Genetic identification of Kemp’s ridley sea turtle from eggshells found at a depredated nest at a novel nesting site.

Abstract

Sea turtles return to the same nesting grounds each year but due to factors such as climate change and anthropogenic development are forced to find novel nesting sites. Identifying sea turtle species using these novel sites is key to conservation. A depredated sea turtle nest was found at a novel nesting site in Alabama in the Summer of 2019. Based on the reproductive biology and natural history of turtle species inhabiting the region, this nest is most likely to have been one of three species known to inhabit the Northern Gulf of Mexico: Loggerhead, Kemp’s ridley, or Green. Predation left limited evidence including relative size of the nest and eggshells devoid of any other tissues that could be used to determine turtle identification. Genomic DNA extraction from eggshells returned low yields due to limited amounts of DNA found within eggshells as well as the storage conditions of samples prior to extraction. Isolation required use of liquid nitrogen and an extended incubation in lysis buffer to maximize yield. DNA was then amplified, and the turtle identified as a Kemp’s ridley sea turtle (Lepidochelys kempii, Garman 1880).