Sound waves help bring back the black bream:
29/04/09:– About 30 black bream are being implanted with acoustic tags (pingers) to monitor their movements and improve fish migration along the Murray River.
The breams’ movements are being monitored by NSW Department of Primary Industries (DPI) Aquatic Ecosystems Researchers in collaboration with scientists from South Australia and Victoria.
The work is being funded by the Murray-Darling Basin Authority (MDBA) and is part of the ‘Sea to Hume Dam’ project.
As part of the project, the MDBA has built fishways at the Murray River Barrages to allow movement of estuarine and freshwater fish between the Coorong and Murray River.
NSW DPI research scientist based at Narrandera Fisheries Centre, Dr Lee Baumgartner, said black bream were an important commercial and recreational species in the Coorong, but scientists have rarely detected them migrating through the newly-constructed fishways.
“This larger study aims to gather information on their migration cues and patterns within the Coorong region,” he said.
The researchers will install 13 ‘listening’ stations between Goolwa Barrage and Tauwitchere Barrage to monitor the acoustic tags in the black bream.
“The tags emit sound waves on a unique frequency, which enables the identification of individual fish. Whenever a tagged fish enters the vicinity of a listening station, its number, location, date and time will be recorded. Scientists can then use this information to plot the movements of fish through time,” Dr Baumgartner said
He said system would provide details on where and when each fish moves during a period of about 18 months (the battery life of the tags).
“As well as providing an insight into black bream movements, the research will provide information on important habitats within the Coorong, and how fish may respond to environmental change such as modifications to flow regimes.
“Ultimately, this information will assist in the conservation and restoration of fish populations in the Coorong and Murray River,” Dr Baumgartner said.
Researchers are calling for help from anglers fishing in the Lower-Lakes and Coorong region of the Murray River to help monitor large-distance movements of black bream.
If you reel in a black bream bearing a numbered green tag in the next 18 months, please note the tag number, length of fish, location and date it was caught. Then throw it straight back into the water alive, and call 1800 119 194. When you call the team with your information you can claim a reward.