*

Australia has four stocks of Commercial Scallop. Two are sustainable – the Bass Strait Central Zone Scallop Fishery and the Port Phillip Bay Dive Scallop Fishery. One is classified as depleted (Victoria’s Ocean Scallop Fishery), and one is classified as a recovering stock (the Tasmanian Scallop Fishery).

There are several Commercial Scallop bed regions fished commercially in Commonwealth, Victorian and Tasmanian waters. Commercial Scallops in Port Phillip Bay (Victoria) and D’Entrecasteaux Channel (Tasmania) are genetically distinct from conspecifics in most other locations in south-eastern Australia [Woodburn 1990; Semmens et al. 2015; Ovenden et al. 2016]. Beds in north-eastern Bass Strait are also genetically distinct to adjacent Bass Strait beds and may not contribute to wider recruitment based on biophysical models of larval movement [Ovenden et al. 2016].  

Here, assessment of stock status is reported at the management unit level—Bass Strait Central Zone Scallop Fishery (Commonwealth), Ocean Scallop Fishery (Victoria), Port Phillip Bay Dive Scallop Fishery (Victoria) and Tasmania Scallop Fishery.

Bass Strait Central Zone Scallop Fishery

Commercial Scallops in the Commonwealth Bass Strait Central Zone Scallop Fishery (BSCZSF) were considered recruitment overfished between 1999 and 2007. Following three years of closure due to low scallop abundance and concerns about overfishing, the fishery was reopened in 2009, under a new harvest strategy [AFMA 2007]. Commercial Scallops experienced die-offs in 2010–11 and the harvest strategy was revised in 2012 [AFMA 2012], 2014 [AFMA 2014] and 2015 [AFMA 2015]. The main areas fished have varied through time. Between 2009 and 2013 the fishery operated north of Flinders Island (eastern Bass Strait), but then shifted to focus around King Island (western Bass Strait) until 2019, and has since operated in both areas.

Elements of the current Commonwealth harvest strategy include: a tiered management approach, whereby a 150 tonne (t) total allowable catch (TAC) can be set as a ‘default opening’ TAC. This TAC, which covers the whole BSCZSF management area, allows operators to search widely for scallop beds, and a pre-season scientific biomass survey to be conducted.  

Tier 1 of the harvest strategy states that if the scientific survey identifies one or more scallop bed(s) with a combined biomass of 1,500 t or more, with scallops greater than 85 mm in length and in ‘high’ density, and these beds are closed to commercial fishing, the TAC can be stepped up to a maximum of 2,000 t.  

Tier 2 of the harvest strategy states that if the scientific survey identifies one or more scallop bed(s) with a combined biomass of 3,000 t or more, and these beds are closed to commercial fishing, the TAC can be set to at least 2,000 t.

The 2021 biomass survey covered six King Island beds with an estimated combined biomass of 30,278 t, three Apollo Bay beds with an estimated combined biomass of 20,582 t and three Flinders Island beds with an estimated biomass of 13,142 t [Koopman et al. 2021]. The total estimated biomass of 64,000 t comprised 56,067 t of scallops larger than 85 mm.

The 2021 fishery opened on 12 July 2021 with a TAC of 3,905 t (up from 3,000 t in 2020). Fishing focused on beds in both eastern and western Bass Strait and operators reported scallops in good condition. The fishery closed on 31 December 2021 with 2,344 t landed (2,732 t in 2020).  

The management of scallops is complex due to the high degree of variation in recruitment from year to year. Recent survey and catch information indicate that the biomass is substantially higher now than it was a decade ago and is currently not depleted in managed areas across the fishery. The recent management arrangements (including TACs set) have ensured that recent catches are low relative to recent surveyed biomass. While it is very difficult to predict future recruitment in scallop fisheries, low TACs set in recent years have helped maintain a healthy biomass and minimised the chance of the stock becoming recruitment impaired due to fishing [Bromhead et al. 2022]. The above evidence indicates that the biomass of this stock is unlikely to be depleted and recruitment is unlikely to be impaired, and the current level of fishing mortality is unlikely to cause the stock to become recruitment impaired.

On the basis of the evidence provided above, the Bass Strait Central Zone Scallop Fishery (Commonwealth) management unit is classified as a sustainable stock.

Commercial Scallop biology [Young et al. 1989; Woodburn 1990; Semmens et al. 2015; Ovenden et al. 2016]

Distribution of reported commercial catch of Commercial Scallop

Commonwealth – Commercial (Catch). Data provided for the Commonwealth align with the Commonwealth Bass Strait Central Zone Scallop Fishery for 2021.

Commonwealth – Recreational. The Australian Government does not manage recreational fishing in Commonwealth waters. Recreational fishing in Commonwealth waters is managed by the state or territory immediately adjacent to those waters, under its management regulations. Recreational fishing sectors in the Indian Ocean are South Australia, Victoria and Western Australia. Recreational sectors in the Pacific Ocean are New South Wales, Queensland and Tasmania.

Commonwealth – Indigenous. The Australian Government does not manage non-commercial Indigenous fishing in Commonwealth waters, with the exception of the Torres Strait. In general, non-commercial Indigenous fishing in Commonwealth waters is managed by the state or territory immediately adjacent to those waters. Indigenous fishing sectors in the Indian Ocean are South Australia, Victoria and Western Australia.

