The Himalaya include all of the world's mountain peaks that exceed 8 000 m in height —including the world's tallest, Sagarmatha (Mt. Everest)— and several of the world's deepest river gorges. This is the youngest and the highest mountain chain on Earth, and stretches in an arc over 3 000 km across northern Pakistan, Nepal, Bhutan, the northwestern and northeastern states of India adjoining Myanmar, and the southwest China border in the east. This immense mountain range has been divided into two regions: the Eastern Himalaya, which covers parts of Nepal, Bhutan, the northeast Indian states of West Bengal, Sikkim, Assam, and Arunachal Pradesh, southeast Tibet (China), and northern Myanmar; and the Western Himalaya, covering the Kumaon-Garhwal, northwest Kashmir, and northern Pakistan (
Mani 1994). While these divisions are largely artificial (
Mani 1994), the deep defile carved by the antecedent Kali Gandaki River between the Annapurna and Dhaulagiri mountains has been an effective dispersal barrier to many species, and provides a biogeographic basis for defining the distinct Eastern and Western Himalaya along the length of the mountain range (
Wikramanayake et al. 2002). In total, the area covers some 741 706 km2.
Biogeographically, the Himalayan Mountain Range straddles a transition zone between the Palearctic and Indo-Malayan realms, with species from both contributing to its biodiversity. Understanding the distribution of biodiversity requires some knowledge of the genesis of the Himalaya, and the complex geological and physical features that influence patterns of biodiversity (
Molnar 1986). At about 45 million years, the Himalayan Mountain Range is geologically young. The mountains were formed as a result of geologic faulting during the massive collision between Eurasia and the northward-drifting Deccan Plate, which detached from the southeastern margin of Africa more than 200 million years ago. The subduction of the Deccan Plate raised the southern margin of Eurasia and, because the Deccan Plate is still moving northward, both Tibet and the Inner Himalaya continue to be pushed upwards even today.
The Himalayan Range now exerts considerable influence on weather patterns throughout most of South Asia. During the summer, a zone of low pressure forms over the Asian landmass, inducing a moistureladen monsoon wind from the Bay of Bengal to be funneled through the Ganges River Valley. The winds deluge the eastern extent of the mountain range, while the western extent remains drier. The water flows back into the Indian Ocean along the rivers that drain the southern slopes, carrying with them sediments eroded from the unstable, steep mountains. The sediments are deposited along the foothills to form extensive and highly productive alluvial plains of unconsolidated sediment traversed by innumerable braided rivers.
The abrupt rise of the mountains from less than 500 m to over 8 000 m results in a diversity of ecosystems that range over only a couple of hundred kilometers from alluvial grasslands and subtropical broadleaf forests along the foothills to temperate broadleaf forests in the mid hills, which transition into mixed conifer forests, and conifer forests in the higher hills and alpine meadows above the treeline. These ecosystems are layered as narrow bands along the longitudinal axis of the mountain range, and include several ecoregions (
Wikramanayake et al. 2002). But the rugged terrain also creates microenvironments within these ecoregions that harbor different ecological communities and assemblages. Thus, the biogeographic, climatic, geological, and altitudinal variations, as well as the topographic complexity, all combine to contribute to the biological diversity of the Himalaya along their east-west and north-south axes.
Below 1 000 m, the forests and open woodland savannas are dominated by drought-deciduous floral communities with affinities to the Indo-Chinese tropical monsoon forests. Characteristic species include dipterocarps, such as sal (Shorea robusta) on the Nepalese terai and Vatica lanceaefolia, Dipterocarpus retusus, D. turbinatus, and Shorea assamica in the Assam Valley further to the east. Low-lying areas, subject to floods during the monsoon, support mixed evergreen forests. The alluvial grasslands along the foothill valleys are among the tallest in the world. These grasslands are rejuvenated by silt deposited when the rivers that descend from the mountains overflow during the monsoon. As the floodwaters recede, grasses such as Saccharum spontaneum and pioneer trees such as Trewia nudiflora, Dalbergia sissoo, Acacia catechu, and Ehretia laevis begin to colonize the area, and the grasslands regenerate rapidly. These alluvial plains transition into the sal forests flanking the hills along the lower reaches of river valleys.
