|Scientific Name:||Himantura signifer|
|Species Authority:||Compagno & Roberts, 1982|
|Red List Category & Criteria:||Endangered B1ab(iii) ver 3.1|
|Reviewer(s):||Musick, J.A. & Fowler, S.L. (Shark Red List Authority)|
This assessment is based on the information published in the 2005 shark status survey (Fowler et al. 2005).
The White-edge Freshwater Whipray (Himantura signifer) is a very rare freshwater ray known from only a few specimens and four riverine systems (although it may also be present but unrecorded in other rivers). It is confined to tropical freshwater habitats that are under intensive threat from fisheries, pollution, logging in the catchment areas and river engineering projects.
|Range Description:||This is a freshwater species, occurring in the rivers of Southeast Asia. It is known from the Kapuas River in western Kalimantan and Indragiri River, Sumatra, Indonesia; Perak River, western Peninsular Malaysia; and Chao Phrya River, Thailand (Taniuchi 1979, Compagno and Roberts 1982).
Subpopulation details are unknown. If, as seems likely, this ray is unable to transit marine habitats, each riverine population will be completely isolated.
Native:Indonesia; Malaysia; Thailand
|Range Map:||Click here to open the map viewer and explore range.|
|Habitat and Ecology:||This rarely recorded freshwater species is known from about 10 specimens in museum collections, mostly from the Kapuas River, Kalimantan. No information is available on any of this species' life history parameters.|
|Use and Trade:||aquarium use|
|Major Threat(s):||This rare ray is taken infrequently as bycatch in freshwater teleost fisheries, which are intensive through much of its range. It is possibly taken for the aquarium trade (unverified). It lives in areas where riverine pollution and habitat degradation are continuing apace. Populations (which are probably isolated in each river where it occurs) are likely to be under serious continued threat as a result of logging activities and pollution from agricultural chemicals, sewage and industrial waste in the river catchments and loss of habitat due to dam construction (e.g., Chao Phraya River). Habitat loss and degradation are likely a major impact on the species.|
|Conservation Actions:||The Thai government started a project in the 1990s to breed this and other freshwater stingrays in captivity at Chai Nat above the dam on the Chao Phraya River to counter declines of freshwater rays in the river. Two specimens of what was possibly this species (or a closely related species) were seen in captivity here in 1993. We later (1996) learned that the project had been put on hold, at least temporarily.|
|Citation:||Compagno, L.J.V. 2005. Himantura signifer. The IUCN Red List of Threatened Species. Version 2015.2. <www.iucnredlist.org>. Downloaded on 29 August 2015.|