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Dusky Flathead is an inshore and estuary fish found in QLD, NSW and VIC. Stocks in QLD and NSW are sustainable, while the VIC stock is undefined.

The biological stock structure of Dusky Flathead populations is unknown.

In the absence of information on biological stock boundaries, here assessment of stock status is presented at the jurisdictional level—Queensland, New South Wales and Victoria.

Victoria

Until its recent closure, the Gippsland Lakes Fishery was the only remaining Victorian fishery to commercially harvest Dusky Flathead. Recreational anglers continue to catch the species in the Gippsland Lakes, and in various eastern Victorian estuaries. Catch information is only available for the Gippsland Lakes, and, Mallacoota Inlet, and Lake Tyers. This assessment therefore focuses on those locations.

The impact of fishing pressure on stock biomass was evaluated using recreational CPUE and size composition data from fishers participating in an angler diary program [Conron and Oliveiro 2016]. The CPUE obtained from angler diarists showed a declining trend in Gippsland Lakes over almost two decades noting the low sample sizes and associated high uncertainty in the data [Conron et al. 2020]. Angler diarist CPUE declined in Mallacoota Inlet from 1999–2011, before stabilising at around one fish per angler hour through until 2018–19 [Hamer et al 2019, Conron et al. 2020]. The CPUE of angler diarists in Lake Tyers increased from 1999–2004 and was highly variable throughout the 2000s. From 2010, there was a consistent decline in CPUE from around 2.5 fish per hour to less than 1.0 fish per hour [Conron et al. 2020]. Elevated CPUE during 2004–2009 from angler diarists in Mallacoota Inlet was likely reflective of a strong recruitment event. Nevertheless, the time series is too brief to determine if this is part of the boom-bust cycle of recruitment that characterises this species [Hamer et al 2019; Hicks et al. 2015] or represents an ongoing depleted state in which recruitment has become impaired. A reduction in participation in the angler diary program has increased the uncertainty of angler diarist CPUE in recent years [Conron et al. 2020].

There is no direct measure of recreational fishing pressure for the Gippsland Lakes, Mallacoota Inlet and Lake Tyers estuarine systems. From 2003, slot limit regulations and reduced bag limits were introduced in Victoria specifically for Dusky Flathead to ameliorate the risks of overfishing. The regulations have been refined over time as more information became available, with the current regulations (minimum legal length 30 cm, maximum legal length 55cm, daily bag limit of 5) being established in 2012 [Hamer et al. 2019].

On balance, insufficient information exists to confidently determine stock status.  Recreational catch rates (CPUE) have stabilised since 2014, however, future trends are uncertain as there is a lack of reliable information of recent recruitment.    

On the basis of the evidence provided above, Dusky Flathead in Victoria is classified as an undefined stock.

Dusky Flathead biology [Gray and Barnes 2015, Hicks et al. 2015, Kailola et al. 1993]

Distribution of reported commercial catch of Dusky Flathead

Queensland – Indigenous (Management Methods) please refer to https://www.daf.qld.gov.au/business-priorities/fisheries/traditional-fishing  

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

Victoria – Indigenous (Management Methods) A person who identifies as Aboriginal or Torres Strait Islander is exempt from the need to obtain a Victorian recreational fishing licence, provided they comply with all other rules that apply to recreational fishers, including rules on equipment, catch limits, size limits and restricted areas. Traditional (non-commercial) fishing activities that are carried out by members of a traditional owner group entity under an agreement pursuant to Victoria’s Traditional Owner Settlement Act 2010 are also exempt from the need to hold a recreational fishing licence, subject to any conditions outlined in the agreement. Native title holders are also exempt from the need to obtain a recreational fishing licence under the provisions of the Commonwealth’s Native Title Act 1993.

Commercial catch of Dusky Flathead - note confidential catch not shown

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