Distribution of global sea turtle nesting explained from regional-scale coastal characteristics.

Year: 2024 DOI: https://doi.org/10.1038/s41598-023-50239-5

Extra Information

Christiaanse, J.C., J.A. A. Antolínez, A.P. Luijendijk, P. Athanasiou, C.M. Duarte, and S. Aarninkhof. 2023. Distribution of global sea turtle nesting explained from regional-scale coastal characteristics. Scientific Reports 14, 752, https://doi.org/10.1038/s41598-023-50239-5


Climate change and human activity threaten sea turtle nesting beaches through increased fooding and erosion. Understanding the environmental characteristics that enable nesting can aid to preserve and expand these habitats. While numerous local studies exist, a comprehensive global analysis of environmental infuences on the distribution of sea turtle nesting habitats remains largely unexplored. Here, we relate the distribution of global sea turtle nesting to 22 coastal indicators, spanning hydrodynamic, atmospheric, geophysical, habitat, and human processes. Using state-of-the-art global datasets and a novel 50-km-resolution hexagonal coastline grid (Coastgons), we employ machine learning to identify spatially homogeneous patterns in the indicators and correlate these to the occurrence of nesting grounds. Our fndings suggest sea surface temperature, tidal range, extreme surges, and proximity to coral and seagrass habitats signifcantly infuence global nesting distribution. Low tidal ranges and low extreme surges appear to be particularly favorable for individual species, likely due to reduced nest fooding. Other indicators, previously reported as infuential (e.g., precipitation and wind speed), were not as important in our global-scale analysis. Finally, we identify new, potentially suitable nesting regions for each species. On average, 23% of global coastal regions between −39◦ and 48◦ latitude could be suitable for nesting, while only 7% is currently used by turtles, showing that the realized niche is signifcantly smaller than the fundamental niche, and that there is potential for sea turtles to expand their nesting habitat. Our results help identify suitable nesting conditions, quantify potential hazards to global nesting habitats, and lay a foundation for naturebased solutions to preserve and potentially expand these habitats.