Estuarine Development and Human Occupation at Bobundara Swamp, Tilba Tilba, New South Wales, Australia

In Australia little direct information about past human activity has been obtained from wetlands, but they are a valuable archive of change through time against which the archaeological record from middens and rock shelters can be compared. The constant movement of small bands of hunter-gatherers has meant that there is little sign of intensive occupation, and the use of wetlands lay in their attraction as sources of water, plant foods and water birds, for which little archaeological trace can be expected. Moreover, since Australia is generally warm and dry, peat accumulations are rare and often oxidised, leading to poor preservation of features and artefacts. One exception to this, however, was the discovery of boomerangs and digging sticks preserved by peat in South Australia (Luebbers 1975). The infilled estuaries and barrier-dammed swamps of the relatively humid southern coast of New South Wales and eastern Victoria include many significant peatlands. The continental shelf of southeastern Australia is narrow and stream valleys are incised well below modern sea-level (Chapman et al. 1982). The coast of southern New South Wales has a poor sediment supply and consists of quartz sand beaches and low cliffed headlands. There is a microtidal regime that maintains stable water tables so that the lakes and swamps have persisted since the early Holocene. There are few large streams on this coast and open river estuaries are rare. Instead there is a spectrum of sand barrier-impounded saline lakes through to freshwater swamps behind beach ridges or dunes. In many areas the swamps provide the only access to freshwater at the coast, the streams feeding them being some kilometres inland. This paper reports on a combined archaeological survey and study of vegetation history from Bobundara Swamp, a major coastal peatland (Fig. 21.1). The swamp basin sediments have been dated and analysed to provide the chronology of local environmental change to set against the archaeology. A preliminary analysis of an offshore section (Narooma 3b) provides a more general history of environmental change in the area after 14,000 BP.