Juvenile green turtles on the northern edge of their range: mtDNA evidence of long-distance westward dispersals in the northern Pacific Ocean

A groundbreaking study reveals that juvenile green turtles, found at the northern edge of their range along Japan's Sanriku coast, originate not only from local Japanese rookeries but also from distant Hawaiian and eastern Pacific populations. Using mitochondrial DNA (mtDNA) analysis, researchers identified unique haplotypes in these turtles, suggesting long-distance westward dispersal across the North Equatorial Current. This finding challenges the assumption that northern feeding aggregations are solely sustained by nearby rookeries, with genetic evidence indicating substantial contributions from as far away as Hawaii or the eastern Pacific. The study highlights the complex connectivity of green turtle populations in the Pacific and underscores the need for broader conservation strategies to account for such transoceanic movements.

Nishizawa, H., Narazaki, T., Fukuoka, T., Sato, K., Hamabata, T., Kinoshita, M., & Arai, N. (2014). Juvenile green turtles on the northern edge of their range: mtDNA evidence of long-distance westward dispersals in the northern Pacific Ocean. Endangered Species Research, 24(2), 171–179. https://doi.org/10.3354/esr00592