ABSTRACT
Palaparthi, J.; Briggs, T.R., and Hauptman, L., 0000. Variability of beach sediment and sea turtle nesting, hatching, and emergence patterns during the 2019 nesting season northern Palm Beach County, Florida, U.S.A.
Beaches provide essential nesting habitat for threatened and endangered sea turtles. Palm Beach County, Florida is a medium- to high-density nesting location for loggerhead, green, and leatherback sea turtles. However, three quarters of the beaches in Palm Beach County are classified as critically eroding, restored by adding sediment as beach nourishment. Sediment is often used from upland mines, an offshore borrow source, or an adjacent inlet. The textural properties of sediment from these different borrow sources can vary, which may influence substrate temperature and potentially affect the hatching success of incubating sea turtle clutches. To support a healthy ecosystem, it is important to quantify the physical characteristics of placed sediments and evaluate whether there is any influence on successful sea turtle nesting, hatching, or emergence success. This study evaluates spatiotemporal variability of sediment characteristics (i.e. mean grain size, sorting, carbonate content) and the substrate temperature of nourished and non-nourished beaches in northern Palm Beach County, Florida to determine whether there is an influence on sea turtle nesting, hatching, and emergence success. Loggerhead sea turtles (Caretta caretta) were the only species found to have a correlation among nesting, hatching, and sediment characteristics. A hot-spot analysis in GIS identified a preference of leatherbacks (Dermochelys coriacea) to nest on nourished beaches, whereas greens (Chelonia mydas) and loggerheads preferred the non-nourished beaches. Results from this study can aid in understanding best management practices for the future of sandy beaches that provide optimal habitat for sea turtle reproduction efforts.
