|Scientific Name:||Dasyatis zugei|
|Species Authority:||(Müller & Henle, 1841)|
|Red List Category & Criteria:||Near Threatened ver 3.1|
|Reviewer(s):||Kyne, P.M. & Fowler, S.L. (Shark Red List Authority)|
Dasyatis zugei is a small (to 29 cm disc width) inner continental shelf Indo-West Pacific stingray typically found at depths of <100 m. It forms a significant component of the elasmobranch bycatch from fish and prawn trawlers operating within its range (for example, Gulf of Thailand and the Java Sea). This species is also frequently caught off Indian coastal waters in intensive demersal fisheries that occur in that region. There are very high levels of exploitation on the habitat that this species occurs in throughout its range and since it is caught in such large numbers (in all size ranges) by trawlers, it is under a severe level of threat within most of its range. All caught are retained and utilized for typically local human consumption. It appears to have a low fecundity (1 to 3 pups/litter). This species is considered to be close to Vulnerable as a result of past, ongoing and future declines caused by the high level of exploitation in the region, which is only likely to increase in the future.
|Range Description:||Reasonably wide Indo-West Pacific range.|
Native:Bangladesh; Cambodia; China; India; Indonesia; Japan; Malaysia; Myanmar; Philippines; Sri Lanka; Taiwan, Province of China; Thailand; Viet Nam
|FAO Marine Fishing Areas:||
Indian Ocean – eastern; Pacific – northwest; Pacific – western central
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||Nothing known of population structure or size, although taken in large numbers by fisheries in some parts of its range (i.e., Gulf of Thailand and the Java Sea).|
|Habitat and Ecology:||
Dasyatis zugei occurs on the inner continental shelf in depths of typically less than 100 m and usually shallower, over flat, sandy substratum.
Attains maturity at ~19 cm DW (females) and ~18 cm DW (males) and attains maximum sizes of 29 cm DW, but more frequently to 24 cm DW (Last and Compagno 1999, W. White unpublished data). This species is aplacental viviparous, giving birth to 1 to 3 young after an unknown gestation period at a size of approximately 8 to 10 cm DW. In Indonesia this species does not appear to follow an annual reproductive cycle with embryos of varying sizes observed in most months sampled (W. White unpublished data).
Diet not well known but preliminary examination reveals they prey predominantly on small crustaceans (mostly prawns) (W. White unpublished data).
Life history parameters
Age at maturity (years): Unknown.
Size at maturity (disc width): Female: 19.1 cm DW (W. White unpublished data); Male: 17.8 cm DW (W. White unpublished data).
Longevity (years): Unknown.
Maximum size (disc width/total length): 29 cm DW; 75 cm TL (Last and Compagno 1999).
Size at birth: 8 to 10 cm DW (W. White unpublished data).
Average reproductive age (years): Unknown.
Gestation time (months): Unknown.
Reproductive periodicity: Unknown.
Average annual fecundity or litter size: 1 to 3 young/litter (?? Litters/year) (W. White unpublished data) .
Annual rate of population increase: Unknown.
Natural mortality: Unknown.
Dasyatis zugei is a significant component of the elasmobranch bycatch from fish and prawn trawlers operating within its range, for example in the Gulf of Thailand and the Java Sea (Last and Compagno 1999, W. White pers. obs.). This species is also commonly caught off Indian coastal waters in intensive demersal fisheries that occur in that region (Hanfee 1999). There are very high levels of exploitation on the habitat that this species occurs in throughout its range and since it is caught in such large numbers (in all size ranges) by trawlers, it is under a severe level of threat within most of its range.
Typically all are retained and survivability of any discards would presumably be low due to their morphology.
Collection of catch data required across range. Harvest management needed in near future.
The development and implementation of management plans (national and/or regional e.g., under the FAO International Plan of Action for the Conservation and Management of Sharks: IPOA-Sharks) are required to facilitate the conservation and sustainable management of all chondrichthyan species in the region. See Anon. (2004) for an update of progress made by nations in the range of D. zugei.
|Citation:||White, W.T. 2006. Dasyatis zugei. The IUCN Red List of Threatened Species. Version 2014.3. <www.iucnredlist.org>. Downloaded on 26 November 2014.|