Wildlife officers are scratching their heads after a dead carnivorous marsupial was found in the Perth metropolitan area, where the uncommon native species is not usually found.
The Department of Parks and Wildlife says the chuditch, or western quoll, was discovered on a footpath outside Bateman Primary School in the city's southern suburbs.
The animals live in the Perth Hills and WA's south-west, but populations are not known to live in built-up suburbs.
They can move long distances, however, so it may have travelled 20km or more from the hills along the Canning River using nature reserves as corridors, animal science program leader Keith Morris said.
"For it to have avoided predators such as cats and dogs, along with vehicles, for that distance would be remarkable," Mr Morris said on Tuesday.
"Another possibility is that someone who had been keeping the chuditch released it.
"The other option is that the species is still naturally occurring in the area, however, this is unlikely because there are no remnant bushland areas large enough to support a chuditch population."
The species probably inhabited the area until the 1950s when Bateman was still bushland and rural lots, Mr Morris said.
He said the two-year-old male was in very good condition and showed no signs of being predated, although it had a break in a rear leg, indicating it may have died after being hit by a vehicle.
Mr Morris has urged anyone with information about chuditch sightings in the metropolitan area to get in touch.