16 October 2019

A deep shell midden created by Aboriginal people over thousands of years on a remote island off the coast of Queensland is helping researchers at the ARC Centre of Excellence for Biodiversity and Heritage (CABAH) to learn lessons about the human and natural history of the continent.

The two-metre deep midden on Dingaal country in the Lizard Island Group, is full of rich archaeological materials, such as turtle bones, fish bones, shells and stone artefacts. A transdisciplinary team led by CABAH Deputy Director and ARC Future Fellowship recipient, Professor Sean Ulm, and Professor Ian McNiven, has undertaken an intricate examination of the site, including high-resolution 3D laser scanned images. Their discoveries have the potential to help answer questions about the impact of people and the climate on past environments.

“These islands were only created around 10,000 years ago when sea levels rose,” explains Professor Ulm. “Understanding the landscape and how people and climate have transformed it, has implications for our understanding of how the Australian mainland landscapes were modified over tens of thousands of years.”

Professors Ulm and McNiven have long collaborated with Dingaal Traditional Owners on research in the Lizard Island Group, located 35kms off the coast of Far North Queensland.

“Our collaborative research with Dingaal Traditional Owners has shown that the Lizard Island Group was first occupied before 6,000 years ago,” Professor Ulm says. “That’s significant, not only because it is some of the earliest evidence we have for Aboriginal occupation on the islands of the Great Barrier Reef, but because it shows that, more than 6,000 years ago, Dingaal ancestors were using sophisticated watercraft technology and navigation abilities to reach these islands.”

The project aims to achieve a holistic understanding of how Dingaal people engaged with their land and seascapes over very long time periods. But the results could have implications for the investigation of the human and natural past of the Australian continent as a whole.

“We know that Aboriginal people dramatically transformed their countries through careful management, including using fire, plant production techniques and building structures such as fish traps and houses. But Australia is such a big place—it’s very difficult to quantify these impacts on a continental scale,” Professor Ulm adds. “These smaller islands provide a way for us to understand how people transform environments.”

In September 2018, more than 20 scientists visited the islands, during a month-long field trip. The CABAH research team included experts in pollen, ancient DNA, charcoal analysis, ground penetrating radar, radiocarbon dating and ceramic conservation.

Postdoctoral researcher Dr Ariana Lambrides, from James Cook University’s CABAH node, specialises in archaeological fish bone analysis. “The work that we are doing on Lizard Island is going to give us a high-level record of the ways that people were interacting with the marine fishery here for thousands of years,” she explains. “And that’s really important, because it’s going to give us a unique record of off-shore island exploitation along the Great Barrier Reef.”

Professor Simon Haberle, from the CABAH Australian National University Node, extracts pollen and charcoal evidence from sediment cores to help reconstruct past landscapes. His research will help to build a picture of how fire was used to manage the island landscape over thousands of years.

“A lot of our work now is with communities, finding out what they want from the research we do. The use of fire is a key kind of information that local communities are very interested in—and could also be very useful for managing those environments in the future,” he says.

This close collaboration with the Dingaal People, means that the quantitative data being collected in the field can be pieced together with qualitative data—stories from the community.

“We are using skills, methods and techniques to elaborate our understanding in a way that is meaningful to Indigenous communities, but also speaks more broadly to the general public,” Professor McNiven adds.

CABAH researchers involved in the 2018 Lizard Island project include: Chief Investigators Simon Haberle and Laura Weyrich, postdoctoral researchers Ariana Lambrides and Feli Hopf, Associate Investigators Christian Reepmeyer, Andrew Fairbairn, Fiona Petchey, Kelsey Lowe, Holly Jones-Amin, Martin Potter and Billy Griffiths, Partner Investigator Brit Asmussen, and PhD candidates Nathan Woolford and Lauren Linnenlucke.

CABAH researchers using 3D laser scanning technology to examine a shell midden on Lizard island. Credit: CABAH.