Investigating the effects of nest shading on the green turtle ( Chelonia mydas ) hatchling phenotype in the Ogasawara islands using a field‐based split clutch experiment

Conservation practices such as nest shading can significantly alter the phenotype of green turtle (Chelonia mydas) hatchlings, potentially influencing their fitness. A study conducted on the Ogasawara Islands, an important rookery in the North Pacific, used a field-based split clutch experiment to investigate these effects. Researchers equally divided clutches and placed half under shaded conditions while the other half remained unshaded. Findings revealed that shading produced hatchlings with improved self-righting responses, larger carapace sizes, fewer nonmodal scute patterns, and smaller unabsorbed yolk sacs—indicating potential benefits to their survival. These results suggest that while shading may help mitigate the effects of global warming on sex ratios, its broader implications for hatchling fitness must be carefully considered.

Kobayashi, S., Endo, D., Kondo, S., Kitayama, C., Ogawa, R., Arai, K., Watanabe, G., & Kawaguchi, M. (2020). Investigating the effects of nest shading on the green turtle ( Chelonia mydas ) hatchling phenotype in the Ogasawara islands using a field‐based split clutch experiment. Journal of Experimental Zoology Part A: Ecological and Integrative Physiology, 333(9), 629–636. Portico. https://doi.org/10.1002/jez.2411