sup-

ports research related to the mission of theU.S. Navy and to develop improved under-standing of the environment (e.g., opticalproperties of surface waters) in which theNavy must operate. As part of this research,ONR has been cooperating with NOAA andothers in providing support for the ECOHABProgram.

NASA National Aeronautics and Space Ad-

ministration (NASA) has recently become

Figure 12. The National Plan isthe basis for a U.S. HAB program.

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an advisor to ECOHAB because of its strongcommitment and interest to remote detec-tion of surface pigment, as found in someHABs. With the successful orbiting and op-eration of SeaWifs and long-term commit-ment to determining surface distributions ofphytoplankton biomass and productivity inspace and time, NASA’s partnership is timelyand beneficial to the national HAB effort.

DOI-USGSU.S. Geological Survey (USGS) , as part

of its contribution to the Chesapeake BayProgram, is conducting field sampling, labo-ratory analyses and building a GeographicalInformation System data base on the rela-tionship between nutrient inputs in the wa-tershed and Chesapeake Bay water quality.USGS’s Biological Resources Division hasbegun investigations to determine factorscontributing to fish lesions (e.g., the complexof Pfiestera-like organisms) in selected tribu-taries of the Chesapeake Bay. Scientists fromthe USGS Center for Marine and Coastal Ge-ology in Woods Hole, MA, are actively in-volved in the ECOHAB-Gulf of Maine re-gional study, providing mooring equipmentand expertise, and developing coupled physi-cal/biological models of Alexandrium dynam-ics in the large region between the Cana-dian border and Massachusetts.

HHS-CDCCenters for Disease Control and

Prevention (CDC) , as the Nation’s diseaseprevention agency, has a monitoring,advisory and public communication roleregarding human health concerns andharmful algal blooms. As an example, CDCrecently collaborated with officials from statehealth departments (i.e., Delaware, Florida,Georgia, Maryland, North Carolina, SouthCarolina, West Virginia, Virginia and theDistrict of Columbia) and held a September1997 Workshop on the Public HealthResponse to Pfiesteria. The CDC broughttogether representatives of state healthdepartments and the relevant federal

agencies (e.g.,Food and DrugAdministrat ion,National Instituteof EnvironmentalHealth Sciences,U.S. Environmen-tal ProtectionAgency) with the goal of planning acoordinated, comprehensive multi-statepublic health program to provide scientificallyvalid information on health effects ofPfiesteria exposure. The recentCongressional allocation of $10 million willprovide funds necessary for state-specificsurveys to be implemented and compiled fordetailing symptoms of HAB exposures.

NIH-NIEHSNational Institute of Environmental

Health Sciences (NIEHS) addressespotential human health impacts of Pfiesteriaand other HABs through response, research,and prevention. NIEHS responded immedi-ately to the public health threat posed byPfiesteria by assisting state healthdepartments in their efforts to address thisproblem and by enabling scientists tointeract more effectively. NIEHS researchincludes both basic studies to identify andcharacterize relevant toxins and theirassociated biological effects as well asclinical and epidemiological research todefine more accurately exposure and healtheffects. NIEHS prevention efforts includesupport of assay development for improvedidentification and early detection andmonitoring of the organism and toxin.

In August 1997, NIEHS received arequest from Senators Mikulski andSarbanes to help investigate fish kills in thePocomoke River of southeastern Maryland.Representatives from NIEHS and CDC,visited the a workshop on “HazardousMarine/Freshwater Microbes and Toxins,”where researchers, regulators, federalrepresentatives, and state health and

Figure 13. This CDC scientist is iso-lating HAB toxins in human tissues.

21HABs-

environmental officials met and discussedtheir current understanding of a variety ofhazardous toxins. This workshop was thefirst that enabled Pfiesteria and othermarine toxin researchers to meet,exchange information, and identifyresearch gaps.

As part of its Center Program, NIEHSsupports a network of Marine and Fresh-water Biomedical Sciences (MFBS) Cen-ters across the country. Two of these areactive in the area of Pfiesteria and HABresearch. The University of Miami MFBSCenter, long noted for its work in marinetoxins, is engaged in isolating and charac-terizing Pfiesteria toxins. The Duke Univer-sity MFBS Center has focused on under-standing possible biological effects arisingfrom exposure to Pfiesteria-laden waters.

The NIEHS intramural program hasprovided assistance to scientists from NorthCarolina State University, NOAA NationalMarine Fisheries Service in Charleston,South Carolina, and NIEHS to collaborateon isolating Pfiesteria toxin.

