GLADSTONE BARRAMUNDI REVIEW 2016

There were a total of 11 forecasts made for Barramundi in size of fish, catch rates, trends in stocks, recruitment and commercial catch. Taggers catch rates do not reflect the catch rates of the total fishing population however as taggers are generally in the top 20% of fishers that catch most fish their catches are more sensitive to changes in fish stocks and are comparable from year to year. Forecasts are available at www.crystal-bowl.com.au.

Season 2016 forecasts versus actual

Taggers

  • Of the 9 forecasts for taggers 6 (67%) were within the forecast range while 2 were within 10% of the forecast range and 1 was within 15% of the forecast range
  • Catch rates were down a little compared with 2015 and the downward trend continues since 2012 when they were heavily influenced by fish spilling from Awoonga
  • Forecast of poor recruitment was accurate and reflected the El Niño conditions that existed over the recruitment period (Jan-Apr) – rainfall in Feb was too late to have a significant influence on recruitment
  • The trend in stock levels is downward with little recruitment to offset fishing and natural mortality and this is reflected in a fall in the number of tags
  • The numbers of trophy fish in the Calliope River, Boyne River and Gladstone Harbour are well down on previous years as the fish that spilled from Awoonga from 2011-2014 have largely gone

Commercial Fishers

  • For the commercial catch the data are only available for Feb-Aug (will be updated when full season catch is available)
  • The catch is likely to be in the forecast range however the catch rate will be lower than forecast
  • Commercial effort is already the second highest in the last 10 years even though there are still 2 months of data to be included
  • The increase in commercial effort is likely to reflect some of the effort displaced from the Fitzroy/Keppel Bay Net Free Zone

Environmental conditions

  • El Niño conditions persisted through to May and were neutral through to Oct
  • There were minor flows in the Calliope River in Feb and Jul however there was no flow in the Boyne River as Awoonga did not spill

Infofish Australia
January 2017

MEASURE FORECAST

ACTUAL

GRAPH

GLADSTONE 2016

2016

Fish sizes
Undersize fish 200-579mm
Legal - trophy fish 580-999mm
Trophy fish >1m


30% (20-40%)
60% (50-70%)
10% (20-40%)

Taggers/Bounty
25.9%
70.1%
4%

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Percentage of fish in size ranges

Highest  Lowest
LEGAL-TROPHY
2007    2009
78.8    18.3

TROPHY
2012    2007
29.7    3.0

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Actual catch rates taggers and Bounty

Fish/tagger/day

Taggers

Overall
1.6 (1.3-1.9)
Legal fish
1.1 (0.9-1.3)

Taggers

Overall
1.3
Legal fish
1.0

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Catch rates percentage change compared with 2015

Taggers/Bounty

Overall
+10% (0-20%)
Legal fish
0% (-10-+10%)

Taggers

Overall
-12.7%
Legal fish
-19.0%

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Barramundi tags in Gladstone indicator of trends in stockMost likely and range  Tagged fish 2016 (Jan-Dec)
100-300
-35--65% compared with 2015
Tagged fish 2016 (Jan-Dec)
182
-% compared with 2015
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RecruitmentRecruits/fisher/day Poor Poor

0.01

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Gladstone Harbour and Barramundi
Low Numbers of Trophy Fish
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Calliope River flow and Barramundi
Low Numbers of Trophy Fish
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Boyne River flow and Barramundi (Flow data only to 2012)
Low Numbers of Trophy Fish
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Awoonga Dam Levels Not forecast to spill Did not spill in 2016
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Commercial catch
Grids S29/S30/S31
Catch (tonnes)
Catch rate (kg/day)
Catch
30 (27-33)
Catch rate
100 (90-110)
Catch
23.92
(Feb-Aug)
Catch rate
51.89
(Feb-Aug)
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Commercial effort
Grids S29/S30/S31
Days fished
No forecast Days
461
(Feb-Aug)
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DATA SOURCES

Data used in the Fitzroy Barramundi Crystal Bowl are: