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afrol News, 15 February - South African marine expert Dr Grant Pitcher has successfully isolated and identified the killer organism, probably responsible for the deaths of thousands of fish and hundreds of other ocean dwellers off the Eastern Africa shoreline. The culprit is a notorious fish-killing algae that produces lethal neuro-toxins, and is well known to many fisheries world-wide. It belongs to the Gymnodinium species - recently renamed Karenia mikimotoi. This algae has astounded local fishing communities and conservationists by its ability to kill an extremely wide variety of ocean creatures ranging from reef fish such as red snapper, porcupine fish, trigger fish, parrot fish, sturgeon fish and moray eels, according to the conservation organisation WWF. It also killed sailfish, octopus, sharks, marlin and manta rays as well as sea snails and turtles in the Kenya-Somalia waters. WWF staff and local fishers monitoring the unusual event saw dead fish that were laterally flattened, their eyes popping out and discoloured in appearance. - I do not think that we have to look much further than the Gymnodinium species presence in the samples, as the cause of fish mortalities off the Kenyan and Somalia coastline, said Dr Grant Pitcher, a marine and coastal management expert based in Cape Town, South Africa. According to the Kenya Marine Fisheries Research Institute, only fish were affected in previous die-off in southern Kenya, whereas this event seems to be much larger, killing the entire range of the region's sea creatures. Dolphins too seem to have been affected, being washed ashore ten days after the peak of the red tide. One was found dead badly blistered as if it had been burned, with deep cuts in its rapidly decomposing flesh. It was not possible to confirm whether Gymnodinium algae were the killer in this case. Other reports indicate that, at the same time, similar events have taken place in Omani and Yemeni waters also sparking concerns, while South Africa is reported to just have begun experiencing what is being termed as its worst "red tide" ever. A "red tide" is defined as an explosion of microscopic toxic algae that colour ocean waters reddish brown. Scientists are however still puzzled by the unusual occurrence of an algal bloom in the prevailing rough water conditions. "Red tides" normally occur when ocean surface waters are warm, calm and high in nutrients. The good news however is that the fishing ban on everything but filter feeders such as oysters, whelks and mussels has been lifted in Kenya and the fishing communities are back in business.
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