Environmental Impacts on Loggerhead Sea Turtle Nesting on Edisto Island, South Carolina

• Main Author: Goins, Faythe J.
• Format: Text
• Language: unknown
• Published: DigitalCommons@UMaine 2018
• Subjects: Loggerhead Sea Turtle; Marine Science; South Carolina; Environmental Impacts; Marine Biology; Botany Bay; Edisto; Northwest Atlantic
• Online Access: https://digitalcommons.library.umaine.edu/honors/331; https://digitalcommons.library.umaine.edu/context/honors/article/1332/viewcontent/Goins__Faythe_Thesis_2018.pdf

The Northwest Atlantic population of loggerhead sea turtles (Caretta caretta), listed as threatened on the US Endangered Species List, may be susceptible to climatic changes and monthly variation due to their slow generation time, temperature dependent sex determination, natal homing, and anthropogenic impacts. In order to investigate how environmental conditions impact loggerhead sea turtles, we compared sea turtle nesting data collected on three distinct and unique beaches on Edisto Island, South Carolina (Edisto Beach State Park, Edisto Town Beach, Botany Bay Plantation) between 2009 and 2016 to environmental data downloaded from NASA Giovanni and NOAA. We found that incubation period was negatively correlated with average air temperature across the time of incubation (p<0.0001). Incubation period was positively related to cumulative precipitation (p<0.0001) and percent cloud cover (p<0.001) on all three beaches; however, these factors account for only a small proportion of the variation in incubation period. Our results also indicated that over the course of the nesting season incubation period followed a quadratic pattern (p<0.0001) and average clutch size decreased linearly (p<0.0001). Although percent mortality did not show a strong relationship with air temperature, personal observation and previous studies suggest that loggerheads with shorter incubation periods are weaker and slower than those with longer incubation periods. It is important to further investigate the environmental impacts on loggerhead sea turtles, in order to evaluate and potentially mitigate the effects of climate change on this ecologically important resource.