Charles E. Dortch

Devil's Lair, an example of prolonged cave use in south-western Australia

Abstract Long‐term investigations at Devils Lair, a small limestone cave in the Capes Leeuwin‐Naturaliste region of extreme south‐western Australia, have yielded archaeological material radiocarbon dated 6,500–33,000 B.P. Several occupation features show that people lived in the cave from 12,000 to 27,700 B.P. The cave deposit contains very rich assemblages of animal bones probably contributed by both human and animal predators; criteria are suggested to distinguish those bones and other remains representing human exploitation. A distinctive series of carbonate encrusted bones and stones present in the lower half of the deposit, including artefacts and the bones of extinct marsupials, is tentatively considered to be redeposited from unexcavated parts of the cave deposit whose minimum radiocarbon age is 37,750 ± 2,500 B.P. A wide range, though limited number, of stone and bone artefacts including debitage suggests that the cave was occasionally used as a campsite where culinary and maintenance activities ...

New perceptions of the chronology and development of Aboriginal fishing in south-western Australia

Abstract Aboriginal fishing in south‐western Australia was significantly affected by Late Holocene physical and biological changes along this regions l,600km‐long littoral. About 4000 BP sedimentological processes, in part generated by climatic factors, altered coastal configurations and estuarine hydrologies, blocking marine lagoons from the sea and causing partial filling and seasonal barring of estuary floors and entrances. These geomorphological changes affected most of the regions estuaries, and intensified seasonal differences in their salinity levels, which, combined with seasonal barring, restricted movements of school fish populations, thus compelling shifts in fishing strategies. Review of palaeogeographical and palaeontological data and investigation of former tidal weirs, on the shores of now nearly tideless estuaries and relict marine bodies, gives insight into the chronology of fishing and into the ways this key subsistence activity may have been adapted to changes in estuarine and coastal...

Rottnest and Garden Island prehistory and the archaeological potential of the adjacent continental shelf, Western Australia

For several decades Quaternary investigators have examined the geology and fossil record of Rottnest Island, 19 km offshore Fremantle, Western Australia, and, more recently, have searched the island for evidence of prehistoric human occupation. My own sporadic searches over the past 12 years, including a weeks examination of deflation surfaces and other likely find-spots in August 1990, have yielded only two stone artefacts. These are as yet the only finds attributable to a human presence on Rottnest prior to its being cut off by glacio-eustatic sea level rise, c .7000 BP ( Churchill 1959; Playford 1983). This paper reviews relevant finds from Rottnest Island, as well as ones from Garden Island 19 km south-south-east, and from the adjacent mainland coast, and assesses the archaeological potential of this part of the submerged continental shelf. Â

Test excavation at the Oyster Harbour stone fish traps, King George Sound, Western Australia: An investigation aimed at determining the construction method and maximum age of the structures

Abstract Several stone structures on the northern foreshore of Oyster Harbour, King George Sound, Western Australia, are documented in ethnohistorical accounts and traditionally regarded as ‘fish traps’ maintained and used by resident Aboriginal groups, around the late eighteenth-early nineteenth century. Test excavation at one structure (‘Trap 7’), undertaken at the request of the local Aboriginal community, did show the structure’s mode of construction, though failed to uncover datable materials in incontestable primary position whose radiocarbon age would show when the structure was built. The age of this structure’s original construction and fi rst use remains unknown, though it and other structures at this site presumably post-date mid-Holocene sea-level rise to present height, as is the case with other stone weir or trap complexes on the Southern Ocean coast.

Preliminary Underwater Survey for Rock Engravings and other Sea Floor Sites in the Dampier Archipelago, Pilbara Region, Western Australia

Abstract The paper presents the initial results of a project that aims to investigate the antiquity of human occupation of Australian tropical rainforests and the role that toxic plants played in the adaptation process. International research suggests that people only permanently occupied rainforests in the last 5000 years with access to agriculture. The fact that Australian rainforest Aborigines were hunter-gatherers using specialised processing technology to exploit toxic plant foods and living at high population densities suggests a more complex situation. These groups differed significantly from their neighbours in the semi-arid and arid zones who have until recently, provided ethno-archaeological models for explaining past Aboriginal behaviour and the bases for regional archaeology. On the other hand almost nothing is known archaeologically about the adjacent rainforest groups because little work has been undertaken to investigate the temporal and spatial nature of these societies and the affect of changing rainforest ecology over the past 35,000 years. This research begins this process.

Aboriginal Occupation on Rottnest Island, Western Australia, Provisionally Dated by Aspartic Acid Racemisation Assay of Land Snails to Greater than 50 Ka

The generally accepted age for the earliest human occupation of Australia is about 60,000 years (e.g. Chappell et al. 1996), with many dates centred around 30,000 to 40,000 years (e.g. Pearce and Barbetti 1981; Dortch 1984; Allen and Holdaway 1995; Dortch and Dortch 1996). Recent, but disputed, archaeological evidence at Jinmium in the Northern Territory indicates a much earlier date of occupation of 116,000 years (FuUagar et al. 1996; Spooner 1998) in line with palaeoecological evidence (e.g. White 1994; Roberts and Jones 1994; Thome etal. 1999). We present independent evidence from Rottnest Island, Western Australia, which provisionally suggests a Late Pleistocene (and possibly Last Interglacial?) age for Aboriginal occupation in Western Australia.