"New" populations of endangered northern quolls (Dasyurus hallucatus) and threatened golden-backed tree rats (Mesembriomys macrurus) have been found on the offshore Kimberley island Buckle Head.
Scientists also detected a bandicoot via infra-red camera.
Survey zoologist Dr Lesley Gibson says it appeared to be either a northern brown bandicoot (Isoodon macrourus) or a threatened golden bandicoot (Isoodon auratus).
"We're not quite sure which species it is because we didn't trap it," she says.
A team of two Balanggarra Rangers and four Department of Parks and Wildlife scientists conducted an 18-day wildlife survey at three locations.
These were Buckle Head near the mouth of the Berkeley River, a mainland site just opposite, and Lacrosse Island at the mouth of the Cambridge Gulf.
All are in the Berkeley sub-region of the Northern Kimberley.
"That particular sub-region is poorly known for its biodiversity values," Dr Gibson says.
"There's been essentially no surveys done in that particular part of the world.
"We wanted to find out what plants and animals occurred … also if there were any invasive weeds.
"The mainland site we hope is a starting point for future survey work, so that region will be better known in terms of its biodiversity values."
She says they had five nights of sampling at each of the sites before a helicopter transferred them to the next.
At each site they set traps, wildlife surveillance cameras and devices to record bat calls.
They established plant quadrats and recorded all the plant species within the quadrat.
"We made significant finds," Dr Gibson says.
"On Lacrosse Island we recorded common rock rats [a native species] and prior to our survey mammals had not been detected on that particular island.
"Because it sits in the Cambridge Gulf this island is visited by people who are going out fishing from Wyndham.
"We thought that it might be quite a weedy island but in fact Passiflora was the only confirmed weed species that we recorded on the island, although plant identifications are still ongoing.
"It has quite a substantial wetland on it which still had water in it when we were there."
She says it had a variety of waterbirds not often recorded on other Kimberley islands and a good diversity of reptiles for a small island.
"We now have quite a lot of information regarding the species that occur on these islands, albeit it's still a very small survey window," she says.
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