Hundreds of sea turtles washing up dead on Southwest Florida beaches, likely victims of red tide

Desdemona Despair

By Chad Gillis
25 July 2018

(Fort Myers News-Press) – Hundreds of sea turtles have washed up on Southwest Florida beaches this year in a mass mortality event that researchers say will impact the recovery of protected species.

Seventeen have been recovered in Sanibel and Captiva waters in the past week.

“Our average for the entire year is usually around 30 or 35, but we’ve had 53 in June and July alone,” said Kelly Sloan, a sea turtle researcher at the Sanibel-Captiva Conservation Foundation on Sanibel.

Sloan said SCCF has picked up 91 sea turtles on the islands since the red tide bloom started in October.

“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.”

More than 100 turtles have been plucked from Sarasota County waters, and another 66 have been found in Collier.

“It’s really disheartening to see this mass mortality,” Sloan said. “This is the 10th month of the red tide event, and it’s the longest continued bloom since 2006.” […]

The organism that causes red tide here (Karenia brevis) occurs naturally, but many water quality scientists say the blooms last longer and are more intense due to human activities like farming and development.

Collier is seeing above-average numbers of sick and dead sea turtles as well.

“The last two days have been really bad with red tide, and we had two strandings today and two yesterday,” said Maura Kraus, a sea turtle expert for Collier County. “The red tide is in everything they eat, and they’re breathing it. The most vulnerable turtles are the Kemp’s ridleys and the loggerheads, and it’s concentrated in the food they eat.”

Kemps’ ridleys are one of the world’s most endangered sea turtles.  The loggerhead population here is listed as threatened under the Endangered Species Act. [more]

Hundreds of sea turtles washing up dead on SWFL beaches; red tide likely killer