The 2024 sea turtle nesting season started off with an exciting and rare leatherback nest that produced a total of 40 hatchlings.

Before this year, Sanibel and Captiva had not documented a nest from a leatherback (Dermochelys coriacea) since 2020, which is not surprising since leatherback nests are rare along the Florida Gulf Coast. This nest was the third documented leatherback hatching on the islands since 2009.

Adopt a sea turtle nest to support our work >>

In total across species, there were 843 nests and 16,770 emerged hatchlings this season.

Green Turtles

“Sanibel also saw three green turtle (Chelonia mydas) nests, two of which were confirmed by our night team to be from the same turtle — a newly tagged green nicknamed ‘Guacamole,'” said SCCF Sea Turtle Technician Amanda Manrique. Read more about our nighttime tagging work >>

The season ended with a total of 34 green hatchlings emerging from these nests.

Loggerheads

Loggerheads (Caretta caretta), the most common nesting sea turtles on our beaches, laid 839 nests with 16,722 hatchlings.

“While this number is lower than last year’s record-breaking 1,177 loggerhead nests, it is still in line with counts from previous years,” Manrique said. “Fluctuations in annual nest counts are common, as an individual turtle does not typically nest in consecutive years and may remain in foraging grounds for two to three years after a nesting season before nesting again.”

Lower Hatchlings Counts

The total of 16,770 hatchlings that emerged on this islands this season is lower than the 27,270 hatchlings that emerged in 2023. Lower hatchling counts can be attributed to a number of variables, including extreme heat, excessive moisture, changes in the incubation environment associated with sand placement projects, coyote depredations, and washouts from storms.

Impacts From Storms

This season, two major tropical events impacted Sanibel and Captiva during sea turtle nesting season. Tropical Storm Debby washed out 269 nests when it hit on Aug. 4, a loss of 31% of the total nests laid.

Hurricane Helene arrived on Sept. 26, and seven nests were washed out as a result. Hurricane Milton, while having the greatest impact on our islands themselves, hit on Oct. 9, after the final nest finished incubating, and therefore did not affect this season’s hatch success. 

Learn how tropical storms and hurricanes impact sea turtles >>

Depredation

In recent years, coyote depredation has also greatly impacted nests. Overall, the depredation rate dropped from 2023 but remained above the 10% target.

“This season, nests received one of several treatments in an effort to decrease the depredation rate and evaluate the effectiveness of varying protection strategies,” Manrique said. “Metal cages provided the greatest amount of protection and afforded the lowest depredation rate. However, applying the cages is extremely labor intensive and may not be a sustainable option into the future.”

Ground habanero pepper was as effective as metal screens alone, and both had similar depredation rates as nests with rebar anchoring screens. These results will be used to further assess protection efforts in future seasons.

“While it is unfortunate to have a season with low hatch success, it is important to remember that the factors that impact nesting success vary from season to season,” Manrique said. “The SCCF sea turtle team is committed to continuing research efforts to identify the sources of low hatch success and provide data-driven solutions to resource managers.”

SCCF’s sea turtle program activities are authorized by Florida Fish and Wildlife Conservation Commission Marine Turtle Permits 047 and 170.