The Lake Hawdon System Important Bird Area comprises an area of 374 square kilometres (144 square miles) covering a series of five coastal lakes in the Limestone Coast of South Australia. They are the most important of a string of regional lakes occupying swale corridors between modern and historical sand dunes.

The Important Bird Area (IBA) lies between the towns of Robe and Beachport. It includes the following lakes listed in order from north to south - Hawdon, Robe, Eliza, St Clair and George, and the area extending for a distance of one kilometre (0.62 mi) inland from each in order to include habitat used by critically endangered orange-bellied parrots. Characteristics of the lakes are:

• Lake Hawdon – shallow, semi-permanent, brackish lake which is divided into a northern basin measuring six by six kilometres (3.7 by 3.7 mi) and a southern basin measuring nine by four point five kilometres (5.6 by 2.8 mi) with a maximum water depth of about one metre (3.3 ft);
• Lake Robe – 406 hectares (1,000 acres) much smaller than Lake Hawdon
• Lake Eliza – hypersaline coastal lake with maximum depth of 1.4 metres (4 feet 7 inches);
• Lake St Clair – 189 hectares (470 acres) similar to Lake Eliza but more saline
• Lake George – about thirteen by eight kilometres (8.1 by 5.0 mi) with maximum depth of 3.5 metres (11 feet); naturally hypersaline but functions as an estuary with an outlet to the sea.

The wetland system was identified by BirdLife International as an IBA because it regularly supports over 1% of the world populations of red-necked stint, and often of sharp-tailed sandpipers, double-banded plovers and banded stilts. It also provides habitat for orange-bellied parrots, Australasian bitterns, rufous bristlebirds and striated fieldwrens. The adjacent beaches and offshore islets, from Cowrtie Island to Baudin Rocks, sometimes support breeding fairy terns.

While the IBA has no statutory status, it does overlap the following protected areas declared by the South Australian government: Beachport Conservation Park, Lake Robe Game Reserve, Lake St Clair Conservation Park and Little Dip Conservation Park.

• List of birds of South Australia

37°16′34″S 139°55′35″E / 37.27611°S 139.92639°E / -37.27611; 139.92639