Like many people my age, the first time I heard of drones was in a military-context. Calculated killers – drones to me were nothing more than murderous machines sent to make people disappear. With the conception of Amazon’s drone delivery service, I was still told to be weary of drones. Popular articles warned of Big Brother and constant surveillance – an omnipresent threat able to see you naked in your home.
It wasn’t until taking geography courses in college – and even up until I researched for this blog post – that I gained a friendlier perspective on drones. Over the past decade, drones have been the forefront of environmental and conservation research, mapping land-use changes and protecting ecosystems. With this change in context and perspective, drones left me with several questions – What are they exactly? How do they work? And, can they help the Earth?
Known as unmanned aerial vehicles (UAV), drones are flying vessels with no on-board pilot. Drone flight paths are either pre-programmed via computer software or determined real-time by a remote control on the ground. Ranging from the size of commercial airplanes to hobby-shop toys, drones are designed differently depending on the load they will carry and the distance they are expected to travel. Two typical designs for UAVs include: fixed wing (which are usually larger – flying for longer distances and carrying more weight) and rotary wing (which are usually smaller but can hover in the air and require less space for lift off and landing)[1]. While militaries use large drones, conservation researchers utilize small, commercially-available drones (either fixed or rotary wing) mounted with a still-frame or video cameras. Once launched, the drones take pictures of the land-below, providing scientists with a highly accurate bird’s-eye perspective of the Earth[2],[3].
Left: A commercial rotary-wing droneSource: irevolutions.org Right: A commercial fixed-wing drone. Source: popularmechanics.com
Before UAVs, conservation workers and scientists often relied on satellite imagery to monitor changes in landscape. However, several challenges arose with this practice. First, the cost of high-resolution satellite imagery is often prohibitive for small agencies and researchers based in developing countries. Some low-resolution imagery is available for free, but lacks the accuracy required for scientific research. Secondly, because satellites are positioned in the exosphere of the Earth’s atmosphere, above clouds, it can difficult to get clear images of tropical and temperate regions where there is always some cloud cover. Thirdly, satellite images take years to update; images readily available now may not show what the ground looks like today. Using commercial drones for research mitigates these problems because they are affordable (approximately $3,000) low-flying, and fast[1],[2].
Though some researchers have used expensive, specialist UAVs – like those used in the movie industry or for law enforcement - a 2012 study pioneered by Dr. Lian Pin Koh of the National University of Singapore brought the idea of using affordable drones for research into the spotlight. Dr. Koh and his colleagues set out to find an affordable way to survey deforestation in Indonesia. Faced with the aforementioned challenges of affordability and rain-forest cloud cover, Koh and his team designed the new Conservation Drone using only publicly-available resources.
Meant to be affordable and easy to use, their prototype was built using a $100 model airplane from Hobby King. Within its fuselage, the team installed an ‘ArduPilot Mega’ (APM), as well as two still-frame cameras (a Canon IXUS 220 HS and a Pentax Optio WG-1 GPS) and a GoPro HD Hero video camera. An APM is an open-source tool containing “a computer processor, GPS, data logger, pressure and temperature sensor, airspeed sensor, gyroscope, and accelerometer.” It allows for a remote-controlled airplane to become an “autonomous drone,” meaning it now flies using preprogrammed flight paths rather than a remote. The team also utilized another online tool, the Canon Hack Development Kit, a customizable script allowing the user to set a time-interval for the camera to take pictures[2].
After sending the Conservation Drone on several missions, Dr. Koh and his team’s found the photos taken were a great improvement to those taken by satellites because the image-quality allowed researchers to identify different types of land-use, as well as see humans and other large mammals clearly. Most importantly, the Conservation Drone is affordable and utilizes open-source software, meaning it can survey forests faster and for a lower cost than humans or satellites, and its software updates are fast, comprehensive, and accessible since they are designed by the general public rather than a small research team[2].
Dr. Koh’s Conservation Drone is great example of affordable and accessible innovation – so much so that it has been used for several other projects. Commercial UAVS inspired by the Conservation Drone have been used to find whales off Japan, count orangutan nests in Indonesia, track elephants in Kenya[1], and measure species richness in China3. The Conservation Drone has found a new application in law enforcement as several government agencies begin using drones for anti-poaching and anti-fishing campaigns. In the Nepal’s national parks, were foot patrol by soldiers is the main method of law enforcement, drones allow for a faster and safer method to watch for tiger poachers[2]. Similarly in South Africa, drones are being used by the Olifants West conservancy to discourage the poaching of rhinos for their horns[4].
