Peruvian Amazon – Scientists recently deployed drones equipped with specialized probes to collect environmental DNA from rainforest canopies, exposing a wealth of vertebrate life previously difficult to detect.
One Probe Captures DNA from 50 Species
One Probe Captures DNA from 50 Species (Image Credits: Imgs.mongabay.com)
A single canopy sample yielded genetic traces from as many as 50 different vertebrate species, underscoring the untapped biodiversity in rainforest heights. Researchers from the Environmental Robotics Lab at ETH Zürich partnered with Wilderness International for this pilot project in two protected areas north and south of Peru’s Tambopata River. They flew drones along predefined paths and lowered probes fitted with moist cloth pads into the dense foliage.
The pads rubbed against branches and leaves, capturing eDNA shed by animals through hair, fur, saliva, or other traces. This approach maximized contact to overcome the patchy distribution of genetic material. Automation allowed repeated sampling without constant manual intervention, proving efficient even in challenging terrain.
Traditional Methods Fall Short in the Canopy
Camera traps and acoustic monitors have long dominated biodiversity surveys, yet they frequently overlooked arboreal species in tall, impenetrable forests. Ground-based efforts captured activity at lower levels but missed the treetops, where much of the Amazon’s life thrives amid threats like deforestation for agriculture and mining. Water sampling detected numerous species but ignored those dwelling exclusively in the canopy.
“We have researchers who cover the ground level when it comes to traditional biodiversity research,” Marie Schreiber, head of science communication at Wilderness International, explained. “But what is going on in the treetops is very difficult to understand and assess.”
Key Advantages of Drone eDNA Sampling
The technology offered several breakthroughs over conventional techniques:
- Safe access to remote, elevated habitats without climbing or clearing vegetation.
- Non-invasive collection that preserved ecosystems while gathering comprehensive data.
- Rapid deployment, with flights enabling multiple samples in protected zones facing development pressures.
- Validation against ground surveys, confirming the presence of expected species.
Steffen Kirchgeorg, a postdoctoral robotics researcher at ETH Zürich who developed the system, emphasized efficiency: “We want to maximize the amount that we collect within a given flight.”
Canopy vs. Water: Distinct Biodiversity Signals
Analysis of canopy samples identified 257 vertebrate species overall, far exceeding expectations for such heights. Water samples from the same sites revealed more species in total but showed minimal overlap with treetop detections. Canopy eDNA highlighted unique taxonomic groups absent from aquatic traces, proving the value of multi-method approaches.
This complementarity strengthened conservation arguments in understudied regions with high species diversity but low population densities per species. Schreiber noted the broader impact: “This is data with a lot of impact because it helps in justifying the establishing of new conservation areas and getting funding for them.”
Key Takeaways
- Drone probes detected 257 vertebrate species, including 50 in one sample alone.
- Canopy sampling uncovers groups missed by water-based eDNA, urging combined strategies.
- Technology aids protection amid deforestation threats in Peru’s Tambopata region.
Though costs and logistics pose hurdles to widespread adoption, falling eDNA analysis prices promise broader use. Kirchgeorg anticipates growth: “As eDNA analysis becomes more readily available and cheaper, this will actually really become more feasible.” This innovation not only maps hidden life but bolsters efforts to safeguard it. What strategies do you see advancing rainforest conservation? Tell us in the comments.
