As biodiversity diminishes around the world, scientists and conservationists are spending more money to document and understand the changes that are taking place. Conservation ecologist Lian Pin Koh argues that drone technology can be used as a much cheaper way to survey landscapes and document ecological change.
Biodiversity continues to decline around the world, particularly in the tropics, where the majority of global biodiversity is found. Unfortunately, wildlife poaching is also most rampant in these areas, and poses a serious threat to endangered species such as rhinoceros, tigers, and elephants. A change in conservation technology is required to combat these threats.
Conservationists attempting to monitor land-use changes and wildlife trends face serious challenges. For one thing, the satellite-based remote sensing that conservations currently rely on for mapping and monitoring land-use changes is typically too expensive for researchers in developing countries. Furthermore, much of the humid tropics is often obscured from remote sensing satellites due to a persistent cloud cover, so cloud-free satellite images for a specific time period and location are often not readily available.
Conserva- tionists attempting to monitor land-use changes and wildlife trends face serious challen- ges.
Currently, the assessment and monitoring of wildlife is largely achieved through ground surveys, which are often time-consuming, expensive, and logistically challenging in remote areas. As a result, surveys are not conducted at the frequency required to monitor population trends, especially in difficult and inaccessible terrains.
To address these challenges, we have been developing inexpensive, autonomous unmanned aircraft systems (UAS) for surveying and mapping forests, biodiversity, and the threats that they face. These “Conservation Drones” can be equipped with cameras to record high-quality videos and photographs from the air. We have mainly been using consumer-grade compact cameras with built-in Global Positioning Systems (GPS) to geotag our aerial photographs. We also use high-definition action cameras to capture video footage of the landscape, which is useful for detecting poachers and forest fires.
The core component of a Conservation Drone is an autopilot system (ArduPilot Mega, or APM). We convert off-the-shelf model airplanes into UAS by equipping them with the APM system, and use inexpensive airframes to keep costs down. Using an open-source mission planning software, we program the flight path of each mission by clicking on waypoints in Google’s satellite map interface. The drones can be programmed to take off and land autonomously, and to circle over any waypoint for a specified duration or number of turns. Users can also program other flight parameters such as ground speed and the altitude of each waypoint.
Since we began in January 2012, we have carried out more than 200 Conservation Drone flights in Switzerland, the Netherlands, Indonesia, Malaysia, Nepal, Congo, Gabon, Madagascar, the United States, Greenland, and elsewhere. These flights have provided us with a huge number of photographs and videos, which we use to map land use, survey biodiversity, and monitor illegal activities.
From the high-resolution photo- graphs, resear- chers are able to obtain detailed informa- tion about land use, agricul- ture, and settle- ments in the landscape.
From the high-resolution photographs, researchers are able to obtain detailed information about land use, agriculture, and settlements in the landscape. The images can also be used to create three-dimensional models of the forest for extracting useful information such as tree height and tree density.
We have also been able to detect wildlife species and their habitats, including orangutans and their nests, elephants, rhinos, forest buffaloes, and even turtle nests. We are collaborating with colleagues from the computer science discipline to automate the detection and counting of objects captured by Conservation Drones.
Since 2012, organizations like WWF Nepal have been experimenting with the use of UAS for combatting illegal activities like logging and poaching. Geotagged drone images of recently logged areas could help authorities track down those responsible for illegal logging and provide evidence for their conviction. Conservation Drones equipped with high-definition video cameras could also facilitate the detection of smoke from poachers’ campfires many miles away, and a live video feed would allow rangers to patrol the forest remotely, and react immediately when needed.
Conservation Drones is a constant work in progress. We are working with colleagues to equip our drones with a scanning radio receiver that might be used to triangulate the location of animals in the forest that have been tagged with a radio collar. We are also working with WWF Nepal and India to equip drones with thermal imaging cameras, which could detect heat-emitting objects from the ground, helping rangers locate wildlife and poachers at night. We believe that in five to six years, Conservation Drones will be an indispensable part of a field biologist’s toolkit.
Photo credit: Anupam Nath/Associated Press