Environmental DNA Shed by Living Creatures Can Help Us Identify and Save Endangered Species

Separate team of researchers have discovered a unique way of detecting traces of living animals in the air that could help track and save populations of vulnerable, endangered species.

Two new studies of the independent teams published in the journal Current Biology found that environmental DNA (eDNA) shed by living creatures can be captured using "vacuum devices" and filter airborne samples in places where animals had lived.

According to evolutionary genomics researcher Kristine Bohmann from the University of Copenhagen in Denmark, their results were astonishing. "In just 40 samples, we detected 49 species spanning mammal, bird, amphibian, reptile, and fish," Bohmann said.

Both independent research groups, one based in Denmark, and the other based in the United Kingdom, at Queen Mary University of London, and Canada, set out an airborne eDNA test detecting terrestrial animal species collected from two European zoos, Hamerton Zoo Park, UK, and Copenhagen Zoo, Denmark.

DNA from the air

To their surprise, the eDNA detected from the samples also collected genetic traces of meat fed to some of the zoo animals, such as chicken and beef.

Collecting DNA from air is something researchers was far from sure, apart from traditional ways of sampling from water and soil.

"We did not think that vacuuming animal DNA from air would work," Bohmann says. "This was high risk, high reward science with the potential to push the boundaries of vertebrate biomonitoring. Clearly the sky is not the limit."

By coincidence, another team of scientists independently studied the same thing at about the same time in the UK, led by molecular ecologist Elizabeth Clare from Queen Mary University of London. Although each team used different methods in capturing airborne eDNA, both showed success in detecting the presence of numerous animal species within and beyond the confines of the two zoos.

Major implications to global terrestrial biomonitoring

The co-discovery of both teams was "welcomed with serendipity" as one research validates the other. In the subsequent sequencing, the team were able to identify DNA from 25 different species, including several surprising findings.

"We were even able to collect eDNA from animals that were hundreds of meters away from where we were testing without a significant drop in the concentration, and even from outside sealed buildings," says Clare, who is now affiliated with York University in Canada. "The animals were inside, but their DNA was escaping."

Both researches that had been completed separately even before realizing their similarity supports the idea that conservationists and others in the research community can utilize these techniques to "remotely monitor animal populations in the wild - especially endangered species that can often be difficult to find and track using traditional means of observation, let alone comprehensively over time."

"The crisis of declining biodiversity exceeds our current ability to monitor changes in ecosystems," Clare's team writes in their paper.

"f airborne eDNA sampling can be successfully developed, it will have major implications for global terrestrial biomonitoring."

Researchers admit the need for more work to realize full potential of eDNA capturing technique. Nonetheless, the co-discovery encouraged development despite the challenges.