According to scientists from Lund University in Sweden, insect DNA was collected from the air and used for the first time to detect 85 species of insects.
Bees, moths, flies, beetles, wasps and ants have all been identified in a study that has raised hopes that airborne environmental DNA (eDNA) could become a useful tool for monitoring insect abundance and biodiversity decline.
The study, which took air samples from three locations in Sweden, also found evidence of plants, algae, fungi and vertebrates, including a wood pigeon, fieldfare, hedgehog, squirrel and short-tailed vole, as well as domesticated animals – chickens, cows and dogs.
The results, which have yet to be peer-reviewed, will be presented this week at the British Ecological Society’s Ecology Across Borders conference by lead author Fabian Roger.
“Given the biodiversity crisis, we urgently need better information on the status and distribution of species,” said Roger. âOur study is a proof of concept showing that we can detect DNA from insects and vertebrates from the air that was collected under natural conditions. This opens up many exciting possibilities for species monitoring and identification, which could enable us to comprehensively monitor biodiversity on large spatial and temporal scales. “
EDNA sampling has so far focused on aquatic ecosystems and is carried out by ecological consultants looking for crested newts.
In this study, researchers compared airborne eDNA sampling to traditional insect surveys, including moth light traps and transect migrations, which typically only capture larger insect species.
While traditional light traps detected 48 species of moth, only nine species of moth were detected with eDNA, although five of them were overlooked by traditional traps. Of the 36 butterfly and bee species identified through a transect walk, five species were detected by eDNA samples.
EDNA sampling was more successful in detecting a wider range of arthropod species, with a total of 67 species found at the light trap and 20 at the transect site.
According to Roger, the development of airborne eDNA sampling to complement traditional methods requires increasing the sensitivity of the sampling to achieve more reliable detection and a better understanding of how airborne eDNA is created, transported and degraded.
“We are at the very beginning of research into airborne environmental DNA for anything other than bacteria, pollen or spores – and even there we only scratched the surface,” he said. “Just because it doesn’t work perfectly right away doesn’t mean it never works and the potential is huge.”