Drones, also known as unmanned aerial vehicles (UAVs), are lightweight aircraft that are operated from the ground via remote control software. They can carry imaging, data collection and other equipment useful for conservation research and practices. Currently, satellites, manned aircraft and balloons provide aerial data and images, but UAVs offer significant advantages over those other aerial platforms, especially at landscape or hectare scales.
UAVs fly “low and slow” (Anderson, 2013) and are relatively low-cost. So they can fill a spatial and temporal gap between high-altitude aerial observations and hands-on field data collection, and can also overcome the cost-prohibitive factor for both of those alternatives. UAVs can collect data (imaging and non-imaging) more frequently and over a wider range than field researchers. They can cover difficult or sensitive terrain that might be inaccessible otherwise, and can collect data and images at a finer resolution than possible with higher-altitude aerial platforms. If well-operated, they are retrievable and reusable. UAVs allow large amounts of data to be collected with minimal impact and funds. They also offer a unique opportunity for citizen science because government regulations for recreational drone operators are less onerous than for commercial or NGO operators (Vlasits, 2017).
Those government regulations are one of the limitations of this technology. Federal aviation rules for recreational use limit the range of UAVs to the operator’s line-of-sight and restrict the areas in which they can be flown. Rules for commercial and governmental agencies are even stricter: the UAV and its pilot must meet the same inspection, maintenance and training levels as manned aircraft (Twidwell et al., 2016). Multiple agencies overseeing use of UAVs in conservation also complicates the matter.
The technology itself also has limitations. A UAV’s maximum airtime, altitude, range, and carrying capacity for sensors and cameras is limited by its size, power and battery life. Currently, the smaller vehicles suitable for restoration ecology applications have a range of less than 10 km and/or 2 hours, and fly at an altitude of 1 km or less. Expert pilots are needed if they are to be used in challenging terrain or weather conditions. Noise and vibration may be concerns in many research situations.
In conservation, UAVs have been used to conduct bird, reptile and vegetation surveys; to map tree canopy structure; and to collect water samples (photo from http://www.nutechventures.org).
Low-altitude aerial mapping and imaging can be used to determine distribution and abundance of vegetation, especially in sensitive or inaccessible habitats (Cruzan, 2016). It offers an unobtrusive means to monitor rare plant populations and ecological restoration progress. UAVs also offer developing countries an affordable means to map land cover, survey biodiversity, and monitor logging, mining and other illegal activities in conservation areas. They are particularly useful in tropical regions where cloud cover often obscures satellite images (Koh and Wich, 2012).
UAV’s have proved valuable in monitoring wildfires, but they can also be used in ecological restoration to ignite fires for prescribed burns, as this video demonstrates. [Harvest Public Media] (2016, May 11). Fire-starting drones? They’re here. [Video File]. Retrieved from https://youtu.be/GRnOAvAGTwM.
Besides lighting fires at restoration projects, UAVs could be used to monitor birds and other wildlife. For example, sandhill cranes came (or returned) to Deer Grove Forest Preserve in northeastern Illinois about five years into a prairie/wetland restoration project there. A pair nested, raised a chick, and returned as a family the next year. The cranes frequent a picnic grove near a model airplane flying field, so they have become accustomed to the noise of UAVs. That might offer a great opportunity to monitor them in their nesting area without imposing any human presence there.
Another recent scenario where a UAV, with skilled pilot, would have been useful was an unexplained occurrence of dirty water in a local creek tributary. As I walked upstream, the clear water suddenly became light brown and opaque. I followed the color to culverts underneath a major roadway, but was unable to determine where those culverts led or the source of the dirty water. Perhaps a drone could have flown through the culvert and found the source of the pollution.
Finally, UAVs have potential for seeding large restoration acreage. Volunteers broadcasting seed mixes by the handful works at Cook County Forest Preserve restoration sites which range from a few hundred to a few thousand acres, but larger restoration projects like Nachusa Grasslands or Midewin National Preserve might benefit from UAV-enabled seeding, such as depicted in this DroneSeed video. [DroneSeed]. (2016, Sept. 27). These drones plant seeds after forest fires. [Video File]. Retrieved from https://youtu.be/VpnuoUvGfQ8.