Grant: 19-021R
Project Title: Green sea turtle population genetic structure using next-generation sequencing
Project Manager: Eric Hoffman
Organization: University of Central Florida (Research and Educational Institute)
Grant Amount: $16,627.00
Completion Date: 2021-01-15

Summary: Monitoring and understanding the genetic diversity of threatened species is a fundamental requirement for conservation planning. Recent advances in molecular techniques allow researchers to drastically increase the resolution of genetic analyses at a considerably lower cost per sample. Despite its potential importance for understanding conservation biology, sea turtles are under-studied at a population genomics scale, leaving a knowledge gap in determining the best conservation practices for their long-term survival. Although genetic structure of most populations of the green sea turtle (Chelonia mydas) has been previously assessed, there is a growing concern among researchers that population genetic structure should be re-evaluated using more in-depth molecular techniques. Our goals in this project are to reassess genetic diversity and genetic structure of green turtle populations contributing to two juvenile foraging sites in the east coast of central Florida. Specifically, we will use genomic techniques (e.g., ddRADSeq) to assess the number of genetic clusters (i.e., populations) in the Indian River Lagoon (IRL) and at the Trident Submarine Basin (both long-term in-water study sites), and calculate the genetic differentiation among, and genetic diversity within these populations. In addition, given the recent increase in the number of green turtles nesting in Florida, we will use the same molecular techniques to determine if the proportion of juveniles in these sites that belong to the ACNWR population has changed over time. A recent study in the Pacific Ocean used similar molecular techniques and identified genetic differences between nesting populations that were not previously detected using other techniques. Our study will be the first one using this type of methodology for Florida and the North Atlantic green turtle groups, and will serve as a baseline for future fine-scale population genetic reassessments.

Results: Laboratory analyses: We successfully completed all laboratory work proposed for this grant. We have extracted the DNA, prepared libraries for next generation sequencing, sequenced all 300 samples, and received all the sequencing data for processing and analysis. Data processing: Data generated by this grant is still being analyzed for publication, but our preliminary analyses indicate that the protocol we used was able to generate high-quality data necessary for the proposed project.