GLADSTONE BARRAMUNDI FORECAST SEASON 2018

There are a total of 11 forecasts made for Barramundi in size of fish, catch rates, trends in stocks, recruitment and commercial catch. Catch details are based on the top 20% of fishers (T20) that catch 80% of the fish. Their catch rates do not reflect the catch rates of the total fishing population however 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 2018 forecasts

Overall outlook

Stock level to remain steady with the additional fish that spilled from Lake Awoonga in 2017 with the catch rates to also remain steady at 2.0-2.4 fish/fisher/day but elevated in the Boyne River, however natural recruitment is likely to be poor.

T20 Fishers

  • There will be a reduction in the percentage of legal fish in the catch due to the size range of fish spilling from Awoonga in 2017 being predominantly 500-700mm
  • Overall catch rate and catch rate for legal fish will remain steady but may increase if fish spill from Lake Awoonga again as is possible in early 2018 (Feb-Apr)
  • Catch rates in the Boyne River likely to be higher than for remainder of Gladstone Harbour due to fish spilling from Lake Awoonga in 2017 with little evidence of these fish moving beyond the Boyne River
  • Stock level to remain steady with natural and fishing mortality likely to be offset by additional fish spilling from Awoonga

Commercial Fishers

  • Commercial Barramundi catch data for 2017 is only available for Feb-Sep and that indicates catch and catch rates are within the forecast range
  • Commercial catch and effort data will be updated when complete 2017 data are available

Environmental conditions

  • Neutral to slightly La Niña conditions are forecast for the recruitment period (Jan-Apr) with an average wet season with neutral conditions for the remainder of the year
  • Forecast for Gladstone catchments is a 50-60% chance of exceeding median rainfall from Feb-Apr and rainfall to date suggests that conditions may not be conducive to good recruitment (expected)

Infofish Australia
January 2018

MEASURE FORECAST

ACTUAL

GRAPH

GLADSTONE 2018

2018

T20 Fishers
Trophy fish >1m
Legal - trophy fish 580-999mm
Undersize fish 200-579mm


10% (0-20%)
55% (45-65%)
35% (25-45%)

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T20 fishers
Actual catch rates
Fish/tagger/day

Overall
2.2 (2.0-2.4)
Legal fish
1.8 (1.6-2.0)

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T20 fishers
Actual catch rates
2009-2018
Fish/tagger/day
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T20 fishers
Catch rates percentage change 2018-2017
Overall
+5% (-15%-+25%)
Legal fish
+5% (-15%-+25%)
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Barramundi tags in Gladstone indicator of trends in stock
Model tagged fish
most likely and range
Tagged fish 2018 (Jan-Dec)
500 (400-600)

+20% (0-+40%)
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Recruitment
Recruits/fisher/day
Poor
<0.1 (0-0.1)
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Awoonga dam levels High probability that the dam will spill again in 2018 Dam spilled
Jan-Mar 2015
Did not spill 2016
Spilled
Apr 2017
Oct 2017
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Climate outlook BOM NINO34
Weak La Niña
Jan - Apr 2018
Neutral
May-Oct 2018
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Rainfall Outlook Nov-Jan BOM forecast
50-60% chance of exceeding median rainfall for Gladstone catchments
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DATA SOURCES

Data used in the Fitzroy Barramundi Crystal Bowl are:

  • Sponsored By

    GLADSTONE
  • Supported By

    CAIRNS, GLADSTONE
  • Supported By

    GLADSTONE