The lower hill slopes above 1 000 m tend to be cooler and less drought-stressed during the spring pre-monsoon season. Here, subtropical evergreen broadleaf forests are dominated by tree taxa (Castanopsis, Schima) derived from subtropical East Asia. This elevation supports a high diversity of trees, with variation in community composition dependent on aspect, disturbance regime, and human-use patterns. Adjacent to and north of the subtropical forest is a band of subtropical pine forest dominated by Chir pine (Pinus roxburghii) and extending across practically the entire length of the mountain range.
Temperate humid forests equivalent to “cloud forests” thrive at elevations where moisture tends to condense and remain in the air during the warm, moist growing season, from April to November. These forests are dominated by evergreen broadleaf trees (e.g., Quercus, Lauraceae) in the lower part (2 000–2 500 m) and a mixture of evergreen conifers (e.g., Tsuga, Taxus) and winterdeciduous broadleaf species (e.g., Acer, Betula, Magnolia) in the upper part (2 500–3 000 m). Drier, south-facing slopes support extensive stands of arboreal Rhododendron species that may co-occur with oaks (Quercus semecarpifolia) or other ericaceous species like Lyonia ovalifolia. At higher elevations, nearly monotypic stands of Rhododendron arboreum may give way to forests that include many a diverse community of shrubby rhododendrons. These cloud forests in the east are rich in epiphytes, represented by several dicotyledons and a variety of mosses, ferns, and orchids, and provide rich nesting habitat for many bird species. Malingo bamboo (Arundinaria spp.) in the understory is food for the charismatic red panda (Ailurus fulgens, EN). Overall, the wetter Eastern Himalaya is richer in species than the Western Himalaya, and is home to some of the most species-rich temperate forests in the world (WWF and ICIMOD 2001).
Subalpine conifer forests occur from about 3 000 to 4 000 m, high enough to receive substantial winter snow. These forests are identified by the dominant conifer species, which in the Eastern Himalaya are fir (Abies spectablis), larch (Larix griffithii), hemlock (Tsuga dumosa), and junipers. The western forests of the Eastern Himalaya have extensive stands of blue pine (Pinus wallichiana), chilgoza pine (P. gerardiana), silver fir (Abies pindrow), and spruce (Picea smithiana). Typically, the emergent conifers have tall, straight trunks that rise above the canopy. In the Eastern Himalaya, the subalpine forests also have many deciduous broadleaf trees tucked in among the taller, more obvious conifers. Typical broadleaf trees include Betula, Acer, Sorbus, Prunus, and some high-elevation members of the Lauraceae and Araliaceae families. Large evergreen Rhododendron shrubs are also an important component of this zone.
The rhododendrons above the treeline form alpine scrub communities throughout the wetter parts of the Himalaya. Dense shrubberies of juniper and Rhododendron clothe hill slopes to elevations of 4 500 m, and provide cover for many wild mammal species. Compared to the broadleaf and conifer forests, plant richness in the alpine shrub and meadow ecoregions is much greater. Moist alpine scrub is better developed on shady, northfacing slopes that are protected from extreme winter cold by an insulating layer of snow. South-facing slopes support meadows dominated by Kobresia sedge and dicotyledonous forbs with scattered shrubs such as Berberis, Rosa, Lonicera, Cotoneaster, and others to elevations of 4 500 m, while dwarf rhododendrons, Cassiope, Hippophae, Cotoneaster, and Potentilla fruticosa persist to 4 700 m where microclimatic conditions allow.
Periglacial and subnival communities occur in the high alpine areas ab
ove 4 700 m, where the short growing season, high winds, and restless soils require specialization for survival. Soil creep is an important physical factor influencing the physiognomy of plant communities at these elevations. Stable soils support slow-growing rosette or cushion plants. Because the perennial structures of cushion plants are sequestered underground, these plants can withstand high winds. Common genera include Androsace, Arenaria, and Saxifraga. Rosette plants grow in more sheltered locations and include at least two genera, Meconopsis (poppy) and Primula, which have their global centers of diversity in the Eastern Himalaya. Among the numerous other alpine herbs are Potentilla, Ranunculus, many legume species, and the spectacular alpine composite Saussurea.
Although the nival zone of permanent rock and ice begins at 5 500–6 000 m, vascular plants can survive in microclimates at the highest elevations on Earth. For example, Arenaria bryophylla, a small, tufted cushionforming plant with small, stalkless flowers, was recorded at 6 180 m by A.F.R. Wollaston in 1921 (Wollaston, in
Polunin and Stainton 1997). Other records of highaltitude flora include another cushion plant in the carnation family, Stellaria decumbans, at 6 140 m on the south slope of Makalu, and Ermania himalayensis, a highaltitude scree plant in the mustard family, at 6 300 m on the slopes of Mt. Kamet in the northwestern Himalaya.
