Abstract
The Mediterranean green turtle regional management unit is one of the 17 management units of green turtles considered a global conservation priority. However, previous studies using different genetic markers revealed very little diversity and differentiation across populations due to the overdominance of one haplotype (CM-A13) in the Mediterranean. We, therefore, used a more informative marker, mitochondrial short tandem repeats (mtSTRs), in 431 samples collected along the eastern Mediterranean coasts of Turkey and Northern Cyprus. In addition, we added the mtSTR haplotypes of previous studies and reached a total of 980 samples covering 12 nesting beaches (almost 100% of the populations in the region). We identified 42 haplotypes, 4 of which were recorded for the first time in the region. The species has a genetic diversity in the region higher than previously thought, ranging from 0.54 (Sugözü, Turkey) to 0.934 (Israel) and with the most common haplotypes being 6-8-8–4 (26.5%), 6-8-5-4 (17.3%), and 6-8-6-4 (14.9%). The analysis of a more extensive data set of mtSTRs supported recognizing at least three management units in the Mediterranean. Furthermore, we used the new data to assess the origin of the turtles foraging in Israel. We determined that Samandağ (Turkey) was the population of origin of most of the individuals. Overall, we show that mtSTRs highly improve the resolution to detect population structuring and source for this species and region.
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The authors would like to thank anonymous reviewers and the editor for their constructive comments which improved the manuscript.
Funding
This study is financially supported by The Scientific and Technological Research Council of Turkey (TUBITAK) with project code 117Z996. Carlos Carreras is supported by the Spanish Government projects’ CTM2017‐88080 (MCIN/AEI/10.13039/501100011033 and by ERDF “A way of making Europe” of the European Union), the project PID2020-118550RB (MCIN/AEI/10.13039/501100011033) and is a member of the research group SGR2017-1120 (Catalan Government).
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SK: formal analysis, investigation, data curation, methodology, and writing original draft. OT: conceptualization, methodology, validation, resources, writing original draft, writing—review editing, visualization, supervision, project administration, and funding acquisition. CC: formal analysis, writing original draft, writing—review editing. CY: investigation, resources, writing original draft. BS: investigation, resources, and writing original draft. OC: investigation, resources, and writing original draft. SE: investigation and resources, ME: investigation and resources. AHU: investigation and resources, CU: conceptualization, methodology, validation, resources, data curation, writing original draft, supervision, project administration, funding acquisition, and writing—review editing.
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Karaman, S., Turkozan, O., Carreras, C. et al. Population genetic diversity of green turtles, Chelonia mydas, in the Mediterranean revisited. Mar Biol 169, 77 (2022). https://doi.org/10.1007/s00227-022-04068-1
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DOI: https://doi.org/10.1007/s00227-022-04068-1