| Tor putitora | |
|---|---|
_Babai_River.jpg) | |
| Babai River, Nepal | |
 | |
| Juvenile, about 35 cm (14 in) long | |
Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Order: | Cypriniformes |
| Family: | Cyprinidae |
| Genus: | Tor |
| Species: | T. putitora |
| Binomial name | |
| Tor putitora (F. Hamilton, 1822) | |
| Synonyms | |
| |
Tor putitora, the golden mahseer,putitor mahseer, orHimalayan mahseer, is anendangered species ofcyprinid fish that is found in rapid streams, riverine pools, and lakes in theHimalayan region. Its native range is within the basins of theIndus,Ganges andBrahmaputra rivers.[1] It was reported to be found in theSalween river, the natural border betweenThailand andMyanmar as well, but the number is very rare, only three times in 28 years.[2]
Thisomnivorous species is generally found near the surface in water that ranges from 13–30 °C (55–86 °F).[3]It is a populargamefish, once believed to be the largest species ofmahseer, and can reach up to 2.75 m (9.0 ft) in length and 54 kg (119 lb) in weight, though most caught today are far smaller.[4]
Its caudal, pelvic, and anal fins show tint of reddish-golden colour. While the body above its lateral line is generally golden in colour at adulthood, the gold colour might be absent in young specimens.
Hamilton's original description says "The head is blunt, oval, small, and smooth". He goes on to say "The mouth is small" and "the lateral line is scarcely distinguishable".[5] However, the largest head of any mahseer species, with a large mouth and prominent lateral line stripe, are features considered to be important in the correct identification of this species.
The golden mahaseer is theNational fish ofPakistan.[6][n 1] It is also the state fish of the states ofArunachal Pradesh,Himachal Pradesh,Uttarakhand,Odisha and the UT ofJammu and Kashmir.[7]
Nobel Prize winner for Literature - Rudyard Kipling, wrote: "There he met the mahseer of the Poonch, beside whom the tarpon is a herring, and he who catches him can say he is a fisherman." (Rudyard Kipling - "The Day's Work" 1898 - "The Brushwood Boy" 1899).
It is threatened byhabitat loss,habitat degradation andoverfishing, and it already has declined by more than an estimated 50%.[1]The prospect of large-scale dam building across the distribution range gives cause for concern reflected by the current Red Listing status.
Most researchers believe this fish is in a population decline, hence the Red Listing status of Endangered. Some, however, have noted thatTor putitora is "quite abundant",[8] which also raises questions about the status of ongoing stock augmentation programmes.
The golden mahseer is naturally found in montane and submontane regions within streams and rivers across the Himalayan region. Its habitat includes high-energy river systems with rocky substrates, and the species has shown adaptability to lacustrine environments formed by dam impoundments. Additionally, introduced populations have established in lakes where suitable habitats for reproduction are created by ephemeral stream inputs. The species' ability to thrive in varied environmental conditions underscores the importance of preserving both natural river ecosystems and artificial reservoirs for the sustainable conservation of this fish species in the South Himalayan region.[1]
Recent releases of artificially bred stock have been into theIrrawaddy River basin in Nagaland, India and, through the Indo-German Biodiversity Programme releases into the Hira Bambai reservoir and small streams aroundMelghat Tiger Reserve, part of theTapti River basin.[9] The effect of releasing fish from a different river basin, well outside its native range is uncertain. That these fish are being released over a ten-year period, with as many as 10,000 in each batch, must be considered a huge threat to the native mahseer and other fish species.[10]According to Dr Ogale, former scientist leading the fish breeding programme for Tata Power: "When these mature, there will be more fingerlings which will be then introduced in river Tapi".[11]River Tapi is a west-flowing river of the central Indian state ofMaharashtra.Golden mahseer from Lonavala hatchery in Maharashtra, India were supplied to the government ofPapua New Guinea[12][13] where the fish escaped into the localSepik river system after release into the Yonki reservoir. There are fears about the decline of native species following these introductions.[14]
primary threat toTor putitora is habitat loss and degradation, driven predominantly by the extensive development of hydropower projects in the Himalayan range. This anthropogenic impact poses a substantial risk to the species, as it results in the deterioration and reduction of essential habitats.[1]
Overfishing exacerbates the challenges faced byTor putitora, with unsustainable practices such as dynamiting, poisoning, and the use of fine-meshed nets contributing to a decline in populations. The impact of overfishing is notable in various river systems, affecting the species' overall population dynamics.[1]
