Airborne DNA used to detect insect species, breakthrough for environmentalists

This story was originally published by The Guardian and is reproduced here as part of the Climate Office collaboration.

Insect DNA was collected from the air and used for the first time to detect 85 species of insects, according to scientists at Lund University in Sweden.

Bees, moths, flies, beetles, wasps and ants have been identified in study that gives hope that airborne environmental DNA (eDNA) could become a useful tool for monitoring insect abundance and decline of biodiversity.

The study, which sampled the air from three sites in Sweden, also detected evidence of plants, algae, fungi and vertebrates, including wood pigeon, field bird, hedgehog, red squirrel. and a short-tailed meadow vole, as well as the presence of domestic animals – chickens, cows and dogs.

The results, which have yet to be peer reviewed, were presented last month at the British Ecological Society’s Ecology Across Borders conference, by lead author Fabian Roger.

“In the face of the biodiversity crisis, we desperately need better information on the status and distribution of species,” Roger said. “Our study is a proof of concept that shows that we can detect insect and vertebrate DNA from air collected under natural conditions. This opens up many interesting possibilities for the monitoring and detection of species, which could allow us to comprehensively monitor biodiversity at large spatial and temporal scales. “

The eDNA sampling has so far focused on aquatic ecosystems and is carried out by ecology consultants looking for crested newts.

In this study, researchers compared airborne eDNA sampling with traditional insect surveys, including light moth traps and transects, which typically only capture larger insect species.

While traditional light traps detected 48 species of moths, only nine species of moths were detected with eDNA, although five of them were missed by traditional traps. Of the 36 butterfly and bee species identified by a walk transect, eDNA sampling detected five species.

EDNA sampling was more successful in collecting a wider range of arthropod species, finding a total of 67 species at the light trap and 20 at the transect site.

According to Roger, the development of airborne eDNA sampling to complement traditional methods will require increasing the sensitivity of the sampling to achieve more reliable detection and a better understanding of how airborne eDNA is generated, transported and how it degrades. .

“We are at the very beginning of the exploration of airborne environmental DNA for anything other than bacteria, pollen or spores – and even then we have only scratched the surface,” he said. declared. “Just because it doesn’t work perfectly out of the box doesn’t mean it’s never going to work, and the potential is huge. “