To stimulate prevention research,NIEHS recently awarded $400,000 to aconsortium composed of leading investiga-tors in both basic and clinical research re-lated to Pfiesteria. This award will bringtogether researchers at the NIEHS MFBSCenter at the University of Miami, headedby Dan Baden, Ph.D., and at the Univer-sity of Maryland School of Medicine,headed by Glenn Morris, M.D., M.P.H., toexamine the potential public health impactof this organism collaboratively. This projectplans to purify and characterize toxins, ex-

amine theireffects inmodel sys-tems, de-velop a ge-netic assayfor identifica-tion and de-

tection of Pfiesteria, obtain information on riskfactors and exposure levels for human healtheffects, and clarify putative neurologic effects.This multidisciplinary approach is an inte-grated effort to examine systematically the keyresearch questions that must be answered inorder to improve our understanding of boththe environmental and public health conse-quences of Pfiesteria. Results from this andrelated research will lead to development ofdiagnostic, therapeutic, and preventative strat-egies.

FDAFood and Drug Administration (FDA) is

responsible for ensuring safe seafood for con-sumption and, therefore, has well-establishedprograms of research, management, and pub-lic information regarding HABs as they relateto toxicity in seafood. There are ongoing re-search programs dealing with PSP, NSP, ASP,DSP, and ciguatera. Prior to 1997, the possi-bility that Pfiesteria had seafood safety impli-cations was being addressed by closely fol-lowing research being done in other laborato-ries. With the dramatic intensification of thisissue, research has been started in-house withcollaboration from other laboratories to clarifywhether or not toxins from Pfiesteria can ac-cumulate in seafood and cause illness in hu-man consumers. In general, FDA researchlaboratories culture toxic marine organisms,then isolate and characterize the toxins theyproduce. With a continuing supply of the tox-ins thus assured, FDA labs develop detectionmethods for the toxins and examine their tox-icity to provide a basis for regulatory policy.FDA researchers also address the broader is-sue of effective management strategy, and arecurrently exploring the utility of networks of fieldobservers who take phytoplankton samplesand gather relevant environmental information.Such networks are now in place with FDA co-ordination in California, Maine, and Massachu-setts, and show great promise as a strategyfor reducing the cost and improving the reli-ability of marine biotoxin monitoring programs.

Figure 14. This NIEHS scientist centri-fuges HAB cells for toxicology studies.

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Figure 15. FDA-trained volunteerscheck plankton samples for HABs

The FDA supportsestablished monitor-ing programs world-wide through the pro-duction and distribu-tion of referencestandards, expert as-sistance, and qualityassurance checks oflaboratories. Marinebiotoxin monitoring in

the U.S. is conducted primarily through co-operative programs with the states under theguidance of the FDA. The FDA provides pub-lic information and education through its Sea-food Hotline telephone service, a web pagethat includes discussion of marine biotoxinissues, and tradition channels such as theprint media and public information special-ists.

USDAU.S. Department of Agriculture (USDA) .

The strong linkages between land-use, nu-trient loads and watershed conditions aremajor concerns for this agency (Figure 16)and have led to USDA’s advisory role inECOHAB. There is an intensive watershedassessment program, providing water qual-ity data critical for HAB prediction. Future ef-forts will identify agricultural activities likelyfavoring HAB expression, leading to applica-tion of best management practices (BMPs)for these critical activities.

NOPPNational Ocean Partnership Program

(NOPP). This congressionally mandated part-nership of 12 federal agencies promotes itsgoals of assuring national security, advanc-ing economic development, protecting qual-ity of life, and strengthening science educa-tion and communication through improvedknowledge of the ocean by coordinating andstrengthening partnerships among Federalagencies, academia, industry, and othermembers of the oceanographic scientific

community. Regarding HAB problems, NOPPrecently supported a 2-year project, Gulf ofMexico Ocean Monitoring System, to gener-ate continual surface ocean current veloci-ties in the Gulf. This effort, a collaborationbetween the Dynalysis Corporation, severalFederal agencies and the university researchcommunity, will generate critically neededsurface current distributions that are likely re-sponsible for distributing G. breve, a toxicHAB that has plagued local coastal re-sources, economies, and public health inFlorida and the northern Gulf States, alongthe coastline of the southern United States.

Figure 16. USDA scientists study land-use links to HABs andadvise farmers on nutrient abatement measures.