*

Vongoles are found in southern coastal waters. They occur in the intertidal zone of shallow bays and estuaries. SA has three management zones, with one zone sustainable, one undefined and one depleted. The stock in TAS is depleted. The WA stock is negligible.

Jurisdiction	Stock	Stock status	Indicators
South Australia	Coffin Bay Cockle Fishing Zone	Sustainable	Harvestable biomass estimate, recruitment
South Australia	Port River Cockle Fishing Zone	Depleted	Harvestable biomass estimate, recruitment
South Australia	West Coast Cockle Fishing Zone	Sustainable	Harvestable biomass estimate, recruitment
Tasmania	Ansons Bay Vongole Fishery	Depleted	Biomass estimate, recruitment
Western Australia	Western Australia Vongole Fishery	Negligible

Vongole (Katelysia spp.) is a species complex that inhabits southern coastal waters from Augusta in Western Australia to Port Jackson in New South Wales. They are found on sand banks in shallow bays and estuaries from the intertidal zone to a depth of five metres [Cantin 2010]. Stock structure is unknown. However, given the short larval life span, about 16 days for K. rhytiphora hatchery animals [Gluis and Li 2014], it is likely that Vongole populations in individual bays would be self-seeding and constitute functionally separate stocks.

Due to the potential for there to be a large number of stocks, assessment of stock status is presented at the management unit level—Western Australian Vongole Fishery; Ansons Bay Vongole Fishery (Tasmania); Coffin Bay Cockle Fishing Zone, Port River Cockle Fishing Zone, and West Coast Cockle Fishing Zone (South Australia).

Ansons Bay Vongole Fishery

The harvest strategy for Vongole in Tasmania in the Shellfish Fishery Policy Document [DPIW 2007] uses biomass and size-composition as performance indicators but does not define a limit reference point below which the stock would be classified as recruitment impaired. Biomass surveys of the Ansons Bay Vongole fishery are conducted every 2–3 years with total allowable commercial catches (TACCs) determined to be up to 10% of the biomass estimate (at the 95% confidence interval).

Exploitation rates have been below the maximum of 10% and minimum legal limits (32 mm shell length (SL)) are set at a size that enables the majority of Vongole to reproduce at least once prior to being available for harvest. Despite these measures, large stock declines occurred in 2014 and 2015 resulting in a fishery closure from 1 September 2015 onwards. As a result of the long term closure the licence holders have handed in their entitlements and the fishery has effectively ceased. The most recent 2021 estimate of biomass available to the Ansons Bay Vongole Fishery was 13.22 tonnes (t) (95% CI of 10.52–15.92 t), a level that is 6.5% of the peak biomass recorded in 2001. The decline of the stock from 2015 onwards is likely attributable to a combination of mortality of Vongole as a result of extreme rainfall and flood events in the north-east of Tasmania in 2014, followed by ongoing recruitment failure since that time [Keane 2021].

The above evidence indicates that the biomass of this stock is likely to be depleted and that recruitment is likely to be impaired. 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, the Ansons Bay Vongole Fishery (Tasmania) management unit is classified as a depleted stock.

Coffin Bay Cockle Fishing Zone

The harvest strategy for Vongole in the Coffin Bay Cockle Fishing Zone (CBCFZ) uses biomass as the performance indicator but does not define a limit reference point below which the stock would be classified as recruitment impaired [PIRSA 2013]. Biomass surveys of Coffin Bay have been conducted since 2013 with fishing mortality constrained by total allowable commercial catches (TACCs) determined to be up to 7.5% of the biomass estimate (at the 80% confidence interval). Based on data sampled consistently across time and space via fishery-independent surveys, harvestable biomass in the Coffin Bay Cockle Fishing Zone was stable during 2015 to 2016 but declined from 2016 to 2018. This was supported by decreasing densities of legal-sized and large Vongole and possible contraction of size frequency distributions resulting in a stock status classification of “depleting” in 2017–18 [Heldt and Mayfield 2020]. Recruitment of Vongole is sporadic [Dent et al. 2016], and the minimum legal lengths, based on estimates of size at first maturity [Dent et al. 2012; Gorman et al. 2010], enable Vongole to reproduce at least once prior to being available for harvest. The presence of sub-legal sized pre-recruits in 2018 suggested that, despite the declining trend in legal sized biomass and density, recent recruitment to the fishing ground had occurred [Heldt and Mayfield 2020]. In 2021, increased harvestable biomass suggested that the Vongole stock had improved, which was supported by increased densities of legal sized individuals and the increased incidence of survey transects with large numbers of legal sized individuals [Ferguson et al. 2022]. Additionally, there was evidence of successful recruitment in 2021 that included increased densities of sub-legal sized individuals (pre-recruits) and the strong presence of sub-legal sized individuals in size frequency distributions.

