Prospects for the distressed Australian bass population in the Snowy River have taken a turn for the better following the continuation of a restocking program, which shows more fish are slowly returning to the popular river.
A restocking program funded by the Southern Rivers Catchment Management Authority (SRCMA) has resulted in the release of more than 200,000 hatchery-reared Australian bass fry into the upper reaches of the Snowy River.
With funding from Industry & Investment NSW (I&I NSW), NSW Recreational Fishing Freshwater Trust Expenditure Committee and SRCMA , researchers from I&I NSW and Southern Cross University have been studying the success of these stockings.
Research includes monitoring the growth, survival, diet, habitat selection and dispersal rates of stocked Australian bass in the Snowy River.
Southern Cross University researcher, Leo Cameron, based at I&I NSW’s Grafton Aquaculture Centre, said Australian bass were once abundant in the Snowy River, but numbers had dropped significantly during the past 20 years.
“Hundreds of thousands of the fish, measuring between 15 and 25 millimetres were released into the Snowy River between 2007 and 2009 and preliminary results have determined that Australian bass are slowly returning to the river,” he said.
Mr Cameron said the stocked Australian bass had been re-captured using electrofishing and trapping.
“Stocked Australian bass reached 120 millimetres within six months after being stocked and were regularly collected from deep holes containing boulders and in low flow sections of the river,” he said.
“Currently we are finalising a major component of the project, which will use otolith (ear bone) microchemistry analysis to determine the source of juvenile Australian bass collected during this project.
“This information will confirm if all Australian bass collected were hatchery-reared individuals (stocked) or if some were natural recruits.”
Mr Cameron said researchers were also determining the environmental tolerances of juvenile Australian bass, to assess the suitability of future stockings of this species under extreme climatic conditions, such as those seen during the winter months on the Snowy River.
“Improved understanding of the behaviour, survival and growth of stocked fish and their impacts on the systems into which they are stocked will help inform future stocking programs. This will lead to more successful stocking programs in the future,” he said.
Editor's Note: Original news release can be found here.