Murray cod (Maccullochella peelii) is a large (length >1.4 m) and long-lived (to 48 years) freshwater apex predator, endemic to Australia’s Murray-Darling Basin (MDB). Its prominence in the Basin is reflected in its cultural significance to both indigenous and non-indigenous Australians. The Lower River Murray, spanning ~800 km at the terminus of the MDB, is heavily impacted by anthropogenic modification of flows and connectivity. Murray cod was historically abundant in the region, but populations have substantially declined due to altered flow and habitats, barriers to movement and over-harvesting. These threats, coupled with the emerging impacts of climate change, continue to compromise population resilience. Increasingly, however, rehabilitating Murray cod populations is an objective of water management and habitat restoration.
Here, we present 20 years of data on Murray cod demographics in the Lower River Murray and explore factors influencing population dynamics, including early life-history, growth and recruitment, movement and genetics. We discuss the benefits and risks of contemporary water and fisheries management practices, and identify future conservation opportunities. Successful Murray cod conservation requires a mechanistic understanding of life history, habitat requirements and population dynamics, alongside robust population monitoring.