Date of Award
2024
Document Type
Thesis
Publisher
Edith Cowan University
Degree Name
Master of Science by Research
School
School of Science
First Supervisor
Robert Davis
Second Supervisor
Eddie van Etten
Third Supervisor
Michael Craig
Fourth Supervisor
Michael Lohr
Fifth Supervisor
Boyd Wykes
Abstract
Call playback is a survey methodology that has conventionally been used for the Australian Masked Owl (Tyto novaehollandiae), but it has ethical concerns and limitations. I aimed to address some of these issues by developing and trialling a bioacoustic survey methodology for the species in southwestern Western Australia. This survey methodology integrates passive acoustic monitoring and acoustic recognition software and holds certain advantages over call playback.
Using passive acoustic monitoring, we studied Australian Masked Owl behaviour around active nesting sites to determine patterns of calling behaviour. The species demonstrated higher levels of spontaneous vocal activity in autumn compared to spring. More vocalisations than expected were detected near ecotones of forest and open ground, indicating the species utilises features of this specific type of habitat. We suggest that Australian Masked Owl visit these areas frequently for hunting purposes as the structure of the habitat of these ecotones facilitates hunting, noting that this behaviour has been previously recognised and discussed in literature. Seasonal patterns in vocal activity showed some similarities with the few other studies on the spontaneous vocal activity on the species, but comparisons of our results with research on the behaviour of other Australian Masked Owl populations indicated that there is variation in breeding seasonality between populations and subspecies. We also detected behaviour such as courtship, and identified other patterns of vocal activity such as the species’ tendency to call closer to dawn and dusk, which may have implications for passive acoustic surveys.
Passive acoustic surveying was successful in detecting the species in areas where its presence was unknown, particularly in autumn when we observed a higher detection rate than call playback methodology did in the same season. However, in spring, passive acoustic surveying was ineffective at detecting the species yet call playback surveys remained moderately successful, and did not show any variation in seasonal detection rates. We suggest that the behavioural processes that influence the success of either methodology are different.
We investigated the relationship between Australian Masked Owl detections and environmental variables, and found a significant negative correlation between detections and the distance from survey point to forest edge, consistent with the premise that the species frequently occurs at or near ecotones. We also observed a negative correlation between detections and the distance to permanent water bodies, which may have been due to the species’ habitat requirement of large hollows for nesting.
The study demonstrated how passive acoustic monitoring can be used as both an effective survey methodology and behavioural research tool for the Australian Masked Owl. We discussed some of the behavioural process that appear to influence levels of spontaneous vocal activity, emphasising that understanding and considering the behaviour of the species may improve the bioacoustic methodology further. We concluded with future recommendations for research on the species.
DOI
10.25958/qgg4-vf49
Access Note
Access to this thesis is embargoed until 23rd January 2026
Recommended Citation
Yaschenko, N. (2024). Developing and applying a bioacoustic survey method for the Australian masked owl (Tyto novaehollandiae novaehollandiae) in Southwestern Western Australia. Edith Cowan University. https://doi.org/10.25958/qgg4-vf49