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Harmful Algal Blooms (HABs)

A harmful algal bloom (HAB), also known as a red tide, is the proliferation of toxic nuisance algae that cause a negative impact to natural resources or humans. Currently 85 toxic microalgal species have been documented; of these, 37 live in Gulf of Mexico waters.

Because they have chlorophyll and are capable of photosynthesis, most of the algal bloom species can be classified as plant-like. They require light, nutrients and carbon dioxide to produce their own food using chlorophyll. There are a few species that do not have their own chlorophyll and thus cannot photosynthesize. These obligate or facultative heterotrophs are called protists, not microalgae.

Recently, there has been a noticeable increase in problems associated with HAB's. Impacts of these natural phenomena include human illness (or death) from contaminated seafood, marine mammal and seabird deaths and extensive fish kills.

This list of Web sites is just a small portion of the information that is available on this subject, use it as your gateway to the world of Harmful Algal Blooms. Please understand that the information on these sites has not been reviewed by the U.S. Environmental Protection Agency (EPA) or the Gulf of Mexico Program (GMP) for validity, nor do they necessarily express the views of the EPA or the GMP.

Harmful Algal Blooms

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Gulf States Marine Fisheries Commission's. Listing of Marine Toxic Bloom Events in the Gulf of Mexico.

Harmful Algal Bloom Information and Facts from Florida Fish and Wildlife Research Institution

The Harmful Algae Page. A Woods Hole Oceanographic Institute site providing good general information on all types of harmful algal blooms.

Harmful Algal Blooms. Website from the University of Maryland with information and explanations of types of harmful algal blooms.

Harmful Algal Blooms pages from NOAA's Center for Sponsored Coastal Ocean Research (CSCOR).

2004 EPA National Center for Environmental Research (NCER) Science to Achieve Results (STAR) Recipients for Ecology and Oceanography of Harmful Algal Blooms. Includes Abstracts.

The Intergovernmental Oceanographic Commission (IOC) Harmful Algal Bloom Programme webpages. Includes Harmful Algae News, an IOC newsletter on toxic algae and algal blooms, links to meeting sites, reports, databases, reference materials, and images.

Guide for the Control of Molluscan Shellfish. From the US Food and Drug Administration, National Shellfish Sanitation Program. A 2-part manual for the sanitation of shellfish growing areas, and for sanitation of the harvesting,
processing and distribution of shellfish.

Compendium of Fish and Fishery Product Processes, Hazards, and Controls from the National Seafood HACCP Alliance for Training and Education. An explanation of natural seafood toxins by the University of Southern California Davis, including preventative measures and analytical procedures.

Harmful Algal Blooms and Toxins. A brief general discussion of the problem, causes, and context, from SeaWeb.

Harmful Algal Blooms Program. NOAA Northwest Fisheries Science Center Harmful Algal Blooms Program. A good discussion of HABs with illustrations and links to other pages.

GEOHAB, Global Ecology and Oceanography of Harmful Algal Blooms, a Joint SCOR-IOC Programme of International Co-operative Research on HABs in Marine and Brackish Waters.

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Red Tides

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Red Tide FAQs. A brief FAQ site provided by the State of Texas.

Red Tide Chronology. A brief chronology of red tide events along the southwest Florida coast.

Harmful Algal Blooms. Brief discussion of harmful algal blooms. Gives map showing major HAB-related event in U.S. coastal waters.

ECOHAB. A comprehensive site dealing with Gymnodinium breve Red Tides in Florida.

Solutions To Avoid Red Tide, Inc. A non-profit organization "dedicated to funding and promoting efforts to control red tide and keep it from our shores."

ABOUT RED TIDE. A general red tide discussion.

Toxic Red Tides and Harmful Algal Blooms. A comprehensive discussion of red tides and HABs by Woods Hole.

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Brown Tides (Aureococcus)

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Brown Tide Blooms. A University of Maryland site with general information on Brown Tides.

Sea Grant New York's Brown Tide Research Initiative

Organic nitrogen uptake by Aureococcus anophagefferens. The abstract of a paper on nitrogen uptake by Aureococcus anophagefferens during a Brown Tide event.

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General Links

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Introduction to the Dinoflagellata. A University of California, Berkley site with general information on dinoflagellates.

Dinoflagellates. A Canadian site with general discussion of dinoflagellates, including other links and references.

Other Phycological Collection Catalogs. A University of California Museum of Paleontology site list of links to other phycology sites.

UCMP Glossary. A University of California, multi-volume glossary of biological terms.

Ecology of Emiliania huxleyi. Discusses an ongoing study to determine the cause, or conditions that support, Emiliania huxleyi blooms.

Various Shellfish-Associated Toxins. An FDA site with information of algal toxins associated with shellfish.

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Gulf of Mexico Program Office
Mail Code: EPA/GMPO
Stennis Space Center, MS 39529-6000
228-688-3726
FAX: 228-688-2709


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