Waterwatch calls on volunteers to help out this Platypus Month

Platypus numbers across Australia are thought to be in decline, with a push to have the beloved natives added to the threatened species list.

Waterwatch ACT will partner with the University of Canberra in the count for the first time, using more sophisticated tracking methods to get the most accurate understanding of local populations.

Waterways ACT needs eager volunteers to help count platypuses at one of the 34 group surveys to be conducted across eight locations they're known to frequent.

With winter the ideal time to catch feeding platypuses as they bulk up for the breeding season, volunteers will be required to brave some early mornings or head out at dusk to spot them.

Waterwatch regional facilitator Woo O'Reilly said platypuses tended to be seen more frequently during periods of high rainfall when rivers were full.

"The feeling is there's likely more production in the rivers, there's more water bugs, there's more food resources for the platypus out there," she said.

"We certainly found in 2019 during a really dry year we saw less platypus across the board at every site."

Queanbeyan River, Point Hut Crossing and Tidbinbilla Nature Reserve are three prime locations for spotting the somewhat elusive mammal.

Ms O'Reilly said numbers in the ACT were thought to be relatively stable, however, platypuses often fell foul to discarded litter, as they swam blind.

Platypuses have skin flaps that cover their eyes and ears underwater, meaning there have been instances of them unintentionally swallowing fish hooks and drowning in the ACT.

Volunteers will also learn to identify rakali - better known as water rats - which also help provide an insight into the health of ACT waterways.

Ms O'Reilly said more work needed to be done to better understand the effect of dry years and long-term population trends.

"We're not just doing this to raise awareness about platypus, the data we collect is really important," she said.

"That's why we're working with UC this year to strengthen our confidence in the data and better apply it to great conservation outcomes for the platypus."

Ben Broadhurst, biologist at the University of Canberra, will lead a team heading out to a subset of sites with volunteers.

The UC team will capture and microchip some of the platypuses, as part of a "mark-recapture study", revisiting the site several times to check their numbers matched up with volunteer figures.

Mr Broadhurst said the technique would provide more confidence in looking back at observational data, some of which was employed up to 30 years ago in the region.

"River development, damming and abstractions have had an impact on platypus abundances in Australia," he said.

Platypus sightings can also be recorded through the Waterwatch website.