*

Giant Crab occurs from WA to TAS with weakly connected stocks throughout this range. The stock associated with each cluster of fishing is assessed here. The Western Australian and South Australian stocks are sustainble. The stock West of Bass Strait is recovering. The stock East of Tasmania is undefined due to limited fishing and data.

Giant Crab is continuously distributed across its range from Western Australia to East of Tasmania. Movement of giant crab post-settlement is limited. Planktonic larval duration is around 50 days, with larval release occurring along the edge of the continental shelf. The shelf is a high current area, facilitating dispersal, and oceanographic modelling has indicated that Giant Crab dispersal occurs over reasonably large spatial scales [Gardner 1998; Gardner and Quintana 1998; Williams et. al. 2009]. However, given the large spatial scale of the distribution and features that disrupt dispersal (such as the Bass Strait) the species is likely to consist of a series of local populations with moderate connectivity within the meta population. An FRDC project is currently underway which will provide further clarification on stock structure for future assessments (FRDC Project 2021-025 Resolving the biological stock structure of Southern Ocean crab fisheries).

Fishing occurs in four spatial clusters which are sufficiently separated that each cluster is likely to be fishing a local stock that has a low level of connectivity with the other stocks. The stock "West of Bass Strait" is fished by both Victoria and Tasmania. This stock previously had differing assessments for the two jurisdictions which resulted in an assessment on a jurisdictional basis. However, these differences have now been resolved. Consequently, assessment of stock status is presented here at the biological-stock level—Eastern Tasmania, South Australia, West of Bass Strait, and Western Australia.

Eastern Tasmania

Giant crab catches on the East Coast of Tasmania averaged 20 tonnes (t) from 2000 to 2011 [Emery et. al. 2015]. Reductions in the statewide total allowable commercial catch (TACC), in conjunction with fleet changes resulted in a disproportionate reduction of catch on the East Coast. Catches have been less than 11 t since 2012, and less than 1 t in the last two years. 

The reductions in catch per unit effort (CPUE) across Tasmania that led to TACC reductions from 2012 onwards were also observed for the Eastern Tasmanian stock. Consequently during this period, the stock was depleting and possibly depleted. In recent years insufficient fishing has taken place for the Eastern Tasmanian CPUE to provide a meaningful indicator of stock status. The same input controls are in place for the Eastern Tasmanian stock as for the Tasmanian fishery West of Bass Strait. In conjunction with low catches this indicates that recovery from the reduced stock observed in the years following 2010 is possible, however there is no evidence to indicate whether recovery has taken place and due to the long generational time of giant crab this can be a slow process.

Due to the lack of available information the Eastern Tasmanian Giant Crab biological stock is classified as an undefined stock.

Giant Crab biology [Gardner 1998; McGarvey et. al. 1999; Williams et. al. 2009,]

Distribution of reported commercial catch of Giant Crab

South Australian data are from quota holders in the 2016–17 fishing season (October 2016–May 2017), Victorian data are for the 2021–22 fishing season (November 2021–September 2022), Tasmanian data are for the 2022-23 fishing season (March 2022 – February 2023) and South Coast Crustacean Managed Fishery (Western Australia) data are for the 2019–20 financial year. 

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 fishinglicence under the provisions of the Commonwealth’s Native Title Act 1993.

Commercial catch of Giant Crab - note confidential catch not shown

1. Emery, T, Hartmann, K and Gardner, C 2015, Giant Crab stock assessment report 2013/14, IMAS, Hobart.
2. Fisheries Victoria 2010, Giant Crab Management Plan, Second Edition, ISBN 978-1-74264-478-3.
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9. PIRSA 2018, Management Policy for Commercial Fishing of Giant Crabs in South Australia. Primary Industries and Regions South Australia. Adelaide, Australia.
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