New archeological discoveries in Australia highlight lack of protections for submerged Indigenous sites

Based on marine bioregions and state, the study area is compared to Australia's main terrestrial and offshore areas. Contains GEBCO 15 ArcSecond raster information (Public Domain) as well as Maritime Boundaries Geodatabase : Maritime Boundaries & Exclusive Economic Zones (200NM), (version: 11). (CCBY 4.0). CS = Coral Sea; N = North; NW = North-West; SW = South-West; SE = South-East; TE = Temperate East. Credit: Australian Archaeology, Dr John McCarthy
New archeological research reveals major gaps in Australia's environmental management policies. This puts submerged Indigenous heritage at serious risk.

During a land and sea archeological survey of the Pilbara coast in Western Australia (WA), Deep History of Sea Country's (DHSC), project team discovered a new intertidal rock quarry and stone tool manufacturing location, as well coastal rock art, engravings and other evidence.

These findings were published in conjunction with a separate study on the Northern Territory that identified underwater environments dating back the Pleistocene. This could offer important environmental and cultural insight into ancient Indigenous migration, land usage and early occupation of Australia.

Today's findings in Australian Archaeology highlight the need for a national strategy to ensure resource companies protect Aboriginal heritage, develop protections against climate change and seabed mining, as well as collaboration with Indigenous stakeholders.

New evidence has been found of cultural heritage in Western Australia, where hundreds of ancient stone tools that were made by Aboriginal people submerged more than 7,000 year ago have been discovered. Although the team is still trying to determine the age of the sites located in the intertidal area and fully submerged channel, the results show a promising path forward for studying the integrated landscape above and beneath the waterline.

North Gidley Island. Insets: (Top Left) Large multiplatform core; and (Top Right) Quarried rock in the intertidal area; (Bottom Left) Quarried and artifact scatter; and (Bottom Right) Grinding patches and associated engravings within the quarry site. Credit: Jerem Leech, Flinders University

"The challenge now facing Australian submerged heritage" is Associate Professor Jonathan Benjamin, who coordinates the Maritime Archaeology program at Flinders University's College of Humanities, Arts and Social Sciences.

"We must better understand and manage the underwater cultural heritage using both local and national approaches. We must consider the very different scales of research, from 'big data' down to the boots-on-the-ground and snorkels-in-the-mouth as we comb Australia's coasts, intertidal zones and submerged environments to record new archeological sites. Submerged sites can be found all over the continent and at depths of up to 130 meters.

Flinders University, James Cook University and ARAAirborne Research Australia teamed up with the Murujuga Aboriginal Corporation in order to create new aerial and intertidal survey of the cultural landscape of WA.

The location of the study area is shown by the islands of Murujuga. The area of sub-aerially exposed ground. Copernicus Sentinel data 2016 for Sentinel data. Credit: Leach et al. in Australian Archaeology

We found evidence that North Gidley Island was home to a variety of cultural activities, including ancient seed processing, marine resource usage, rock art production, and ceremonial activities. It is difficult to date this variety of activities, but engravings and submerged material provide some clues that North Gidley Island was occupied in the terminal Pleistocene.

The dive team mapped 269 artifacts from Cape Bruguieres in 2019, at shallow depths of 2.4 meters below the current sea level. The site is more than 7000 years old, according to radiocarbon dating and analysis.

"Artifacts embedded into aeolianite offer an opportunity to understand at least some of those stone artifacts' age, which could be supported with excavation both on land and within the more sheltered and less sediment-rich intertidal areas north of Cape Bruguieres channel," said Distinguished Professor Sean Ulm, James Cook University's ARC Centre of Excellence for Australian Biodiversity and Heritage. He is also co-author of this study.

(Top left) Northwest North Gidley Island Quarry and Artefact Scatter; (Top right] Flake from North Gidley Island Quarry and Artefact Scatter; (Bottom Left) Northwest North Gidley Island Mobile Sands Aerial Photography from 2018; and (Bottom Right) Northwest North Gidley Island Mobile Sands Drone Imagery from 2019. Credit to Shaun Wright and Jonathan Benjamin

"The Gidley islands are a continuous cultural landscape that extends above and below the waterline. They tell the story about people responding to climate changes, which includes the re-negotiation landscape use between coastal and maritime communities, much as we see today with climate change."

"Rock art engravings and grinding patches, quarries, quarries, and upstanding stonesall of which are located in the intertidal areapoint to the possibility to discover new underwater sites in WA and Australia."

Flinders University's Dr. John McCarthy says that the northernmost part of the continental shelf is located in the Northern Territory coast. This area is of special significance because it lies between Australia and New Guinea during the first peopling of this continent, when the two landmasses were linked into one landmass called Sahul.

Aboriginal communities from the Northern Territory have recollected locations of oral traditions that may be connected to sea-level changes. Credit: Australian Archaeology, Dr John MccArthy. Topography and bathymetry taken from the SRTM30+ v 8.0 via eAtlas, CC BY 4.0

"We found that the submerged landscapes surrounding Darwin and Bynoe harbours offer varied, partially sheltered environments with maximum accessibility of facilities for fieldwork. The Tiwi Islands, Wessel Islands, and the Gulf of Carpentaria's Groote Eylandt, are some of the more remote areas that could be used for prospection. These islands, along with the Sir Edward Pellew Islands in the Gulf of Carpentaria and Groote Eylandt, offer opportunities through erosion of sediments.

"Our Northern Territory study highlighted a gap in marine management in the country. Submerged archeological landscapes have not been included in nationally-coordinated studies on marine biology and shipwreck heritage. This study provides a template for baseline studies at the state level to expand national search for submerged landscapes.

Dr. McCarthy received an ARC Discovery Early Career Researcher Award. This award was given to Dr. McCarthy to help develop machine learning tools that will reduce the costs of searching for submerged landscapes.

Groote Eylandts topography from a perspective. This is how it looked at 12,000 years ago. This document contains GEBCO 15 ArcSecond Raster data (Public Domain). Credit: Dr John MccArthy, Australian Archaeology. GEBCO 15 ArcSecond Raster Data (Public Domain).

Two possible portable grindstones were found in submerged conditions in the Cape Brügieres channel. Credit: Jonathan Benjamin and Hiro Yoshida

Scientists believe there was 2 million more square kilometers of coastal plain in the last Ice Age than today. The larger coastal lands that now form Australia's underwater continental shelf will likely contain many important archeological sites.

Submerged cultural landscapes are what many Indigenous Australians call Sea Country today. They have a deep cultural and spiritual connection to these environments.

Further exploration of Aboriginal artifacts reveals first underwater cultural sites in Australia

More information: Jerem Leech et al., North Gidley Island's integrated cultural landscape: Coastal, intertidal, and nearshore archaeology at Murujuga (Dampier Islandipelago), Western Australia. Australian Archaeology (2021). Jerem Leach and colleagues, The integrated cultural landscape in North Gidley Island: Nearshore, intertidal, and coastal archaeology at Murujuga (DampierArchipelago), Western Australia. (2021). DOI: 10.1080/03122417.2021.1949085