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RESEARCH ARTICLE (Open Access)
Contents Vol 47(1)

Drone surveys cause less disturbance than ground-based surveys in endangered spectacled flying-foxes (Pteropus conspicillatus)

Emmeline Bernadette Barrett Norris https://orcid.org/0000-0002-9825-5380 A *
+ Author Affiliations
- Author Affiliations

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

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

Handling Editor: Stuart Cairns

Australian Mammalogy 47, AM25010 https://doi.org/10.1071/AM25010
Submitted: 26 February 2025  Accepted: 19 March 2025  Published: 3 April 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

Robust population estimates are critical for detecting biodiversity declines. Thermal drones offer a promising alternative to invasive, imprecise ground-based techniques for monitoring endangered spectacled flying-foxes (Pteropus conspicillatus). This study evaluated spectacled flying-fox behavioural responses to drones to address concerns that they will disturb roosting colonies. At two studied roosts, drones elicited minimal disturbance, whereas ground-based surveys triggered alarm and escape responses, particularly among unhabituated flying-foxes. These findings highlight thermal drones as a non-invasive tool for monitoring spectacled flying-foxes. Further research is needed to evaluate their accuracy and precision compared with ground counts.

Keywords: animal behaviour, Chiroptera, conservation, Old World fruit bats, Pteropodidae, RPAS, thermal infrared, UAV, wildlife monitoring.

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