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Red Tide

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A "red tide" or "harmful algal bloom" is a natural event caused by rapid growth of microscopic, single-celled algae that makes the ocean looks red or brown, especially in summertime, and especially when rains wash more nutrients into rivers and the sea. Most kinds of algae are harmless plants but some types produce a natural toxin that can contaminate shellfish that eat the algae. Animals or humans who eat the contaminated shellfish can be poisoned. Local fishing areas are usually closed during major red tides to prevent harvest and sales of contaminated shellfish. Local fish advisories tell you when to avoid buying or eating shellfish.

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