Coastal occupation before the “Big Swamp”: Results from excavations at John Wayne Country Rockshelter on Barrow Island

In this paper, we present a terminal Pleistocene/early Holocene archaeological record from John Wayne Country Rockshelter (JWCR), located on Barrow Island in north-western Australia. The rock shelter was used between 15000 and 7000 calBP, and provides insights into how Aboriginal people interacted with a changing coastal landscape throughout postglacial sea-level rise. The faunal record reflects this fluctuating local landscape. The late Pleistocene faunal assemblage largely consists of arid plains terrestrial fauna, and then transitions to a diverse marine invertebrate taxa midden. This record demonstrates coastal resource use throughout the terminal Pleistocene, before the expansion of mangrove forests across northern Australia. The stone artefact assemblages indicate varied expedient reduction patterns. The assemblages include artefacts manufactured from local limestone and non-local sources. Our analyses indicate that occupation durations at JWCR were longer during the late Pleistocene compared to the early Holocene, when productive mangrove environments became proximal. The implications of these results are twofold. First, effective use of coastal plain environments was probably just as important for coastal occupation as marine resource procurement. Second, the presence of relatively dense marine faunal assemblages is not necessarily a reliable proxy for individual coastal-site occupational intensity under conditions of local resource productivity.