The above evidence indicates that the biomass of this stock is unlikely to be depleted and that recruitment is unlikely to be impaired. Furthermore, the above evidence indicates 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, the Coffin Bay Cockle Fishing Zone (South Australia) management unit is classified as a sustainable stock.

Port River Cockle Fishing Zone

The Port River Cockle Fishing Zone (PRCFZ) was historically important with significant catches reported prior to 2009. The first biomass survey conducted in 2009 estimated low biomass in the PRCFZ [Gorman et al. 2010], but the causes of this biomass decline are unclear. Due to ongoing sustainability concerns, the PRCFZ has been closed to the taking of Vongole by all fishing sectors since 2011–12. Biomass surveys in early 2016 showed lack of stock recovery, and a project to develop stock enhancement methods has recently been completed (Miller-Ezzy et al. 2021). The above evidence indicates that the biomass of this stock is likely to be depleted and that recruitment is likely to be impaired. Furthermore, the above evidence indicates that current fishing mortality has been reduced 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, the Port River Cockle Fishing Zone (South Australia) management unit is classified as a depleted stock.

West Coast Cockle Fishing Zone

The harvest strategy for Vongole in the West Coast Cockle Fishing Zone (WCCFZ) uses biomass as the performance indicator but does not define a limit reference point below which the stock would be classified as recruitment impaired [PIRSA 2013]. Biomass surveys of Coffin Bay have been conducted since 2013 with fishing mortality constrained by total allowable commercial catches (TACCs) determined to be up to 7.5% of the biomass estimate (at the 80% confidence interval). The three West Coast bays, comprising the WCCFZ, have been surveyed irregularly but all were surveyed in 2015 and 2021 [Ferguson et al. 2022]. Although recent surveys of individual West Coast bays have occurred in different years there is evidence that harvestable biomass has increased in each bay during 2–3 years leading up to 2021 which is supported by stable or increasing densities of legal sized individuals. Recruitment is sporadic [Dent et al. 2016], and the minimum legal lengths, based on estimates of size at first maturity [Dent et al. 2012; Gorman et al. 2010], enable Vongole to reproduce at least once prior to being available for harvest. Increased densities of sub-legal sized Vongole suggests recent recruitment in all West Coast bays [Ferguson et al. 2022]. The above evidence indicates that the biomass of this stock is unlikely to be depleted and that recruitment is unlikely to be impaired. Furthermore, the above evidence indicates 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, the West Coast Cockle Fishing Zone (South Australia) management unit is classified as a sustainable stock.

Western Australia Vongole Fishery

Stock status for the Western Australia Vongole Fishery management unit is reported as Negligible due to historically low catches and the stock has not been subject to targeted fishing. The total catch was 0.1 t or less in 2004, 2005, 2012–2014 and 2017 and zero in other years and the species is not a major component of recreational landings. Fishing is unlikely to be having a negative impact on the stock.

Vongole biology [Riley et al. 2005; Gorman et al. 2010; Dent et al. 2012] *Note that differences in maturity (50 per cent) occur among species and locations

Species	Longevity / Maximum Size	Maturity (50 per cent)
VONGOLES	29 years, 55 mm SL	4 years, 23–31 mm SL *

Distribution of reported commercial catch of VONGOLES

	Western Australia	Tasmania	South Australia
Commercial
Unspecified
Rake
Indigenous
Hand collection
Rake
Bait Pump
Recreational
Hand collection
Rake
Bait Pump

Method	Western Australia	Tasmania	South Australia
Commercial
Gear restrictions
Limited entry
Size limit
Spatial closures
Temporal closures
Total allowable catch
Indigenous
Bag limits
Size limit
Spatial closures
Recreational
Bag and possession limits
Bag limits
Size limit
Spatial closures

	Western Australia	Tasmania	South Australia
Commercial			56.19t
Indigenous		Unknown	Unknown
Recreational		Unknown	12,805 ± 12, n = 574 individuals or 0.14 t per year (2013–14)

Active Vessels. Vongole can be collected from beaches and bay on foot therefore, ‘vessels’ are not always used. Hence, numbers of licences and fishers are presented here instead of vessel numbers. Licences refer to the number of licence holders with an endorsement to take Vongole for sale.   

