Background
Australia has one of the highest recreational fishing participation rates in the world. With much of the population concentrated along the coastal fringe, recreational fishing effort is focused in estuarine and nearshore coastal environments. To address recruitment limitation of key recreational species, an aquaculture-based marine stocking program was established in NSW, with fish releases targeted to estuarine habitats.
Methods
Research and monitoring activities guide the stocking program through a combination of pilot-scale releases and evaluations of full-scale stocking programs conducted across multiple estuaries. A multidisciplinary approach incorporating acoustic telemetry, tag-recapture, citizen science and genetic parentage analysis has been used to assess the effectiveness of stocking strategies and identify factors influencing success.
Results
Mulloway and dusky flathead have been stocked annually in NSW estuaries since 2021. Genetic parentage analysis indicated limited recruitment of fingerling releases to the fishery to date, whereas tag-recapture studies demonstrated substantially improved outcomes from releases of larger fish. A novel acoustic telemetry study generated size-based mortality estimates that supported patterns observed from both genetic and tag-recapture data.
Conclusions
Although marine fish stocking in NSW remains a relatively new initiative and measurable fishery-level benefits may take several years to emerge, the monitoring program has already informed management decisions regarding optimal release size, stocking rates and the identification of key nursery habitats.