Table 1: Stock status determination for Eastern Rock Lobster
Jurisdiction |
New South Wales |
Stock |
NSWRLF |
Stock status |
|
Sustainable |
Indicators |
Biomass, CPUE, catch as percentage of TACC, spawning stock abundance (FIS‑based), puerulus recruitment (FIS‑based), size structure |
CPUE = catch per unit effort; FIS = fishery-independent survey; NSWRLF = New South Wales Rock Lobster Fishery; TACC = total allowable commercial catch
Eastern Rock Lobster (Sagmariasus verreauxi)1 occurs on rocky reef and sand/mud substrates in depths of less than 1 metre to about 200 metres, from southern Queensland to Port MacDonnell in South Australia, including around Tasmania. The greatest abundances and the only significant catches occur along the New South Wales coast, where Eastern Rock Lobster is taken by commercial and recreational fishers2,3. The species also occurs off New Zealand, predominantly around the North Island4. Genetic studies have provided preliminary evidence that the stocks off Australia and New Zealand are discrete populations5,6.
The spawning stock of Eastern Rock Lobster is restricted to the north coast of New South Wales. Following spawning and a 9-month larval phase (phyllosoma larvae), pueruli recruit to shallow inshore reefs along the entire New South Wales coast. This suggests a single New South Wales (Australian) biological stock. A current project, using contemporary genetic techniques, is re-examining the connectivity between Australian and New Zealand populations; and among New South Wales, Victorian and Tasmanian components of the Australian population of Eastern Rock Lobster.
Based on existing evidence of stock delineation, status is reported at the level of the single biological stock.
New South Wales Rock Lobster Fishery biological stock
Following concerns about the sustainability of the Eastern Rock Lobster resource in the early 1990s, stock abundance has responded positively to management initiatives, including the introduction of a maximum legal length, individually numbered management tags, share management and a total allowable commercial catch (TACC)2,3,7–9.
The annual TACC has effectively been taken (that is, more than 95 per cent caught) each year since 2004–05, indicating that the TACC has been limiting catch. Catch has increased from 102 tonnes (t) in 2004–05 to 150 t in 2013–14. In the 2012–13 fishing season, 139 t of catch was recorded, marginally below the 2012–13 TACC of 140 t. Catch per unit effort has been increasing since a low point in the early 1990s and is currently the highest observed during the past four decades. A fishery-independent survey in 2012–13 indicated that indices of abundance of spawning stock have been increasing since the late 1990s, and in 2012–13 were the highest observed during the 15-year time series. Based on an annual survey of puerulus abundance along the New South Wales coast, recruitment of pueruli has increased since the mid-1990s against a background of interannual fluctuations2.
A length-structured model of the lobster population and the fishery provides annual estimates of stock biomass and depletion of biomass relative to pre-exploitation levels, and a prospective risk analysis of the likely consequence for biomass of alternative future TACCs. The base-case scenario of the most recent assessment2 estimated that spawning biomass (SB) at the commencement of the 2013–14 season was 34 per cent (90 per cent confidence interval: 24 to 45 per cent) of the unfished (1884–85) level, having increased fourfold (median SB2013–14/SB1994–95 = 4.12; 90 per cent confidence interval: 3.28 to 5.11) since 1994–95. The stock is not considered to be recruitment overfished.
Based on the prospective risk analysis of the consequences of alternative future catches, an independent Total Allowable Catch Committee9 sets TACCs annually to maintain the spawning biomass above the biological reference point of 25 per cent of unfished biomass. The current level of fishing pressure is 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: Eastern Rock Lobster biology3,10, 11
Longevity and maximum size |
30+ years; 260 mm CL |
Maturity (50%) |
Females: 167 mm CL |
CL = carapace length
Figure 1: Distribution of reported commercial catch of Eastern Rock Lobster in Australian waters, 2012–13 (fishing season)
Table 3: Main features and statistics for Eastern Rock Lobster fisheries in Australia, 2012–13 (fishing season)
Jurisdiction |
New South Wales |
Fishing methods |
Commercial |
Lobster trap/pot |
✓ |
Diving (free-diving) |
✓ |
Recreational |
Lobster trap/pot |
✓ |
Diving (free-diving) |
✓ |
Indigenous |
Lobster trap/pot |
✓ |
Diving (free-diving) |
✓ |
Management methods |
Commercial |
Limited entry |
✓ |
Size limits |
✓ |
Vessel restrictions |
✓ |
Gear restrictions |
✓ |
Total allowable catch |
✓ |
Spatial closures |
✓ |
Management tags |
✓ |
Demerit points, share confiscation |
✓ |
Recreational |
Gear restrictions |
✓ |
Bag limits |
✓ |
Size limits |
✓ |
Spatial closures |
✓ |
Indigenousa,b |
Gear restrictions |
✓ |
Bag limits |
✓ |
Size limits |
✓ |
Spatial closures |
✓ |
Aboriginal cultural fishing authority |
✓ |
Active vessels |
|
82 in NSWRLFc |
Catch |
Commercial |
139 t in NSWRLF |
Recreational |
Unknown |
Indigenous |
Unknown |
Markets |
Domestic |
✓ |
Export |
✓ |
NSWRLF = New South Wales Rock Lobster Fishery
a The Aboriginal Fishing Interim Compliance Policy allows an Indigenous fisher in New South Wales to take in excess of a recreational bag limit in certain circumstances—for example, if they are doing so to provide fish to other community members who cannot harvest themselves.
b The Aboriginal cultural fishing authority is the authority that Indigenous persons can apply to to take catches outside the recreational limits under the New South Wales Fisheries Management Act 1994, section 37(1)(c1) (Aboriginal cultural fishing authority).
c Eighty-two fishing businesses reported catches during the 2012–13 fishing season.
Figure 2: Commercial catch of Eastern Rock Lobster in Australian waters, 1950–51 to 2012–13
Note: Data are for financial years before 2011–12, the 13-month July–July fishing year for 2011–12, and the August–July fishing year for 2012–13.
- Bycatch from the commercial fishery is minimal (based on data from observer surveys), and fishing with traps is likely to result in minimal physical disturbance to benthic habitats relative to the impacts of sea and swell in a high-energy coastal environment.
- Loss of traps in the deepwater component of the fishery, associated with loss of headgear, results in some ghost-fishing mortality of Rock Lobsters. This unproductive mortality is the subject of current research, and is being mitigated through the adoption of sacrificial panels in traps and acoustic release technology to provide ‘at call’ access to submerged headgear12.
- Physical impacts of fish and prawn trawling on benthic habitat inhabited by lobsters (in particular, low-relief reefs on the mid-continental shelf) may have negative effects on the lobster population and subsequent catches at affected locations.
- Changes in water temperature, and the spatial and temporal behaviour of the East Australian Current, due to climate change, may potentially affect the distribution of spawning stock, larval dispersal, and the strength and distribution of recruitment of peuruli. This would influence the distribution and abundance of juvenile lobsters recruiting to the fishable stock, and subsequently spatial and temporal patterns of catch in the fishery.
a Department of Primary Industries, New South Wales