A marathon scientific research project has successfully rejuvenated stocks of a fishermen’s favourite, the black bream, in the Blackwood River.
Challenger Institute of Technology, working closely with Murdoch University, the Fisheries Research and Development Corporation and the West Australian Fish Foundation, embarked on the mission to restore depleted stocks of the iconic species in 1999. Fifteen years later, evidence has emerged that the signature commercial fish of the Blackwood River, in Western Australia’s south west, is breeding in sufficient numbers for the species to have recovered.
Challenger Institute’s Australian Centre for Applied Aquaculture Research (ACAAR) has been at the forefront of restocking projects that have drawn international acclaim, including western school prawns in Perth rivers and the mulloway along the WA coast.
The success of the black bream project completes an impressive triumvirate of restocking projects of highly regarded local marine stocks.
“This is one of those occasions where a depleted estuarine fish stock has been rehabilitated through restocking,” said ACAAR director Greg Jenkins.
“The science of restocking is getting stronger each year and WA scientists are playing a significant role in that development,” he said.
More than 220,000 black bream cultured at Challenger Institute were released as small juveniles into the Blackwood River Estuary in 2002 and 2003 and subsequently grew to the legal length for capture (250 mm).
Within five years the numbers of legal sized black bream in the river had quadrupled. Stocks reached the stage where the Blackwood commercial fisherman resumed operations in the Blackwood River by 2006 and recreational fishermen are now enjoying significant catches without threatening the viability of the species.
Murdoch University continues to monitor the health of river’s black bream population with the support of the Recreational Fishing Initiatives Fund, Recfishwest and the WA Department of Fisheries. “There is evidence that the cultured fish reached maturity and produced progeny that now contribute to the fishery,” said Murdoch University’s Prof Ian Potter.
“The outcomes of this unique project have greatly exceeded expectations and have proved to be of worldwide interest,” he said.
The Blackwood River is a major river and catchment that winds through Bridgetown, Nannup and into the Southern Ocean near Augusta.
ACAAR is Challenger Institute’s world-class facility for marine finfish research, being well-recognised and respected throughout Australia and the world.
PHOTO CAPTION: ACAAR director Greg Jenkins at Challenger with a live example of the black bream that have repopulated the Blackwood River.