ANNA MARIA ISLAND – The bioluminescent glow coming off the water in recent nights may be related to the aftermath of Hurricane Idalia, according to one local expert.
“This could be related to the nutrient pulse from Idalia,” said Dr. Dave Tomasko, executive director of the Sarasota Bay Estuary Program. “The water came up and much of the grass clippings and yard debris on our landscape got dragged back out into the bay as the water receded. So our water took a little bit of a hit.”
Tomasko said there are several types of organisms that could be responsible for the glowing flashes in local waters.
“It seems most likely to be a dinoflagellate called gonyaulax,” he said. “That’s a type of single-cell organism that’s known to cause California red tide, but not here. Our red tide here is caused by a different organism.”
Another organism, noctiluka, which comes from the Latin meaning “shines by night,” could also possibly be the cause of the glow, Tomasko said.
Tomasko said the organisms are not harmful to humans.
“It’s thought that this lighting is a protection against predators,” he said.
“The neat thing about these organisms is they create light from an enzyme they have that takes chemical energy and turns it into light,” he said. “It has to be there in a high enough amount to see the glow. It’s a neat little show.”
The best time to see the phenomenon is when the sky is darkest, he said.
Tomasko said the bioluminescence has often been seen south of Coquina Beach in Longboat Pass.
“One way to stir them up is to kick at the water, or the waves from a boat will do it,” he said. “I would not advise swimming at night though.”
