Hundreds of thousands of snapper fingerlings will be released off South Australia’s coastline over the coming months, as part of a desperate attempt to replenish critically low stocks of the native fish.
- Snapper stocks in SA’s gulf waters are critically low
- A statewide ban on snapper fishing was introduced last year
- Authorities have spawned 300,000 fingerlings to be released back into the gulfs
A “drastic” total fishing ban was introduced in September 2019, applying to all coastal areas except the state’s south-east, in an attempt to safeguard snapper from overfishing.
An SA Research and Development Institute (SARDI) restocking program was launched around the same time the ban was introduced, resulting in 300,000 fish being spawned.
SARDI’s research director of aquatic sciences, Dr Mike Steer, said the introduction of the fingerlings into SA waters would give the species a chance of recovery.
“This initiative is trying to circuit-break [low numbers] by introducing a number of small fish to give the stock a kickstart in recovery,” Dr Steer said.
Adult snapper stock from both Gulf St Vincent and Spencer Gulf were collected last year to be bred at SARDI’s fisheries facility at West Beach, in Adelaide.
SARDI scientists said they “cracked the code” for successful snapper spawning in October last year, resulting in 300,000 fingerlings.
“We’ve nursed them through their early vulnerable stages … we’ve provided adequate food, we’ve maintained the environment, the water quality has been really good,” Dr Steer said.
Now that they have reached a “healthy” length of 40 to 60 millimetres, they are ready for release.
About 150,000 of the fingerlings will be released from Gulf St Vincent next week, with the remainder to be released into Spencer Gulf during autumn.
“They aggregate in muddy, sea-weedy nursery grounds, so we’ve identified similar nursery grounds in Gulf St Vincent off Ardrossan for the release,” Dr Steer said.
Recovery not guaranteed
Primary Industries Minister David Basham said that, so far, the fishing ban had not produced any promising signs of the species replenishing itself naturally.
Mr Basham said it was extremely difficult to know how much recovery would occur naturally, or what the impact of the introduced fingerlings would be.
“We know it will take these fingerlings three to five years to be catchable size — so these aren’t an instant fix.”
The ban is being reassessed each year, and could be lifted in early 2023 if stocks increase by then, but there are no guarantees.
“We’ll have to wait and see how the science assesses this,” Mr Basham said.