August 28, 2017
It is widely known that Murray-Darling Basin native fish use river flows as a cue for migration and spawning. Latest research into silver perch (Bidyanus bidyanus) by Victoria’s own Arthur Rylah Institute has uncovered that flows are also critical for larval and juvenile phases.
Researchers aged silver perch using the fish ear bones, also called otoliths, from individuals sampled across the Murray River. The study found that for a fish species that can live to 17 years old, few are present beyond 7 years of age.
Zeb Tonkin, Scientist from Arthur Rylah Institute said, “This research has found that large flood events and environmental flows play a critical role in the life cycle of the fish by aiding dispersal, growth and survival of juvenile fish.”
“Silver perch were once the most widespread native species in the Murray-Darling Basin, but numbers have declined dramatically.”
The outcome of the findings is dispersal of silver perch larvae is now a priority for the Murray-Darling Basin Authority’s (MDBA) environmental watering program.
“Coordinated flow releases have been effective in helping silver perch disperse from the Murray River into the Campaspe and Goulburn systems.”
