Palaeontologist Dr Arthur White looks for turtles in Louis Creek. This creek is home to many species not found anywhere else in Australia. Boodjamulla National Park, North West Queensland.PT3M31S http://www.canberratimes.com.au/action/externalEmbeddedPlayer?id=d-2sap0 620 349 August 21, 2013
''Come on, take off your clothes and get in.'' Scientist Arthur White is neck-deep in a murky creek about 200 kilometres north of Mount Isa, making me an offer I'd rather refuse.
The hot spring-fed creek is covered in a thick film of algae and is a likely home for a few crocodiles - a hazard that doesn't seem to bother Dr White. ''Don't worry, they'll only be freshies,'' he says.
By the time I lower myself into the silty water, he has disappeared below the surface in search of a less fearsome reptile, the endangered gulf snapping turtle.
Research: Arthur White in Louie Creek. Photo: Tony Walters Photo: Tony Walters
In the 1980s, Dr White was the first person to describe the species, but his study came from a specimen that had been buried for millions of years in the nearby Riversleigh World Heritage fossil site.
A decade later, scientists were surprised to learn the species was not extinct when a university student captured a live gulf snapping turtle in a nearby creek.
The experience struck Dr White as an embarrassing reflection of how little we know about our wildlife.
''We were in this silly situation where we knew the fossil fauna better than the modern animal fauna,'' he says. ''We'd described the gulf snapping turtle from a fossil at Riversleigh, but it was here swimming around the whole bloody time.''
This prompted Dr White to start an annual fauna survey. For two decades, the scientist and a team of volunteers travelled to Boodjamulla (Lawn Hill) National Park to catalogue the wildlife, spending up to six weeks a year surveying the animals.
The team have collected many species unknown to science, including reptiles, amphibians, insects and a variety of rock wallaby.
As part of the survey, the team started trapping turtles. Which brings us to the warm waters of Louie Creek.
There's a splash as Dr White dives below the surface. A minute later he's holding a Worrell's turtle, but he releases it when another animal gets his attention.
''There's a two-to-three metre croc under the bank over there,'' he says, pointing a few metres ahead of where we are treading water.
I take a breath and put my head below the surface. As my eyes adjust, I see the crocodile's long, narrow snout. It doesn't move.
We watch it for a few more minutes. Then it's time to go.
''Shall we swim back now?'' Dr White asks.
I'd rather walk, I say.