While it looks like there are fewer spots of red tide dotting our coast, the effects of it can last much longer by taking a toll on wildlife.
The CROW Clinic on Sanibel Island has admitted nearly 100 royal terns (Thalasseus maximus) as patients so far this year.
Of those birds, 66 have signs of red tide poisoning, showing how algal blooms can disrupt the food web.
So, it’s a welcome sight when the CROW Clinic releases an animal back into the wild.
Executive director of the CROW Clinic, Alison Hussey, said, “If we can get them and treat them, and they survive their first 24 hours with us, our release rate doubles.”
Hussey said they’ve seen 97 royal terns so far this year. In all of 2020, they saw only 49. And more than half of those birds rescued this year have shown red tide symptoms.
“Neurologically when they’re affected, they don’t fear humans and they get a little discombobulated,” she explained. When that happens, some end up in dangerous places like the causeway.
And it’s not just birds.
Hussey added. “… Sea turtles, we’ve seen three from red tide effects. Unfortunately, two did not make it, but our loggerhead is still here with us and doing really well and responding to treatment.”
Researchers at the Sanibel-Captiva Conservation Foundation study what birds and turtles eat, from fish and crabs to seagrass.
Research Scientist Dr. Richard Bartleson, with the SCCF Marine Lab said, “We’re just looking at how long the toxins last in the food web.” Adding, in some cases, red tide toxins can linger for months.
In the past, he’s studied oysters and found once the bloom was gone, it took six months for the oysters to have low enough concentrations of toxins to be safe for people to eat.