|Original illustration of Tor tor by Haludar 1822|
Tor tor, commonly known as the tor mahseer or tor barb, is a species of cyprinid fish found in fast-flowing rivers and streams with rocky bottoms in India, Bangladesh, Bhutan, Nepal, and Pakistan. It is a commercially important food and game fish.
In the Himalayan rivers, the population is rapidly declining through its native range, including some evidence of catastrophic collapse, due to pollution,overfishing, the effects of dam building, climate change and introductions of other mahseer species. Until the 1980s, Tor tor was the most populous of the Himalayan mahseers in those rivers where robust species diversity monitoring had taken place.
There are also declining populations in rivers of Central India, including north-flowing tributaries of the Ganges/Yamuna basin, the Narmada basinand as far south as the Savitri River in Maharashtra. Given the huge differences in climatic and riverine conditions, careful work on species identity is needed to establish if these mahseer are also Tor tor, or an undescribed species.
It is a large fish, reaching 36 cm (14 in) at maturity, but lengths of 150 cm (4.9 ft) have been recorded, but the maximum length is 200 cm. The fish is well armoured by their record large scales, each reaching up to 10 cm (3.9 in) in length.
The main species found in Central India is the state fish of Madhya Pradeshwhile the sub-species found in Mahanadi river, known as Tor mosal mahanadicus (Mahanadi mahseer) is the state fish of Odisha.
A close look at the giant red-finned mahseer of Himalayan rivers suggests it is adapted to feeding on the bottom. Having a sub-terminal or inferiormouth and being equipped with barbels, small sensory organs dangling from the corners of the mouth, usually imply that this fish feeds on or in the river's substrate. This could be an explanation for how multiple species of mahseer inhabit the same river habitats.
Another element that requires more study is that the co-habiting species Tor putitora accesses tributaries at higher elevations than Tor tor for spawning success.These papers show that while some research has been conducted into the breeding habits of the golden mahseer, little work has been done on Tor tor, possibly because of the alarming decline in populations.
Among the most pressing issues relating to the conservation of this fish are that it cannot be correctly identified. Although many papers have been published on Tor tor, most are written about studies of fish from the Narmada River of central India, none cross-reference to fish from the type locality: Mahananda River of West Bengal. The uncertainty of identity is the reason for the IUCN Red Listing status of Data Deficient.
While there are reports of a few, large fish which appear to fit the description of Tor tor in some rivers of the Himalayan region, anecdotal reports from anglers suggest that there are very few juvenile fish. This may demonstrate that spawning behaviours have been changed, due to a number of possible factors, but dam building is one of the most likely culprits. The planned Pancheswar Dam on the Sarda River (also called Mahakali River when shared by Nepal) will halt the migration of all freshwater fauna, including mature Tor tor.Climate change is likely to have a devastating effect on fish species of the Himalayas, due to a combination of increased flows from glacial melt and rising temperatures due to both a generally warmer local climate and the effect of impoundments.
Releases of non-native fish are also having an impact upon fish of Himalaya, like Tor tor.
Calls for stock reinforcement through stocking are understandable, but have often caused more problems for wild stock. A correct and long-term study of relative species populations will be needed prior to any attempt to recover stocks through artificial breeding.
As has been demonstrated previously, attempts to restock without an adequate understanding of species ratios, or by using incorrect species, can have catastrophic effects upon the target species for a conservation plan.
The Ganges or Ganga is a trans-boundary river of Asia which flows through India and Bangladesh. The 2,525 km (1,569 mi) river rises in the western Himalayas in the Indian state of Uttarakhand, and flows south and east through the Gangetic Plain of North India into Bangladesh, where it empties into the Bay of Bengal. It is the third largest river on Earth by discharge.
India lies on the Indian Plate, the northern part of the Indo-Australian Plate, whose continental crust forms the Indian subcontinent. The country is situated north of the equator between 8°4' north to 37°6' north latitude and 68°7' east to 97°25' east longitude. It is the seventh-largest country in the world, with a total area of 3,287,263 square kilometres (1,269,219 sq mi). India measures 3,214 km (1,997 mi) from north to south and 2,933 km (1,822 mi) from east to west. It has a land frontier of 15,200 km (9,445 mi) and a coastline of 7,516.6 km (4,671 mi).
The Himalayas, or Himalaya ; Sanskrit: himá and ā-laya, is a mountain range in South and East Asia separating the plains of the Indian subcontinent from the Tibetan Plateau. The range has many of Earth's highest peaks, including the highest, Mount Everest, at the border between Nepal and China. The Himalayas include over fifty mountains exceeding 7,200 m (23,600 ft) in elevation, including ten of the fourteen 8,000-metre peaks. By contrast, the highest peak outside Asia is 6,961 m (22,838 ft) tall.
Tor is a genus of cyprinid fish commonly known as mahseers.
