Perth researchers are using motion sensor cameras in urban backyards to better understand the lives of quendas in the city.

Anecdotal evidence suggests quendas, also known as southern brown bandicoots, are regular visitors to gardens around Perth.

Scientists at Murdoch University have partnered with the City of Mandurah to search for hard proof.

They have recruited residents to a project which places cameras in backyards to learn more about the movement and behaviour of quendas.

Dr Catherine Baudains from the university's School of Veterinary and Life Sciences told ABC Radio Perth that people might not realise they had them in their yards.

Sorry, this audio has expired Mandurah backyards could provide vital clues about quendas

"It is very commonly mistaken for rats in the urban area.

"A lot of the people I have spoken to in the last five weeks have said the first time they saw one they thought they had massive rats."

How to spot a quenda

They may look like giant rats, but there are important differences.

"They are small, brownish-coloured marsupials," Dr Baudains said.

"They have a rounded backside, shorter tails than rats, and a much longer, pointier nose, but often they are moving quite quickly so people don't get a good glimpse.

"Even around Murdoch University we had some issues with local residents putting out rat poison, and of course quendas can take the rat poison and it can kill them."

A friendly quenda in Glen Forest in the Perth Hills. ( Supplied: Robyn Cain )

ABC Radio Perth listeners reported seeing and interacting with quendas all over the suburbs.

Helen: "First time I saw one was in a local cafe in Parkerville and I screamed because I thought it was a rat — not sure who got the biggest fright."

Kimberley: "There are loads of them here in the kennel zone in Canning Vale. Love these little critters."

Ken: "Up here on the Kalamunda/Gooseberry Hill boundary, we have had quendas visiting for a number of years. This year, however, we seem to have at least seven which come to eat birdseed at our back door. "They also like mince, which we offer some magpies, to the extent of coming up to us and eating out of our hands on occasions. Love them."

Jane: "We had quendas when I lived in Willetton. We used to put rolled oats out for them at dusk so they didn't dig holes in our front lawn. "I took loads of photos, and they didn't seem to mind me hiding behind the dustbins and the flash going off."

Helping quendas before they are at risk

While the quenda is not considered endangered, Dr Baudains said it was important to understand how urban sprawl and the loss of natural habitat had affected them in order to avert potential threats to their population.

"If we can find those things out then we can give advice on what you can do to better provide for them in our human environments," she said.

"For any urban wildlife, there are always going to be challenges.

"People ask why don't they just stay in the reserves? Well, that's like saying all of the southern region of Perth should go shopping in just one supermarket."

Camera tracking in backyards will show what the quendas do, eat and how long they stay.

"Some of the images we have from the motion sensor cameras include a cat and a quenda sharing the same food," Dr Baudains said.

The quenda's pointy nose, digging and an appetite for fungi, could be helping the bush to thrive. ( Supplied: Hayley Davis )

Quenda are 'urban ecological engineers'

Researchers are also keen to show how quendas are helping the natural environment thrive.

"There appears to be a relationship between the presence of quenda in reserves and the effectiveness of regrowth, particularly of tuart trees," Dr Baudains said.

"One of our scientists calls the quenda 'urban ecological engineers'. Because they are digging mammals, they play a really important role in soil health."

She said they acted to help direct water into the soil, and because West Australian soils could be very hydrophobic — they repel water — it helped improve soil quality.

"They also dig for bugs and worms and microorganisms and they eat fungi."

The scientists suspect that the fungi diet may be reason quendas are helping with tree regrowth.

"When you have healthy fungi in the soil you have healthy plant growth," Dr Baudains said.

"The quendas actually help to spread that fungi, a bit like bees."

The backyard research is limited to homes in the City of Mandurah, and while enough households are enrolled for now, the team will recruit again in four months.