|Scientific Name:||Glyphis gangeticus|
|Species Authority:||(Müller & Henle, 1839)|
|Taxonomic Notes:||Carcharhinus murrayi (Gunther 1887) is a possible junior synonym of this species. This is uncertain however, as the holotype and only known specimen has been misplaced. Also, most literature records and specimens labeled as this species are in fact bull sharks Carcharhinus leucas or other Carcharhinid species. However, after an extensive 10-year search, a few specimens were caught in 1996 in the Ganges River (Compagno 2002).|
|Red List Category & Criteria:||Critically Endangered A2cde; C2b ver 3.1|
|Reviewer(s):||Valenti, S.V. & Gibson, C.G. (Shark Red List Authority)|
The elusive Ganges shark is a freshwater riverine and possibly inshore marine and estuarine shark. Originally known only from three museum specimens, collected in the 19th century from fresh water in the lower reaches of the Ganges-Hooghly river system. It has been and is currently being fished in the Ganges-Hooghli river system, although the details are little known. Other probable threats include overfishing, habitat degradation from pollution, increasing river utilization and management, including construction of dams and barrages (Compagno 1997). This species was originally assessed as Critically Endangered on the 1996 Red List. It appears to be restricted to a very narrow band of habitat that is heavily impacted by human activity, and in the absence of a conclusive published study to show that the situation has changed, this assessment remains Critically Endangered.
|Previously published Red List assessments:|
|Range Description:||This species is known only from the lower reaches of the Ganges-Hooghli river system, West Bengal, India. It possibly occurs in other river systems in the area. Could also occur in shallow marine estuaries although there are no verified marine records of this species to date. |
Traditionally, this species has been assigned a wide range in the Indo-West Pacific, but this was found to be mostly based on other species of requiem sharks, particularly members of the genus Carcharhinus (Compagno 2005).
|FAO Marine Fishing Areas:|
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||Originally known only from three museum specimens (one each in the Museum National d'Histoire Naturelle, Paris, Humboldt Museum, Berlin and Zoological Survey of India, Calcutta), all of which were collected in the nineteenth century. There were no records between 1867 until 1996, although 1996 records have not been confirmed as Glyphis gangeticus. A specimen collected 84 km upstream of the mouth of the Hooghli River, at Mahishadal in 2001 has been identified as Glyphis gangeticus but on photographs of the jaw only (Compagno in prep).|
|Current Population Trend:||Decreasing|
|Habitat and Ecology:||This is a little known species that is yet to be adequately described (Martin 2005). Size at maturity is estimated at about 178 cm TL (Compagno 2005), maximum size at about 204 cm TL and size at birth at 56 to 61 cm TL (Compagno 2005). The habitat of this species is thought to be fresh water in the lower reaches of the Ganges-Hooghly River system, possibly also shallow marine estuaries but there are no verified marine records of this species. The small eyes and slender teeth of this shark suggest that it is primarily a fish-eater and is adapted to turbid water such as occurs in the Ganges River and the Bay of Bengal (Compagno 1997). The eyes of G. gangeticus are tilted dorsally rather than laterally or ventrally, as in most carcharhinids, suggesting that this species may swim along the bottom and scan the water above it for potential prey back-lit by the sun (Compagno 1984). However, Roberts (2005) reports that G. gangeticus in the Bay of Bengal feed heavily on dasyatid stingrays, which spend much of their time on the bottom. Glyphis gangeticus is probably viviparous (Compagno et al. 2005). It has been nominally implicated in numerous attacks on humans in the Ganges but since C. leucas occurs in the same river system this cannot be proven at present and it is possible that C. leucas was involved in most of, if not all, of the attacks (Compagno in prep).|
|Major Threat(s):||Historically, and is currently fished in the Ganges-Hooghly river system, although the details are not well known (Compagno 2005). It is caught by gillnet and appears in the international trade in shark jaws as curios (M. Harris pers. comm.), and probably also in the oriental fin trade and is consumed locally for its meat (Compagno 2005). There are major fisheries for sharks in India and large inshore carcharhinids, including Glyphis species, are readily targeted (L.J.V. Compagno pers. obs). Other probable threats include overfishing, habitat degradation from pollution, increasing river utilization and management, including construction of dams and barrages (Compagno 1997). A few jaws of what is apparently this species have been observed in international trade during recent years (L.J.V. Compagno pers. obs.), to testify that it is not extinct, however there is no information to suggest that the population status of this species has changed. There is an urgent need for a detailed survey of the shark fisheries of the Bay of Bengal.|
|Conservation Actions:||In 2001, the Indian government banned the landing of all species of chondrichthyan fish in its ports, although shortly afterwards, this ban was amended and now the Ganges shark Glyphis gangeticus is one of just ten species of chondrichthyans protected under Schedule I, Part II A of the Indian Wildlife (Protection) Act, 1972 (Government of India Ministry of Environment and Forests 2006). However, the effectiveness of this measure is unknown and these regulations may be difficult to enforce, with a diffuse but widespread artisanal fishery on a major river system for local consumption as well as international trade.|
Baillie, J. and Groombridge, B. (eds). 1996. 1996 IUCN Red List of Threatened Animals. pp. 378. International Union for Conservation of Nature, Gland, Switzerland and Cambridge, UK.
