Drones or remotely piloted aircraft systems (RPAS) are emerging as a powerful tool to supplement the conventional monitoring and studies in wildlife biology in terms of individual detection, population surveys, and behavior tracking of wild animals in low-accessible extreme or maritime environments.
Unlike conventional wildlife monitoring, which mainly relies on traditional field surveys, i.e., direct observations by the naked eyes or binoculars, on-site image acquisition at fixed spots, and sampling or capturing under areal constraints, drones successfully use advanced imaging sensors to detect wildlife, such as high-resolution RGB and thermal imaging sensors, with superior detection capabilities. This allows drones to conduct efficient observations and quantitative monitoring of wild animals.
Currently-available drones are small, cost-effective, easily maneuverable, and capable of mounting miniaturized imaging sensors for flexible operations, such as visual interpretation and quantitative analysis of wild animals.
Aerial surveys using manned aircraft require high operating costs, especially for repetitive flights, even when investigating a small area. This method is adequate for medium to large mammals, which are detectable from relatively higher flight heights. Sometimes, publicly available satellite images are also commonly used to monitor land-cover types. But these mid to low-resolution satellite images are not feasible for the direct monitoring of individual animals.
Different types of drones like a quadcopter, hexacopter, and octocopter with higher degrees of freedom are used to allow researchers to study spatial ecology at close range since they can fly to an area that is dangerous for researchers and their manned aircraft to approach, such as narrow fjords and fragmented sea ice, ensuring the safety of researchers from becoming too close to fierce wild animals. Besides, the equipment price of drones is at least ten times cheaper than that of a helicopter.
Individual detection & population survey
One of the most common research objectives of drones in wildlife biology is individual detection and population survey. Traditionally, individual detection is done by human verification by observing if a target species exists in a given area.
Drones make it easy to identify and count birds or mammals in cryptic habitats, based on their homoeothermic body temperatures from the surrounding backgrounds, such as rainforests, even with a partially exposed body through leaves and other obstacles. They can even detect small cryptic nests. Aerial photographs from the drone are very efficient for estimating the population size and examining the density or distribution of endangered species. This can save a lot of time and resources. This method has less variations and more accuracy than a group of human researchers, using direct observation with binoculars.
In addition to identifying and counting wild animals, drones are very efficient in observing the behavior and habits, such as courtship and mating behaviors. Behavioral studies using a drone can leverage video recordings or a series of images to estimate these collective behaviors. In marine animal studies, a drone video survey has added advantages in reducing human-induced disturbance to the animals and reducing the cost of observing, compared to traditional monitoring methods.
One of the significant advantages of deploying a drone is to secure safety. Cautiously operated drones reduce unexpected dangers and damages to human life while exploring an unfamiliar area firsthand. This also produces fruitful results in extreme environments such as the polar regions and deserts or topographically inaccessible zones, such as seaside cliffs that researchers cannot easily approach.
The Arctic and Antarctic regions are notorious in their atmospheric conditions against any monitoring or wildlife research due to cold and windy environments. Therefore, drones are preferred while exploring these inaccessible areas, including oceans with floating ice or narrow fjords, which is risky for piloting manned aircraft due to sudden gusts of wind.
All in all, drones and imaging sensors can contribute to wild animal studies, including identifying individuals from backgrounds, counting detected individuals, and monitoring. The drone is a useful tool for detecting and monitoring wild animals, particularly in extreme environments such as polar regions, by helping researchers find cryptic animals and nests in more secured fieldwork conditions.