A proof-of-concept technique has been created by Swiss researchers to gather environmental DNA (eDNA) from high-arching forest canopies, an understudied area. Rather than risking their lives by employing professional climbers to gather a little insect and bird DNA, the team sent a collecting drone into the trees to collect genetic material, providing a fuller picture of the area’s biological breakdown.
The scientists employed a quadcopter outfitted with a sticky collecting cage. However, since tree branches may bend with the smallest touch — and the drone has to contact the branches to gather DNA — it features a haptic-based control method that measures the pressure between the drone and the branch. Then it adjusts its landing, resting softly against the limb to prevent tossing important material to the ground.
The cage of the drone then collects samples using a sticky surface comprised of “adhesive tape and a cotton gauze humidified with a solution of water and DNA-free sugar.” The cage spends about 10 seconds leaning on each branch, collecting eDNA, before zooming back to the base, where the samples are collected and sent to a lab. The drone used in the experiment successfully gathered enough genetic material to identify 21 different animal types, ranging from insects and mammals to birds and amphibians.
The scientists, however, emphasise that this is a work in progress. For example, on the last study day, the researchers noted a decline in eDNA detection due to the previous night’s rainfall, indicating that the technology only informs them which critters visited since the last deluge. Furthermore, they observed inexplicable variances in the performance of their two collectors, emphasising the necessity for further investigation of equipment variables.
Environmental biologists will be able to identify which animals reside in some of the most difficult-to-reach locations, the researchers hope, thanks to their study. The technique might someday help scientists understand how environmental changes influence biodiversity, perhaps assisting in the identification of endangered or fragile species before it’s too late.