Bass stocking modelling: Optimised stocking of Australian bass, by testing modelled estimates of predator impact
Freshwater Trust Allocation
2008/09 - $52,251
Aim
To develop a predatory impact model to optimise stocking rates of Australian bass in freshwater impoundments
Background
Australian bass is a predatory species commonly stocked in NSW freshwater impoundments. Bass feed mainly on macroinvertebrates, aquatic and terrestrial insects and forage fish. The project is using 5 south coast impoundments to quantitatively test Predatory Impact Model simulations in freshwater environments.
Relevant data on stock dispersal & habitat and seasonal production requirements of bass will be collected through sampling techniques at freshwater impoundments. Simulations will be run to estimate stocking density in each of the target impoundments. Bass will then be stocked at modelled and non-modelled densities to determine if stocking at modelled densities better achieves desired production levels than non-modelled densities. Fish will be marked to allow distinction between different cohorts of fish.
Feasibility is being assessed by monitoring dispersal from the release area, and the through bi monthly sampling to monitor growth and survival of stocked bas and then growth and survival of stocked fish over the initial two years of life will be compared to stocking at non-optimised densities.
The relative survival of stocked fish is being evaluated in terms of other factors including temperature, impoundment levels and rainfall to determine the effects of these parameters on survival of fish stocked during the life of the project. This will give a definitive indication of whether stocking fish at densities estimated by the freshwater predatory impact model lead to a better survival and growth of stocked fish.