Paleobotanical evidence indicates that much of the forest vegetation in the Himalayan Region is derived from the tropical evergreen forests of the Indian Peninsula, which was part of Gondwanaland, while the alpine flora evolved after the Himalayan uplift (
Ram and Singh 1994). Since this period, Pleistocene glaciation has influenced the flora and fauna, especially the southward migration of the species from the Central Asian, Alps, Mediterranean, and Sino-Japanese regions (
Gupta 1994). At the same time, physical and climatic barriers along the altitudinal transect, temperature extremes, and high intensity of ultraviolet radiation have resulted in high endemism, and evolution of mutants, polyploids, and ecotypes among several taxa.
The Himalaya are home to many unique and diverse human groups. Culturally diverse ethnic groups living in the river valleys and mountain slopes of the Himalaya differ from each other in terms of language, culture, tradition, religion, and patterns of resource use. Over 27 ethnic groups are found in Nepal, either of Tibetan-Burmese or Indo-Aryan descent, while Bhutan has three main ethnic groups: the Ngalongs, Sharchogpas, and Lhotsampas, all three of which are dominant, with many smaller groups with their own unique cultural practices. The northeast part of India, however, has over 500 distinct ethnic groups (
Stirn and Van Ham 2001). The people belong to numerous tribal groups with ancient cultures and traditions, although there is also a sizeable population of non-tribal groups as well.
Biodiversity
Of the estimated 10 000 species of vascular plants in the Himalayan region, approximately 3 160 are endemic. Angiosperms are divided into 192 families and 2 100 genera. The largest families of flowering plants are Orchidaceae (750 species), Compositae (734 species), Gramineae (520 species), and Fabaceae (507 species). The Eastern Himalaya is also a center of diversity for several widely distributed plant taxa, such as Rhododendron, Primula, and Pedicularis (
Sahni 1979).
The endemic flora are represented by 71 endemic genera, of which about 40 are confined to the Eastern Himalaya and about 15 to the Western Himalaya. The endemic genera include Jaeschkea, Parajaeschkea, Drimycarpus, Parrotiopsis, Listrobanthes, Megacodon, Pseudaechmanthera, Pseudostachyum, Pteracanthus, Sympagis, Catamixis, Physolena, Pottingeria, Roylea, Trachycarpus, and Triaenanthus. Drimycarpus and Parrotiopsis are monotypic genera that represent arborescent taxa, while Listrobanthes, Megacodon, Pseudaechmanthera, Pseudostachyum, Pteracanthus, Sympagis, and Triaenanthus are shrubs. Five families are endemic to the region, namely Tetracentraceae, Hamamelidaceae, Circaeasteraceae, Butomaceae, and Stachyuraceae, while over 90% of the species in Berberidaceae and Saxifragaceae are endemic to the Himalaya (
Singh et al. 2000).
A large number of orchids, many representing neoendemic taxa, have been recently reported from Sikkim and Arunachal Pradesh, which probably indicates that further exploration in the Himalaya will reveal a higher degree of plant endemism. Although many of the other non-vascular taxonomic groups have yet to be adequately documented, nearly 13 000 species of fungi and around 1 100 species of lichens have been described.
Overall, the fauna of the Himalaya is not well known; most of the information available for this region pertains to larger vertebrates, especially large mammals and birds that are easily observed. Smaller mammals, reptiles, amphibians, and fishes have been undersampled, while the insects have been largely ignored, with the exception of a few studies of the Himalayan Lepidoptera (e.g.,
Mani 1986;
Haribal 1992).
Around 300 mammal species have been recorded across the Himalayan Range, of which 12 are endemic to the Himalaya. The endemics include the golden langur (Trachypithecus geei, EN), which has a very restricted range in the Eastern Himalaya; the Himalayan tahr (Hemitragus jemlahicus, VU); and the pygmy hog (Sus salvanius, CR), a species restricted to grasslands in the Terai-Duar savannah and grasslands, with its stronghold in the Manas National Park. The Namdapha flying squirrel (Biswamoyopterus biswasi, CR) also represents the only endemic genus in the Himalaya, but is a poorly known species described on the basis of a single specimen taken from Namdapha National Park. The mammalian fauna in the lowlands is typically Indo-Malayan, consisting of langurs (Semnopithecus spp.), Asiatic wild dogs (Cuon alpinus, VU), sloth bears (Melursus ursinus, VU), gaurs (Bos gaurus, VU), and several species of deer, such as muntjac (Muntiacus muntjak) and sambar (Cervus unicolor). In the mountains, the fauna transitions into Palearctic species, consisting of snow leopard (Uncia uncia, EN), black bear (Ursus thibetanus, VU), and a diverse ungulate assemblage that includes blue sheep (Pseudois nayaur), takin (Budorcas taxicolor, VU), and argali (Ovis ammon, VU).