Land is not the only place where drones are being used for conservation. As recently as 2016, researchers have begun utilizing commercial UAVs in the mapping of coastal marine environments. In addition to the previously discussed issues of using satellite images, water presents a whole new set of challenges for photo-taking. Two studies, one sponsored by the NASA’s Ames Research Center in California and the other by the University of Bremen in Germany, have attempted the produce 3D models of coastal reefs using drones and SfM (Structure from Motion) modeling programs. In both cases, water transparency, light reflection, and image distortion were critical problems when processing drone-acquired images and calculating accurate models. Scientists found that there is still a lot of work to be done in improving the accuracy of rendered models[3],[4]. However, the images and models attained from drones where more detailed than those based on satellite images, and “consumer-grade drones can be effective [for the] monitoring of coral reefs at [the scales] of SCUBA or snorkeling surveys[6].”
As much as this blog post is intended to highlight the potential of drones in environmental research, it is still important to consider how drones will affect the communities they are used in. As I mentioned in the beginning, the stigma accompanying drones conjures negative feelings for many people. Consent and privacy are big concerns with the growing popularity of drones, especially with law enforcement. This presents a number of legal questions – What is the best way to regulate drones? Can they be used to track specific people? When does their use require a person’s consent or a warrant?
Another side of the problem is psychological well-being – will members of the community populated with drones feel anxious about or suspicious of their purpose – even if the equipment is intended for conservation? Finally, research- especially environmental and geographical research – depends heavily on local knowledge and working with the surrounding community to solve problems. Drones have the potential to create a barrier between locals and researchers if drones are used to enforce laws on locals in conservation areas. Additionally, if drones replace human surveyors and patrols, they may limit the number of employment opportunities available for people in the community[1].
The impact of drones on people and wildlife is by no means clear; however, UAV technology is improving and becoming more accessible every day. Drones have great potential for research and biological conservation, especially for researchers with limited means. These flying-machines are definitely in our future, but it is our job study to monitor how they affect people, as well as see what we can discover.
[1] Sandbrook, Chris. “The Social Implications of Using Drones for Biodiversity Conservation.” Ambio, vol. 44, no. S4, 2015, pp. 636–647. Springer, doi:10.1007/s13280-015-0714-0.
[2] Koh, Lian Pin, and Serge A. Wich. “Dawn of Drone Ecology: Low-Cost Autonomous Aerial Vehicles for Conservation.” Tropical Conservation Science, vol. 5, no. 2, 9 July 2012, pp. 121–132. Mongabay Open Access Journal, doi:10.1177/194008291200500202.
[3] Zhang, Jian, et al. “Seeing the Forest from Drones: Testing the Potential of Lightweight Drones as a Tool for Long-Term Forest Monitoring.” Biological Conservation, vol. 198, 18 Apr. 2016, pp. 60–69. JSTOR, doi:10.1016/j.biocon.2016.03.027.
[4] Shiffman, Richard. “Drones Flying High as New Tool For Field Biologists.” Science, 2 May 2014, science.sciencemag.org/content/344/6183/459.
[5] Deel, Lindsay. “Using Drones for Conservation.” Frontiers in Ecology and the Environment, vol. 12, no. 2, 1 Mar. 2014, pp. 93–93. JSTOR, www.jstor.org/stable/10.2307/43187714?ref=search-gateway:f9413114eab111b09ace25d6c8b274f8.
[6] Chirayath, Ved, and Sylvia A. Earle. “Drones That See through Waves - Preliminary Results from Airborne Fluid Lensing for Centimetre-Scale Aquatic Conservation.” Aquatic Conservation: Marine and Freshwater Ecosystems, vol. 26, 12 Mar. 2016, pp. 237–250. Wiley Online Library, doi:10.1002/aqc.2654.
[7] Casella, Elisa, et al. “Mapping Coral Reefs Using Consumer-Grade Drones and Structure from Motion Photogrammetry Techniques.” Coral Reefs, vol. 36, no. 1, 28 Nov. 2016, pp. 269–275. Springer, doi:10.1007/s00338-016-1522-0.