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Brownstripe Snapper is widely distributed throughout northern Australia. The WA and NT jurisdictional stocks are classified as sustainable. The Gulf of Carpentaria management unit (QLD) and the QLD East Coast management unit are undefined with limited information available.

Image courtesy of Queensland Government

Brownstripe Snapper is widely distributed throughout the western Pacific and eastern Indian Ocean region, ranging from New Caledonia and the Gilbert Islands to southern India, extending northwards to southern Japan and is also found in the Seychelles (Anderson and Allen 2001). In Australian waters, Brownstripe Snapper occurs from the Houtman Abrolhos Islands in Western Australia, around the northern coast to Moreton Bay in southern Queensland.

There is little information on biological stock structure and population connectivity for this species in Australian waters. Brownstripe Snapper is broadly distributed across the continental shelf at depths ranging from 20 to 120 m, with a dispersal capacity via a pelagic egg and larval phase that may contribute to widespread gene flow. However, geographic separation of some populations and the likelihood of limited adult movement suggests separate management units are appropriate.

Here, assessment of stock status is presented at the jurisdictional level—Western Australia and Northern Territory—and the management unit level—Gulf of Carpentaria (Queensland) and East Coast Queensland.

East Coast Queensland

Brownstripe Snapper is harvested as a part of the Reef Line Fishery (RLF) in Queensland where catch is constrained by a multi-species TACC. In early 2020, the management regime was developed further with the introduction of a Harvest Strategy for the fishery. For secondary target and by-product species like Brownstripe Snapper, this includes species-specific harvest control rules and catch reference points that trigger stock assessments and the implementation of species-specific TACCs [QDAF 2020]. In addition to the Harvest Strategy, Brownstripe Snapper are managed by minimum legal size limits that align with their reproductive biology (i.e., size at sexual maturity) [Ramachandran et al. 2014]. To date, no formal stock assessments have been undertaken to quantify biomass levels of Brownstripe Snapper on the east coast of Australia.

Brownstripe Snapper can be reported at the species level (Brown Hussar, Lutjanus vitta), however over 99% of commercial catch is recorded under the Hussar Unspecified complex. This catch category includes two species; Hussar (Lutjanus adetii) and Brownstripe Snapper (Lutjanus vitta) for which the relative species composition is unknown. Commercial catch recorded against this category was historically much higher than in recent years; between 1995–96 and 2002–03 average annual catch was 89 tonnes (t) (range 64–110 t). Catch declined sharply (79%) following the expansion of no-take marine reserves within the Great Barrier Reef Marine Park and the introduction of a quota management system for coral reef finfish species. Catch dropped to an average of 24 t from 2003–13 before stabilising at an average of 14 t over the last decade. Notably the catch was low in 20222 at 4 t, although this drop was associated with a decrease in fishing days from 1,447 days per year in 2020–21 to 675 fishing days per year in 2021–22 suggesting the decrease in catch is likely a result of fisher behaviour and not a result of a decrease in biomass. The recreational sector also contributes to Hussar Unspecified fishing mortality (44,000 fish; 2019–20 estimate) [Teixeira et al. 2021]. There is insufficient information available to confidently classify the status of this stock.

On the basis of the evidence provided above, East Coast Queensland management unit is classified as an undefined stock.  

Gulf of Carpentaria

Brownstripe Snapper is harvested as a minor by-product species by trawl (Gulf of Carpentaria Developmental Fin Fish Trawl Fishery) (GOCDFFTF) and line (Gulf of Carpentaria Line Fishery) in the Gulf of Carpentaria (Queensland). Apart from a minimum legal size and recreational possession limit, there are no other constraints to fishing pressure for this species. In both commercial fisheries, Brownstripe Snapper has been harvested in negligible amounts (< 1 t per year) and the trawl fishery as a whole has been largely inactive since 2016. There are no reliable estimates of recreational harvest for this stock of Brownstripe Snapper however it is likely to be minor. There is insufficient information available to confidently classify the status of this stock.

On the basis of the evidence provided above, Gulf of Carpentaria management unit is classified as an undefined stock.  

Brownstripe Snapper biology [Newman et al. 2000; Palla and Sotto 2021; Ramachandran et al. 2014]

Distribution of reported commercial catch of Brownstripe Snapper

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

Queensland – Commercial (Catch). Queensland commercial and charter data have been sourced from the commercial fisheries logbook program. Further information available through the Queensland Fisheries Summary Report https://www.daf.qld.gov.au/business-priorities/fisheries/monitoring-research/data/queensland-fisheries-summary-report 

Queensland – Recreational Fishing (Catch). Data based at the whole of Queensland level and derived from statewide recreational fishing surveys. Where possible, estimates have been converted to weight (tonnes) using best known conversion multipliers. Conversion factors may display regional or temporal variability. In the absence of an adequate conversion factor, data presented as number of fish. 

Western Australia. Active Vessels data is unreportable as there were fewer than three vessels operating in Pilbara Fish Trawl Interim Managed Fishery and Pilbara Trap Managed Fishery.

Western Australia – Recreational (Catch). Boat-based recreational catch is from 1 September 2020–31 August 2021. These data are derived from those reported in Ryan et al. [2022]. Shore based catches of Mangrove Jack are not known.

Western Australia – Recreational (management methods). A Recreational Fishing from Boat License is required for the use of a powered boat to fish or to transport catch or fishing gear to or from a land-based fishing location.

Western Australia – Indigenous (management methods). Subject to application of 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.

Commercial catch Brownstripe Snapper - note confidential catch not shown

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8. Pazhayamadom, DG 2022, Northern Territory Brownstripe Snapper (Lutjanus vitta) stock status summary—2022 (unpublished fishery report)
9. Queensland Department of Agriculture and Fisheries 2020, Reef line fishery harvest strategy: 2020–2025. Brisbane, Queensland.
10. Ramachandran, S, Ali, DM, and Varghese, BC 2014, Age, growth and maturity of brown stripe snapper Lutjanus vitta (Quoy & Gaimard, 1824) from southwest coast of India, Journal of Marine Biology Association India, 55(2): 61–68.
11. Ryan, KL, Lai, EKM and Smallwood, CB 2022. Boat-based recreational fishing in Western Australia 2020/21, Fisheries Research Report No. 327 Department of Primary Industries and Regional Development, Western Australia. 221pp.
12. Teixeira, D, Janes, R, and Webley, J 2021, 2019–20 Statewide Recreational Fishing Survey Key Results, Project Report. State of Queensland, Brisbane.
13. Wakefield, C, Trinnie, F, Skepper, C, Boddington, Newman, SJ, and Steele, A 2023, North Coast Demersal Resource Status Report 2022, pp. 167–176. In: Gaughan, D.J. and Santoro, K. (eds.), 2023, Status Reports of the Fisheries and Aquatic Resources of Western Australia 2021/22: The State of the Fisheries, Department of Primary Industries and Regional Development, Western Australia, Perth, Australia.