Around 979 bird species are recorded from across the region, with 15 endemics, including one species, the Himalayan quail (Ophrysia superciliosa, CR), which represents an endemic genus. However, it has not been recorded with any certainty since 1876 (although there were reports of possible sightings around Nainital in 2003). Four Endemic Bird Areas (EBAs), as defined by BirdLife International (
Stattersfield et al. 1998), overlap entirely or partly with the Himalaya Hotspot. The Western Himalaya EBA, which is almost entirely contained within the hotspot, has 11 bird species restricted entirely to it, including the aforementioned Himalayan quail, the cheer pheasant (Catreus wallichii, VU), and the western tragopan (Tragopan melanocephalus, VU), which is also endemic to the hotspot. The Central Himalaya EBA has two bird species confined entirely to within its boundaries, the spiny babbler (Turdoides nipalensis) and the Nepal wren babbler (Pnoepyga immaculata), and both are also endemic to the hotspot. The Eastern Himalaya EBA, which encompasses part of the Chin Hills (here considered part of the Indo-Burma Hotspot), has 19 bird species endemic to it, including the rusty-throated wren babbler (Spelaeornis badeigularis, VU), chestnut-breasted partridge (Arborophila mandellii, VU), white-throated tit (Aegithalos niveogularis), and orange bullfinch (Pyrrhula aurantiaca), all four of which are also endemic to the Himalaya Hotspot. Finally, the Assam Plains EBA is shared with the Indo-Burma Hotspot. The black-necked crane (Grus nigricollis, VU), a large bird of cultural and religious significance to the people in the Himalaya, spends the winters in the Himalayan region, but migrates into the wetlands of the Tibetan Plateau across the Himalayan Crest.
Systematic surveys of reptiles and amphibians are lacking for this hotspot, but it is known that at least 177 species of reptiles have been recorded, of which 49 are endemic. The lizard Mictopholis austeniana is the only representative of the sole endemic genus, but is known only from the holotype. Other genera are well represented, and have many endemic species. These include Oligodon (nine species, six endemic), Cyrtodactylus (10 species, seven endemic), and Japalura (seven species, all endemic). In terms of amphibians, 124 species are known to occur, and 41 species of these are endemic. The amphibian fauna is dominated by anurans, although two species of caecilians occur. One of these (Ichthyophis sikkimensis) is endemic and occurs in northern India (in the States of Sikkim and West Bengal) and extreme eastern Nepal (in Dabugaun in the Ilam District) at elevations of 1 000 to 1 550 m.
The Himalaya Hotspot has fish species from three major drainage systems, the Indus, Ganges, and Brahmaputra. However, the cold, steep high-altitude drainages have fewer fishes than the lowland rivers, and many species ranges only just reach into this hotspot; as a result, few species (33 out of 269) are endemic. The three most diverse of the 30 different families represented here are minnows and carps (Cyprinidae; 93 species and 11 endemics), river loaches (Balitoridae; 47 species and 14 endemics), and sisorid catfishes (Sisoridae; 34 species and four endemics). The genus Schizothorax is represented by at least six endemic species in the high mountain lakes and streams, while two other genera of these “snowtrout,” the genus Ptychobarbus and the Ladakh snowtrout (Gymnocypris biswasi) —a monotypic genus now thought to be extinct— are also unique to the Himalaya.
