Tor mahseer | |
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Original illustration of Tor tor by Haludar 1822 | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Order: | Cypriniformes |
Family: | Cyprinidae |
Genus: | Tor |
Species: | T. tor |
Binomial name | |
Tor tor (Hamilton, 1822) | |
Synonyms [2] | |
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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, [3] 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. [4] [5]
There are also declining populations in rivers of Central India, including north-flowing tributaries of the Ganges/Yamuna basin, the Narmada basin [6] [7] and as far south as the Savitri River [8] 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, [1] [2] but the maximum length is 200 cm. [9] The fish is well armoured by their record large scales, each reaching up to 10 cm (3.9 in) in length. [10]
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 inferior [11] mouth 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. [12] This could be an explanation for how multiple species of mahseer inhabit the same river habitats. [13]
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. [14] [15] 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. [16] 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. [17] [18]
Releases of non-native fish are also having an impact upon fish of Himalaya, like Tor tor. [19] Given the high incidence of Buddhist belief in the region, many of these are inadvertent 'liberation' of highly invasive species, both fish and other organisms like turtles and frogs. [20]
Calls for stock reinforcement through stocking are understandable, but have often caused more problems for wild stock. [21] 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, [22] 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 Himalayas, or Himalaya is a mountain range in Asia, separating the plains of the Indian subcontinent from the Tibetan Plateau. The range has some of the Earth's highest peaks, including the highest, Mount Everest. More than 100 peaks exceeding elevations of 7,200 m (23,600 ft) above sea level lie in the Himalayas.
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 east and China in the north, through Laos, Cambodia, Thailand, Malaysia, Brunei and Indonesia, and across southern Asia including the countries of India, Nepal, Bhutan and Bangladesh within the Indian Peninsula, plus 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 is a lake in the town of Bhimtal, near Nainital city in Nainital district of Kumaon, India with a masonry dam built in 1883 creating the storage facility. It is the largest lake of Nainital district, as well as Kumaon, which is known as the "Lake district of India".
Maharana Pratap Sagar, also known as Pong Reservoir or Pong Dam Lake is a large reservoir in Fatehpur, Jawali and Dehra tehsil of Kangra district of the state of Himachal Pradesh in India. It was created in 1975, by building the highest earthfill dam in India on the Beas River in the wetland zone of the Siwalik Hills. Named in the honour of Maharana Pratap (1540–1597), the reservoir or the lake is a well-known wildlife sanctuary and one of the 49 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.
The Manas River, known in Bhutan as the Drangme Chhu, is a transboundary river in the Himalayan foothills between southern Bhutan, India, and China. It is the largest of Bhutan's four major river systems, with the other three being the Amo Chu or Torsa River, the Wang Chu or Raidak, and the Puna Tshang Chu or Sankosh. It is met by three other major streams before it again debouches into India in western Assam. The river flows for a total length of 400 kilometres (250 mi), including through Tibet for 24 km (15 mi), Bhutan for 272 kilometres (169 mi), and Assam for 104 kilometres (65 mi) before it joins the mighty Brahmaputra River at Jogighopa. A major tributary of the Manas, the Aie River, joins it in Assam at Bangpari.
Tor putitora, the Golden Mahseer, Putitor mahseer, or Himalayan 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 was reported to be found in the Salween river, the natural border between Thailand and Myanmar as well, but the number is very rare, only three times in 28 years.
The common snowtrout or snowtrout, also known as "Asala", or "Asela" by the locals, is a species belong to the class of ray-finned fishes, family Cyprinidae, order Cypriniformes in the genus Schizothorax. The genus name Schizothorax is derived from Greek word, "schizein" meaning to divide, and "thorax" which means breast.
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.
B. Madhusoodana Kurup is an Indian fisheries researcher, academic and administrator. He is the Founder Vice-Chancellor of Kerala University of Fisheries and Ocean Studies (KUFOS), Cochin and also served as the third Vice Chancellor of Shri Venkateshwara University, Gajraula, Uttar Pradesh. He has established and successfully developed the first Fisheries and Ocean Sciences University in the country. He did his postdoc from Fish Culture and Fisheries division, Wageningen University & Research, The Netherlands. He served as UGC Professor (Fisheries) at Cochin University of Science and Technology (CUSAT) for over eighteen years.
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 tambra, the Javan mahseer, is a species of mahseer native to Southeast Asia.
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.
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