Flushed by its biggest flow in almost two decades, the Paroo River in northern NSW inundated up to 8000sq. km of ephemeral floodplain habitat in 2008. The Paroo is the last river in the Murray-Darling Basin that still runs its natural course, unfettered by major dams, weirs or diversions.

There’s always something for children to do on a big pastoral property, but for the Kaluder boys – Damon, then 15 (above, right), and 13-year-old Jared, left, the recent flooding on Naree station, 130 km north-west of Bourke, has temporarily expanded life’s recreational possibilities. “This water’s like having a beach nearby!” Damon exclaims. “It’s like nothing we’ve ever experienced before.

Researchers believe the river red gum, the most widespread eucalypt species on the NSW floodplains, could have a natural life span of 500-1000 years. Deep ‘sinker’ roots with particularly well-developed water-transport capabilities aid survival between inundations.

Lake Wyara is often little more than a vast saltpan near the NSW-Queensland border, 1000 km west of Brisbane, but this year its waters have spread across 8 km. Its seagrass blanket fuels an ecological system that has attracted tens of thousands of waterbirds of up to 40 species.

‘Arid’ is the official definition of the vast Cuttaburra floodplain, in the far north-west margins of the Murray-Darling Basin, given its average annual rainfall of less than 300 mm. In 2008, it had the soaking of the century, swelled by water from Queensland via the Warrego River.

Thousands of dehydrated amphibians, including this salmon-striped frog, emerge from underground refuges as the floodwaters rise. This semi-arid frog species reproduces rapidly after rain, each female laying up to 1500 eggs at a time in a floating foam nest.

Amphibians are among the few larger animals that remain in the Murray-Darling’s ephemeral feeder rivers as they dry up. Most are burrowing and water-holding frogs, such as the crucifix toad (above), that survive in tunnels below the surface.

“They’re related to some of the African frogs which can do similar sorts of things,” explains Dr Arthur White, president of the NSW Frog and Tadpole Study Group. “Although in terms of capacity to stay below ground, the Australian frogs leave them for dead!”

Pelicans usually nest on Lake Wyara, 3km from freshwater Lake Numalla, but in 2008 optimal conditions saw 15,000 breeding pairs nest on Numalla. Unlike Wyara, Numalla rarely dries completely, remaining an important refuge for migrating waterbirds.

PhD student Kate Brandis (at right) and NSW National Parks and Wildlife Service ranger Michael Mulholland document the straw-necked ibis breeding colony at Narran Lake Nature Reserve. Kate’s findings will aid the management of this globally significant site.

Hectares of lignum, a drought-tolerant shrub, attract breeding ibises, mostly straw-necked, to the Narran Lake Nature Reserve. The birds flatten dry stems to form nests protected from land predators by water. Lignum appears dead during drought, but when flooded, springs to life.

Under the shade of a coolibah tree. Floodwaters in the Cuttaburra Basin appear tranquil at sunset, but these wetlands churn day and night with invertebrates, including tiny crustaceans, molluscs and insect larvae. Coolibahs are most common in the north and west of the Murray-Darling Basin.

For a few short months, large parts of the outback have been transformed from a dry, seemingly lifeless expanse of rocks and dust, sparsely vegetated by stunted plants, to huge oases rippling with life.

It’s wondrous enough seeing water, kilometres of it in all directions, near the middle of Australia. But the spectacular explosion of life these rivers trigger when they flow is truly awe-inspiring.