Flagship Species
The Himalaya support globally significant populations of several large mammals, including the tiger (Panthera tigris), Asian elephant (Elephas maximus), and greater one-horned rhinoceros (Rhinoceros unicornis, EN), in the foothill grasslands and forests. The range of the Asian elephant in the Himalayan Region is marginal; however, the populations along the north bank of the Brahmaputra River in Assam are one of India's largest and most important (
Sukumar 1992). The alluvial grasslands support some of the highest densities of tigers in the world (
Karanth and Nichols 1998), while the greater onehorned rhinoceros is restricted to several small, isolated populations within protected areas. The Eastern Himalayan Region is the last bastion for this charismatic megaherbivore with its armor-plated and prehistoric appearance. The Brahmaputra and Ganges rivers that flow along the Himalayan foothills also support globally important populations of the Gangetic dolphin (Platanista gangetica), a freshwater dolphin with two Endangered subspecies. It is endemic to the river system that flows along the foothills of the Himalayan Mountain Range. Dolphin populations are threatened by various human activities, including fishing, dams, and pollution, which affect both the animals themselves and their prey base.
Other flagships are wild water buffalo (Bubalus arnee) and swamp deer (Cervus duvaucelii), which are restricted to protected areas in southern Nepal and northeastern India, and represent some of the last remaining populations of these species in the world. The snow leopard has a wide distribution across the Himalaya, extending into the high mountains of the Trans-Himalaya, but the populations in the Himalayan Mountains are important because of the low density of this high-altitude predator.
Some of Asia's largest birds live in the Himalaya, and are represented by globally significant populations. Most are threatened by various anthropogenic causes, such as the vultures (Gyps spp.), which have undergone dramatic declines after feeding on carcasses of cattle that have been treated with Diclofenac (
Risebrough 2004). This is a classic example illustrating the effect of drugs and pesticides along the food chain. The greater and lesser adjutants (Leptoptilos spp.) in the foothill grasslands and broadleaf forests, as well as the hornbills in the broadleaf forests, are threatened by loss of nesting trees and lack of food sources. Other large birds include the sarus crane (Grus antigone), which inhabits the wetlands along the foothills; the black-necked crane, which spends winters in montane wetland sites; and the lammergeier (Gypaetus barbatus), which soars among the high mountains.
There are also several smaller mammals and birds that carry flagship status. The golden langur is a beautiful, golden-yellow primate that lives in the broadleaf forests between the Sankosh and Manas rivers in the Eastern Himalaya in both Assam and Bhutan, while the red panda inhabits the old-growth mixed conifer forests. The white-winged duck (Cairina scutulata, EN), the endemic white-bellied heron (Ardea insignis, EN), and the Bengal florican (Houbaropsis bengalensis, EN) are just a few of the other avian flagships in the region.
Threats
Despite their apparent remoteness and inaccessibility, the Himalaya have not been spared human-induced biodiversity loss. People have lived in the mountains and eked out a livelihood there for thousands of years. However, with better access to global market economies, both dependence on natural resources and the economic expectations and aspirations of the people have increased in recent years. Access has also encouraged immigration into montane areas from outside in some regions, such as Arunachal Pradesh, as well as movements within the Himalayan Mountains, such as in Nepal, where people have migrated from the mountains to the lowland terai. The consequences of the latter movements have been to concentrate people in the more productive ecosystems
that are also the richest in biodiversity, whereas the former have resulted in a breakdown of cultural and social traditions and ties to conservation of natural resources among the tribal people in the mountains. Moreover, better health care and disease control have resulted in a net increase of human populations, placing a greater burden on the sensitive montane ecosystems.
Today, the distribution of remaining habitat in the Himalaya is patchy. The steadily increasing human population has been responsible for extensive clearing of forests and grasslands for cultivation, and widespread logging. Cultivation has a soft, upper-elevation limit of around 2 100 m on slopes exposed to the monsoon, but many people farm crops like barley, potato, and buckwheat at higher elevations in the inner valleys and transmontane regions, and in some areas, such as Jumla, Kashmir, Lahoul, and Ladakh, there are major agriculturally based population centers well above this elevation. The land is also often cleared by pastoralists for their livestock during the summer months. The conversion of forests and grasslands for agriculture and settlements has led to large-scale deforestation and habitat fragmentation in Nepal, and in the Indian States of Sikkim, Darjeeling, and Assam. In the northeast Indian states, loss of dense forests is estimated to be as high as 317 km2 every year. The impact of forest clearing is less intense in Bhutan compared to the neighboring countries because of the low density of human population and the government's policy of a cautious approach to development and a commitment to the conservation of natural resources.
