Our first project was to find a cheaper way to monitor orangutan populations in Sumatra. Traditionally people have to walk the forest on foot and count the nests in the forest canopy, and from those counts they estimate the population of orangutans. There have been efforts to fly small manned aircraft and count the nests from above, but it’s very expensive to hire an aircraft. Many times pilots wouldn’t even want to fly because it’s quite risky — there’s no way to land the aircraft in case of any emergencies. So we have been flying our UAVs over the rainforest in Sumatra and have managed to get very high-resolution images of these nests. The resolutions can be as high as 1 to 2 centimeters per pixel, which allows us to not just count the nests, but also see what kinds of twigs they are using to build the nest, what kind of leaves, possibly even estimate how long the nests have been left in the tree – all sorts of information biologists had never had before.

Read more of this interview with Lian Pin Koh on Yale’s Environment 360