|Marine||No||Shrestha, T.K., 1990|
|Freshwater||202||38||No||129||Shrestha, T.K., 1990|
|Total||204||38||No||129||Talwar, P.K. and A.G. Jhingran, 1991|
|Conservation||Information about the current conservation status of Nepalese fishes is good. A Red Data Book of the Fauna of Nepal has been published (Suwal et al., 1995; Ref 12044) and A Conservation Strategy for Fishes of Nepal has been prepared by Tej Kumar Shrestha, the outline of which is presented below. Threats to fishes in Nepal come from a variety of sources. In major rivers dams and barrages have been constructed for the purposes of hydro-electric power generation and navigation. The dams do not have fish-ladders and thus obstruct the upstream and downstream migrations of fish. Rare species of migratory fish are also affected by subsequent changes in water velocity and fluctuating levels that sometimes expose the spawning areas. The shallow tailwater regions behind dams where fish congregate are exploited by fisherman, poachers and predatory animals threatening the rare stone carps, loaches and catfishes. The population of Nepal has increased greatly in recent years with resulting increase in pollution by domestic and industrial wastes. The fish population througout the country has declined due to destructive fishing techniques such as use of dynamite, poisons, fine mesh gillnets, and electrocuting. Chemical fishing has recently been reported as a threat to the whole ecosystem of Kosi Tappu. This practice not only decimates fish populations but is also probably a major factor in the decline of waterbird populations in this area. Removal of driftwood from rivers has an adverse effect on the spawning habitat and natural nursery of fish fry . Fishing during the spawning period limits population recruitment. Spawning beds are being removed to provide sand and gravel for the building industry. Changes in land use and deforestation are causing soil erosion with resultant increase in the silt load of rivers in the rainy season. The major river systems of Nepal consist of the Koshi in the east, Gandaki in the central and Mahakali and Karnali in the western part of the country. These rivers support a diverse variety of fishes that are important both from a food and recreational point of view. Lower reaches of rivers and hill streams are generally polluted by domestic waste. It is certain that pollution in Nepalese rivers is increasing. 1. Mahakali River This is a perennial, torrential river that originates from the Milan glacier near the Indian border. The water is clear throughout the year except during the rainy season. There are many small scale water mills, industry and power stations situated in the lowland catchment area. The Sarada and Tanakpur barrage is located in the lower reaches of the Mahakali River. 2. Karnali River This is a perennial, torrential, turbulent and undisturbed river of the Himalayas. It originates from the Mansarovar and Rakas lake and receives many snow-fed rivers such as Mugu Karnali and Humla Karnali in the Himalayan belt. It flows through a spectacular gorge near Chisapani which contains many kinds of trans-Himalayan and sub-Himalayan fish species of Indo Chinese affinities. This river carries a high sediment load. The upland watershed of this river is sparsely populated and as a whole it suffers least from human interference. 3. Koshi River This is perennial river rising from the Pei-ko-Tso and Tso-Nu-Che lakes in Tibet. It has a number of tributaries including the Sun Koshi, Dudh Koshi, Tama Koshi, Likhu, Arun, Tamur and Indrawatti. One of the tributaries, the Arun, supports the largest concentration of rare ornamental fish species in Nepal. 4. Narayani River This is a perennial torrential river that originates from the southern slope of the Himalayas. It has a number of tributaries including the Kali Gandaki, Budi Gandaki, Trisuli, Marsyangdi, Made and Seti rivers. The river is heavily polluted by domestic and industrial wastes. Fish kills have been documented in recent years. Many low dams and barrages have been put across the river and these need to modified to allow the passage of fishes. The Nepalese government has taken a more active interest in protecting fish species. It is important that fish sanctuaries be created in major river systems within Nepal. To date, studies of the fishes of Nepal have centered on a few Himalayan species in the midland river valleys. There is a great need to study the ecology and behaviour of species in the Narayani, Karnali, Koshi and Mahalaki river valleys. There is an urgent need to assess the status of Himalayan, sub-Himalayan and tropical fish species within Nepal. More information on fisheries activities is required and an environmental education program should be undertaken to inform fisherman of the importance of rare Himalayan fishes. For the long-term conservation of fishes, effective policies are needed that can be implemented by the non-governmental sector (e.g. National Parks and Wildlife Department, Tribhuvan University, Royal Nepal Academy of Science and Technology, King Mahendra Trust for Nature Conservation, International Center for Mountain Development). The following suggestions are made: 1. Detailed surveys of status and distribution of fishes in Nepal are urgently needed to assist in the drafting of management plans; 