Exploration of eDNA Analysis to Assess Endangered Sea Turtles

There is a need to innovate the approach to monitoring endangered sea turtle populations, as traditional approaches are limited in their ability to characterise all life stages of these elusive animals. Analysis of environmental DNA (eDNA) is a powerful tool for detecting endangered or rare species because it provides a rapid, non-invasive means of species detection. However, there were no published studies investigating the use of eDNA analysis to detect sea turtles in natural conditions. We tested two primer sets designed to amplify DNA extracted from tissue samples used in population assessments of the green sea turtle, Chelonia mydas. Both primer sets successfully amplified DNA fragments of differing lengths (488 bp and 253 bp) from seawater samples collected from SeaWorld aquaria and San Diego Bay, California, USA. Field results and laboratory specificity testing indicated that the primer set which amplified the shorter DNA fragment was a better candidate for eDNA analysis. Our results suggest that with further refinement, eDNA represents a promising tool to detect and monitor C. mydas.