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Researching the Life Stages & Strandings of Sea Turtles

January 22, 2021
The SCCF sea turtle program is focused on ensuring the survival of sea turtles through nest monitoring, research, education, training, advocacy, and habitat protection. Achieving these goals is becoming increasingly complex in the face of coastal development, climate change, ocean plastics, habitat loss, and a wide variety of emerging and worsening threats.
In addition to the identifiable threats, there are also some profound mysteries that sometimes stymie sea turtle conservation efforts.
“Our brief experience with them on the beach provides an important glimpse into their lives, but relatively little is known about sea turtles from the time the tiny hatchlings enter the open ocean until they return 25 to 30 years later to nest as adults,” said SCCF Coastal Wildlife Director Kelly Sloan. “Where do they go when they leave? What route do they take to get there? Where and when are human activities more likely to affect their survival and their health?”
Understanding sea turtle behavior at each of their life stages is critical for ensuring their survival. Satellite telemetry has been used widely to explore these mysteries by tracking their movements at sea and has had profound impacts on in-water conservation efforts, connecting life history, ecology, and hazardous intersections for turtles. SCCF staff members have successfully deployed 17 satellite tags on loggerhead and green sea turtles to help make these connections for the turtles nesting in Southwest Florida.
An unfortunate but important way to learn more about the in-water threats they face is by documenting the sources of morbidity and mortality in strandings (sea turtles that are found dead, sick, or injured). The Sea Turtle Stranding and Salvage Network (STSSN) is a cooperative effort comprised of federal, state, and permitted private partners along the entire coast from Maine to Texas. STSSN participants report sea turtle strandings to a centralized database so that trends and emerging issues can be identified and addressed.
In the decade preceding the 2018 red tide—from 2007 to 2017—an average of 31 strandings were reported annually by SCCF on Sanibel and Captiva. During the catastrophic red tide event, that number skyrocketed to 205 (with an additional 51 reported by CROW). In 2019 and 2020, our stranding totals were 55 and 41, respectively.
The species composition in 2020 was 23 loggerheads (Caretta caretta), comprising 56 percent; 15 green turtles (Chelonia mydas), making up 36 percent, two Kemp’s ridleys (Lepidochelys kempii), and one unidentifiable species due to its state of decomposition. Boat strikes (13) and predation (15) represented the most significant source of mortality last year. It is unknown if these injuries occurred pre- or post-mortem. In six strandings, there were no obvious injuries, and the cause of death could not be determined using external evaluation alone.
Each of these life-cycle puzzle pieces has guided strategic sea turtle conservation for decades. We remain committed to collecting the data that build these national databases to give turtles a brighter future.


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