Justification
Sagmariasus verreauxi has been assessed as Least Concern. This species has a broad geographic range and is found in high abundance. Although this species is commercially harvested, catch per unit effort data indicates no major declines at the present time. There are a number of management plans in place for this species.
Geographic Range Information
This species is known from eastern Australia and New Zealand, including the Chatham and Kermadec Islands (Holthuis 2002). Specifically, it is known from Tweed Heads, New South Wales to Tasmania (Montgomery and Craig 2005). It is mainly found in the north of the North Island, New Zealand (Ministry of Fisheries Science Group 2008). In Australia, it is more abundant at higher latitudes (above 34 degrees), compared to the southern part of its distribution (Montgomery and Craig 2005).
Population Information
This is a common species, and is commercially harvested in both Australia and New Zealand (Montgomery et al. 2009).
Australia
In Australia this species is part of a managed fishery, where there are 131 shareholders which are bound by a total allowable commercial catch (TACC) (Montgomery et al. 2009). This is set by the New South Wales Fisheries Management Act 1994 and is divided between the shareholders (Montgomery et al. 2009). In 2007-2008 this was set at 124 tonnes, bringing in a revenue of around $5 million Australian dollars (Liggins et al. 2008, in Montgomery et al. 2009). This species is usually caught in a baited trap, although a small proportion can be taken by hand (Montgomery et al. 2009).
The data for this species have shown that landings have been fairly consistent over the past thirty years (FishStat 2000). However, CPUE has declined between 1969-1970 and 1991-1992 for New South Wales stock:
CPUE (kg per fisher trap month) data:
1969-1970: 13, 1970-1971: 9.5, 1971-1972: 18, 1972-1973: 9.5, 1973-1974: 9, 1974-1975: 13, 1975-1976: 7, 1976-1977: 8 1977-1978: 7, 1978-1979: 7, 1979-1980: 5, 1980-1981: 4, 1981-1982: 5, 1982-1983: 4, 1983-1984: 4, 1984-1985: 4, 1985-1986: 4, 1986-1987: 4, 1987-1988: 4, 1988-1989: 4, 1989-1990: 3, 1990-1991: 3, 1991-1992: 3 (Montgomery 1993).
The landings (which do not account for increase in effort or restrictions in quotas) are given below (tonnes): Australia (Fishstat 2000).
1978: 93
1979: 68
1980: 108
1981: 99
1982: 144
1983: 155
1984: 158 1985: 167
1986: 150
1987: 200
1988: 210
1989: 79
1990: 87
1991: 86
1992: 98
1993: 100
1994: 143
1995: 151
1996: 97
1997: 104
1998: 108
1999: 110
2000: 117
2001: 103
2002: 103
2003: 122
2004: 108
2005: 99
2006: 101
2007: 110
New Zealand
In New Zealand, this species is also taken during recreational fishing, for customs by Maori and also illegally, for which there are no precise data (Ministry of Fisheries Science (Comps.) 2008). The status of the stock of this species is unknown (Ministry of Fisheries Science (Comps.) 2008).
As this species is harvested along with Jasus edwardsii under the name of 'rock lobster', it is often difficult to obtain data for this species alone (Ministry of Fisheries Science Group (Comps.) 2008).
The landings (which do not account for increase in effort or restrictions in quotas) are given below (tonnes):
Year: New Zealand (Fishstat 2000)
1978: 40
1979: 40
1980: 40
1981: 40
1982: 40
1983: 40
1984: 32
1985: 14
1986: 8
1987: 0.5
1988: 0.5
1989: 0.5
1990: 2
1991: 21
1992: 15
1993: 8
1994: 5
1995: 8
1996: 64
1997: 54
1998: 16
1999: 13
2000: 35
2001: 10
2002: 8
2003: 16
2004: 19
2005: 19
2006: 29
2007: 29
Habitat and Ecology Information
This species usually occurs between 0-155 m (Holthuis 1991). Juveniles settle on rocky reefs upon maturation while sub-adults migrate to the northern tip of the northern Island where they settle and breed. Adults commonly occur on low-lying reefs. They are found on sand, gravel and rocks (Holthuis 2002). This species is known to migrate, from higher to lower latitudes for spawning (Montgomery et al. 2009). There appears to be a seasonal migration between continental shelves during winter months to shallow near-shore reef environments during summer (Montgomery et al. 2009).
The Australian population is genetically different to the New Zealand population (Montgomery and Craig 2005).
Threats Information
Commercial exploitation of this species does not pose a significant threat to the population numbers at the present time. There are no other known major threats to this species.
Use and Trade Information
This species is commercially harvested for food. Holthuis (1991) notes that fishing is greatest in the northern parts of this species range; however landings data for both areas are misleading as they are often aggregates of other species in the same genus/sub-genus.
Conservation Actions Information
There are some specific conservation measures in place for this species. In Australia, Queensland fisheries have imposed a minimum size restriction (carapace width of 104 mm) for this species (Sumpton et al. 2004). There is a tagging system in place in New Zealand which is designed to reduce illegal harvesting (Yandle 2006). Additionally the 'National Rock Lobster Management Group' created in 1992, and the Rock Lobster Steering Committee have developed a harvest strategy to manage stock levels, which has incorporated traditional Maori cultural concerns (Yandle 2006). A research programme is also in place in New Zealand (Yandle 2006). Various minimum legal tail sizes depending on the location and whether for commercial or recreational purposes are imposed (New Zealand Government 2008). In Australia for commercial and recreational fisheries, the standard carapace lengths are between 104 mm and 180 mm (Montgomery et al. 2009). This species can also be found in a number of Marine Protected Areas (Freeman 2008).
