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SCCF observes spike in sea turtle strandings due to red tide

By Staff | Jul 25, 2018

PHOTO PROVIDED A stranded Kemp's ridley sea turtle.

Since the beginning of the current red tide bloom in October, 91 sea turtles have been found stranded on the beaches or in waters surrounding Sanibel and Captiva, the Sanibel-Captiva Conservation Foundation reported.

Of those, 58 were dead and 33 were found alive and taken to CROW for treatment.

The continuous 10-month red tide has impacted an unprecedented number of sea turtles. Over 50 have stranded on Sanibel and Captiva in June and July alone.

Of the 91 strandings since October, 53 have been mature adults, representing a significant impact on a recovering population of animals where only one in 1,000 hatchlings survive to reach reproductive maturity at around 25-30 years of age. Nineteen of them – nine which have washed up the third week in July – have been the critically endangered Kemp’s ridley sea turtle, a rare sighting on area beaches.

With help from the SCCF Marine Lab’s Dr. Rick Bartleson, SCCF is collecting samples of tissues and gut contents from stranded sea turtles to be tested for brevetoxins – neurotoxins produced by the alga Karenia brevis. Since May 29, 24 turtles have been sampled in an effort to understand how the algal blooms affect sea turtles.


The current red tide causing this mass mortality event is the longest continuous bloom since 2006, when an algal bloom lasted over one year. The blooms start in the Gulf of Mexico, but are fed and perpetuated by high nutrients in the water washing into the Gulf from land, according to officials.

SCCF continued that the past eight years of regulations addressing water quality have been rolled back under the guise of making Florida business friendly. Current water conditions are the direct consequence of that effort. Ways to help out:

– Report disoriented or stranded sea turtles at 978-728-3663 (978-SAVE-ONE).

– Make water quality part of daily dialogue and this election year.

– Elevate the issue of water quality; ask candidates if they support stronger water quality standards and what specifically they will do to raise standards to clean water and represent the public’s interests.

– Examine own actions in fertilizer use in yards and gardens.

– Plant native landscapes to reduce/eliminate fertilizer use and enhance filtering of rainfall.

– Pick up after pets.

A few suggestions to address sources of nutrients:

– Require advanced wastewater treatment to remove nutrients from reuse water systems.

– Establish broader, stricter water quality standards for nutrients and chemicals.

– Update stormwater standards for urban and agriculture.

– Require agriculture to treat stormwater before it leaves their properties.

– Eliminate the presumption of compliance with water quality standards given to agriculture.