Small Unmanned Aircraft Systems (sUAS) are evolving at an increasingly rapid rate and are used in conservation for increasingly diverse uses. sUAS are comprised of the minimum of a pilot/ground-based operator, communication system, and an Unmanned Aerial Vehicle (UAV, commonly referred to as a drone).
sUAS are used at The Nature Conservancy (TNC) field offices across the nation to monitor flora and fauna, wildfires and controlled burns, and search for invasive species populations.
The TNC Maui forest program is incorporating sUAS to maintain ungulate-free preserves through more efficient monitoring and hunting assistance. We use a high quality Forward-looking InfraRed (FLIR) camera mounted on a UAV, specifically, a DJI Matrice 210 UAV with a Zenmuse XT2 30Hz (640 x 512) 13mm (45 x 37) camera.
The transition from using our previous UAV (Phantom 4) to the new Matrice set-up in February 2019 was quick and intuitive for our FAA certified pilot, Caleb Wittenmyer. 12.85 hours of piloting yielded very encouraging results that revealed higher quality imaging, longer battery life, the ability to spot ungulates and guide hunters directly to them while maintaining precise location of all hunters, as well as the ability to push animals in lower canopies.
With two pilots, optimal control of imagery, drone location and orientation, and safety and utility can be easily achieved. One pilots the UAV while the other controls the cameras, allowing positions to be relayed to deployed hunters on the ground.
Below, an image of the UAV controller displaying thermal imagery in the main frame, natural color imagery in the lower right corner, and position in the lower left corner.
Above, dual imagery cameras simultaneously capture infrared image with animal blazingly clear (white hot) in the left image, while the same animal is virtually undetectable in the true color imagery to the right. Vegetation is 5-10 ft. tall Kiawe, and UAV is about 20 meters above canopy.
Below, UAV is closer to its higher limit, about 110 meters above ground level. Hunter (near top of frames) and animals (lower in frames) appear in thermal imagery (dark black indicating heat) in the left picture as the darker spots. In contrast, in the true color imagery on the right, only the hunter's blaze orange is barely visible, and the animals are not detectable.
sUAS can be operated at night, or as defined by the FAA, the period 30 minutes after sunset to 30 minutes prior to sunrise with the appropriate waiver. Other things that should be considered when flying at night are canopy height and other obstacles that cannot be seen.
Without the assistance and guidance from UAS operator, the hunter would not have initially spotted the deer through the head-high brush. However, the sUAS operator was able to guide the hunter directly toward animals and the openings in the canopy, leading to a clear, successful shot by the hunter.
sUAS may be ideal for monitoring populations and finding the last few deer in a
small enclosed unit, but may not be the answer to cull large herds, especially in open systems and in dense canopy.
It can also be difficult to direct hunter through thick brush that operator cannot see. Good communications and directional awareness is vital.
Geo-tagged screen display allows for precise geo-referencing and on-the-ground tracking/locating of target and UAV.