|Scientific Name:||Trygonoptera personata|
|Species Authority:||Last & Gomon, 1987|
|Red List Category & Criteria:||Least Concern ver 3.1|
|Reviewer(s):||Kyne, P.M., Fowler, S.L. & Compagno, L.J.V. (Shark Red List Authority)|
A small Eastern Indian endemic stingaree from southwestern Australia (the state of Western Australia) which is relatively common in shallow water over sand and seagrass to 70 m depth. Although Trygonoptera personata forms a considerable component of the biomass of bycatch in the scallop and prawn trawl fisheries that operate off Perth and Mandurah, this species is of no commercial value and those caught by trawlers are typically returned alive. Only a small number of trawlers operate in this fishery, and while some small-scale trawl operations exist in the northern part of the species range (i.e., Abrolhos Islands and Shark Bay) which may potentially take the species as bycatch, the overall trawl fishing pressure across the species' range is low. Given the low fecundity of the species (1 to 2 young per year), the high abortion rates among pregnant females landed by trawlers is the only real threat to this species and the catches of this species as bycatch should be monitored into the future (particularly given the species' relatively narrow geographical range).
|Range Description:||Endemic to the Eastern Indian off Western Australia: found off the lower west coast of Western Australia from Geographe Bay (34°10'S) north to Shark Bay (25°S) (Last and Stevens 1994, Hyndes et al. 1999).|
Native:Australia (Western Australia)
|FAO Marine Fishing Areas:|
Indian Ocean – eastern
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||Relatively common over scallop and prawn trawl grounds on the upper continental shelf off the central and lower west coast of Australia. Appears to be more common in the southern part of its range.|
|Current Population Trend:||Stable|
|Habitat and Ecology:||Trygonoptera personata is a relatively common species found over sand and seagrass habitats on the upper continental shelf in depths to 70 m (Last and Stevens 1994). Aplacental viviparous species with ovulation and conception occurring in July and parturition occurring 10 months later, i.e., April/May (White et al. 2002). Litter size ranges from one to two and females reproduce each year. Females and males are mature at 23 and 22 cm DW, respectively, and attain maximum sizes of 31 and 27 cm DW, respectively (White et al. 2002). Females and males are mature by the end of their fourth year of life and reach maximum ages of 16 and 10 years, respectively (White et al. 2002). Von Bertalanffy growth parameters for both sexes were: DWinf = 30.3 cm (F) and 26.9 cm (M), t0 = -3.9 (F) and -3.1 (M) years, k = 0.14 (F) and 0.20 (M). Diet consists primarily of polychaetes (errant and sedentary) and crustaceans (Platell et al. 1998).
Life history parameters (from White et al. 2002)
Age at maturity: 4 years (both male and female).
Size at maturity (disc width): 23 cm DW (female); 22 cm DW (male).
Longevity: 16 years (females); 10 years (males).
Maximum size (disc width): 31 cm DW (females); 27 cm DW (males).
Size at birth: 12.8 cm DW.
Average reproductive age (years): Unknown.
Gestation time: 10 months.
Reproductive periodicity: 1 litter per annum.
Average annual fecundity or litter size: 1 to 2 young per annum.
Annual rate of population increase: Unknown.
Natural mortality: Unknown
Trygonoptera personata forms a considerable component of the biomass of bycatch in the scallop and prawn trawl fisheries that operate off Perth and Mandurah. A trawl survey of demersal fishes on the coastal shelf regions of southwestern Australia in the early 1990s reported that T. personata constituted 2.6% of the total biomass of fish caught (Laurenson et al. 1994, Hyndes et al. 1999).
Only a small number of trawlers operate in the scallop and prawn trawl fisheries that operate off Perth and Mandurah, and while some small-scale trawl operations exist in the northern part of the species range (i.e., Abrolhos Islands and Shark Bay) which may potentially take the species as bycatch, the overall trawl fishing pressure across the species' range is low.
This species is of no commercial value and all those caught by trawlers are typically returned alive. The only real concern for this species and other urolophids is that a large percentage of pregnant females landed abort their young before they are returned (White et al. 2001). Since the fecundity of this species is so low (one to two) and gestation is relatively long (10 months), any additional fishing pressure could have a significant effect on populations of this species.
This species is generally not caught by recreational fisherman. There are no real threats from pollution within the range of this species.
None in place. Monitoring of this species and other elasmobranchs caught as bycatch off the central and lower west coast of Australia should be conducted to establish whether the population sizes are stable or declining. A follow-up trawl survey, identical to that conducted in the early 1990s, on the lower west coast of Australia should be conducted to determine any trends in population sizes of such species.
The effective implementation of the Australian National Plan of Action for the Conservation and Management of Sharks (Shark Advisory Group and Lack 2004) (under the FAO International Plan of Action for the Conservation and Management of Sharks: IPOA-Sharks) will help to facilitate the conservation and sustainable management of all chondrichthyan species in Australia.
|Citation:||White, W.T. 2006. Trygonoptera personata. The IUCN Red List of Threatened Species 2006: e.T60084A12234687.Downloaded on 31 July 2016.|