e-DNA maps out critical habitat use of species at risk

May 17, 2021

Increasingly, the world is seeing a decline in biodiversity. Monitoring and managing this decline is no small matter, by their nature as species decline and reach tiny numbers they are very tricky to empirically monitor. The Blandings turtle is one example, a yellow-chinned turtle of wetlands that is now threatened, and like all other declining species we simply do not know enough about where it resides to create good policy to save it.

 Blandings Turtle


Enter the emerging biotechnology of e-DNA. A fascinating technique that can identify the DNA of species from a sampled water vial. Organisms like the Blanding’s Turtle shed DNA into the environment and this biological remnant allows us to trace the presence of the turtle thanks to DNA barcoding.  Think how easy that is, a management agency simply goes to wetlands and gathers water samples and takes them to the lab – a far cry from finding them in the field where turtles can be extremely elusive, buried in mud or moving slowing unseen in the dark waters. This information, where they are, allows us to clearly identify geographical zones that can then be used for implementing effective policy. Without it, the growing human footprint is likely to recklessly decimate some of their only remaining hotspots.

In a new article, Tarof. et al use e-DNA to investigate wetlands inhabited by the Blanding’s turtle in Ontario, Canada. In their experiments, the researchers gather water from different areas of a given wetland, and trace e-DNA for each sample. They employed positive and negative controls (i.e., knowing where the turtles were and were not) and used their e-DNA techniques to see if they could locate the low- density animals. The technique worked surprisingly well, finding 50% matches that appeared to correlate to the known local densities of the turtle. Their findings aid a critical empirical results to a growing literature that is beginning to strongly suggest that e-DNA is a powerful tool for species at risk (link). 

To read the article summarizing this new research on the Blanding’s turtle using e-DNA biotechnology, please see the link below:

Environmental DNA bioassays corroborate field data for detection of overwintering species at risk Blanding’s turtles (Emydoidea blandingii) (cdnsciencepub.com)