Lake Machattie fills about once every three years. The rest of the time it is a pale, cracked claypan in one of the driest corners of Queensland, where the average rainfall barely reaches 168 millimetres a year. Then the rivers come. Water that fell as monsoon rain hundreds of kilometres to the north arrives down the Georgina River and Eyre Creek, spreads across the floodplain through a maze of branching channels, and turns the desert into an inland sea. Within weeks the birds find it. More than 300,000 waterbirds have gathered here when the water is high, summoned across a continent to a place that, for most of its existence, holds nothing but sky and dust.
This 909-square-kilometre tract takes in three lakes, Machattie, Mipia and Koolivoo, woven through the floodplains of the Georgina and Eyre Creek systems in the heart of the Channel Country. Each lake keeps its own rhythm. Mipia and Koolivoo flood almost every year, with Mipia often holding water right through to the next flood season while Koolivoo dries by early summer. Machattie is the rare one, filling roughly once in three years. When the floods arrive the lakes run fresh, but as the water retreats and evaporates under the desert sun they turn slowly saline, a shifting chemistry that reshapes what can live in them from one season to the next. The channels themselves anastomose, splitting and rejoining, lined with open coolibah woodland above grassland, samphire and tangled lignum.
BirdLife International recognises Lake Machattie as an Important Bird Area, and the numbers explain why. When the water is high the wetland has held over one percent of the entire world population of several species at once, an extraordinary concentration in a single place. Freckled and pink-eared ducks arrive in their thousands. So do Australian pelicans, straw-necked ibises, royal spoonbills, little black cormorants, red-necked avocets and sharp-tailed sandpipers. The pelicans nest along the banks and feed in the flooded channels. To stand here in a wet year is to witness a kind of arithmetic that does not seem possible in a desert: hundreds of thousands of birds, drawn from a continent away, all converging on water that will not be here for long.
The same boom-and-bust that feeds the waterbirds shapes the species that never leave. The Australian bustard stalks the open grasslands, and the grey grasswren, a secretive bird of the lignum thickets, holds on in country that gives it cover and little else. After good rains the floodplain fills with movement: Australian pratincoles wheeling over the flats, black-tailed godwits probing the mud, and flock bronzewings arriving in the great numbers that earned them their name. Every one of them is keyed to the flood. Their breeding, their movements, their survival all track the unpredictable pulse of water down the channels, a calendar written not by the seasons but by rain that may have fallen in another part of the country entirely.
There is no better way to grasp the Channel Country than to see it filling. From the air the floodplain reveals its structure plainly, the silver thread of the Georgina and Eyre Creek splaying into dozens of channels that spread across the black soil like fingers, the lakes brimming where they pool. It is a landscape that makes sense only when you can see the whole of it at once. In a dry year you would fly over what looks like wasteland and never guess what it becomes. In a wet one, the desert below has turned to mirror and movement, and the air above the water is alive with birds. Few places change so completely, or reward the long view so richly.
The Lake Machattie Area centres on roughly 24.82 degrees south, 139.56 degrees east, in the Channel Country northwest of Birdsville. In flood it is unmistakable from the air, a sheet of water threaded by branching channels along the Georgina River and Eyre Creek; in drought it reads as pale claypan and cracked floodplain. A higher viewing altitude of 4,000 to 6,000 feet AGL best reveals the anastomosing channel pattern and the scale of the wetland. Nearest strips are Bedourie (YBIE) to the northeast and Birdsville (YBDV) to the south, with Boulia (YBOU) further north. Avoid low passes over nesting waterbirds in wet years; expect heat haze in summer and superb light and visibility after the floods recede into winter.