Feasibility of nocturnal thermal drone surveys for detecting endangered mahogany gliders (Petaurus gracilis) in tropical lowland woodlands

Reliable detection methods are essential for monitoring threatened species. Yet detection remains challenging for low-density populations of nocturnal, canopy-dwelling mammals. The endangered mahogany glider (Petaurus gracilis), endemic to lowland woodlands in north Queensland (Qld), Australia, is difficult to survey using conventional survey methods, which can be labour-intensive and yield low detection rates. We tested the feasibility of using thermal drones for detecting mahogany gliders by conducting four consecutive nocturnal flights over a 64-ha woodland fragment that supports a high-density population. Six individuals were detected within 2 h while flying the drone 10–30 m above the canopy and using oblique camera angles. We identified gliders in thermal imagery by their size, long tail and gliding behaviour, with no visible disturbance observed. These preliminary results indicate that thermal drones can detect mahogany gliders under certain conditions. With further validation, this approach could complement existing techniques for presence–absence surveys, population assessments and behavioural observations.