Commercial catch of VONGOLES - note confidential catch not shown

1. Beckmann, CL, Durante, LM, Graba-Landry, A, Stark, KE and Tracey, SR 2023, Survey of Recreational Fishing in South Australia 2021-22, Report to PIRSA Fisheries and Aquaculture, SARDI Publication No. F2022/000385-1, SARDI Research Report Series No. 1161. South Australian Research and Development Institute (Aquatic Sciences) Adelaide. 185 pp.
2. Cantin, A 2010, Population biology of two sympatric mud cockles, Katelysia peronii and K. scalarina (Bivalvia: Veneridae), with implications for their management, PhD thesis, Flinders University, Adelaide.
3. Dent, J, Mayfield, S and Carroll, J 2016, Harvestable biomass of Katelysia spp. in the South Australian commercial Mud Cockle Fishery, Report to Primary Industries and Regions South Australia, Fisheries and Aquaculture, SARDI Publication F2014/000191-2, SARDI Research Report Series 898, SARDI, Adelaide.
4. Dent, J, Mayfield, S, Burch, P, Gorman, D and Ward, TM 2012, Distribution, harvestable biomass and fisheries biology of Katelysia spp. in the South Australian commercial Mud-Cockle Fishery, Fishery assessment report for Primary Industries and Regions South Australia Fisheries and Aquaculture, SARDI Publication F2010/000263-2, SARDI Research Report Series 595, South Australian Research and Development Institute (Aquatic Sciences), Adelaide.
5. Department of Primary Industries and Water 2007, Shellfish fishery policy document, Wild Fisheries Management Branch, DPIW, Hobart.
6. Ferguson, G, Heldt, K, Stobart, B, Mayfield, S 2022, Harvestable biomass in the South Australian Vongole Fishery (Katelysia spp.). Report to PIRSA Fisheries and Aquaculture. SARDI Publication No. F2014/000191-3. SARDI Research Report Series No. 1127. 37 pp.
7. Gluis, MR and Li, X 2014, Hatchery manual for larval rearing of Vongole Katelysia rhytiphora, Fisheries Research and Development Corporation Project 2009/208, South Australian Research and Development Institute (Aquatic Sciences), Adelaide.
8. Gorman, D, Mayfield, S, Burch, P and Ward, TM 2010, Distribution, harvestable biomass and fisheries biology of Katelysia spp. In the South Australian commercial mud cockle fishery, Fishery assessment report for PIRSA Fisheries, SARDI Publication F2010/000263-1, SARDI Research Report Series 442, South Australian Research and Development Institute (Aquatic Sciences), Adelaide.
9. Heldt, K and Mayfield, S 2020, Harvestable biomass of Katelysia spp. in the South Australian Vongole Fishery. Report to PIRSA Fisheries and Aquaculture. South Australian Research and Development Institute (Aquatic Sciences), Adelaide. SARDI Publication Number. F2014/000191-2. SARDI Research Report Series No. 1060. 40pp
10. Keane, J 2021, 2021 Small Bivalve Fishery Assessment - Katelysia scalarina - Ansons Bay, Institute for Marine and Antarctic Studies Report, University of Tasmania, Hobart.
11. Keane, JP and Gardner, C 2017, 2017 Small Bivalve Fishery assessment. Institute for Marine and Antarctic Studies Report, University of Tasmania, Hobart.
12. Miller-Ezzy, PA, Stone, DAJ and Li, X 2021, Mud Cockle (Katelysia spp.) stock enhancement / restoration, Practical implementation and policy evaluation, Final Report for FRDC Project No. 2014/028, South Australian Research and Development Institute (Aquatic Sciences). 61 pp.
13. Primary Industries and Regions South Australia 2013, Management plan for the South Australian Commercial Marine Scalefish Fishery, South Australian Fisheries Management Series: Paper 59, PIRSA, Adelaide.
14. Riley, SP, Green, RM, Zacharin, W and Maguire, GB 2005, Growth models and age determination for the intertidal venerid clam Katelysia scalarina (Lamarck 1818) from three sites in Tasmania, Australia, Fisheries Research and Development Corporation Project 93/232, in GB Maguire (ed) Enhancing Tasmanian clam resources, FRDC, Tasmania.