Walking together on Country: combining Indigenous knowledge and western science to understand freshwater resources in a hypersaline environment

The incorporation of “soft data” from local community experts has long been recognised as a valuable source of information in scientific studies. However, in practice many quantitative scientists find it challenging to incorporate the resulting qualitative data into their studies. However, we present an example from South Australia, where the combination of Indigenous knowledge and historical maps was a key component. The study has aimed to locate freshwater resources along a long (180 km), thin (less than 2 km wide) barrier peninsula, determine their hydrological characteristics, and understand their resilience to climate change impacts. The peninsula contains a wealth of culturally important sites, including “soaks”, which are small, persistent wetlands that constitute the only source of fresh water in an environment with seawater on one side and a hypersaline, RAMSAR-listed estuarine lagoon on the other. These soaks also support the native wildlife that inhabits the regions. Thus, the project included considerable consultation and collaborative fieldwork with the Ngarrindjeri community to locate and sample soak hydrology. Dozens of soaks were identified through a combined approach of remote sensing and community knowledge, and have subsequently been sampled for salinity and stable isotopes to determine water sources. The results of the project are expected to underpin resource management of the region by both state government and Indigenous rangers.