Abstract

To monitor the impact of climate change on sea turtle nesting beaches, we measured the sand temperature at 3 specific nesting locations for loggerhead turtles (Caretta caretta), green turtles (Chelonia mydas), and hawksbill turtles (Eretmochelys imbricata) at Nishinohama Beach on Kuroshima Island, Ryukyu Archipelago, Japan. During the major incubation periods (peak of nesting season) from 2009 to 2023, sand temperature surrounding nests ranged from 28.72°C to 30.45°C for loggerheads, 28.46°C to 30.04°C for green turtles, and 28.60°C to 29.36°C for hawksbills. Estimated historical (since 1897) sand temperatures based on recorded climatology data indicate that sand temperatures at nesting microsite locations increased by 1.29°C, 1.12°C, and 1.18°C per 100 yrs for loggerheads, green turtles, and hawksbills, respectively.