A recent study published by University of Guelph biologist Mehrdad Hajibabaei and his team searched for environmental DNA (eDNA) in water from 18 Ontario rivers.

Organisms shed DNA through skin, scales and feces. Using those traces, researchers identified hundreds of aquatic invertebrates that had not been found through traditional methods.

Only 22 species identified through traditional methods were not detected by the DNA survey. Many species were found at just one site, showing how much river life can be missed.

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People who work, play or live beside the water may know little about its inhabitants. That can put species at risk, Ricciardi suggested.

“How would people who don’t know what’s living underwater feel any empathy or any sense of loss?”

link to open access paper https://onlinelibrary.wiley.com/doi/10.1111/mec.70377