Cooperative Fish and Wildlife Research Units Program: South Carolina
Education, Research and Technical Assistance for Managing Our Natural Resources


Population distribution of green turtles at Palmyra Atoll, Central Pacific: Insights from mtDNA and dispersal modeling. 2013. Naro-Maciel E, Gaughran SJ, Putman NF, Amato G, Arengo F, Dutton PH, McFadden KW, Vintinner E, Sterling EJ. Journal of the Royal Society Interface

Abstract

Population connectivity and spatial distribution are fundamentally related to ecology, evolution, and behavior. Here we combined powerful genetic analysis with high quality simulations of particle dispersal in an ocean circulation model to investigate the distribution of green turtles foraging at the remote Palmyra Atoll National Wildlife Refuge, Central Pacific. We analyzed mitochondrial sequences from turtles (n = 349) collected there over five years (2008 - 2012). Genetic analysis assigned natal origins almost exclusively (~97%) to the West Central and South Central Pacific combined Regional Management Units. Further, our modeling results indicated that turtles could potentially drift to Palmyra Atoll via surface currents along a near-Equatorial swathe traversing the Pacific. Comparing findings from genetics and modeling highlighted the complex impacts of ocean currents and behavior on natal origins. Although the Palmyra feeding ground was highly differentiated genetically from others in the Indo-Pacific, there was no significant differentiation among years, sexes, or stage-classes at the Refuge. Understanding the population distribution of this foraging population advances knowledge of green turtles and contributes to effective conservation planning for this threatened species.