Compagno, L., Dando, M. and Fowler, S. 2005. A field guide to the sharks of the world. Harper Collins Publishers Ltd., London.
Compagno, L.J.V. 1984. FAO Species Catalogue. Sharks of the World: an annotated and illustrated catalogue of the shark species known to date. Part 2 - Carcharhiniformes. FAO Fisheries Synopsis No. 125, Vol. 4(2). FAO, Rome.
Compagno, L.J.V. 1984. The mysterious Ganges shark. Ichthos 7: 25-26.
Compagno, L.J.V. 1997. Threatened fishes of the world: Glyphis gangeticus (Müller & Henle, 1839) (Carcharhinidae). Environmental Biology of Fishes 40: 400.
Compagno, L.J.V. 2002. Freshwater and estuarine elasmobranch surveys in the Indo-Pacific region: threats, distribution and speciation. In: S.L. Fowler, T.M. Reed and F.A. Dipper (eds) Elasmobranch Biodiversity, Conservation and Management; Proceedings of the International Seminar and Workshop, Sabah, Malaysia, July 1997. IUCN SSC Shark Specialist Group. IUCN, Gland, Switzerland and Cambridge, UK
Compagno, L.J.V. 2005. Ganges shark Glyphis gangeticus. In: Fowler, S.L., Cavanagh, R.D., Camhi, M., Burgess, G.H., Cailliet, G.M., Fordham, S.V., Simpfendorfer, C.A. and Musick, J.A. (eds). Sharks, rays and chimaeras: the status of the Chondrichthyan fishes. pp. 305-306. IUCN Species Survival Commission Shark Specialist Group, IUCN, Gland, Switzerland, and Cambridge, UK.
Compagno, L.J.V. In prep. b. Sharks of the World. An annotated and illustrated catalogue of the shark species known to date. Volume 3. (Carcharhiniformes). FAO Species Catalogue for Fisheries Purposes No. 1, Vol.3. FAO, Rome.
Government of India Ministry of Environment and Forests. 2006. Schedule I, Part II A, Indian Wildlife Protection Act 1972. (Accessed on 15 November 2006).
IUCN. 2007. 2007 IUCN Red List of Threatened Species. Available at: www.iucnredlist.org. (Accessed: 12th September 2007).
IUCN SSC Shark Specialist Group. Specialist Group website. Available at: http://www.iucnssg.org/.
Martin, R.A. 2005. Conservation of freshwater and euryhaline elasmobranchs: a review. Journal of the Marine Biological Association U.K. 85(5): 1049-1073.
Roberts, T.R. 2005. Debunking the mythology of the so-called 'freshwater shark of the Ganges', Glyphis gangeticus (Elasmobranchii, Carcharhinidae). In: 7th Indo-Pacific Fish Conference. Howard International Hotel, Taipei, Taiwan. Academica Sinica, Taipei: Ichythological Society of Taiwan. [Abstract Book].
|Citation:||Compagno, L.J.V. 2007. Glyphis gangeticus. The IUCN Red List of Threatened Species 2007: e.T9281A12978210.Downloaded on 30 September 2016.|