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Mulloway is a widely distributed species in Australian waters. Stock status is sustainable in WA and SA, depleted in NSW and undefined in QLD.

Mulloway has a wide distribution in Australia, from the Gascoyne region on the west coast of Western Australia, around the southern coasts of the continent, and up to the Wide Bay–Burnett region on the east coast of Queensland [Kailola et al. 1993]. 

Biological stock structure for Mulloway in Australia is uncertain. It has been suggested that a single panmictic population occurs in Australia [Archangi 2008]. However, regional differences in genetics, and otolith morphology and chemistry suggest sub-structuring between populations in New South Wales, South Australia and Western Australia [Barnes et al. 2015, Ferguson et al. 2011].

Here, assessment of stock status for Mulloway is presented at the jurisdictional level—Western Australia, Queensland, New South Wales and South Australia.

Western Australia

The majority of Mulloway catches in WA are landed by commercial fishers, making up approximately 70-80 per cent of the total catch over the last ten years [Gaughan and Santoro, 2020]. Annual commercial catches have declined from around 60 t in 2001–02, but have remained relatively steady since 2007–08 at 11–28 t. In 2019, the total State-wide commercial catch was 13 t. The recent lower catch levels are associated with reductions in fishing effort by the main demersal fisheries that catch Mulloway (the West Coast Demersal Scalefish (Interim) Managed Fishery (WCDSIMF) and Gascoyne Demersal Scalefish Managed Fishery (GDSMF) [Gaughan and Santoro, 2020]. Boat-based recreational and charter catches of Mulloway remain low, i.e. < 10 t per year, with most landed in the Gascoyne and West Coast Bioregions [Gaughan and Santoro, 2020; Ryan et al. 2019]. Shore-based recreational catches of Mulloway are unknown.

At the Western Australia stock level, catch per unit effort (CPUE) of Mulloway derived from line fishing methods has remained low since 2008 (after management changes to the WCDSIMF and GDSF) at approximately 2–6 kg per block day (reporting blocks are 60nm×60nm) [DPIRD, unpublished data]. This reflects the low level of commercial targeting of this species. CPUE of those two main fisheries that land Mulloway has been highly variable in the last 10 years. Although CPUE has increased slightly in recent years, this was mostly in the West Coast Bioregion and is not reflected in substantial increases in catch or from changes in targeting [DPIRD, unpublished data]. 

A data-limited Catch-MSY model of the Western Australian stock of Mulloway produced an MSY of 36 t (95 per cent CLs: 25–49 t) and annual catches have fluctuated within or below this band since 1975–76, except for between 1999 and 2002 [DPIRD, unpublished data]. Estimated fishing mortality experienced by the stock in 2018 was 0.05 year^-1 (95 per cent CLs: 0.03 to 0.12 year^-1). As the upper 95 per cent CL of this performance indicator is below the estimated level of F_MSY (0.15 year^-1), the stock is unlikely to deplete to a level at which recruitment could be impaired if the current level of catch is maintained. The point estimate for relative stock biomass in 2018 (the depletion level) was 0.66 of the estimated unfished level (95 per cent CLs = 0.38–0.79) [DPIRD, unpublished data]. The point estimate of this performance indicator was above the threshold of 0.5 (B_MSY), and the target is considered as any stock biomass level above B_MSY. The above evidence indicates that the biomass of this stock is unlikely to be depleted and that recruitment is unlikely to be impaired. Furthermore, the evidence indicates that the current level of fishing mortality is unlikely to cause the stock to become recruitment impaired. 

On the basis of the evidence provided above, Mulloway in Western Australia is classified as a sustainable stock.

Mulloway biology [Farmer 2008, Ferguson et al. 2013, Silberschneider and Gray 2008]

Western Australia – Recreational (Catch totals) Shore based catches are unknown, thus landings are likely to be underestimated.

Western Australia – Indigenous (Management methods) Subject to the defence that applies under Section 211 of the Native Title Act 1993 (Cth), and the exemption from a requirement to hold a recreational fishing licence, the non-commercial take by Indigenous fishers is covered by the same arrangements as that for recreational fishing.

Queensland – Indigenous (management methods) for more information see https://www.daf.qld.gov.au/business-priorities/fisheries/traditional-fishing

New South Wales – Commercial (Management methods) Fishers using haul nets in the New South Wales commercial Ocean Hauling Fishery are permitted a bycatch allowance of 500 kg of Mulloway per day.

New South Wales – Recreational (Catch) Murphy et al. [2020] 

New South Wales – Indigenous (management methods)  https://www.dpi.nsw.gov.au/fishing/aboriginal-fishing

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