About eDNA

eDNA (environmental DNA) refers to the genetic material found in an environmental sample (water or sediment). This material may come from microorganisms such as algae and bacteria or fragments of tissue from larger organisms such as feces, gametes, scales, and cellular material. eDNA analysis can identify what species are in a system through the byproducts they leave in their environment, without having to capture and identify living organisms.

The project utilizes two types of eDNA methods. Single species Polymerase Chain Reaction (PCR) (below, left) assays are a rapid, low cost method of identifying a single species in a sample, such as a particular invasive or rare species of interest. Metabarcoding (below, right) identifies multiple species, but is more complex to analyze.

Why eDNA in estuaries?

Estuaries are unique and delicate environments. As a transitional ecosystem, they host not only true estuarine species but also freshwater and marine visitors who may come to the estuary to spawn or feed. Shifting tidal zones, variable salinity, sediment disturbance, and other features of estuary systems mean that they have long required a unique approach compared to freshwater and oceanic systems. eDNA methods are no different – we must develop tools that are appropriate for the environments where they will be applied.

Through genomics we can develop improved methods to track the biodiversity of estuaries and detect the presence of invasive species who may upset the fragile balance of these ecosystems. We aim to provide tools that will aid the researchers and resource managers who study and protect these precious systems.