Southern Rock Lobster Jasus edwardsii

Adrian Linnanea, Caleb Gardnerb, David Reillyc and ​Jason Howd


Southern Rock Lobster

Table 1: Stock status determination for Southern Rock Lobster

Jurisdiction

South Australia, Tasmania, Victoria, Western Australia

Stock

Southern Australian

(SASRLF, TRLF, VRLF, WASCCF)

Stock status

Sustainable

Indicators

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


SASRLF = South Australian Southern Rock Lobster Fishery; TRLF = Tasmanian Rock Lobster Fishery; VRLF = Victorian Rock Lobster Fishery; WASCCF = Western Australian South Coast Crustacean Fisheries (Western Australia)


Stock Structure

Southern Rock Lobster is considered to be a single biological stock across southern Australia because the species occurs in a continuous distribution across this range and has extensive larval dispersal; genetic analyses also indicate that it is a single stock1. The larval duration is around 12–18 months. Larval release occurs across the southern continental shelf, which is a high-current area, facilitating dispersal. Oceanographic modelling has also indicated that Southern Rock Lobster dispersal occurs over large spatial scales, indicating that there is a single stock2. Southern Rock Lobster is reported at the level of the biological stock.


Stock Status

Southern Australian biological stock

The stock status determination for Southern Rock Lobster is based on egg production outputs from a combined stock assessment model3 for South Australia, Victoria and Tasmania. Combined outputs of the most recent assessments estimate that egg production in 2012–13 was 22 per cent of the unfished level4–7. Accepting a limit reference point of 20 per cent of the unfished level, the stock is not considered to be recruitment overfished.

Total allowable commercial catches have been reduced across south-eastern Australia over the past decade in response to decreases in catch rates, which reflect declines in rock lobster abundance. Current levels of fishing mortality are unlikely to cause the 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 biology8–10

Longevity and maximum size

20+ years; >200 mm CL

Maturity (50%)

59–122 mm CL, depending on region

CL = carapace length


Figure 1: Distribution of reported commercial catch of Southern Rock Lobster in Australian waters in 2012–13 (fishing season)
Figure 1: Distribution of reported commercial catch of Southern Rock Lobster in Australian waters in 2012–13 (fishing season)

Note: Fishing seasons are October 2012 – May 2013 (South Australia), November 2012 – September 2013 (Victoria), November 2012 – September 2013 (Tasmania) and November 2012 – June 2013 (Western Australia south coast).




Table 3: Main features and statistics for Southern Rock Lobster fisheries in Australia, 2012–13 (fishing season)

Jurisdiction

South Australia

Victoria

Tasmania

Western Australia

Fishing methods

Commercial

Baited traps

Recreational

Baited traps

Hoop/drop nets

Diving and hand collection

Indigenousa,b

Baited traps

Hoop nets

Diving and hand collection

Management methods

Commercial

Limited entry

Size limits

Total allowable catch

Temporal closures

Spatial closures

Gear restrictions

Recreational

Bag limits

Size limits

Temporal closures

Spatial closures

Gear restrictions

Indigenousa,b

Bag limits

Size limits

Active vessels

207 in SASRLF

71 in VRLF

202 in TRLF

28 in WASCCF

Catch

Commercial

1552 t in SASRLF

306 t in VRLF

1064 t in TRLF

45 t in WASCCF

Recreational

Unknown

Unknown

84 t

<5 t

Indigenous

Unknown

None

Unknown

Unknown

Markets

Domestic

Export


SASRLF = South Australian Southern Rock Lobster Fishery; TRLF = Tasmanian Rock Lobster Fishery; VRLF = Victorian Rock Lobster Fishery; WASCCF = Western Australian South Coast Crustacean Fisheries

a In Victoria, regulations for managing recreational fishing are also applied to fishing activities by Indigenous people. Recognised Traditional Owners (groups that hold native title or have agreements under the Victorian Traditional Owner Settlement Act 2010) are exempt (subject to conditions) from the requirement to hold a recreational fishing licence, and can apply for permits under the Fisheries Act 1995 that authorise customary fishing (for example, different catch and size limits or equipment). The Indigenous category in Table 3 refers to customary fishing undertaken by recognised Traditional Owners. In 2012–13, there were no applications for customary fishing permits to access Southern Rock Lobster.

b Subject to the defence that applies under section 211. of the Native Title Act 1993, 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.


Figure 2: Commercial catch of Southern Rock Lobster in Australian waters, 2001–02 to 2012–13 (fishing seasons)

Figure 2: Commercial catch of Southern Rock Lobster in Australian waters, 2001–02 to 2012–13 (fishing seasons)

Note: Data are based on fishing seasons, which are October 2012 – May 2013 (South Australia), November 2012 – September 2013 (Victoria), November 2012 – September 2013 (Tasmania) and November 2012 – June 2013 (Western Australia south coast).




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 pots11. Sea lion excluder devices are now mandatory in 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 plan12. The fishery management plan responded with a fishery code of practice to prevent and respond to whale entanglements.
  • The biomass of Southern Rock Lobster is being rebuilt off eastern Tasmania to assist in the management of Long-spined Sea Urchins13. These urchins, which have extended their range southwards from New South Wales, can create barren patches of reef through overgrazing. Rebuilding of the Southern Rock Lobster biological stock may reduce barren formation through predation on the urchins.
  • Habitat impacts of gear have been researched and assessed as negligible risk14.

Environmental effects on Southern Rock Lobster
  • The potential impact of climate change on recruitment, growth and mortality has been identified as a risk across the range of the species15.
  • Recruitment, catchability and growth can vary substantially from year to year as a result of environmental changes, including changes in water temperature and movement of oceanic currents16. Below-average recruitment is not necessarily associated with low egg production—it can also result from unusual oceanographic patterns, which can affect larval development and growth.


South Australian Research and Development Institute
b Institute for Marine and Antarctic Studies, University of Tasmania
c Department of Primary Industries, Victoria
d Department of Fisheries, Western Australia