The endangered Macquarie perch has been given protected status in Victoria, meaning recreational fishers can no longer take the native species from the state's waterways.
There was previously a one per bag limit in Lake Dartmouth in the state's north, where there is an active breeding population, and a two per bag limit in the Upper Coliban Reservoir.
But Victorians are now prohibited from taking the fish, commonly known as Maccas, in an effort to give wild populations the best chance to be re-established.
"We're serious about bringing Maccas back," Victorian Fisheries Authority chief executive Travis Dowling said.
"This will ensure the population at Lake Dartmouth can flourish in years to come."
The authority last year began a three-year project to learn how to reliably breed the Macquarie perch in captivity, through examining nutrition, hormones and timing of breeding.
The program is being supported by the federal and state governments, as well as university and community organisations.
The Macquarie perch is found Victorian catchments as well as parts of the Australian Capital Territory and NSW.