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

Emmeline Bernadette Barrett Norris; Yiyin Chang; Stephen Jackson; Conrad J. Hoskin

doi:10.1071/AM25029

RESEARCH ARTICLE (Open Access)

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

Emmeline Bernadette Barrett Norris

^A ^* , Yiyin Chang ^B , Stephen Jackson ^C ^D ^E and Conrad J. Hoskin ^B

+ Author Affiliations

- Author Affiliations

^A James Cook University, College of Science and Engineering, Cairns, Qld 4878, Australia.

^B James Cook University, College of Science and Engineering, Townsville, Qld 4811, Australia.

^C Australian Museum Research Institute, 1 William Street, Sydney, NSW 2010, Australia.

^D School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW 2052, Australia.

^E National Museum of Natural History, Smithsonian Institution, Washington DC 20013-7012, USA.

^* Correspondence to: emmeline.norris@my.jcu.edu.au

Handling Editor: Ross Goldingay

Australian Mammalogy 47, AM25029 https://doi.org/10.1071/AM25029

Submitted: 7 July 2025 Accepted: 9 September 2025 Published: 30 September 2025

© 2025 The Author(s) (or their employer(s)). Published by CSIRO Publishing on behalf of the Australian Mammal Society. This is an open access article distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND)

Abstract

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.

Keywords: arboreal mammal, fauna survey, Petauridae, population monitoring, presence–absence, remote sensing, RPAS, UAV.

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