There are at least four clear needs supporting the proposal, and these are separated below.
1) Genetic health is important for healthy fisheries. A genetically healthy population has good natural recruitment, connectivity to adjacent populations to promote gene flow, sufficient genetic diversity (this relates directly to adaptive potential) and low inbreeding. If genetic health is eroded, populations are less resilient to anthropogenic and natural impacts, affecting their persistence over the long term.
2) Public investment to support healthy fisheries is significant. There is continuing extensive investment in native fish protection and enhancement, including more than $13B to the MDB under the Basin Plan to restore populations and recover ecosystem function. The relative outcomes of these efforts need to be evaluated to ensure the greatest benefits from public investment.
3) Fish stocking is a key component of recovery efforts. Millions of hatchery fish have been stocked throughout Australian waterways in the last two decades. There are limited data on the impacts of stocked fish on the genetic health of wild populations, but our recent FishGen research indicates issues with using closely related and inbred broodfish within hatcheries.
4) The project will help maintain and improve the genetic health of Australia’s fisheries assets. By providing hatcheries with information to maximise the genetic health of stocked fish, the work will minimise negative impacts on wild populations. This includes (i) informing on minimum population size and geographic location for broodfish sampling to capture appropriate wild genetic diversity, and (ii) identifying the best broodfish combinations within and across hatcheries to avoid inbreeding and promote health of stocked fish. This will help to build natural genetic resilience so that populations can adapt to rapidly changing environments under climate change.
The work will promote the long-term sustainability of wild fish populations in freshwater ecosystems by protecting the genetic integrity of wild populations. This will contribute to realised economic benefits for recreational and commercial fishing, tourism, cultural and mental-health in communities in regional Australia.