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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.

Northern Territory

Brownstripe Snapper is mainly caught and discarded as bycatch by the Northern Territory's Demersal Fishery's finfish trawl gear due to their small size. There are uncertainties around their biomass removals with potential misidentification as other snapper species. Similar to other trawl caught Lutjanid species, Brownstripe Snapper had their highest catches during the late 1980s when foreign fishing fleets were fishing in NT waters and recent development in the Demersal Fishery has seen catches increase to these historical levels (approximately 30 t) with an average annual catch of 20 t in the last 10 years. Relative biomass estimates from recent fishery independent surveys indicate approximately 1,490 t in the Northern Territory [Knuckey and Koopman 2022]. The harvest fraction in 2022 is less than 1% of the estimated biomass which indicates a relatively low fishing pressure. A preliminary assessment using catch data applied to a modified catch-MSY model (developed by Martell and Froese [2013] and modified by Haddon et al. [2018]), estimated that the 2022 biomass of Brownstripe Snapper was around the MSY reference levels [Pazhayamadom 2022] suggesting that the biomass of this stock is unlikely to be depleted and that recruitment is unlikely to be impaired. Similarly, the fishing mortality in 2022 was estimated to be around the target level of 0.22 indicating 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, Brownstripe Snapper in the Northern Territory is classified as a sustainable 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

1. Anderson, WD and Allen, GR 2001, Lutjanidae. FAO species identification guide for fisheries purposes. The living marine resources of the Western Central Pacific, Vol. 5, Part 3 (ed. by Carpenter, KE and Niem, VH), pp. 2840–2918, Food and Agriculture Organization of the United Nations, Rome.
2. Haddon M, Punt, A and Burch, P 2018, simpleSA: A package containing functions to facilitate relatively simple stock assessments. R package version 0.1.18.
3. Knuckey, IA and Koopman, M 2022, Survey of tropical snapper in Northern Territory fisheries - 2021, Fishwell Consulting.
4. Martell, S and Froese, R 2013, A simple method for estimating MSY from catch and resilience. Fish and Fisheries 14:504–514.
5. Newman, SJ, Brown, JI, Fairclough, DV, Wise, BS, Bellchambers, LM, Molony, BW, Lenanton, RCJ, Jackson, G, Smith, KA, Gaughan, DJ, Fletcher, WJ, McAuley, RB and Wakefield, CB 2018, A risk assessment and prioritisation approach to the selection of indicator species for the assessment of multi-species, multi-gear, multi-sector fishery resources. Marine Policy, 88: 11–22.
6. Newman, SJ, Cappo, M, and Williams, DM 2000, Age, growth and mortality of the stripey, Lutjanus carponotatus (Richardson) and the brown-stripe snapper, L. vitta (Quoy and Gaimard) from the central Great Barrier Reef, Australia, Fisheries Research, 48: 263-275
7. Palla HP and Sotto, FB 2021, Reproductive biology of brownstripe snapper Lutjanus vitta (Quoy and Gaimard, 1824) from West Sulu Sea, Philippines, Egyptian Journal of Aquatic Research 47, 67–73.
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.