A team of Australian researchers have weaved together modern science and Indigenous knowledge to reveal stunning new insights into the evolution, history and future of the southern Great Barrier Reef. The 24-day voyage, led by The University of Queensland, returned to Brisbane today on research vessel (RV) Investigator, operated by CSIRO, Australia’s national science agency.
The research was co-designed with the Darumbal Traditional Owners of Sea Country and their close neighbour the Woppaburra people and has revealed landscapes where First Nations people lived on the southern Great Barrier Reef before the region was submerged when sea levels rose to present levels around 7000 years ago.
Voyage Chief Scientist Professor Helen Bostock from The University of Queensland said the research team have produced intricate maps of the seafloor and sub-seafloor using RV Investigator’s advanced sonar systems, revealing stunning images of the ancient landscapes.
“First Nations people arrived in Australia over 65,000 years ago when sea levels were 80 metres below present day,” Professor Bostock said.
“At that time, the Great Barrier Reef area was a vast coastal plain bordered by towering forests that stretched inland. Our research has revealed submerged rivers, lakes, estuaries and beaches in stunning detail and helps tell the story of the First Nations people who lived on this land in times past.”
The voyage team included Land and Sea Country Rangers from the Darumbal and Woppaburra Traditional Owner groups. They worked with other researchers to connect scientific findings with their cultural knowledge and songlines, the pathways of knowledge that cross the landscape linking important sites and stories for First Nations people.
Land and Sea Country Ranger Nataliah Backo from the Darumbal people said the research gives them a deeper connection to their history, ancestors and the stories held beneath the ocean.
“We hope this journey makes our families, ancestors and the Darumbal people proud, while creating stronger pathways for our younger generations to continue caring for and protecting our Land and Sea Country,” Ms Backo said.
Echoing these words, Land and Sea Country Ranger Tshinta Barney from the Woppaburra people emphasised the importance of the shared experience and weaving together Indigenous knowledge and modern science.
“Being surrounded by such beautiful people, sharing knowledge and learning from one another has made this experience a very special and memorable one for me,” Ms Barney said.
“I feel truly blessed to have had the opportunity to learn about the different aspects involved in mapping and understanding the evolution of Sea Country.”
To reconstruct past conditions, the research team collected more than 20 sediment cores from the seabed to investigate the submerged landscapes. These cores will be examined for the types of sediments and fossils they contain. This analysis allows researchers to reconstruct the historical climate, sea level rise, vegetation and evolution of the southern Great Barrier Reef in a process called paleo environmental reconstruction.
“Seafloor sediments act like time capsules and allow us to reconstruct the history of the region, from its past as a wide coastal plain to the development of the modern Great Barrier Reef, and connect this with the cultural stories of the Darumbal people and their close neighbours the Woppaburra people,” Professor Bostock explained.
Ocean dynamics were also examined during the voyage, including investigating how the powerful East Australian Current (EAC) interacts with the reef.
CSIRO Voyage Manager Matt Kimber said RV Investigator provided researchers with an impressive range of scientific capability to study the structure, dynamics and productivity of the southern Great Barrier Reef, a region that remains poorly understood.
“RV Investigator is an absolute workhorse for ocean science, and we’ve put the vessel’s advanced oceanographic systems and scientific equipment to great use in gathering a broad range of data to increase our understanding of ocean dynamics in the region,” Mr Kimber said.
“These data will reveal how the EAC interacts with the seafloor of the southern Great Barrier Reef, helping us better understand the movement of currents and how life is sustained on the reef.”
The oceanographic data will also contribute to the CSIRO eReefs model, which is used to understand past and present ocean conditions and predict how future changes might impact the reef. Importantly, eReefs modelling will help researchers identify potential ‘refugia’ for reef species, areas where they might be shielded from the impacts of increasing heat driven by climate change.
Professor Bostock said the collaborative voyage had been highly successful and would produce knowledge to enhance understanding of the natural seascape and cultural heritage values of the Great Barrier Reef Marine Park.
“This research will fill important knowledge gaps identified in the Great Barrier Reef Marine Park Authority 2024 Outlook Report and contribute to the Reef 2050 Plan,” Professor Bostock said.
Analysis of the data and samples collected during the voyage will continue over coming months and the knowledge generated will be shared with Traditional Owners and marine park managers.
“By weaving together modern science and traditional knowledge systems, we have a much greater understanding of the story of the southern Great Barrier Reef, which will help us better protect its incredible natural and cultural values into the future.”
CSIRO acknowledges the Traditional Owners of the land, sea and waters, of the area that we live and work on across Australia. We acknowledge their continuing connection to their culture and pay our respects to their Elders past and present.
This research is supported by a grant of sea time on RV Investigator from the CSIRO Marine National Facility.
