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Dangerous Marine Organisms. Protistans and Invertebrates. Outline. Algae Sponges Cnidarians Mollusks. Algae: Red Tide. Red Tides occur in and around the US as well as other areas of the world
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Dangerous Marine Organisms Protistans and Invertebrates
Outline • Algae • Sponges • Cnidarians • Mollusks
Algae: Red Tide • Red Tides occur in and around the US as well as other areas of the world • Occasionally, the algae grow very fast or "bloom" and accumulate into dense, visible patches near the surface of the water. • These blooms often appear red in color • The term is a misnomer; nothing to do with tides
Algae are Protist • Simple plant – like organisms - autotrophs • Often single celled, but some are multi - cellular • Marine, freshwater and terrestrial • Dinoflagellates are often associated with blooms
Dinoflagellates http://images.search.yahoo.com/search/images/view?back=http%3a//images.search.yahoo.com/search/images%3fp=dinoflagellates%26ei=UTF-8%26cop=mss%26tab=3&h=391&w=450&imgurl=www.microscopy-uk.org.uk/mag/imgsep01/dino2.jpg&name=dino2.jpg&p=dinoflagellates&rurl=http://www.microscopy-uk.org.uk/mag/artsep01/dinof.html&type=&no=2&tt=935
Algae Life Cycle http://www.whoi.edu/redtide/whathabs/whathabs.html
HABs • HAB refers to bloom phenomenon that contain toxins or that cause negative impacts (Harmful Algae Blooms) • These toxins are neurotoxins and they may cause the death of fish, birds and even humans
Organisms Affected http://www.whoi.edu/redtide/foodweb/HABfoodweb.html
Shell We Do Lunch? 1990 six fisherman almost died after eating steamed mussels (Georges Bank)
Alexandrium • This “blooming” algae produces a neurotoxin • Clams, mussels and other filter feeders concentrate the toxin. • Toxin causes the paralysis of the diaphragm muscles….asphyxiation may result • Coast Guard air lifted the fisherman ashore • They were hospitalized, but recovered in a few days. Soon back fishing.
Fish Kills due to Harmful Algal Blooms Florida Beach Covered with Red Tide Killed Fish
Marine Mammals Die 1991 Cape Cod 14 Humpback Whales Die from Saxitoxins in Mackeral
Why Do HABs Occur? • No clear answer • Some evidence that pollution may cause HABs • Other studies indicate pollution not a major factor • Some hypothesize that increased monitoring of marine waters turns up cases that would otherwise be missed.
Ciguatera (CFP) - 1 • CFP produces gastrointestinal, neurological, and cardiovascular symptoms. Generally, diarrhea, vomiting, and abdominal pain occur initially, followed by neurological dysfunction including reversal of temperature sensation, muscular aches, dizziness, anxiety, sweating, and a numbness and tingling of the mouth and digits.
Ciguatera and Reef Fish • Ciguatera results from the eating of reef fish affected with ciguatoxin. Ciguatoxin originates from a dinoflagellate name Gambierdiscus toxicus which colonizes coral beds. The toxin first affects the coral-grazing fish and is then passed up and through the food chain to the piscivorous fish (i.e., snapper, grouper, amberjack, barracuda) and finally to man. The toxin is not affected by either cooking or freezing, and the affected fish, cooked or raw, is not tainted by bacteria in any way. Typically, the victim states, "It was the best fish I ever tasted."
