|Scientific Name:||Squatina australis Regan, 1906|
|Taxonomic Source(s):||Regan, C. T. 1906. Descriptions of some new sharks in the British Museum Collection. Annals and Magazine of Natural History (Series 7) 18(108): 435-440.|
|Red List Category & Criteria:||Least Concern ver 3.1|
|Assessor(s):||Walker, T.I., Pogonoski, J. & Pollard, D.A.|
|Reviewer(s):||Simpfendorfer, C., Dulvy, N.K. & Kyne, P.M.|
|Facilitator/Compiler(s):||Kyne, P.M., Walls, R.H.L., Simpfendorfer, C. & Chin, A.|
The Australian Angel Shark (Squatina australis) is a relatively abundant species endemic to the continental shelf (inshore to 130 m) of southern Australia, from the central coast of New South Wales to southern Western Australia, including Tasmania. The Australian Angel Shark is taken as retained byproduct in fisheries targeting higher-valued species, and catch susceptibility is high for demersal trawl gear on the fishing grounds off southeast Australia. However, large areas of its range are not trawled and observer data in the South East Trawl Fishery (Sydney, New South Wales, to Kangaroo Island, South Australia) indicate that abundance of the Australian Angel Shark had not declined during 1994–2004 and, although there was a slight decline during 2005–2006, fishing intensity was subsequently reduced markedly by proactive management action. The species is assessed as Least Concern and its population size is expected to increase in response to management changes.
|Previously published Red List assessments:|
The Australian Angel Shark occurs across southern Australia from the central coast of New South Wales (near Newcastle) (latitude ~32°55’S) to Lancelin in southern Western Australia (latitude ~31°01’S) including Tasmania (Last and Stevens 2009).
Native:Australia (New South Wales, South Australia, Tasmania, Victoria, Western Australia)
|FAO Marine Fishing Areas:|
Indian Ocean – eastern; Pacific – southwest
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||The Australian Angel Shark is common, particularly in the eastern region of its distribution and population size is estimated as relatively large (tens of thousands of mature individuals), although the number and size of subpopulations is unknown. Analyses of data from scientific on-board observer monitoring of commercial trawl catches indicate that for the 11-year period 1994–2004 overall relative abundance (indicated by standardised catch per unit effort) had not declined off southern New South Wales and eastern Victoria, with a slight reduction during the 2-year period 2005–2006 (Walker and Gason 2007).|
|Current Population Trend:||Stable|
|Habitat and Ecology:||The Australian Angel Shark occurs in continental shelf waters to a depth of 130 m and, as a demersal carnivore (Last and Stevens 2009), it inhabits areas of sand and mud substrates, often in seagrass beds or adjacent to rocky reefs (Michael 2001). Males attain ~105 cm total length (TL) and are mature by 90 cm TL; females attain at least 115 cm TL and are mature by 97 cm TL (K. Graham, pers. comm.). Maximum size is reported to be 152 cm TL (Compagno 1984), but specimens >115 cm TL were rare off New South Wales between 1976–1977 and 1996–1997 (Graham 1999). Lecithotrophic viviparous, with litter sizes up to 20, although there is few data on litter size; gives birth in the autumn months (Michael 2001). The gestation period is unknown, but a similar species, the Ornate Angel Shark (S. tergocellata) has a gestation period of 6–12 months and probably reproduces biennially (Bridge et al. 1998). This shark spends its day buried, ingesting prey that move close, but it emerges from the sand or mud at night and actively searches for food (Michael 2001).|
|Use and Trade:||The Australian Angel Shark is caught as byproduct and marketed for its meat.|
|Major Threat(s):||Mean annual catch of the Australia Angel Shark for the period 2000–06 estimated by combining monitoring data from scientific on-board observers and mandatory catch and effort returns submitted by commercial fishing operators was 311 t whole mass of which 97% was retained for marketing and 3% was discarded. The catch was taken off southern New South Wales and eastern Victoria by demersal otter trawl (98%) and Danish seine (2%) in the South East Trawl Sector of the Southern and Eastern Scalefish and Shark Fishery (Walker and Gason 2007). In addition, during this period, small annual catches are reported on mandatory catch and effort returns from commercial fishers using various methods in inshore areas of New South Wales (29–51 t, carcass mass), Victoria (1–5 t, carcass mass), and South Australia (31–38 t, carcass mass) (Walker and Gason 2009). Negligible catches are taken by gillnets and hooks, because of their low catch susceptibility to these fishing methods (Walker et al. 2005, Braccini et al. 2009)|
Two general management measures benefit the conservation of the Australia Angel Shark. Restructuring of the Southern and Eastern Scalefish and Shark Fishery took place during 2006–07 through buy-back of Commonwealth fishing licences (Penney et al. 2014) and implementation of markedly reduced overall fishing effort with progressive reductions in Total Allowable Catches (TACs), particularly in southern New South Wales (Walker and Gason 2007). Implementation of the Management Plan (operational since 1 July 2013) for the South-East Commonwealth Marine Reserves Network (proclaimed in 2007) prohibits demersal otter trawl and Danish seining, and in some areas all other fishing methods, in 14 Commonwealth marine reserves (including one at Macquarie Island outside the range of this species) covering ~388,464 km² over a diverse range of temperate marine environments on the continental shelf, continental slope, and abyssal plain. Stretching from the far south coast of New South Wales, around Tasmania and Victoria, and west to Kangaroo Island off South Australia, the Network provides several refuges over the entire depth range of the Australia Angel Shark (Anonymous 2013). The Management Plan for the South-West Commonwealth Marine Reserves Network (not yet implemented as of February 2016) is similarly expected to provide further refuges for the Australian Angel Shark.
|Citation:||Walker, T.I., Pogonoski, J. & Pollard, D.A. 2016. Squatina australis. The IUCN Red List of Threatened Species 2016: e.T41862A68645631.Downloaded on 20 October 2017.|