Large areas of remaining habitat are highly degraded. Overgrazing by domestic livestock in the resilient lowlands as well as in the sensitive alpine ecosystems is widespread. In the former, huge numbers of free-ranging, unproductive cattle graze the forests and grasslands, destroying all undergrowth and preventing regeneration; in the alpine ecosystems, virtually all areas are grazed by increasingly larger herds of domestic yak (
Miller 2002). The fragile meadows are also subject to overexploitation of their flora for the traditional medicine trade. Because the medicinal plant collectors invariably uproot entire plants, regeneration is retarded. Wood extraction for fuel and fodder also contribute to loss of undergrowth and regeneration, and changes in species composition. Fuelwood is collected for domestic consumption as well as for export. These activities have inflicted severe and sometimes irreversible damage, and in many areas forests are no longer able to support natural ecosystems and their associated biodiversity.
It is possible to make an estimate of natural vegetation remaining intact by considering the state of natural habitat of the various ecoregions that make up this hotspot (
Wikramanayake et al. 1998). The Himalayan subtropical broadleaf forests ecoregion has lost more than 70% of its natural habitat (although most of the hill forests above 1 000 m still remain uncut because the shallow, erosion-prone soils are unsuitable for cultivation), with the remaining forests in scattered fragments. Over 90% of the adjacent Terai-Duar savanna and grassland ecoregion has been converted to agriculture and settlements, and most of the remaining habitat is now within protected areas. The temperate broadleaf forests in the western extent of the Himalayan range have lost over 70% of their natural vegetation, although several large patches remain in the extreme western part. The eastern temperate broadleaf forests have fared better, with almost 70% of the natural habitat still remaining in large patches (particularly in northeastern India and Bhutan), but shifting agriculture has resulted in extensive habitat degradation. Likewise, the adjacent Brahmaputra Valley, a region characterized by remarkable productivity, and hence a long history of cultivation, is three-quarters cleared, with the largest forest blocks confined to protected areas in central Assam.
As with the temperate broadleaf forests, habitat loss in the Western Himalayan Sub-Alpine Conifer Forests is severe, with over 70% of the natural vegetation being lost. Notwithstanding, this region contains some of the leastdisturbed forests in the Western Himalaya. In the Eastern Himalaya, the reverse is true, although on gentler slopes within the northeastern hill states of India most of the broadleaf forests (over 80%) have been affected due to slash-and-burn (jhum) agriculture. Most of the Alpine Shrub and Meadows is remote and inaccessible and, consequently, largely intact thanks to high elevation and harsh climate. However, all the gentle and accessible meadows have undergone extensive habitat degradation due to overgrazing, trampling, and commercial harvest for medicinal plants. In total, then, nearly 50% of the alpine vegetation in the region can be said to be intact, although in Sikkim, Bhutan, and Arunachal, over 60% of the alpine vegetation is still intact. Since this degradation can not be estimated from remote-sensed data sources, it is difficult to assess its extent, as grazing is prevalent all throughout the alpine regions. In total, we estimate that around 25% of the original vegetation of this hotspot, including alpine areas, remains in intact condition.
Besides habitat loss and degradation, poaching is rife across the Himalayan Mountains: tigers and rhinoceros are hunted for their body parts, which are much prized in traditional Chinese medicines, while the snow leopard and red panda are taken for their beautiful pelts. The remoteness of the Himalayan Region and the open borders have facilitated this illegal trade.
Political unrest, usually in the form of insurgencies, plague certain sites in the Himalayan region. Protected areas and forests that harbor wildlife also serve as refuges for insurgents, who indulge in indiscriminate poaching and felling of trees to obtain funds. In Nepal, the Maoist insurgency has severely constrained conservation activities on the ground since 1996. Similar insurgencies occur in Assam and Nagaland in India, while the dispute between India and Pakistan over the Kashmir border has had implications for wildlife conservation in these areas.
Conservation
Approximately 15% of the Himalaya Hotspot has some form of legal protection, although this percentage drops to 10% when one considers only those in IUCN categories I to IV. Protected areas have a mixed history in the Himalaya. In Assam, Manas and Sonai Rupai were first established as wildlife sanctuaries in 1928 and 1934, respectively, and are among the earliest contemporary protected areas in Asia (
IUCN 1990). Most other protected areas are relatively recent, having been established within the past three to four decades. However, many hill-tribe communities have traditionally recognized and protected sacred groves, which have been effective refuges for biodiversity for centuries (
Gadgil, 1985). Today, several protected areas —Corbett National Park, Manas National Park, Kaziranga National Park, Chitwan National Park, and Sagarmatha National Park— have been distinguished as World Heritage Sites for their contribution to global biodiversity.
