red tide

The bioluminescent light is also produced by a dinoflagellate known as Pyrodinium bahamense (1a). Some dino's are also become parasites on fish. Half of the organisms that produce the red tide are dinoflagellates, but other groups from phytoplankton can cause the tide as well such as cyanobacteria, diatoms and chrysophytes (4). .
             All forms of marine life is greatly affected by the red tides, mainly the filter feeding shellfish such as oysters, clams, mussels and mollusks (4). These bivalves filter in the food and they also take in the deadly neurotoxins (5). It is difficult to tell what is good to eat and what is not. Shrimp, crab, scallops and lobsters are safe in the red tide to harvest and to eat, because they don't have the red tide toxin in their meaty or hard muscle tissue that we eat. The muscle or hard meat of the finfish is safe to eat, as long as the fish behave normally, but eating the liver, organs or any part of the soft tissue is not a good idea (9). The bivalves (oysters, clams, mollusks, mussels) are unsafe because they are filter feeders. The Department of Environmental Protection determines if the water is clear of the red tide or of the toxins that can harm both marine life and humans. It could take as long as 3 weeks for the water to clear up after a tidal bloom and even if it has been long enough, some of the filter feeders can hold on to the toxins for longer periods then that (9). Not only is the filter fish in harm when a red tide occurs, but the HAB's are responsible for the deaths of some endangered marine mammals such as the Florida manatee. In 1996, the red tide caused about 10% of the Florida manatee population and 162 dolphins in Mexico (7). If these mammals also eat the bivalves, such as marine birds, they can also have serious side effects and some could be fatal. .
             Human health is another impact of the red tide. About one third of red tide blooms produce some of the most toxic poisons found.