A Remarkable Event on Sanibel Island
On June 28, the Sanibel-Captiva Conservation Foundation’s (SCCF) sea turtle team documented a significant event: the hatching of a rare, endangered leatherback turtle nest on Sanibel’s west end. During the inventory of this nest, SCCF biologists and permitted volunteers recorded 113 eggs, with 40 successfully emerged hatchlings.
Historical Context of Leatherback Nesting
Leatherback nesting on the Gulf coast of Florida is a rare occurrence. The SCCF has only documented such nesting in three previous years: 2009, 2015, and 2020. Generally, leatherback nests account for only a few of the more than 1,000 sea turtle nests laid annually in Florida.
“Most leatherback nesting occurs on the east coast of Florida, primarily in Martin and Palm Beach Counties,” stated Kelly Sloan, Coastal Wildlife Director.
In both 2009 and 2015, only a single nest was documented each year. However, in 2020, six nests were laid across Sanibel and Captiva, with additional nests recorded along the central and southwest coasts.
Notable Moments from 2020
The year 2020 was significant for leatherback nesting on the Gulf coast. The first leatherback was satellite-tagged in collaboration with Florida Leatherbacks Inc., earning the name “Juniper.” By the time of her tagging, three nests were already present on the islands. Post-tagging, it was confirmed that Juniper nested multiple times on Sanibel, Captiva, and Cayo Costa.
Tracking data from Florida Leatherbacks Inc. showed Juniper traveled approximately 2,300 miles along the Gulf coast after her last nest on June 17, 2020, before her tracker ceased sending signals.
Leatherback Hatchings on Captiva and Sanibel
In 2020, Captiva saw its first leatherback nest, with 51 hatchlings successfully emerging from 89 eggs. This was the only successful hatching among the six nests, which collectively contained 504 eggs. No hatchlings emerged from the other five nests.
Compared to other sea turtle species, leatherbacks generally have a lower hatch success rate, a subject of ongoing research across the state.
The 2023 Leatherback Hatching
With an average of 700 loggerhead sea turtles nesting on Sanibel and Captiva from May to October, this year’s leatherback nest marks only the third time that SCCF has documented leatherback hatchlings on these beaches.
In 2009, SCCF recorded the first leatherback nest hatching on Sanibel’s east end, with 90 hatchlings emerging from 106 eggs. The 2015 leatherback nest, located on Sanibel’s west end, did not hatch due to being washed over nine times, resulting in 57 unhatched eggs and six spacer eggs.
Conclusion
The SCCF continues to play a vital role in monitoring and documenting the nesting activities of endangered sea turtles, contributing valuable data to the ongoing efforts to protect these magnificent creatures. The successful hatching of the leatherback nest this year is a testament to the dedication and hard work of the SCCF team and their volunteers.
