Table 1: Stock status determination for Tropical Rock Lobster
Jurisdiction |
Commonwealth, Torres Strait Protected Zone Joint Authority, Queensland |
Northern Territory |
Western Australia |
Stock |
North-eastern Australian (CRF, CSF, TSTRLF) |
Northern Territory |
Western Australia |
Stock status |
|
Negligiblea |
Negligibleb |
Sustainable |
|
|
Indicators |
Biomass, fishing mortality |
|
|
CRF = Crayfish and Rock Lobster Fishery (Queensland); CSF = Coral Sea Fishery (Commonwealth); TSTRLF = Torres Strait Tropical Rock Lobster Fishery (Commonwealth)
a 'Negligible' means historically low catch; no stock status. No commercial catch is taken from the Northern Territory. It has been estimated that around 300 kg is taken each year by recreational fisheries.
b 'Negligible' means historically low catch; no stock status. No commercial catch is taken from Western Australia. It has been estimated that 198 ± 98 individuals were taken by boat-based recreational fishing in 2011–12.
Tropical Rock Lobster populations in northern Queensland (managed by Queensland), the Coral Sea (managed by the Commonwealth) and the Torres Strait (managed by the Torres Strait Protected Zone Joint Authority) are thought to comprise a single north-eastern Australian biological stock, as a result of mixing of larvae in the Coral Sea1. Stock assessments have not been carried out for the complete biological stock, but have been conducted on the various parts of it. Stock status in this chapter is reported at the level of the single north-eastern Australian biological stock.
Although Tropical Rock Lobster is also present in both the Northern Territory and northern Western Australia, biological stock structures in these regions have not been studied.
North-eastern Australian biological stock
Stock status for the entire Tropical Rock Lobster biological stock has been established using evidence from the Torres Strait, Queensland and Coral Sea parts of the biological stock.
For the Torres Strait part of the biological stock, the most recent assessment2 estimated that spawning stock biomass in 2013 was 114 per cent of the unfished (1973) level. This part of the stock is not considered to be recruitment overfished3. The model-generated nominal total allowable catch (TAC) for 2013 was 871 tonnes (t), and 586 t was caught. Therefore, the level of fishing mortality is unlikely to cause this part of the stock to become recruitment overfished3.
For the Queensland part of the biological stock, the most recent stock assessment4 estimated that biomass at the start of 2008 was 60–70 per cent of the unfished (1988) level. A TAC of 195 t was introduced for the commercial fishery in 2009. The TAC was based on a conservative 80 per cent of the estimated maximum sustainable yield for the Queensland portion of the stock. The commercial catch since 2009 has been below the TAC5,6. Catch rates in 2013 were within historical limits and have shown a rising trend since 20096. As a result, this part of the biological stock is not considered to be recruitment overfished7, and current fishing mortality is unlikely to cause this part of the biological stock to become recruitment overfished7.
No quantitative stock assessments have been carried out for the Coral Sea part of the biological stock, but there is only limited targeting of Tropical Rock Lobster in this area. Estimates of density on Coral Sea reefs, inferred from fishers’ catch rates, suggest that lobster abundance is likely to be many times higher than would be required to support the total historical catch (less than 10 t)8. This part of the biological stock is not considered to be recruitment overfished. Additionally, no commercial catch was recorded in 2013. Therefore, fishing mortality is unlikely to cause this part of the biological stock to become recruitment overfished.
On the basis of the evidence provided above, the entire biological stock is classified as a sustainable stock.
