Background
In Tasmania, Banded Morwong are commercially harvested by a small-scale coastal gillnet fishery. Prior to 1990, the species had little commercial value. In the early 1990s a targeted fishery for Banded Morwong started to supply domestic live fish markets. All holders of a Tasmanian Fishing Boat Licence were able to take Banded Morwong and, as a result, there was a dramatic increase in effort directed at the species, with reported catches peaking at 145 t in 1993/94. Catches fell dramatically in the late 1990s, with 34.6 t landed in 1999/2000.
A quota management system with a Total Allowable Catch (TAC) was introduced in late 2008 to regulate fishing mortality at key fishing grounds on the east coast. The TAC has undergone a staged reduction from 38.8 t in 2012/13 to 31 t in 2017/18. The TAC remained at 31 t until the current season, 2021/22, where it was set at 35.8 t. The increase was intended to allow the fishing industry to recover from a 23.9% TAC under-catch in 2020/21 that was due to deflated market conditions during the COVID-19 pandemic. In addition, a temporal closure is in place for 1st March to 30th April each year, encompassing the species’ peak spawning period. The species is subject to keyhole size limits, which are currently set at a minimum legal size of 360 mm and a maximum legal size of 460 mm.
A sampling program commenced in 1995 to obtain biological information, in particular size and age compositions, to better inform Banded Morwong assessments. Truncations in length and age compositions have been observed over the course of this sampling program, particularly for female fish. In recent years, age compositions appear to have stabilised but remain at levels much lower than when surveys began. Old fish (> 20 years) are rarely observed, and relative proportions of fish < 8 years old have increased. Changes in mean length at age of individuals aged between 2–10 years, and fluctuations in length at maturity, have also been observed.
