Awoonga still pulling the strings for barramundi
LAKE Awoonga continues to provide an accurate barometer of Gladstone barramundi stocks, according to Infofish Australia's mid-season barra review.
The report showed a mixture of positive and negative data.
Stock levels have declined due to poor natural recruitment from 2016-18, coupled with no top-up of stocks from Awoonga as the dam is yet to spill in 2018.
The overall catch rate is lower than the 2018 forecast, with the fish per fisher day rate dropping to 1.7, compared to a forecast of 2.2.
On the flip side, the average size of barra was 773mm and will remain high, while the percentage of legal fish also remains high at 71.4 per cent.
Infofish Australia's Bill Sawynok wasn't surprised by the decline in stock levels given Awoonga was yet to spill this year.
"At the start of the year it was near 100 per cent, meaning it was likely to spill and release more fish into the Boyne River,” he said.
"That would've maintained our catch rates - our estimates were based on some spilling. We've had to revise down our catch rates but they're still in pretty good shape.
"The figures there are better than most other areas for barramundi; they're better than the Fitzroy (River) in terms of the overall catch rate.
"The catch rate for legal size fish is just marginally better than the Fitzroy, but they're pretty comparable.”
While the Fitzroy River is entirely net-free and the Boyne isn't, the latter had its numbers boosted by spills in March and October last year.
"That obviously added to the stocks in the Boyne River. If you took the Boyne River out and just looked at the Calliope River and the (Gladstone) harbour, the catch rates would be significantly lower than the Fitzroy,” Mr Sawynok said.
"Without Awoonga, the barra fishing in Gladstone would be lower than it currently is.”
Data was also provided on 2017 commercial catches, with 28.44 tonnes caught at a catch rate of 66.6kg per day.
Figures for 2018 are incomplete at this stage, with data only available for a short window between February and March with 48.3kg/day.
Commercial netting on the Boyne recommenced on May 1.