Scientists are studying new algae that have turned up in San Carlos Bay and Pine Island Sound off Sanibel Island. It’s similar to a toxic algae found off the coast of Australia. It’s called Lyngbia and it’s under investigation by researchers at the Sanibel Captiva Conversation Foundation. It first turned up in December and it still persists. Lab Manager Dr. Steve Bortone says there’s a possibility contact with it could cause a rash called swimmers itch – but so far no cases have been reported. He says the primary concern is the impact on sea grasses.

In this particular case they’ve become so abundant they’ve covered over the blades of sea grass – and why that’s a problem is that they interfere with the light the sea-grasses can get and it turns out that blue green algae and sea grass require the same kind of light so it’s literally stealing the light from the sea grass.

Swimmers itch has been reported in Australia – but Bortone says it’s not the same algae. He says growth of blue-green algae is promoted by high nutrient levels.

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A new form of algae is now flourishing off Sanibel in San Carlos Bay and Pine Island Sound. The blue-green algae cling to sea-grasses – blocking the sun. Lab Manager at the Sanibel Captiva Conservation Foundation, Steve Bortone, says the persistent bloom is the result of poor water quality.

it’s a accumulation of a lot of issues, some stuff coming out of the lake, there’s probably some additions from the municipalities there’s septic areas where septic tanks may be overflowing in some cases. It might even be decomposition of materials left behind by the hurricane and those are rotting and putting their nutrients into the system –

Blue-green algae in Australia are toxic and causes swimmers itch, but Bortone says this variety doesn’t appear to do that. What it does do is coat the stems of sea-grass – blocking sunlight, potentially killing the grasses and leading to further deterioration of water quality.