Standard Talk (15 mins) Australian Society for Fish Biology Conference 2022

Fish Passage in streams of the Gulf of Carpentaria, unique life histories driven by highly variable flow regimes (#23)

Tim Marsden 1 , Melinda Scanlon 1
  1. AFPS, Fern Bay, NSW, Australia

Throughout streams of the Gulf of Carpentaria (GOC) the passage of migratory fish is critical to the ongoing maintenance of fish populations. The highly irregular nature of flows within these systems creates a diverse range of permanent and intermittent fish habitats. Fish populations need free movement within and between these habitats, with adults needing to reach suitable spawning habitats, often in the sea, and juveniles needing to disperse into nursery habitats to grow or to recolonise previously dry habitats. The construction of several fishways on tidal barriers and fish community sampling within streams of the GOC has provided an opportunity to examine the migratory behaviour of many species that have previously been poorly studied. Results from fishway sampling has demonstrated that a wide range of species previously thought to be non-migratory are undertaking migrations within these systems, often as both juveniles and adults. While fish community sampling has pinpointed specific life histories adapted to the wet/dry conditions within the catchment. These results link the diverse flow regimes of these intermittent streams to the migration requirements of the local fish communities and highlights the highly important role fish passage maintenance/remediation at barriers plays to maintaining fish communities in these systems.