As the lake evaporates, only salt from the water remains — Lake Eyre is usually a salt flat, a white and barren landscape. When the lake does flood in rare heavy rains, the landscape is transformed. A kaleidoscope of colour blooms with wildflowers and wetland foliage, while waterbirds flock and endemic frogs and fish quickly appear.
Image: Peter Elfes. Because of the sheer size of our arid regions, knowledge of the deserts fauna continually shifts as new species are discovered. Over species of reptiles live throughout arid Australia — the most infamous is perhaps the desert death adder snake Acanthophis pyrrhus. Receive great savings and a gift when you subscribe to our magazine. Close Menu. Facebook Twitter Instagram Instagram Adventure. Popular this week A long way from home: Antarctic penguin makes it all the way to New Zealand New Zealand conservationists have released an adelie penguin back into the sea after the Antarctic-based bird swam thousands of kilometres to make a rare visit.
How climate scientists talk to their kids about the climate crisis We chat to three climate scientists from the University of New South Wales about how they talk to their kids about the climate crisis.
The desert also houses a few, scattered salt-water lakes. Indigenous Australians live in the area and follow a traditional way of life.
The Simpson desert occupies an area of , square km and occupies parts of Queensland, South Australia, and Northern Territory. These dunes are static and are held in place by vegetation. The 40 meters tall Nappanerica dune is the largest dune in the area. The water from the basin rises to the surface at a large number of natural springs distributed throughout the desert. However, since the desert is not accessible by any maintained roads and the summer temperatures here are extremely harsh, the government has closed the desert to tourists in summer to avoid unpleasant circumstances.
Drought resistant shrubs and grasses cover large sections of the desert. Fauna inhabiting the Simpson Desert include the water-holding frog, the Eyrean grasswren, the gray grasswren, etc. Several seasonal migrant birds can be spotted in the seasonal wetlands of the Simpson Desert like the Lake Eyre, the Coongie Lakes, etc.
Examples include the musk duck, glossy ibis, great egret, banded stilt, and others. The mound springs of the Great Artesian Basin also host several species of fish, invertebrates, and plants. The desert has a rocky terrain with small hills and is traversed by the Tanami Track. The important fauna species found here include the little native mouse, the long-tailed planigale, the Western chestnut mouse, the freckled duck, gray falcon, etc.
Several indigenous groups are also based in this desert. The desert encompasses an area of , square km and is surrounded by the Gibson Desert, the Great Sandy Desert, and the Tanami Desert. For instance, the climate of central Australia today probably represents the most favourable period in this desert since the end of the last interglacial about , years ago whereas the peak aridity of the last glacial maximum about 20, years ago marks the harshest conditions yet identified, with parts of the interior subjected to hyperarid conditions for a protracted period.
Changes in extent of the deserts The boundaries of these drylands have not been stable. The southern deserts have increased in size or contracted depending on shifts in global climate. In fact, the clearest evidence for environmental change is often from the margins of these deserts. For instance, fossil linear dunes occur well beyond the margins of the Australian arid zone, extending in southern mainland Australia into north-eastern Tasmania, and beneath King Sound in the north of Western Australia.
In Australia, the last glacial maximum was not just a time of more intense aridity, but also a period when deserts were more extensive. Changes in favourable patches within deserts Even within an arid or hyperarid landscape, external factors may selectively affect parts of the landscape. For instance, the reactivation of dry lakes in the Willandra region south west New South Wales or of the rivers feeding Lake Eyre e.
Coopers Creek , reflects changes in winter or summer rainfall systems outside the arid zone, and the transport of floodwaters into these regions. For instance, Lake Mungo one of the lakes in the Willandra system held water at various times between 15, , BP Endnote 4 , at a time when the surrounding landscape was more arid than today, because colder drier conditions produced more effective runoff in the southern highlands.
In about , people lived in the centrally located arid zone of Australia. The Australian semi-arid zone supported a further , people. All of the southern hemisphere deserts have remarkably long records of human settlement: more than 60, years in southern Africa, at least 35, years in Australia and about 13, years in South America. Current archaeological evidence suggests that the southern deserts were explored and colonised as part of the dispersal of modern humans across the globe.
In southern Africa, the first sustained use of the Kalahari took place about , years ago at about the same time that evidence for anatomically-modern and behaviourally-modern humans appears in the archaeological record. In Australia and South America, initial human movement into the deserts took place as part of dispersal across new continents, by people who had already demonstrated the capacity to undertake successful sea crossings Australia or cross extreme high latitude cold environments North America.
They are also environments where resources are patchy and highly variable in both time and space: In Australian and southern African deserts, where there are significant plant and animal resources thinly distributed throughout the desert, it is the distribution of watering points that determines which parts of the desert landscape people can reach and where and when they can harvest available resources, whether these be stone, ochre, plant foods or game.
Both the spatial distribution of these waters and the productivity of the surrounding country vary with rainfall. Rainfall events create unpredictable pulses of biological productivity, separated by long dormant periods. All of the southern hemisphere deserts were successfully settled by hunter-gatherers. For historic groups, the key adaptations for living in deserts were behavioural and social, rather than technological. They included high residential mobility, broad-spectrum foraging, a high degree of organisational and technological flexibility and intimate knowledge of the dynamics of the landscape.
One other factor is also important here. Human dispersal is likely to be constrained by the difficulty of maintaining viable social networks when population levels are very low as in most deserts. Historically, the Australian desert had some of the lowest population densities on record for human populations as low as one person per sq km.
Under such conditions, effective social networks are important. Early Stone Age Acheulian hunters followed game and water into these areas about , , years ago, wherever pans, springs or floodwaters provided accessible routes into the deserts.
The first human movements into the Australian deserts took place sometime before 35, years ago, probably as part of initial peopling of the continent. People come for the stunning scenery , magnificent rocks and gorges and coloured sands , the unique plants and animals in the desert. But also to experience the open spaces, quietness and solitude and to get away from the hustle and the crowds of the coastal cities.
Australia's cities, coasts and beaches are beautiful, no doubt about that. But what you find there can be found in other parts of the world as well. The deserts of Australia are unique. Nothing compares.
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