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Critical Update
Sea Turtles in South Walton are currently stressed by tourist paraphernalia left on the beach overnight that results in failed nesting (false crawls) by nesting females.
We have lost hatchlings because of lighting disorientation. Emerging hatchlings will head for the brightest horizon. On a natural dark beach this is the starlit or moonlit sea horizon. In South Walton, it is increasingly lights from commercial and residential structures lighting the opposite horizon. Hatchlings head inland and die.
Many inquiries have been made about possible effects on the turtles from beach renourishment. The renourishment process, which artificially rebuilds eroded beaches with dredged or trucked-in sand, has been used extensively in other coastal areas, but not in the panhandle, until Bay County's recent project.
Because our beaches are unique and the process has not been studied here, many questions remain. It is known that panhandle beach sand, because of its very small grain size, is much more highly compact than the sand in the rest of the state.
Renourished beaches built elsewhere have compacted into a higher density than the natural beach, which has necessitated periodic tilling to soften the sand enough for the turtle to dig into with her flippers. Prior to the start of the current nesting season, Bay County tilled its new beach.
Last year, during the first nesting season on a renourished panhandle beach, the coordinator of Bay County's turtle program had to relocate most sea turtle nests because the turtles were laying close to the water, near the escarpment that formed after the renourishment.
The other effect noticed in Bay County is reduced incubation time. While hotter temperatures may have contributed to this, the coordinator is confident that the darker sand used for the project has resulted in a hotter beach. Since the sex of the hatchlings is temperature dependent, this may skew the sex ratio of the turtle population. |