Victoria – Commercial (Catch). (a) To protect commercial confidentiality of data, the catch in the Ocean Scallop Fishery (Victoria) and Port Phillip Bay Dive Scallop Fishery (Victoria) cannot be reported because there are fewer than five licence holders; and (b) In Victoria, the reporting period is fishing season, which runs from 1 April–30 March.

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. 

Commercial catch of Commercial Scallop - note confidential catch not shown

1. AFMA 2007, Harvest strategy for the Bass Strait Central Zone Scallop Fishery, Australian Fisheries Management Authority, Canberra.
2. AFMA 2012, Harvest strategy for the Bass Strait Central Zone Scallop Fishery, Australian Fisheries Management Authority, Canberra.
3. AFMA 2014, Harvest Strategy for the Bass Strait Central Zone Scallop Fishery, Australian Fisheries Management Authority, Canberra.
4. AFMA 2015, Harvest Strategy for the Bass Strait Central Zone Scallop Fishery, Australian Fisheries Management Authority, Canberra.
5. Bromhead, D, Blake, S and Curtotti, R, 2022, Bass Strait Central Zone Scallop Fishery, in Patterson, H, Bromhead, D, Galeano, D, Larcombe, J, Timmiss, T, Woodhams, J and Curtotti, R (eds), Fishery status reports 2022, Australian Bureau of Agricultural and Resource Economics and Sciences, Canberra.
6. Coleman, N 1998, Counting scallops and managing the fishery in Port Phillip Bay, south-east Australia, Fisheries Research, 38: 145–157.
7. Conron, SD, Bell, JD, Ingram, BA and Gorfine, HK 2020, Review of key Victorian fish stocks — 2019, Victorian Fisheries Authority Science Report Series No. 15, First Edition, November 2020, VFA, Queenscliff, 176 pp.
8. DEPI 2013, Commercial Scallop Dive Fishery (Port Phillip Bay) Baseline Management Arrangements, Fisheries Victoria, Melbourne.
9. Ewing, G, Moreno, D, Kilpatrick, R, Dudgeon, A and Semmens, J 2021, 2021 Tasmanian Scallop Fishery Pre Season Survey Report, Institute for Marine and Antarctic Studies, University of Tasmania.
10. Gwyther, D 2015, Review of The TACC For the Dive Fishery for Scallops in Port Phillip Bay – Report to Port Phillip Bay Scallops, 27 March 2015, Melbourne, Picton Group Pty Ltd, 6 pp.
11. Harrington, J, Leporati, S and Semmens, JM 2010, 2009 Victorian Scallop Fishery Survey, final report to Fisheries Victoria. Tasmanian Aquaculture and Fisheries Institute, University of Tasmania, Hobart.
12. Koopman, M, Knuckey, I and Hanley, M 2021, Eastern Victorian Ocean Scallop Fishery 2020 survey of “Tarwhine” scallop bed, Report to the Victorian Fisheries Authority, Fishwell Consulting, 9 pp.
13. Koopman, M, Knuckey, I and Hudson, R 2022, Eastern Victorian Ocean Scallop Fishery 2022 Pre-season Abundance Survey, Report to the Victorian Fisheries Authority, Fishwell Consulting, 39 pp.
14. Koopman, M, Knuckey, I and Hudson, R 2023, Eastern Victorian Ocean Scallop Fishery 2023 Pre-season Abundance Survey, Report to the Victorian Fisheries Authority, Fishwell Consulting, 28 pp.
15. Koopman, M, Knuckey, I, Harris, M and Hudson, R 2018, Eastern Victorian Ocean Scallop Fishery – 2017-18 Abundance Survey, Report to the Victorian Fisheries Authority, Fishwell Consulting, 42pp.
16. Ovenden, JR, Tillett, BJ, Macbeth, M, Broderick, D, Filardo, F, Street, R, Tracey, SR and Semmens, J 2016, Stirred but not shaken: population and recruitment genetics of the scallop (Pecten fumatus) in Bass Strait, Australia, ICES Journal of Marine Science, 73(9): 2333–2341.
17. Semmens, J, Ewing, G and Keane, J 2018, Tasmanian Scallop Fishery Assessment 2017, Institute for Marine and Antarctic Studies, 34 pp.
18. Semmens, JM and Jones, N 2012, Victorian scallop fishery survey final report, Institute for Marine and Antarctic Studies, University of Tasmania, Hobart.
19. Semmens, JM, Ovenden, JR, Jones, NAR, Mendo, TC, Macbeth, M, Broderick, D, Filardo, F, Street, R, Tracey, SR and Buxton, CD 2015, Establishing fine-scale industry based spatial management and harvest strategies for the Commercial Scallop fishery in South East Australia, final report to the Fisheries Research and Development Corporation, project 2008/022, FRDC, Canberra.
20. Woodburn, L 1990, Genetic variation in southern Australian Pecten, in Proceedings of the Australasian Scallop Workshop, Tasmanian Government, Hobart.
21. Young, P and Martin, R 1989, The scallop fisheries of Australia and their management. Reviews in Aquatic Sciences, 1(4): 615–638.