Squatina tergocellata

Taxonomy

Assessment Information

Geographic Range

Population

Habitat and Ecology

Threats

Conservation Actions

View Printer Friendly

Taxonomy [top]

Kingdom	Phylum	Class	Order	Family
ANIMALIA	CHORDATA	CHONDRICHTHYES	SQUATINIFORMES	SQUATINIDAE

Scientific Name:

Squatina tergocellata

Species Authority:

McCulloch, 1914

Common Name/s:

English

–

Archbishop, Ornate Angel Shark

Assessment Information [top]

Red List Category & Criteria:	Least Concern ver 3.1
Year Published:	2003
Assessor/s:	Kyne, P.M. & Bennett, M.B. (SSG Australia & Oceania Regional Workshop, March 2003)
Reviewer/s:	Fowler, S. & Cavanagh, R.D. (Shark Red List Authority)
Justification: Squatina tergocellata is endemic to southern Australia, demersal on the continental shelf and upper slope in depths of 130 to 400 m (most common about 300 m). The species matures at a large size (relative to maximum size), produces litters of two to nine young (average 4.5) probably biennially, after a gestation period of 6 to 12 months. It is taken in the Great Australian Bight Trawl Fishery (shelf/upper slope component) where catches appear to be stable. This component of the fishery operates mostly in 120 to 180 m, therefore a large portion of the species depth range is not trawled. Furthermore, the fishery receives relatively low effort (the fishery is managed by limited entry with only 10 Statuary Fishing Rights) and a large portion of the species range receives minimal fishing effort. The species is assessed as Least Concern. However, given documented declines in other angel shark species together with their ?slow? life history characteristics, any future expansion of fisheries within its area of occurrence would need to closely monitor catches of this species.

Geographic Range [top]

Range Description:	Endemic to southern Australia from off Geraldton, Western Australia to off Port Lincoln, South Australia.
Countries:	Native: Australia (South Australia, Western Australia)
FAO Marine Fishing Areas:	Native: Indian Ocean – eastern
Range Map:	Click here to open the map viewer and explore range.

Population [top]

Population:	No available information on subpopulations or population sizes.
Population Trend:	Stable

Habitat and Ecology [top]

Habitat and Ecology:	Squatina tergocellata is demersal on the continental shelf and upper slope in 130 to 400 m, but most common in about 300 m (Last and Stevens 1994). The species may display spatial segregation of age classes, with older age classes more common in deeper waters (Bridge et al. 1998). Maximum size of females 140 cm total length (TL); of males 103 cm TL (Bridge et al. 1998). Male reach sexual maturity at 81 to 91 cm TL and females at 115 to 125 cm TL. Gravid females with near-term embryos were observed during January and February. Fecundity ranges from 2 to 9 (mean = 4.5). Minimum gestation period of 6 to 12 months with parturition probably occurring biennially. Diet is dominated by squid (Notodarus gouldi) and fish (monacanthids) (Bridge et al. 1998). Information on age and growth is not available.
Systems:	Marine

Habitat and Ecology:

Squatina tergocellata is demersal on the continental shelf and upper slope in 130 to 400 m, but most common in about 300 m (Last and Stevens 1994). The species may display spatial segregation of age classes, with older age classes more common in deeper waters (Bridge et al. 1998). Maximum size of females 140 cm total length (TL); of males 103 cm TL (Bridge et al. 1998). Male reach sexual maturity at 81 to 91 cm TL and females at 115 to 125 cm TL. Gravid females with near-term embryos were observed during January and February. Fecundity ranges from 2 to 9 (mean = 4.5). Minimum gestation period of 6 to 12 months with parturition probably occurring biennially. Diet is dominated by squid (Notodarus gouldi) and fish (monacanthids) (Bridge et al. 1998). Information on age and growth is not available.

