*

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.

New South Wales

Commercial landings of Mulloway in New South Wales steadily declined from almost 400 t in the mid-1970s to a historic low of 37 t in 2008–09, and have been less than 100 t per year since the mid-1990s [Hughes 2020]. In 2019, the total State-wide commercial catch was 48 t. No trends are evident in commercial CPUE for the two main fishing methods, estuary mesh netting and ocean line fishing since 2009 [Hughes 2020].  The most recent estimate of the recreational harvest of Mulloway in NSW was approximately 12 000 fish weighing an estimated 90 t during 2017–18 [Murphy et al. 2020]; greater than the commercial catch (72 t) in the same period [Hughes 2020]. This estimate only encompassed harvest from NSW households within which a long-term (1-3 year) Recreational Fishing Fee licence holder resided (RFL household). Re-analysis of the previous survey done during 2013–14 [West et al. 2015] for all NSW residents, to allow a comparison with the recent survey, produced an estimate of approximately 19 000 Mulloway harvested by RFL households during 2013–14 [Murphy et al. 2020]. In 2000–01 the National Recreational and Indigenous Fishing Survey [Henry and Lyle 2003] estimated recreational harvest by all fishers in NSW waters at approximately 117 000 fish, noting that this estimate was for a species grouping ‘Mulloway/jewfish’ which encompassed related species, including teraglin (Atractoscion atelodus). While these survey results are not directly comparable due to different sampling frames, the two most recent surveys likely represent a decline in recreational harvest through time. The annual average lengths of Mulloway landed by the commercial fishery have declined since the mid-1990s, but have been stable since the mid-2000s except for the effect of increasing the legal minimum length in 2013 [Silberschneider and Gray 2005, Silberschneider et al. 2009, Hughes 2020]. Up until 2016–17, the New South Wales commercial Mulloway fishery was based largely on juveniles, and the truncated length composition of fish in commercial landings since the early-2000s was indicative of a heavily fished stock (around 80 per cent of catch was less than 700 mm, the approximate length at maturity for female Mulloway in New South Wales) [Silberschneider and Gray 2005, Silberschneider et al. 2009, Hughes 2020]. Only since 2015–16 has the average length of Mulloway in the commercial fishery increased to be greater than 700 mm and only since 2017–18 has the proportion of fish in the landed catch < 700 mm fallen below 10% [Hughes 2020].

Fishing mortality has been consistently estimated to be several times greater than natural mortality over the past 10 years [Hughes 2020]. Since the early-2000s, the spawning potential ratio (SPR) for Mulloway in New South Wales has been consistently estimated to be below the threshold reference point of 20 per cent with reasonable probability indicating that there may be a risk of recruitment failure [Goodyear 1993, Mace and Sissenwine 1993]. SPR for Mulloway is currently estimated to be between 10 and 27 per cent [Hughes 2020]. This SPR estimate (less than 20 per cent virgin level with reasonable probability) infers low spawning stock biomass at all plausible estimates of M. The above evidence indicates that the biomass of the part of the stock that occurs in New South Wales waters is likely to be depleted and that recruitment is likely to be impaired.

In 2013, a recovery program for Mulloway was introduced in New South Wales designed to arrest the decline in commercial and recreational Mulloway fisheries. Management changes to the recreational fishery included an increase in legal minimum length from 450 to 700 mm and a 60 per cent reduction in the daily bag limit. Management changes to the commercial fishery included the above increase in legal minimum length (with bycatch allowances of fish between 450 and 700 mm TL for the estuarine mesh net fishery) and a 500 kg trip limit for the beach-hauling net sector. In 2018, the recreational bag limit was reduced further to one fish per person and the bycatch allowance for undersized fish in the commercial estuarine mesh net fishery was removed. The above evidence indicates that current fishing mortality is constrained by management to a level that should allow the stock to recover from its recruitment impaired state; however measurable improvements are yet to be detected.

On the basis of the evidence provided above, Mulloway in New South Wales is classified as a depleted 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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