Mahseer is the common name used for the genera Tor, Neolissochilus, Naziritor and Parator in the family Cyprinidae (carps). The name is, however, more often restricted to members of the genus Tor. The range of these fish is from Vietnam in the north and China in the south, through Laos, Cambodia, Thailand, Malaysia, Indonesia, and across southern Asia including the Indian Peninsula, Sri Lanka, Pakistan and Afghanistan. They are commercially important game fish, as well as highly esteemed food fish. Mahseer fetch high market price, and are potential candidate species for aquaculture. Several of the larger species have suffered severe declines, and are now considered threatened due to pollution, habitat loss, overfishing and increasing concern about the impacts of unregulated release of artificially bred stock of a very limited number of species.
Bhimtal Lake is a lake in the town of Bhimtal, in the Indian state of Uttarakhand, with a masonry dam built in 1883 creating the storage facility. It is the largest lake in Kumaon region, known as the "lake district of India". The lake provides drinking water supply and supports aquaculture with variety of fish species. There is an island at the centre of the lake which has been developed as a tourist attraction and has an aquarium.
Maharana Pratap Sagar in India, also known as Pong Reservoir or Pong Dam Lake was created in 1975, by building the highest earthfill dam in India on the Beas River in the wetland zone of the Siwalik Hills of the Dehra Gopipur Division Kangra district of the state of Himachal Pradesh. Town of Gopipur is submerged in the reservoir, many families were displaced while flooding of reservoir. Named in the honour of Maharana Pratap (1540–1597), the reservoir or the lake is a well-known wildlife sanctuary and one of the 27 international wetland sites declared in India by the Ramsar Convention. The reservoir covers an area of 24,529 hectares, and the wetlands portion is 15,662 hectares.
Tor khudree, the Deccan mahseer, Khudree mahseer, or black mahseer, is a freshwater fish of the carp family found in major rivers and reservoirs of India and Sri Lanka. Found throughout India, following large-scale introductions of artificially-bred fish across the country, but found of the largest size and in the greatest abundance in mountain or rocky streams.
The fish as originally described by Sykes in his November 1838 paper 'On the Fishes of the Dukhun' as Barbus khudree, is a silvery-bluish coloured fish, with blood red fins or fins tipped with a bluish tinge. The type locality is the Mula-Mutha River close to the Indian city of Pune, a part of the Krishna River basin.
Although there have been efforts to artificially breed this mahseer since the early1970's, there is no way to determine if these fish are Tor khudree, as the populations within the type locality have gone extinct.
Tor putitora, the Putitor mahseer, Himalayan mahseer, or golden mahseer, is an endangered species of cyprinid fish that is found in rapid streams, riverine pools, and lakes in the Himalayan region. Its native range is within the basins of the Indus, Ganges and Brahmaputra rivers. It is a popular gamefish, once believed to be the largest species of mahseer, 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. It is threatened by habitat loss, habitat degradation and overfishing, and it already has declined by more than an estimated 50%. This omnivorous species is generally found near the surface in water that ranges from 13 to 30 °C (55–86 °F).
Nainital Lake, also known as Naini Lake a natural freshwater body, situated amidst the township of Nainital in Kumaon, tectonic in origin, is kidney shaped or crescent shaped and has an outfall at the southeastern end.
Royal Manas National Park is Bhutan's oldest national park, and the Royal government considers it the "conservation showpiece of the Kingdom" and a "genetic depository" for valuable plants. It has an area of 1,057 square kilometres (408 sq mi) and covers eastern Sarpang District, the western half of Zhemgang District, and western Pemagatshel District.
Tor douronensis, also known as Labeobarbus douronensis, is a species of ray-finned fish of the family Cyprinidae in the genus Tor. This Asian fresh water river carp can be discovered in southern Thailand, east to Vietnam and south to Indonesia. The species is known from the Chao Phraya and Mekong rivers.
This fish has been attributed to Valenciennes however, in his original notes, he claims that the fish he described "formed part of the collection made in Java by Kuhl and Van Hesselt; they named it Dourr." Certainly, the type locality is Java, in Indonesia and the holotype is lodged at Bogor Zoology Museum.
Tor tambroides, known as empurau in Malay, is a species of mahseer native to Southeast Asia.
Tor sinensis, the Chinese or Red mahseer is a species of mahseer native to the Mekong River. It is known with certainty only from Yunnan, China; reports from Cambodia, Laos, and Thailand require confirmation.
It is one of four currently valid species described from China, the others being Tor laterivittatus, Tor polylepis, and Tor yingjiangensis.
The humpback mahseer is a species of freshwater ray-finned fish from the Indian endemic genus Hypselobarbus in the carp and minnow family Cyprinidae.
Tor remadevii, the orange-finned mahseer, also known as the hump-backed mahseer, is a critically endangered species of freshwater fish endemic to the Western Ghats of India. It is restricted to the Kaveri river basin.
Tor ater, the dark mahseer, is a species of mahseer, a fish, native to Central Laos.
Tor barakae is a species of mahseer native to Manipur, India.
Tor malabaricus, the Malabar mahseer, is a fish, a species of mahseer native to southwestern India.