2. Conservation of the @Schizothorax@ and @Tor@ species in Nepal through the designation of wildlife sanctuaries and biosphere reserves; 3. Inventory of fisheries resources with the aim of protecting genetic resources; 4. Preparation of information on rare fishes and the development of reporting systems to help disseminate this; 5. Studies of the ecology and behaviour of cold Himalayan rock carps and stone carps; 6. Captive breeding of important ornamental fish species; 7. Status and distributional range of species throughout the Himalayan range of Nepal, India, Pakistan and Bangladesh should be re-investigated. Threatened Species Ten of the 180 species of fish in Nepal merit Red Data Book status (Suwal et al., 1995; Ref. 12044). The majority of these species belong to the genera @Labeo@ (five species), @Puntius@ (five species) and @Schizothorax@ (three species). The species suggested for Red Data Book status are as follows (but note remarks): Name: @Acrossocheilus hexagonolepis@ Local name(s): Katle Distribution: Kosi, Gandaki, Karnali, Mahakali Status: VULNERABLE Name: @Chagunius chagunio@ Local name(s): Patharchatti, Rewa, Kubre, Chaguni, Khaisala, Koshinu Distribution: Kosi, Gandaki, Karnali, Mahakali Status: VULNERABLE Name: @Oreichthys casuatis@ Local name(s): Patharehatti Distribution: Gandaki Status: ENDANGERED Remark: Maybe an empty name (nomen nudum), Eschmeyer, pers. comm. Identification and status need confirmation. Name: @Puntius chola@ Local name(s): Sidre, Pothi Distribution: Kosi Status: ENDANGERED Name: @Puntius guganio@ Local name(s): ? Distribution: Gandaki Status: ENDANGERED Remark: Not occurring in Nepal according to Refs. 6351, 12045, 4832. Identification and status need confirmation. Name: @Tor putitora@ Local name(s): Mahaseer Distribution: Kosi, Gandaki, Karnali Status: VULNERABLE Name: @Tor tor@ Local name(s): Sahar Distribution: Gandaki, Mahakali Status: ENDANGERED Name: @Barilius jalkapoorei@ Local name(s): Jalkapoor, Totiyara Distribution: Kosi, Bagmati, Narayani Status: VULNERABLE Remark: This species has not been reviewed by other taxonomists after it's original description by Shrestha in 1978. Identification and status need confirmation. Name: @Barilius radiolatus@ Local name(s): Fageta, Jalkapur Distribution: Trishuli Status: ENDANGERED Remark: According to Ref. 4832, this species is endemic to India. Also not listed in Shrestha 1990a,b (Refs 6351, 12045). Identification and status need confirmation. Name: @Danio rerio@ Local name(s): Zebra, Sano dedhawa Distribution: Gandaki, Karnali Status: VULNERABLE|
|Geography and Climate||
A landlocked country, the greater part of Nepal is in the Himalayas with access to some of the world's highest mountains including Everest and Kanchenjunga, both well over 8,500 m. Approximately 75% of the land is occupied by mountains. The Terai, a belt of lowland along the southern border is the only area of flat land. The country can be divided into four physical belts, each extending east-west across the country: (a) the Terai, the low, flat fertile land close to the border with India; (b) the forested Churia foothills and the inner Terai zone rising from the Terai plains to the rugged Mahabharat Lekh range; (c) the mid-mountain region between the Mahabharat Lekh range and the outer Himalayas; and (d) the Great inner Himalayan range rising to more than 8,800 m.
The climate of Nepal is greatly influenced by altitude and latititude. Generally, subtropical monsoon conditions prevail in the Terai region. A warm temperate climate occurs at altitudes of between approximately 1,200 and 2,100 m. In the Himalayan belt at 2,400 to 3,300 m, cool temperate conditions prevail. An alpine climate predominates at altitudes between 4,200 and 4,800 m. At an altitude of more than 4,800 m the temperature is always below freezing and the land surface covered by snow and ice. In the eastern portion of the Terai rainfall is around 175 cm a year. The western portion of Nepal is dry.
Ref. Shrestha, T.K., 1990
The Kathmandu Valley is watered by the Bagmati River, flowing southward through the deep Chhobar gorge. Drained by the Seti River, the Pokhara valley, west of Kathmandu, is also a flat lacustrine basin. There are a few natural lakes in the Pokhara valley, the most noteworthy being the Begnas, Rupa, Maidi and Dipang. The major rivers of Nepal, the Koshi, Gandaki and Karnali, flow southwards through steep valleys and gorges. The watershed of these rivers usually lies within Tibet. Lower reaches of the rivers and low-lying areas of the Terai are prone to serious flooding.
Streams, reservoirs, village ponds and irrigated rice-fields together constitute the 7,131,380 ha of inland water resources. Rice-fields alone account for 45% of this area. Among the rest, 97% is occupied by the 6,000 rivulets and streams that cut through the mountains and plains.
The fishes of the Himalayan waters of Nepal are biologically diverse (Hora, 1937, Ref. 12042; Menon, 1974, Ref. 12043). More than 130 species occur in the snow-fed rivers and mountain lakes of the Nepalese highlands. Of the major rivers, Koshi has 108 species, Narayani has 102, Karnali has 74 and Mahakali has 69 (Shrestha, 1990).
A freshwater sites of exceptional biodiversity interest is Lake Rara with rich invertebrate fauna and species of @Schizothorax@.
Ref. Shrestha, T.K., 1990