Sea turtles have recently washed ashore dead or suffering on Florida’s southwest beaches in numbers that are extremely concerning to the already endangered species.
According to experts, the number of stranded turtles is more than three times the average amount. “Our average for the entire year is usually around 30 or 35, but we’ve had 53 in June and July alone,” Kelly Sloan, a sea turtle researcher at the Sanibel-Captiva Conservation Foundation on Sanibel, told News-Press
Experts are pointing to longer-than-normal algae bloom as the culprit for the death of the turtles.
Researchers cannot say with absolute 100% certainty that it was the red tide that killed or injured the turtles, but Sloan said she is “very confident” that the turtles were claimed by the algae bloom because many exhibited neurological symptoms associated with red tide.
The bloom has varied in intensity and distribution, at times stretching from the Tampa Bay area to the Florida Keys.
“Most of them have been mature adults, and only 1 in 1,000 make it to adulthood,” Sloan said. “It takes a loggerhead 25 to 30 years to mature, so that really does have a significant impact on their recovery.”
The organism that causes red tide in southwest Florida occurs naturally, but due to known and fixable problems with water table drainage and more increased land usage for farming and development are the blooms are lasting longer.
According to the Centers for Disease Control and Prevention, a red tide occurs when toxic microscopic algae rapidly grow in the ocean, sometimes changing the seawater to a red, brown, yellow, or green color.
Red tide can kill fish, birds, marine mammals, and cause illness in humans. Over the last 10 months, the bloom has changed in intensity and distribution. Recent numbers indicate concentrations of 1 million cells per liter and higher, with major health issues starting when levels reach 10,000 cells per liter, according to the Florida Fish and Wildlife Conservation Commission.