Boffins provide evidence for mulloway debate

WITH a promised consultation process on the bag and size limit of mulloway in NSW, the NSW Recreational Fishing Alliance says anglers need to be asking more questions of researchers and scientists about what we should be doing to make better informed decisions about the mulloway's future in NSW.

The latest NSW RFA newsletter highlights some interesting facts from experienced scientists and researchers on the subject of mulloway aka jewfish in NSW.

We thought we'd share with readers some of the interesting feedback garnered from these boffins on the subjects of commercial fishing for immature jewies and raising size limits:

  • Essentially, a modest harvest of immature fish does not impact the fishery as much as removing a "big mumma" and the consensus is we need to increase the size limit of mulloway to at least a size of first maturity and the main issue is to preserve the really big trophy fish (greater than 1 metre) as these are the highly fecund individuals with the largest eggs, the greatest number of eggs and eggs of the highest quality.
  • Older fish produce larvae that are more viable as shown in Norway and in US (e.g. Berkeley et al. 2004 Ecology 85:1258-1264). Those individuals have survived the gauntlet and have the genes that should be passed on. By removing those quality individuals, the bulk of reproduction is maintained by the first-time spawners – effectively "teenagers". For example, a single 61 cm red snapper Lutjanus campechanus) equals the fecundity of over two hundred (221) 43 cm snappers! (Bohnsack, J. Austral. Ecol 23: 298-304)

From the above it's not difficult to conclude that a slot limit for jewfish is a logical and sensible step, for example from 70 cm – 1 metre and we all have to let the rest go - including commercial fishers.

Stay tuned for more on this issue.

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