For more than 20 years, Professor Chris Dickman has followed the extraordinary 'boom' and 'bust' cycle that characterises the Simpson Desert. He speaks of some of the challenges facing the plants and animals that inhabit the Simpson's pulsating expanse.

Professor Chris Dickman
Australia is mostly desert. Around seventy per cent of the continent is arid or semi-arid. Probably the most distinctive feature of the Simpson Desert is the long red, longitudinal sand dunes. People always assume it's going to be a barren, empty place with nothing there, and yet it's bursting with life.

My first trip to the Simpson was in January 1990. Initially we thought that we'd get out to the desert for five or six years. We thought that would be enough time to figure out how the desert system works. That was now nearly twenty-one years ago, and we're still finding things that we didn't even have a clue about.

Man
They're big, they're strong, they're feisty. They're the coolest thing out here. And he's a boy and he's peeing!

Professor Chris Dickman
The Simpson Desert has got an incredible richness of vertebrate species. You're looking at world records for numbers of species in a very arid area. Most action in the desert occurs during the, the night time. The animals seem to be very mobile, perhaps tracking food as it shifts across the desert landscape. Virtually all of the rodents eat a variety of foods. They'll eat insects, other invertebrates, green plant material, even a bit of fungus.
What we found in the first year was that many of the small marsupials are actually not digging their own burrows at all. They can't even dig - they just commandeer other animals' burrows.

One of the exciting things in the morning, you look forward to getting around the traps and seeing what you've caught. Have you caught another mulgara, have you caught a female with pouch young, have you got a desert mouse that you haven't seem for many years?

On every trip, we try to sample the food resources. We also look at the invertebrates, the things running around on the ground. We bring them back to Sydney and then count them to see what we've got.

Seeds are really the underpinning of all the life that we see in the central arid zone. It's all the cover, the shelter that the animals require, the great diversity of plants themselves. It's really absolutely crucial that we know more about these things.

You can get long periods of very dry conditions, and then maybe after a run of four or five years, you'll get a very big rainfall. After a big rainfall event, the desert transforms. You get this huge pulse of life. The annual grasses come up, the shrubs will begin to flower. Mammals will breed. As the small mammals are doing well, so too are the foxes and the cats.

This is a cat dropping that's now fairly dry. You can actually see that it's full of mammal hair. We found one cat that had six hopping mice in its stomach, plus around fifteen or sixteen dragons, a small snake, and two rats. Three species have disappeared from the trapping record. The small mammals have just been eaten to the point where they just have not come back into the dune system.

What goes on in the desert will often have quite big effects on people in the suburban areas. So we're looking at the responses of all the biota as far as we can, to the big rainfall events, the extended dry periods, to broad-scale wildfires - all of the ups and downs of climate.

We've got an opportunity to I guess, look into the future for other parts of Australia as it's happening in real time in the centre. One of the things that's kept me going back to the desert over all these years is that it's just a lovely place to be. It's just beautiful. You're away from the telephone, you're away from email. I guess with technology improving, it'll be possible to sit on top of a sand dune and send emails from there. But I don't think I want to know about that.

Story Contacts

Christopher R. Dickman
Professor in Terrestrial Ecology
The Institute of Wildlife Research
School of Biological Sciences
University of Sydney

Related Info

Chris Dickman Laboratory

Professor Chris Dickman awarded NSW Scientist of the Year for Biology

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