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http://cmbc.ucsd.edu/People/Faculty_and_Researchers/chapman/. The original lecture “ Algae: The World’s Most Important ‘Plants’ ” Presented at the Birch Aquarium at Scripps is available at:. http://www.uctv.tv/search-details.asp?showID=11931. http://www.youtube.com/watch?v=CB2XlpD-Ld4.
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http://cmbc.ucsd.edu/People/Faculty_and_Researchers/chapman/ The original lecture “ Algae: The World’s Most Important ‘Plants’ ” Presented at the Birch Aquarium at Scripps is available at: http://www.uctv.tv/search-details.asp?showID=11931 http://www.youtube.com/watch?v=CB2XlpD-Ld4 http://www.oilgae.com/videos/watch/13/Algae--The-World-s-Most-Important-Plants/
Osher Lecture 4 – Harmful Algal Blooms (HABs) Red Tide (California) The world’s Most Important Plants Gone Awry?
Osher Lecture 4 – Harmful Algal Blooms (HABs) New Zealand The world’s Most Important Plants Gone Awry?
Osher Lecture 4 – Harmful Algal Blooms (HABs) Valparaiso, Chile ? The world’s Most Important Plants Gone Awry?
Harmful Algal Blooms (HABs) – what are they? They are harmful blooms of algae. Harmful in various ways… Blooms = massive amounts of algae in an area (large or small) What are massive amounts? Example: 1.2 x 107 cells per liter 12,000,000 cells per liter
What algae are involved in HABs? Mostly phytoplankton ≈ 300 spp. (but seaweeds too, c.f. China and the Olympics) Which phytoplankton? Mainly, but not soley, dinoflagellates and diatoms
* * Sandie Baldauf (University of York) 2009
What about the Red Tides? The Red Tides specifically dinoflagellate blooms and some are actually red in color, but not all Dinoflagellate blooms are red. The Red Tides are perhaps the best known HABs for various reasons.
Why are the blooms harmful? About ¼ of the 300 spp. produce toxins. What do the toxins do? 1) amnesic shellfish poisoning (ASP) 2) ciguatera fish poisoning (CFP) 3) diarrhetic shellfish poisoning (DSP) 4) neurotoxic shellfish poisoning (NSP) 5) paralytic shellfish poisoning (PSP) 1994. South Africa west coast (St. Helena Bay) hydrogen sulfide poisoning via Ceratium furca and Prorocentrum micans.
1) amnesic shellfish poisoning (ASP) Caused by domoic acid (accumulated in shellfish and boney fish) Effects: gastrological and neurological disorders incl. loss of memory and death Algae: diatoms – Pseudo-nitschia spp. Areas: Canada, West Coast of the USA
2) ciguatera fish poisoning (CFP) Caused by ciguatoxin and maitotoxin Effects: gastrointestinal, neurological, and cardiovascular disturbances (rarely death) Recovery: months or even years Algae: dinoflagellates – Gambierdiscus toxicus Area: the tropics
3) diarrhetic shellfish poisoning (DSP) Caused by okadaic acid Effects: diarrhea, nausea, cramps (no death) Algae: dinoflagellates – Dinophysis acuta & D. acuminata Areas: Spain, Mediterranean & Adriatic Seas, etc.
4) neurotoxic shellfish poisoning (NSP) Caused by brevitoxins (neurotoxins) & hemolytic toxins (colorless, odorless, heat-stable and acid-stable polyethers!!) Effects: via food: gastrointestinal & neurological disturbances; via air & volatilized toxin: respiratory problems (asthmas-like) Algae: Karenia brevis (aka Gymnodinium breve) Areas: Gulf of Mexico, now New Zealand etc.
5) paralytic shellfish poisoning (PSP) Caused by saxitoxin (a sodium channel blocker) Effects: nausea; vomiting; diarrhea; abdominal pain; tingling or burning lips, gums, tongue, face, neck, arms, legs, and toes; shortness of breath; dry mouth; aching feeling; confused or slurred speech; lack of coordination; and death (15% no known antidote) Algae: Alexandrium tamarense
5) paralytic shellfish poisoning (PSP) Caused by saxitoxin (a sodium channel blocker) Effects: nausea; vomiting; diarrhea; abdominal pain; tingling or burning lips, gums, tongue, face, neck, arms, legs, and toes; shortness of breath; dry mouth; aching feeling; confused or slurred speech; lack of coordination; and death (15% no known antidote) Algae: Alexandrium tamarense Areas: USA: northeast coast, Alaska, west coast; Asia, Europe, South America, etc.
The harm done by non-harmful algal blooms ? Monterey Bay 2007 – hundred of dead sea birds A red tide of Akashiwo sanguinea – a NON-toxic dino. Dead algae protein-rich foam = a surfactant ruined the waterproofing on the birds’ feathers they got wet & cold & died
HABs can be red rides but they can also be green tides, brown tides, black tides, etc. Brown Tide: Aureoumbra lagunensis
General points about HABs: Financial aspects: monitoring costs, commercial losses, human and animal welfare “costs” There are toxic and non-toxic strains of the same species. (Species-ID is often HARD !!!) There can be many “versions” of the toxins. The presence of bacteria complicates the toxin situation. Occurrences are often not predictable. HABs: more frequent, more severe, more places… HABs: more scarry (cf., Pfiesteria)
Be afraid… Be very afraid! Be good… Be very good and take care of the planet!