CESAR senior wildlife ecologist Josh Griffiths – working with Wimmera Catchment Management Authority – surveyed the river overnight Tuesday and Wednesday.

He captured one platypus, at midnight on Tuesday.

“The interesting thing about this one was he’s at least two years old, which means he’s evaded our nets until now,” Mr Griffiths said.

“In the past few years we’ve consistently had a low number of catches, however we keep getting new animals into the population, which is a good sign it’s growing.

“The thing about platypus is that once you've caught them once, they tend to avoid your nets, so it's hard to tell if those animals you've caught before are still around or not.”

Mr Griffiths said the authority had ran the surveys since 2008.

“This is really the only platypus population that’s left in the Wimmera, which makes it highly significant from a conservation perspective,” he said.

“The CMA has a high priority on it, and hopefully we will see the population grow.

“Part of the critical actions for this population is the environmental flows CMA releases – that’s really been the only reason this population still exists.

“You can see the habitat and condition of the river is continually improving every year, which will hopefully see the population improve.”

Mr Griffiths encouraged Wimmera residents to become involved with the project.

“We’d love to tap into local knowledge, and we have a citizen program called platypusSPOT where people can submit sightings,” he said.

Mr Griffiths said people could visit www.platypusspot.org for more information, or download the platypusSPOT app.