A shell midden, or a shell mound, is a central place where people would leave their food rubbish – such as fish shells or fish bones. If a particular shell midden was used for a long time, it could sometimes become quite big and easy to spot, such as the unusual shell midden that Sean Ulm and Ian McNiven’s team found on Lizard Island.
Ariana says that most middens in the Lizard Island region were quite different from this exceptional find, because they generally don’t contain so many fish bones. “This provided me with an excellent opportunity, and I joined the team as a postdoctoral researcher at JCU Cairns as part of the Australian Research Council’s Centre of Excellence for Australian Biodiversity and Heritage (CABAH) in 2018.”
A reference collection of fish bones
In the past couple of years Ariana has worked to build a new reference collection of fish bones from the Great Barrier Reef. “With no reference material, it's hard to classify what we find,” Ariana says. “I am putting a lot of work into this, and it's developing nicely now.”
Ariana expects that the growing collection will help her to speed up her work. “Imagine, you have all of these tiny, fragmented fish bones from an archaeological site, but you need to determine the species of fish they are from. This is much easier to do if we have access to modern reference material,” she says.
However, the sheer number of fish species (biodiversity) found in the waters of the Great Barrier Reef is very high. This can make identifying these fragmented fish bones difficult, even if you have a comprehensive reference collection already. “The features on the bones are sometimes not distinct enough to allow you to identify the particular species,” Ariana says.
High-tech fish bone analysis
“This is why we use two complementary methods. First, I analyse the bones based on their morphological features. Then some of these bones are sent to Dr Michael Buckley’s lab at the University of Manchester to verify the identifications that I have made. In the lab, they use an approach called 'ZooMS' (Zooarchaeology by Mass Spectrometry) where they use collagen fingerprinting to conduct species identifications of archaeological bone.”
By using collagen fingerprinting, scientists are able to establish more precise identifications. “It gives us a more specific understanding of where people were going in the environment to fish and, the particular fish species people were choosing to eat. It also helps us to better understand the fishing technologies that may have been used,” Ariana explains.
Small reef fish for dinner
On Lizard Island (Jiigurru), people were preparing and eating fish at what the Dingaal and Ngurrumungu Traditional Owners today describe as their campsites. “They weren’t looking for the big catch,” Ariana says. “In the past, people were targeting smaller reef fish, like parrotfish, wrasse and small reef sharks.”
These species are generally found within the Lizard Island lagoon, quite close to land. “We don't see a lot of evidence that large fish were caught. So, perhaps people weren’t necessarily going further offshore to catch fish, but instead there may have been a preference to net or spear fish close to shore.”
Talking history with the Traditional Owners
One of the best things about her job, says Ariana, is working in partnership with Aboriginal and Torres Strait Islander communities. “For the communities that I have the privilege to work with there is a real love and connection to the ocean and fishing. As soon as you mention fishing, everyone's eyes light up,” Ariana says. “There is real excitement around conversations about fishing. There is a shared interest in learning more about what range of species and habitats were used by the Old People and how this compares to what communities are doing today.”
Ariana thinks that researchers get more meaningful results if they work together with Traditional Owner communities. “We have an expertise, which is looking at the archaeology in terms of the scientific techniques that we can implement – such as excavating and analysing the recovered finds,” Ariana says. “But in terms of interpretation, it's about coming together and discussing our finds with communities in partnership.”