In the 1970s and 1980s, several protected areas were established or extended in the northeastern Himalayan states of India, creating a network that showcased the biodiversity in the area. The protected areas in the northwestern Indian states include some of the world's most renowned, such as Corbett and Rajaji national parks, which harbor important populations of flagship species like elephants and tigers.
In Nepal, at least 26 666 km2 of land has been designated as protected areas, including eight national parks, four wildlife reserves, one hunting reserve, three conservation areas, and five buffer zones (
WWF-Nepal 2004). Chitwan, the country's first national park, was established in 1973. Previously a hunting preserve for the royal family, the park is well known for its tiger and greater one-horned rhinoceros populations. Of particular significance are the Annapurna Conservation Area, the Kanchenjunga Conservation Area, and the Makalu-Barun National Park, which have become models for community-based biodiversity management.
The protected area system of Bhutan includes five national parks, three wildlife sanctuaries, and one strict nature reserve, as well as 12 corridors covering almost 16 000 km2 (
Biodiversity Action Plan 2002). The current system was bequeathed as a “Gift to the Earth from the People of Bhutan” in 1999. Although a protected area system was established in Bhutan as early as the 1960s, this system was dominated by the Jigme Dorji Wangchuck National Park. The park was mostly confined to the north of the country, and did little to contribute towards biodiversity conservation because most of the park protected vast areas of permanent rock and ice. In 1995, the protected area system was revised to include all nine of the current protected areas accounting for almost 26% of the total land area in Bhutan. In 1999, another 9% was added to the system in the form of biological corridors, which linked the protected areas to create a conservation landscape extending across the country. The landscape is known as the Bhutan Biological Conservation Complex (
Sherpa et al. 2003).
The many protected areas that lie adjacent to each other across national borders present promising opportunities for transboundary conservation activities. The Manas National Park in Bhutan and Manas Tiger Reserve in Assam, India is one such complex. Biological corridors also provide opportunities to link the protected areas across international boundaries and create habitat linkages, such as between Bardia in Nepal and Katerniaghat in India. Another important transboundary initiative is Kanchanjunga Conservation Area (KCA) in the Taplejung District in Nepal, an area covering some 1 650 km2 named for Mt. Kanchanjunga (8 586 m) —the third highest mountain in the world— and planned as a tri-national peace park with the Tibet Autonomous Region of China to the north, and Sikkim in India to the east. The Kanchanjunga Conservation Area adjoins the Kanchendzoga National Park in Sikkim, and extension of the Qomolungma Nature Reserve in the Tibet Autonomous Region is under way to include the area bordering Kanchanjunga. The new strategy for creating conservation landscapes in the Himalaya will not only help to conserve the region's species and ecological processes that sustain biodiversity, but also contribute towards building regional cooperation through transboundary conservation efforts, thereby paving the way for a secure future for Himalayan biodiversity.
Despite the efforts to revise the protected area system across the Himalayan Mountains, about 17% of it, or over 40 000 km2, still consists of permanent rock and ice (
Alnutt et al. 2002). The protected areas of the alpine regions, in particular, are over-represented by these biologically depauperate habitats. Across the range, 15 protected areas consist of more than 50% rock and ice. Further expansion of the protected area network should consider minimizing representation of these areas.
Investment in biodiversity conservation in the Himalayan Region comes primarily from national governments, bilateral and multilateral agencies, and international and regional NGOs. The national governments, backed by international agencies such as the Global Environmental Facility (GEF), United Nations Development Program (UNDP), the World Bank, the European Union (EU), the Danish International Development Agency (DANIDA), WWF, and the MacArthur Foundation, are supporting projects to improve protected area management, sustainable natural resources, and livelihoods. All countries in the Himalaya Hotspot have ratified the Convention on Biological Diversity, and have prepared National Biodiversity Conservation Strategies and Biodiversity Action Plans.
While there have been many successes in establishing protected areas and more experimental, multiple landuse conservation areas, much remains to be done to safeguard the biological wealth of the Himalayan Region currently lying outside formally protected reserves. The protected areas of the Himalaya, particularly in the lowlands along south-facing slopes, are too small to maintain viable populations of threatened species. Successful longterm conservation requires that efforts be made to expand the conservation benefits beyond existing protected areas to adjacent habitats, as many species are dependent upon the seasonal use of habitats distributed along elevational gradients and across national boundaries.