Table 2: Tropical Rocklobster biology9–11
Longevity and maximum size |
3–5+ years; >150 mm CL |
Maturity (50%) |
2–3 years; ~100 mm CL |
CL = carapace length
Figure 1: Distribution of reported commercial catch of Tropical Rock Lobster in Australian waters, 2013 (calendar year)
Table 3: Main features and statistics for Tropical Rock Lobster fisheries in Australia, 2013 (calendar year)
Jurisdiction |
Torres Strait Protected Zone Joint Authority |
Queensland |
Commonwealth |
Fishing methods |
Commercial |
Diving |
✓ |
✓ |
✓ |
Recreationala |
Diving |
|
✓ |
|
Indigenousb,c |
Diving |
✓ |
✓ |
|
Management methods |
Commercial |
Limited entry |
✓ (non-Indigenous) |
✓ |
✓ |
Size limits |
✓ |
✓ |
✓ |
Vessel restrictions |
|
✓ |
✓ |
Gear restrictions |
✓ |
✓ |
✓ |
Total allowable catch |
✓ (nonbinding) |
✓ |
✓ |
Spatial closures |
|
✓ |
✓ |
Seasonal closures |
✓ |
✓ |
|
Prohibition on take of egg-bearing and tar-spot females |
|
✓ |
|
Recreationala |
Possession limits |
|
✓ |
|
Size limits |
|
✓ |
|
Gear restrictions |
|
✓ |
|
Seasonal closures |
|
✓ |
|
Spatial closures |
|
✓ |
|
Prohibition on take of egg-bearing and tar-spot females |
|
✓ |
|
Indigenousb–d |
Bag limits |
✓ |
|
|
Gear restrictions |
|
✓ |
|
Active vessels |
|
In TSTRLF:
11 non-Indigenous commercial
215 Indigenous commercial
1 cross-endorsed PNG commercial vessel. |
7 in CRF |
0 in CSF |
Catch |
Commercial |
586 t in TSTRLF |
181 t in CRF |
0 t in CSF |
Recreationala |
Unknown |
Unknown (minor) |
|
Indigenousb,c |
Unknown |
13 000 lobsters (in 2001) |
|
Markets |
Domestic |
✓ |
✓ |
|
Export |
✓ |
✓ |
|
CRF = Crayfish and Rock Lobster Fishery (Queensland); CSF = Coral Sea Fishery (Commonwealth); PNG = Papua New Guinea; TSTRLF = Torres Strait Tropical Rock Lobster Fishery (Commonwealth)
a The Australian Government does not manage recreational fishing in Commonwealth waters. Recreational fishing in Commonwealth waters is managed by the state or territory immediately adjacent to those waters, under its management regulations.
b The Australian Government does not manage noncommercial Indigenous fishing in Commonwealth waters, with the exception of the Torres Strait. In general, noncommercial Indigenous fishing in Commonwealth waters is managed by the state or territory immediately adjacent to those waters. In the Torres Strait, both commercial and noncommercial Indigenous fishing is managed by the Torres Strait Protected Zone Joint Authority (PZJA) through the Australian Fisheries Management Authority (Commonwealth); the Department of Agriculture, Fisheries and Forestry (Queensland); and the Torres Strait Regional Authority. The PZJA also manages non-Indigenous commercial fishing in the Torres Strait.
c In Queensland, under the Fisheries Act 1994 (Qld), Indigenous fishers in Queensland are able to use prescribed traditional and noncommercial fishing apparatus in waters open to fishing. Size and possession limits, and seasonal closures do not apply to Indigenous fishers. Further exemptions to fishery regulations may be applied for through permits.
d This specifically refers to noncommercial Indigenous catch. Commercial Indigenous catch in the Torres Strait is included under ‘commercial’.
Figure 2: Commercial catch of Tropical Rock Lobster in Australian waters, 2001 to 2013 (calendar years)
- Fishing for Tropical Rock Lobster has little direct impact on the marine environment or other fish species, since hand-collection fishing methods allow careful selection of catch8.
- The abundance of Tropical Rock Lobster is highly influenced by environmental conditions, which affect settlement and recruitment. Ocean current and wind patterns affect transport of larvae and create variability in abundance. These variations should be taken into account in setting TACs1,10.
a Australian Bureau of Agricultural and Resource Economics and Sciences
b Department of Agriculture, Fisheries and Forestry, Queensland