Recently, some of Australia’s leading ecologists completed a comprehensive review of the conservation status of Australia’s mammal species. The result is “The Action Plan for Australian Mammals” and the news isn’t good. Since European settlement, Australia has the worst mammal extinction rate of any continent, with almost 10% of our original mammal fauna now extinct. Of the remaining terrestrial mammal species (excluding bats), The Action Plan considers 30% at risk of extinction. 

The platypus is generally thought to have escaped the impact of European colonisation in Australia and as a result is not listed on any state (except South Australia where it was probably never very abundant or widespread), federal or international threatened species list. The IUCN (International Union for the Conservation of Nature) currently considers the platypus “a species of least concern”. The reason for this lack of concern is that the broad geographic distribution of the species has remained largely unchanged over the past 200 years. What worries platypus ecologists is the lack of population monitoring studies being conducted and the difficulty in reliably assessing population trends in this iconic species. Therefore the status of platypus populations across most of its range is largely unknown.

In revewing all the available information, The Action Plan has classified the platypus as Near Threatened. The authors identify a number of localised declines and fragmentation within the broader distribution and conclude an overall decline can be inferred from a limited number of population studies and predictions of threats to the species’ habitat. The authors also state that declines appear to be more severe in Victoria than other states. This concurs with cesar’s research that has demonstrated large declines and localised extinctions throughout the greater Melbourne area and Wimmera Catchment. The status of platypuses in other areas of the State is largely unknown due to a lack of effective monitoring programs but more extensive declines are likely. To make matters worse, the aquatic ecosystems that platypuses are dependent on, are expected to experience increased pressure under future climate change scenarios and human population growth.

It is vital that we understand the current state of Victoria’s platypus populations to provide a baseline to detect future changes. Live-trapping surveys are the most comprehensive way to assess platypus populations but are time and labour intensive and therefore difficult to achieve over large areas. Public sightings can help to determine occurrence and distribution of platypuses and local knowledge is invaluable to inform whether platypus may have declined or disappeared from your local waterway. Community members are encouraged to report past or recent platypus sightings to platypusSPOT.org or contact the platypusSPOT team directly (platypusSPOT@cesaraustralia.com) with general information of the status of platypuses in your local area.