|Scientific Name:||Squalus grahami|
|Species Authority:||White, Last & Stevens, 2007|
Squalus sp. subspecies F
|Red List Category & Criteria:||Near Threatened ver 3.1|
|Assessor(s):||Cavanagh, R.D. & Lisney, T.J. (SSG Australia & Oceania Regional Workshop, March 2003)|
|Reviewer(s):||Graham, K. & Fowler, S. (Shark Red List Authority)|
This deepwater dogfish would qualify for Critically Endangered based on application of the criteria to part of its range studied off New South Wales, Australia with documented declines of as much as 97% between 1976 to 1977 and 1996 to 1997. Indeed, almost all trawlable ground on the continental slope off central and southern New South Wales is regularly fished and is likely to be maintaining continual local pressure on this species. However, this area represents less than 20% of its known range, with the rest to the north where fishery threats are non-existent or minor. Thus Squalus grahami is assessed as Near Threatened, reflecting its wider distribution outside the heavily fished area. However, if specimens are found to occur in other areas exploited by fisheries, and if it is found to have the life history characteristics (low fecundity, slow growth and high longevity) typical of better known squalids, the situation must be reevaluated.
|Range Description:||This species was known as Squalus sp. F in Last and Stevens (1994). Known to occur on the slope off Queensland, northeastern Australia, and also captured in trawls on the outer shelf and upper slope along the New South Wales coast.|
Native:Australia (New South Wales, Queensland)
|FAO Marine Fishing Areas:||
Pacific – southwest; Pacific – western central
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||There is currently no information on population or subpopulation size.|
|Habitat and Ecology:||The biology of this dogfish is essentially unknown. It occurs at depths of 120 to 500 m. Maximum total length of males is about 64 cm, and females 73 cm. Size at birth possibly about 22 cm; males mature by about 52 cm, and females about 63 cm. Litter sizes are usually between 3 and 5 pups (K Graham, pers. comm).|
Almost all trawlable ground on the slope off central and southern New South Wales is regularly fished maintaining continual fishing pressure on all species including Squalus grahami. A documented decline of approximately 97% of "greeneye dogsharks" (comprising Squalus mitsukurii and Squalus grahami) between 1976/77 and 1996/97 between the Sydney area (central New South Wales (NSW)) and the Eden-Gabo Island area (southern NSW/northern Victoria) was reported from a fishery independent survey (Graham et al. 2001). Total catches in the abovementioned areas in 220 to 605 m (i.e., much of the known depth range of the two species) declined from a mean of 44.8 kg/h in 1976/77 to a mean of 1.2 kg/h in 1996-97. In 1976/77 the two species were caught in approximately equal numbers off Sydney and Ulladulla, thus it is a fair assumption that the decline was roughly equal for both species in these areas. The 1976/77 Eden data suggested 75% or more of the greeneye dogshark catch in the southern area comprised S. mitsukurii and thus a relatively small proportion of Squalus grahami. However, in 1996 to 1997 no Squalus grahami were caught off Eden-Gabo Island suggesting that trawling to the north may be preventing recruitment of the species into southern NSW.
More than half of the known distribution of this species falls within the area of The Coral Sea Fishery (a Commonwealth managed fishery). This is a very small fishery, with only two operators in the trawl sector with extremely low effort, thus threats to this species from fishing activity in this area are thought to be minimal.
|Conservation Actions:||Currently there are no conservation measures in place for this species.|
|Citation:||Cavanagh, R.D. & Lisney, T.J. (SSG Australia & Oceania Regional Workshop, March 2003) 2003. Squalus grahami. The IUCN Red List of Threatened Species. Version 2015.2. <www.iucnredlist.org>. Downloaded on 31 August 2015.|
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