Lake Eyre National Park
Kati Thanda-Lake Eyre National Park is in the Australian state of South Australia and is about 700 kilometres (435 mls) north of Adelaide. The lake was named after Edward John Eyre who, in 1840, was the first European to see it. In 2012 its name was officially changed to include the indigenous name, Kati Thanda, out of respect for the native title holders, the Arabana people, who have occupied the land for thousands of years. It is their sacred name for the flat saltpan and means ‘the name of the lake which was formed after the skin of a kangaroo was spread over the ground’.
The saltpans are up to 50 cm (20 ins) thick and became an international landmark in the 1960s when British speed racer Donald Campbell used the site to break the world land speed record, reaching 648kmh in his Bluebird racer.
The lake is actually two lakes connected by a channel. It is the lowest natural point in Australia and is around 15 metres (49 ft) below sea level at its deepest point. It is the largest lake in Australia, but one that is rarely filled with water. It is in the driest region of the country, with an annual rainfall of 100 to 150 mm (4 to 6 ins), but usually some water remains in a series of sub-lakes. In the rainy season rivers flow in from Queensland but travel as far as the lake only on rare occasions. It takes about six weeks for the water to flow from its source to the lake. Water covers the lake about once every eight years, but it has filled to capacity only three times in the last 160 years.
In dry times the park encircles a desolate landscape of saltpans and waterless tracts of red desert but after rain this usually stark landscape turns green with new plant life and, as the flowers develop, comes alive with colour.
When the lake is recently flooded and several metres deep the water is almost fresh and native fresh-water fish can survive in it, but as the salt dissolves, and the water evaporates, the fish die. Saturation point is reached when the water depth is around 50 cm (20 ins) and it is at this point that the lake often turns pink due to the presence of algae. When the lake is flooded it is a phenomenon that around midday the surface can become so flat and so perfectly reflective that the line between water and sky is almost impossible to distinguish. Local sailors say it is like ‘sailing in the sky’.
The lake is on the list of important wetlands of Australia and is an Important Bird Area (IBA) because when it is flooded it supports major breeding events of several species of birds. Pelicans are drawn to the lake from as far afield as Papua New Guinea. During the 1989-90 flood it was estimated that 200,000 pelicans, 80% of Australia’s total population, came to feed at Lake Eyre.