Environmental DNA assessment of platypus distribution in the Middle Barwon River incorporating grass- roots citizen science

www.friendsofthebarwon.org.au

Friends of the Barwon (FOTB), propose to investigate platypus distribution in the middle Barwon (Winchelsea to Fyansford) using environmental DNA detection and citizen science. Water samples will be collected and analysed for DNA from 50 sites along the waterway through a partnership with local community groups. Detailed project plan attached. his will establish platypus abundance and be a vital baseline for future studies. Environmental DNA species detection is a robust, relatively low cost and non-invasive technique ideally suited to this type of citizen science project. The partnering local river community for this project is represented by the Geelong Landcare Network. There is no current information for platypus distribution in this region, however, the middle Barwon is notable for having several large and very deep holes which may represent significant refuges for platypus populations. Previous studies: Over the last two decades the Barwon River has been severely impacted by reduced flows and then in 2016 there was a major fish kill as a result of highly acidic water from Boundary Creek impacting the upper Baron river. In recognition of these impacts Upper Barwon Landcare Network (UBLN) employed EnviroDNA in 2018 and 2019 to assist in the assessment of contemporary platypus abundance in the upper Barwon (West Barwon Reservoir to Winchelsea). The local river community were trained to collect samples and assess the condition of riparian vegetation at the sample sites. This tested methodology will be used for the proposed study of the middle Barwon.