Southern Rocklobster Jasus edwardsii

Adrian Linnanea, Caleb Gardnerb and Terry Walkerc

Southern Rock Lobster

Table 1: Stock status determination for Southern Rocklobster


South Australia, Tasmania, Victoria


South-eastern Australian

Stock status





Percentage of egg production relative to unfished level, proportion of spawning stock protected by minimum size limits

RLF [TAS] = Rock Lobster Fishery (Tasmania); RLF [VIC] = Rock Lobster Fishery (Victoria); SRLF = Southern Rock Lobster Fishery (South Australia)

Stock Structure

Southern Rocklobster is a single biological stock across south-eastern Australia.

Stock Status

The biological stock status determination for Southern Rocklobster (Jasus edwardsii) is based on egg production outputs from a combined stock assessment model1 for South Australia, Victoria and Tasmania. Combined outputs of the most recent assessments2–5  estimate that egg production in 2010–11 was 23 per cent of the unfished level. Accepting a limit reference point of 20 per cent of the unfished level, the biological stock is not considered to be recruitment overfished.

Fishing mortality, combined with low recruitment, led to a steady decline in egg production from 2002 to 2008. Total allowable commercial catches (TACCs) were reduced in response, and egg production began to recover in 2009. Current levels of fishing mortality are unlikely to cause the biological stock to become recruitment overfished.

On the basis of the evidence provided above, the biological stock is classified as a sustainable stock.

Table 2: Southern Rocklobster biology6–8

Longevity and maximum size

20+ years; >20 cm CL

Maturity (50%)

5.9–12.2 cm CL, depending on region

CL = carapace length

Figure 1: Distribution of reported commercial catch of Southern Rocklobster in Australian waters, 2010
Figure 1: Distribution of reported commercial catch of Southern Rocklobster in Australian waters, 2010

Main features and statistics for Southern Rocklobster stocks/fisheries in Australia in 2010
  • Southern Rocklobster can be fished using baited traps, dillies and drop nets. Recreationally, they can also be taken by hand or snares when using scuba; it is an offence to take Southern Rocklobster using a spear, hook or other pointed instrument.
  • The biological stock is managed by South Australia, Tasmania and Victoria using a range of input and output controls:
    • Input controls include limited entry, and spatial and temporal closures.
    • Output controls include bag limits, size limits, TACCs and individual transferable quotas.
  • The total number of fishing vessels in the Southern Rocklobster fishery for the 2010 season was 543, with 227 vessels in South Australia, 86 in Victoria and 230 in Tasmania.
  • The total amount of Southern Rocklobster caught commercially in Australia in 2010 was 3083 tonnes (t), comprising 1556 t in South Australia, 1225 t in Tasmania and 302 t in Victoria. Recreational catches in all states are estimated at less than 10 per cent of commercial catch. Indigenous catch is estimated to be far smaller than the recreational catch and has negligible impact on Southern Rocklobster abundance

a) Commercial catch of Southern Rocklobster in Australian waters, 2001–02 to 2010–11 (financial year)
b) percentage of egg production relative to unfished level across south-  eastern Australia, 1970–2010 (fishing season)
Figure 2: a) Commercial catch of Southern Rocklobster in Australian waters, 2001–02 to 2010–11 (financial year);
b) percentage of egg production relative to unfished level across south-  eastern Australia, 1970–2010 (fishing season)

Catch Explanation

The TACC for Southern Rocklobster has been reduced from 4227 t in 2007 to 3083 t in 2010 (Figure 2a). This management action was in response to a period of below-average recruitment of juvenile Southern Rocklobster into the legal-sized biological stock across the broad region9. The below-average recruitment was not associated with low egg production, but rather unusual oceanographic patterns affecting larval development and growth. The management response was to reduce catch, with the objective of increasing stock abundance and catch rates; this is important for managing costs of fishing in this industry. This management action appears to have been successful, since the latest stock assessments show improvements in biological stock abundance.

Effects of fishing on the marine environment
  • In South Australia, concern has been expressed about potential interactions with Australian Sea Lions in the fishery, specifically the risk of juvenile pups entering pots10. Sea lion excluder devices are routinely fitted into pots in areas where interactions are likely to occur.
  • Whale entanglements are recognised as a management issue by the Victorian Southern Rock Lobster Fishery Management Plan11, which has responded with a fishery code of practice to prevent and respond to whale entanglements.
  • The Southern Rocklobster biological stock is being rebuilt off eastern Tasmania to assist in the management of Long-spined Sea Urchins2,12. These urchins, which have extended their range southwards from New South Wales, can create barren patches of reef through overgrazing. Rebuilding the Southern Rocklobster biological stock may reduce barren formation through predation on the urchins.
  • Habitat impacts of gear have been researched and assessed as being of negligible risk13.

Environmental effects on Southern Rocklobster
  • The potential impact of climate change on recruitment, growth and mortality has been identified as a risk across the range of the species14.
  • Recruitment, catchability and growth can vary substantially from year to year as a result of environmental changes, including water temperature and movement of oceanic currents9. As mentioned above, below-average recruitment is not necessarily associated with low egg production, but can result from unusual oceanographic patterns that can affect larval development and growth.

South Australian Research and Development Institute
b Institute for Marine and Antarctic Studies, Tasmania
c Department of Primary Industries, Victoria