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RESEARCH ARTICLE (Open Access)
Contents Vol 47(2)

Environmental variables that influence platypus (Ornithorhynchus anatinus) eDNA detection: an insight into eDNA study design for platypus occupation

Breony Webb https://orcid.org/0009-0003-4517-2383 A * , Nakia Belmer A and Adrian Dickson A
+ Author Affiliations
- Author Affiliations

A New South Wales Government, Department of Climate Change, Energy, the Environmental and Water, Lidcombe, NSW, Australia.

* Correspondence to: breewebb04@gmail.com

Handling Editor: Ross Goldingay

Australian Mammalogy 47, AM24028 https://doi.org/10.1071/AM24028
Submitted: 13 August 2024  Accepted: 24 June 2025  Published: 28 July 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 4.0 International License (CC BY).

Abstract

Surveying platypus, Ornithorhynchus anatinus, occupancy patterns presents significant challenges because of their elusive nature and the often-inaccessible environments they inhabit. Traditional methods, such as observer sightings and mark–recapture, are labour-intensive and limited in spatio-temporal coverage. Recent advances in environmental DNA (eDNA) technology offer a promising alternative, allowing for broader and less invasive detection of aquatic species. This study investigates the use of eDNA for detecting platypuses across various environmental conditions in Kosciuszko National Park, New South Wales (NSW), focusing on how abiotic factors such as altitude, stream order, and seasonal variations may influence detection probabilities. Sampling occurred over four seasons from November 2021 to May 2023 at 46 sites, including high-altitude and remote locations. Results indicated that eDNA successfully detected platypuses in previously undocumented high-altitude sites of NSW and showed significant influences of stream order, altitude and seasonality on detection rates. This research highlighted the potential of eDNA to improve platypus distribution knowledge and emphasises the importance of considering environmental factors in monitoring. Future studies should refine eDNA protocols to enhance reliability across diverse habitats.

Keywords: Alpine streams, Australia, detection, eDNA, environmental conservation, monitoring, platypus, semi-aquatic, survey methods.

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