Possibility of applying unmanned aerial vehicle and thermal imaging in several canopy cover class for wildlife monitoring – preliminary results

Abstract

Tropical rainforests are one of the important habitats on earth but are rarely explored because they are difficult to access, making their cryptic animals challenging to monitor. Unmanned aerial vehicle (UAV) with thermal infrared imaging (TIR) technology is gaining entry into wildlife research and monitoring. The researcher tested the possibility of applying DJI Mavic 2 Enterprise Dual with FLIR as aerial survey platforms to wildlife in the five tree density classes in the IPB University Campus. To assess the effectiveness of using drones in detecting wildlife, the researcher measured the optimum flying height, sound level, temperature, and optimum flight time in each canopy cover class. The optimum height for animal detection is <50 m HAGL with a sound level that animals can still tolerate. Wildlife detected had body temperatures around 27 °C and were conspicuous in the thermal infrared imagery at night and early morning when the forest canopy was cool (15–27°C), but were difficult to detect by mid-day. By that time, the direct sunshine had heated up canopy vegetation to over 30°C. Species were difficult to identify from thermal infrared imagery alone but could be recognized from synchronized visual images taken during the daytime.

The first use of a photogrammetry drone to estimate population abundance and predict age structure of threatened Sumatran elephants

“…It has been acknowledged that drones have numerous benefits over traditional techniques 44 – 46 , and our recent research further validates the effectiveness of drone surveillance, especially in monitoring endangered biodiversity in remote areas that are rapidly experiencing land use change and disturbance. In recent studies, drones have been recognized as an innovative and valuable tool for conducting conservation research on many species across different types of ecosystems in Indonesian tropical rainforests, for example, drones for biodiversity surveys 36 , 47 , 48 , studying primate behaviour and waterbird population survey 36 , and we confirm the feasibility of this method for conducting non-invasive aerial surveys on the Sumatran elephant. This species is ideal for drone monitoring because it behaves and lives in groups—congregating in relatively open forest areas to feed and shelter under forest stands—and is highly visible from the air.…”