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Harmful Algal Blooms. By Jill M. Worner. What are Harmful Algal Blooms ?. Single celled marine plants called phytoplankton. Most species are not harmful and serve as the energy producers at the base of the food web.
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Harmful Algal Blooms By Jill M. Worner
What are Harmful Algal Blooms ? • Single celled marine plants called phytoplankton. • Most species are not harmful and serve as the energy producers at the base of the food web. • Phytoplankton become harmful when they occur in an unnaturally high abundance, they produce a toxin, or contain physical attributes (i.e. spines). • “Bloom” – accumulate into dense, visible patches near the surface of the water. • Initiated by right set of environmental conditions.
Group 1 • Certain cyanobacteria, diatoms, and macroalgae. • Harmless species. • However, when they occur in dense blooms creates anoxic conditions. • Causes fish and invertebrate kills.
Group 2 • Toxic cyanobacteria and dinoflagellates. • Produce potent toxins. • Causes illness or death in grazers which continues up the food chain due to the effects of bioaccumulation.
Group 3 • Certain diatoms, dinoflagellates, and raphidophytes. • Species are not toxic. • Contain physical attributes such as spines. • Causes irritation • Damages gills and tissue.
What Can Be Done? • Satellite remote sensing imagery used to follow HABs and record distribution data . • As technological advances increase, information could be used to: • warn coastal communities allowing for a more efficient fish clean up. • Identifiy shellfish beds that may have been affected. • Learn more about toxins to better treat sick people.
Positive Results from HABs • Nature’s way of balancing itself. • Populations get too large – fish are killed. • Removal of weak species. • Other populations increase: • Fishermen reported higher catches of crabs and other animals following a bloom.