eDNA tool a leap in progress detecting endangered frog species in BC

A new genetic tool developed by University of Victoria researchers can detect an endangered species' DNA from water, making environmental impact assessments more effective and reliable.

The eDNA—or environmental DNA—technology detects the presence of a species in a matter of days. Traditionally, it can be weeks in the field for researchers to make direct observations for site assessments undertaken for a variety of reasons such as tracking invasive species or identifying possible constraints for natural resource development.

"Ecological survey methods can be logistically challenging, time-consuming and expensive. With eDNA, a researcher can scoop up water samples and basically do 'CSI for fish and wildlife,'" says Caren Helbing, a UVic professor of biochemistry and microbiology. "The technology allows us to see the unseen. It is a game changer for science as it allows researchers to determine a higher detection success rate in a very short period of time, while cutting costs, time and impact on the environment."

eDNA refers to the genetic material that an organism releases into the environment such as skin cells, feces and mucus. The eDNA technology features the use of an IntegritE-DNA test that can be used by regulators, resource developers and First Nations for enhanced detection reliability, says Helbing. "The ultimate goal is for broader regulatory and public acceptance of eDNA."

Helbing and her coworkers at UVic and Hemmera Envirochem Inc. used the technology, which has a patent pending, to confirm the presence of the coastal tailed frog west of Lillooet, BC. The innovation helped identify the existence of tailed frog DNA at a rate 10 times higher over the course of five days compared to traditional surveying methods conducted previously over a four-year period, according to research recently published in the open-access journal PLOS ONE. This resulted in a tripling of the known range of this species.

From 2000 to 2013, four previous studies examined 292 sites using traditional ecological survey methods in multiple regions west of Lillooet. The occurrence of frogs was low at about 7.9 per cent. Helbing’s research, conducted over five days in 2016, detected tailed frog DNA at a higher rate of 76 per cent.

A big problem in detecting eDNA is making sure that the test is working properly, says Helbing. Thinking that a species is not there when the DNA was actually too degraded or contaminated with impurities could have serious consequences. IntegritE-DNA determines that the DNA quality is good enough for testing to achieve more reliable and less-biased results. The technology can be applied to a broad range of fish and wildlife species.

The work was funded by the Fish and Wildlife Compensation Program and the BC Ministry of Environment and Climate Change Strategy.

A press kit containing a high-resolution photo is available on Dropbox.

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