Emerging technologies: Environmental DNA
Photo: Center for Ocean Solutions
Environmental DNA (eDNA) is a new and rapidly improving genetic tool that scientists are using to monitor a wide range of habitats around the world. eDNA is the nuclear or mitochondrial DNA that organisms shed into their environment and can be used to analyze the presence and abundance of populations. Recently, studies have characterized brook trout populations (Baldigo et al. 2016), surveyed marine fishes (Kelly et al. 2014), and discovered novel lineages of deep-sea foraminifera (Pawlowksi et al. 2001) using eDNA techniques. Using eDNA technology allows researchers to employ faster, cheaper genetic methods that allow for increased sampling intensity and spatial ranges of studies.
For example, the Center for Ocean Solutions (COS), a collaboration between Stanford University (Stanford Woods Institute for the Environment and Hopkins Marine Station), the Monterey Bay Aquarium, and the Monterey Bay Aquarium Research Institute is developing a large-scale eDNA project to study populations in the ocean. Using eDNA, COS is working to monitor the abundance of fishes, invertebrates, and marine mammals in locations including the Florida Keys, Monterey Bay, and the Flower Garden Banks National Marine Sanctuariers. The work in this project includes ground-truthing and evaluating the feasibility of these methods, surveying the spatial and temporal variability of marine eDNA, and integrating eDNA into the national marine biodiversity observing network (MBON). Learn more at: http://www.centerforoceansolutions.org/project-environmental-dna.
While there are still many challenges and much to learn about the applications of this new technology, many marine scientists are beginning to use this method to learn more about key populations in our oceans. Check out these scientific studies for examples on the use of eDNA in the marine environment:
Baldigo et al. (2016) Efficacy of Environmental DNA to Detect and Quantify Brook Trout Populations in Headwater Streams of the Adirondack Mountains, New York. Transactions of the American Fisheries Society. 146: 99
Kelly et al. (2014) Using environmental DNA to census marine fishes in a large mesocosm. PLoS One 9:e86175
Pawlowksi et al. (2001) Novel lineages of Southern Ocean deep-sea forminifera reveal by environmental DNA sequencing. Deep-Sea Research Part II 58:1996-2003
Port et al. (2016) Assessing vertebrate biodiversity in a kelp forest ecosystem using environmental DNA. Molecular Ecology. 25:527–541