Oral Presentation Australian Society for Fish Biology & Australian Freshwater Sciences Society Conference 2026

Walking together for catfish in the lower River Murray: Western science and First Nations knowledge inform population status and research and monitoring priorities for Tandanus tandanus (145818)

Qifeng Ye 1 , George Giatas 1 , Chris Bice 1 , Courtney Wallace 1 , Ivania Silva 1 , David Short 1 , Josh Fredberg 1 , Sam Hardy 2 , Sheryl Giles 3 , Tracey Steggles 4
  1. South Australian Research and Development Institute, West Beach, SA, Australia
  2. South Australian Murraylands and Riverland Landscape Board, Murray Bridge, South Australia, Australia
  3. River Murray and Mallee Aboriginal Corporation, Loxton, South Australia, Australia
  4. South Australian Department for Environment and Water, Adelaide, South Australia, Australia

Freshwater catfish (Tandanus tandanus) is a culturally significant native species and once contributed to commercial and recreational fisheries throughout the Murray-Darling Basin (MDB). Widespread population declines occurred from the 1970’s associated with altered flow regimes, habitat degradation, barriers to movement, invasive species and over-harvesting. In the lower River Murray in South Australia (SA), despite recognition of conservation concern and protection from harvest  since 1997, substantial knowledge gaps remain regarding the species status and ecology.

To inform future research, monitoring and recovery of freshwater catfish in the lower Murray, we have initiated a study to synthesise long-term (2005–2025) fish monitoring data and First Nations and recreational angler knowledge on population status. Data from numerous fish surveys across the diverse habitats of the SA MDB were examined to evaluate long-term patterns in distribution, abundance and recruitment. Additionally, First Nations groups and recreational fishers shared historical and contemporary knowledge and perspectives on catfish catch locations, abundance, sizes and seasonal patterns.

Over the past two decades, scientific monitoring, traditional and recreational catches suggest freshwater catfish remain uncommon in the lower River Murray. Temporary increases in abundance occurred during and shortly after major flow events in 2010/11, 2016/17 and 2022/23. These increases in catch rates were also notable among recreational fishers but were not sustained long-term. Monitoring also detected low abundances of larvae from 2005–2025 indicating annual spawning.

Freshwater catfish populations in SA appear stable but well below historical levels. Standard fish census monitoring methods (e.g. electrofishing), while useful for rapid assessment, may not be adequate to assess population status in the lower River Murray. Integrating long-term monitoring, cultural knowledge and community observations will help identify priority habitats, and inform future monitoring and research to support environmental flow and habitat management aiming to restore resilient freshwater catfish populations in the lower River Murray.