eDNA and Whole-Genome Sequencing: A Genetic Toolkit to Support Platypus Conservation

9 June 2026

Platypus populations have been hit extremely hard in recent years due to habitat destruction, particularly through reduction in river flows, and the rise in extreme weather events such as floods, droughts, and fire.

Leading researchers from the University of NSW Platypus Conservation Initiative suspect that in New South Wales and the Murray-Darling Basin, they are struggling to survive in highly fragmented regions. 

Amongst Australia’s leaders in platypus conservation expertise, EnviroDNA Senior Ecologist, Josh Griffiths, will be gathering at the 2026 Platypus Conference on Cammeraigal Country at Taronga Zoo in Sydney. At the conference, Griffiths is presenting how eDNA combined with genomic sequencing can help fill critical gaps in our understanding of population statuses.
 

Why the species listing matters

In 2021, the platypus was officially listed as Vulnerable under Victoria’s Flora and Fauna Guarantee Act. Griffiths, alongside many fellow researchers, contributed to a growing body of evidence that helped convince Victorian conservation authorities that the platypus was in decline enough to warrant legal protection. 

The push for platypus to be listed as threatened Nationally is important because it provides stronger legal protection and increases the chance of further population declines. 

Governing bodies require a rigorous dataset to demonstrate the species warrants listing. Critically, there needs to be a threshold of a 30% decline over three generations for the government to consider a species as threatened. However, this scale of data that has been largely unavailable for platypuses.

Platypuses are notoriously difficult to study in the wild due to their widespread and sparse distribution, and their aquatic and mostly nocturnal habits. This lack of data available on this species, hampers the ability to fully understand their conservation status. 
 

Genetic technologies for platypus populations

EnviroDNA has been building a spatial database of platypus distribution since 2016 with eDNA. We've generated more than 20,000 data points through our partnerships, documenting platypus occurrence across their range over the past nine years using eDNA monitoring. 

These projects include collaborating with Melbourne Water on a three-decade-long monitoring program, with eDNA complementing and expanding on traditional ‘capture and release’ methods. Sampling was undertaken at 1,800 locations across Melbourne’s creeks and waterways between 2021 and 2023 with platypuses found in dozens of creeks and rivers throughout Greater Melbourne. 

And, in response to the devastating bushfires during the summer of 2019/20, we partnered with Cesar Australia to undertake a broadscale eDNA survey funded through the Australian Government Regional Bushfire Recovery for Multiregional Species and Strategic Projects Program to quantify the potential impacts on platypuses in NSW using landscape-scale occupancy data. 

These surveys use a highly sensitive and specific qPCR assay designed to detect platypus DNA in water samples. This approach provides an efficient, non-invasive, and cost-effective method for environmental monitoring. With the combination of whole genome sequencing, it’s now possible to gain insights into historical effective population sizes and long-term population trends of platypuses. Cesar Australia, sister company of EnviroDNA, conducts whole genome sequencing for native species. These techniques enable a calculation of effective population sizes trends extending back thousands of years. 

Together these approaches provide the capacity to undertake a comprehensive assessment of platypus conservation status at both national and state levels using eDNA and whole genome sequencing. Never in history, have we been in a better position to understand the distribution of platypuses in our waterways and guide their conservation. 

We look forward to the 2026 Platypus Conference to join discussions on the future of platypus and share important research to help give them a fighting chance in the wild. To learn more, contact Josh Griffiths at: jgriffiths@envirodna.com