Why can UAV+thermal imaging technology help wildlife investigation and protection?

Wild animals are an important part of natural ecosystem, and the protection of wild animals is related to global ecological health and safety. To protect wildlife, we must first investigate the population resources and understand the accurate species distribution, population size and habitat change. And provide scientific basis for further evaluating the quality of life of species, determining the protection level and formulating corresponding protection strategies. However, this important basic work is extremely difficult to achieve under the conditions of mountain forest areas.

A few days ago, the research team of Qinling Golden Monkey in the School of Life Sciences of Northwest University applied drone and thermal imaging technology to investigate the distribution and population size of wild Sichuan Golden Monkey in Qinling area. The research team collected thermal imaging videos of three groups of Sichuan golden monkey wild populations in the investigation area, and obtained the accurate distribution position and population size of these populations. UAV technology can overcome the limitation of terrain and vision, and thermal imaging technology can find individual animals through the temperature difference between animals and the environment.

1. UAV can fly quickly in the canopy, which can eliminate the problem of terrain and vegetation occlusion when the ground moves and realize free movement. At the same time, in practical work, the UAV can scan the investigation area at the speed of 15 ~ 20km/h, which greatly improves the investigation speed.

2. The aerial view of UAV has the characteristics of deep depth and wide viewing angle, which eliminates the problem of visual occlusion at low viewing angle; On the other hand, using thermal imaging technology, infrared thermal radiation is detected, not visible light. As long as there is obvious temperature difference between the body temperature of animals and the ambient temperature, animals that were originally hidden under the forest can appear. After discovering animals, researchers can observe the long-term movement of animal populations manually, which can effectively improve the timeliness and accuracy of population statistics. In addition, the trajectory information synchronously recorded by the UAV can confirm the coordinates of the population in time and provide objective evidence through surveying and mapping.

3. Drones can replace manpower to conduct investigations, which can reduce the safety risk of investigators going deep into mountain areas to conduct on-the-spot investigations; The non-contact characteristics of the thermal imager will also reduce the interference of the investigation itself to wildlife.

Looking back on the exploration road of the combination of the two technologies, He Gang said that it was not smooth sailing. He recalled that at first, the research team only thought of applying drone technology, but the test results were not satisfactory. Although drones can realize aerial observation, ordinary visible light lenses still cannot penetrate the dense forest canopy and find hidden animals. However, the maneuverability and the ability to overcome obstacles on the ground made the research team see the potential of its application. "Later, when we participated in the research on the temperature measurement of wild animals carried out by Shaanxi Qinling Key Laboratory for the Protection of Rare and Endangered Animals, we noticed the thermal imaging technology, which instantly opened up new ideas for our research." He Gang said.

He Gang shared that through a series of experimental tests, the research team gradually completed the applicability test of drones and thermal imaging technology in various terrain, habitats and altitude conditions. By constantly summarizing the test results and optimizing the UAV flight plan and camera shooting plan, the research team basically solved various problems such as the adaptation of camera resolution and flying height, the calculation of flying height and speed and investigation area, the interference of other heat sources on animal investigation, the safe take-off and landing in mountainous forest areas, etc., UAV recovery, the remote control transmission of UAV is blocked, the communication signal is attenuated, and the crosswind in the valley seriously threatens the safe flight of UAV.

"The combination of UAV and thermal imaging technology may be one of the best technical options for wildlife survey in mountainous forest areas. In theory, this technology will also have good applicability in other grasslands, deserts, waters and other environments. " He Gang said that due to the technical factors such as thermal imaging resolution and observation distance of drones, it is better to apply this technology in the investigation of large mammals (such as golden monkeys, giant pandas, takins, etc.). ).