Some History • Ciguatera symptoms were first described in the 1500's by the Spanish explorers to Cuba and were attributed to the ingestion of a small snail which they called cigua. • In the Pacific, the first Tahitian death on the ship Bounty (of the famous Mutiny on the Bounty) was the ship's surgeon after a fish feast: "Old Bacchus died not of drink, as might have been supposed, but of eating a poisonous fish.“ • http://www.rehablink.com/ciguatera/poison.htm
Ciguatera (CFP) - 2 • causative organisms: Gambierdiscus toxicus, Prorocentrum spp., Ostreopsis spp., Coolia monotis, Thecadinium sp. and Amphidinium carterae • toxins produced: Ciguatoxin/Maitotoxin • Avoid eating tropical reef fish • No cure • http://www.whoi.edu/redtide/illness/illness.html#Ciguatera%20Fish%20Poisoning
Fire Sponge Body Smooth, soft, with wide irregular lobes, few large pores; bright red or orange. Colonial; encrusts on rocks, corals, mangrove roots. Caution: causes severe rashes and blisters.Habitat Low-tide line to 50’ deep; bays, lagoons.Range Throughout region (Florida, Bahamas, and the Caribbean). . http://www.enature.com/fieldguide/showRguide.asp?rguideID=711&speciesID=4738
The Cnidaria • Jellyfish, corals and their relatives • Almost all species are marine • All contain stinging cells (nematocysts) • Very few species are" dangerous” • Two basic body forms: polyp and medusa
Australia's box jellyfish http://www.ucmp.berkeley.edu/cnidaria/cubozoa.html
Chironex fleckeri About 100 deaths during the past century Native to the marine system of Northern Australia Many have survived encounters with Chironex Death may result when stung by 6-8 meters of tentacles.
Portuguese Man-o’-war • Fatal Portuguese man-o'-war (Physalia physalis) envenomation.Stein MR, Marraccini JV, Rothschild NE, Burnett JW.Office of the Medical Examiner, West Palm Beach, Florida.A fatal case of Physalia physalis (Portuguese man-o'-war) envenomation occurred on the Florida Atlantic coast in 1987. Despite appropriate beachside first aid, the patient was conscious only several minutes before having primary respiratory arrest and, later, cardiovascular collapse that resulted in death. Discharged nematocysts were still visible on the injured stratum corneum five days after envenomation. Additional treatment maneuvers suggested by this case include testing the tentacle fragments found on the victim's skin before their removal to ensure that nematocyst firing has been counteracted. We document the first human fatality caused by P physalis envenomation.
Physalia Physalia in composed of a colony of polyps http://www.ibss.iuf.net/people/skryabin/neuston.html
Swimming Medusa Video • http://www.pbrc.hawaii.edu/bekesy/angel/video/alata.html Stinging Cell (nematocyst)
Mollusks • Clams, mussels, snails, octopi and their relatives • Marine, freshwater, and terrestrial species • Shelled, have “foot” for locomotion • Clams and mussels are filter feeders • Many snails are predacious • All octopi are predators
Cone Shell • Marine reef dwelling snails • Predators (fish, snails, and worms) • Toxic “harpoons” • Toxin has medicinal properties • The active components of the venom are small peptides toxins, typically 12-30 amino acid residues
Cone Shell Radular Apparatus Radula
Distribution • In the US: Cone shells are indigenous to US waters, but travelers are not likely to encounter them (Gulf of Mexico and Florida Keys) • Internationally: Thirty cases of human envenomation have been recorded from the Indo-Pacific region and Australia.
Envenomations “When envenomations occur in humans, usually to the hands or feet, the result is somewhat unpredictable. Minor envenomations cause pain, swelling, and localized numbness that often subsides within hours of onset. Serious envenomations are associated with a rapid progression of symptoms, including paralysis, respiratory arrest, cardiac failure, and death.” • http://www.emedicine.com/med/topic1636.htm
Xenome (Pharmaceutical Company) About Xen2174 • Xen2174 is a synthetic drug modeled on a peptide isolated from the venom of a cone shell found on Australia's Great Barrier Reef. • Xen2174 is currently under preclinical development for the management of chronic pain.
Blue Ringed Octopus http://www.earlham.edu/~sheedjo/blue-ringedoctopus.htm
Blue Ringed Octopus • Distributed from Japan to Australia • Common in tide pools and reefs • Small 200mm across • Very toxic (bite) • Tetrodotoxin (same as found in pufferfish and poison arrow frogs) • Neurotoxin…dumbness, paralysis, difficulty in breathing…may require ventilation
The Mystery of TTX • “It was a mystery why such a diversity of unrelated organisms would all evolve the same toxin, until it was recently discovered that bacteria associated with many of these animals actually produce TTX. This is the case in blue-ringed octopuses. Their salivary glands harbor dense colonies of TTX-producing bacteria. The blue-rings have evolved a symbiotic relationship with the bacteria….”” http://www.nhm.ac.uk/hosted_sites/tcp/bluering2.html