Scientists are warning that a red tide is reemerging along the state’s southwest coast even after a recent cold front knocked it back.

Medium counts of red tide organism were recorded in Lee, Charlotte and Sarasota counties last week.

Rick Bartleson of the Sanibel-Captiva Conservation Foundation's says he found 700,000 cells per liter near a preserve west of Fort Myers, although he said he hasn't heard of any fish kills there.

The News-Press reports scientists have counted high levels of the algae linked to red tide in recent weeks along southwest Florida beaches.

Red tide organisms grow naturally in the Gulf of Mexico. But high concentrations are harmful to wildlife and can cause respiratory problems in humans, which were reported this week in the counties affected by the bloom.

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