Systems:

Marine

Threats [top]

Major Threat(s):	Squatina tergocellata is commonly taken and marketed in the Australian Commonwealth managed Great Australian Bight Trawl Fishery (GABTF). The species is taken in the shelf/upper slope component of the fishery which fishes mostly in 120 to 180 m and therefore, only a portion of the species bathymetric range is fished (furthermore, as the species is most common in about 300 m most of the population would not be impacted by fishing). Additionally, the fishery receives relatively low effort (the fishery is managed by limited entry with only 10 Statuary Fishing Rights) and a large portion of the species range, particularly in the west, receives minimal fishing effort (Caton 2002). The fishery mostly takes immature individuals (Bridge et al. 1998). Reported landings from this fishery are as follows: 1988-1992 (five year period), 234 tonnes; 1995, 97 tonnes; 1996, 95 tonnes; 1997, 140 tonnes; 1999, 109 tonnes; 2000, 69 tonnes; 2001, 88 tonnes; and, 2002, 84 tonnes (McLoughlin et al. 1994, McLoughlin et al. 1995, McLoughlin et al. 1997, Caton et al. 1997, Caton et al. 1999, Caton 2002, Phil Sahlqvist pers. comm.). The decline in catch in 2000 corresponds with a decrease in fishing effort. Overall, the stock appears stable in the Great Australian Bight. Furthermore, while catches were variable, no trend has been observed in catch rates of S. tergocellata in the South East Trawl Fishery Observer Program (sampling at the eastern extent of the species range) over the ten-year period, 1992 to 2002 (T. Walker, pers. comm). Given the apparent ?slow? life history of angel sharks together with documented declines of other species (Holts 1988, Graham et al. 2001) any future increase in fishing effort in the area of occurrence of Squatina tergocellata should be monitored to ensure the species is not adversely affected.

Major Threat(s):

Squatina tergocellata is commonly taken and marketed in the Australian Commonwealth managed Great Australian Bight Trawl Fishery (GABTF). The species is taken in the shelf/upper slope component of the fishery which fishes mostly in 120 to 180 m and therefore, only a portion of the species bathymetric range is fished (furthermore, as the species is most common in about 300 m most of the population would not be impacted by fishing). Additionally, the fishery receives relatively low effort (the fishery is managed by limited entry with only 10 Statuary Fishing Rights) and a large portion of the species range, particularly in the west, receives minimal fishing effort (Caton 2002). The fishery mostly takes immature individuals (Bridge et al. 1998). Reported landings from this fishery are as follows: 1988-1992 (five year period), 234 tonnes; 1995, 97 tonnes; 1996, 95 tonnes; 1997, 140 tonnes; 1999, 109 tonnes; 2000, 69 tonnes; 2001, 88 tonnes; and, 2002, 84 tonnes (McLoughlin et al. 1994, McLoughlin et al. 1995, McLoughlin et al. 1997, Caton et al. 1997, Caton et al. 1999, Caton 2002, Phil Sahlqvist pers. comm.). The decline in catch in 2000 corresponds with a decrease in fishing effort. Overall, the stock appears stable in the Great Australian Bight. Furthermore, while catches were variable, no trend has been observed in catch rates of S. tergocellata in the South East Trawl Fishery Observer Program (sampling at the eastern extent of the species range) over the ten-year period, 1992 to 2002 (T. Walker, pers. comm).

Given the apparent ?slow? life history of angel sharks together with documented declines of other species (Holts 1988, Graham et al. 2001) any future increase in fishing effort in the area of occurrence of Squatina tergocellata should be monitored to ensure the species is not adversely affected.

Conservation Actions [top]

Conservation Actions:	There are currently no quotas in place for catches of the species in the GABTF. The species is likely to occur in the Commonwealth managed Great Australian Bight Marine Park Benthic Protection Area, a 20 nm strip extending out from the coast to 200 nm offshore where demersal trawling is prohibited.

Conservation Actions:

There are currently no quotas in place for catches of the species in the GABTF. The species is likely to occur in the Commonwealth managed Great Australian Bight Marine Park Benthic Protection Area, a 20 nm strip extending out from the coast to 200 nm offshore where demersal trawling is prohibited.

Citation:	Kyne, P.M. & Bennett, M.B. 2003. Squatina tergocellata. In: IUCN 2011. IUCN Red List of Threatened Species. Version 2011.2. <www.iucnredlist.org>. Downloaded on 22 May 2012.
Disclaimer:	To make use of this information, please check the <Terms of Use>.
Feedback:	If you see any errors or have any questions or suggestions on what is shown on this page, please fill in the feedback form so that we can correct or extend the information provided