CHAPTER 1 1. Introduction: Background of the study and rationale

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1 CHAPTER 1 1. Introduction: Background of the study and rationale The Himalaya as being one of the youngest of the world s mountain chains (Sherpa et al., 2004) is well recognised for its ecological, socio-cultural and aesthetic values. The outstanding peculiarities of the ecology of the Himalaya may be traced to its enormous massiveness, the great elevations of the mountain ranges, their trendline, and their location in the middle of vast continental masses. The Himalaya, being the meeting point of three biogeographic realms, viz., Palaearctic, Africo-tropical and Indo-Malayan (Mani,1974) encompasses wide variety of habitats that were occupied by many primitive as well as newly evolved species (Bhattacharya, 2013). The Himalaya and Trans-Himalaya are important biogeographic zones in India (Rodgers & Power, 1988) and spread over the six Indian States of Jammu and Kashmir, Himachal Pradesh, Uttarakhand, Sikkim, northern parts of West Bengal and Arunachal Pradesh covering ca. 12% of the country s 3.3 million km 2 geographical area (Ghosh, 1996). Biogeographically, the Himalaya is categorized into four provinces viz. Northwestern, Western, Central and Eastern; and the Trans-Himalaya is categorized into two biotic provinces viz., Ladakh mountains and Tibetan Plateau (Rodgers et al., 2000). The interesting patterns of biogeography characterized by the high degree of endemism and localized distribution are very much relevant for several rare, endangered and economically important flora and fauna. The abundant rainfall in the mountains ensure prosperity of the people living in the Indo-Gangetic plains as they impede the northward flow of the monsoon clouds and their geographic positions from the watershed for the rivers flowing in northern India. But changing land use patterns and developmental activities in the Himalaya have led to the shrinkage of the forest cover of these important watershed areas of the country and simultaneously degraded much of the prime wildlife habitats. Eastern Himalaya comprises the lowlands and montane regions of central and eastern Nepal; the state of Sikkim, the mountains of northern West Bengal in India including Darjeeling District; Bhutan in its entirety; and the northeastern Indian state of Arunachal Pradesh. By many measure of biodiversity, the eastern Himalaya region stands out as being globally important. It has been included among earth s biodiversity hotspot (Myers et al., 2000) and includes several Global 200 ecoregions (Olson & Dinerstein, 1998), two Endemic Birds Areas (Shattersfield et al., 1998), and several centres for plants diversity (WWF/IUCN 1

2 1995). Several factors contribute to the exceptional biodiversity of the eastern Himalaya. First, the eastern Himalaya has multiple biogeographic origins. Its location at the juncture of the two continental plates places it in an ecotone represented by flora and fauna from both. Second, there is considerable climatic variability associated with the topography and vast reaches of the mountains. The eastern Himalaya is more nearer to the Tropic of Cancer in latitude and is geographically closer to the Bay of Bengal and to the monsoon winds, as a result of which it is more humid and exhibits higher primary productivity. The steeper terrain, narrow extent and fragmentation and higher rainfall make it more fragile and hence more prone to degradation. Thunderstorms occur frequently in the eastern Himalaya during the premonsoon season from March to May and precipitation is heavy, increasing from March to May with the advent of the hot season. The eastern Himalaya has a prolonged monsoon season from June to September and little precipitation occurs in the winter. The general climatic conditions in the eastern Himalaya are semi-oceanic but becoming increasingly continental in the western parts of the Himalaya (Miller, 1987). The region receives more moisture from the summer monsoon and the average precipitation is 20% in winter and 80% in summer, resulting in humid conditions. Due to heavy rainfall, the treeline is higher at 4500m and the krummholtz and the alpine scrub are also more wide-ranging in the eastern Himalaya. The permanent snow line is at 5,500m in the eastern Himalaya and there are still many virgin primary forest patches throughout the Himalayan region with higher level of endemism. Out of 98% of the Indian species of the Rhododendron found in the Himalaya, 72% are found in Sikkim Himalaya and this region accounts 50% of the plant population found in India. Of the 372 mammalian species in India as many as 241 species (65%) are recorded in the Himalaya, of which as many as 29 (37%) of species listed under Schedule I of the Wildlife (Protection) Act (1972) occur in the Himalayas (Ghosh, 1996). The eastern Himalayan habitat supports a high diversity of birds and is one of the most diverse regions in the orient (Crosby, 1996). This region is identified as the Endemic Bird Area (Birdlife International, 2001), which supports 22 restricted-range birds species of which 19 are endemic to the eastern Himalaya (Stattersfield et al.,1998; Jathar & Rahmani, 2006; IUCN, 2009). 2

3 1.1. Sikkim The State of Sikkim is spread below the world s third highest mountain Mt. Khangchendzonga (8,585m) revered by Sikkimese as their protective deity. Sikkim with an area of 7,096 km 2 extends about 114 km from north to south and 64 km from east to west and is separated by Tibetan Plateau in the North, Chumbi valley of Tibet and the Kingdom of Bhutan in the east, Darjeeling district of West Bengal in the south and Nepal in the west. In this land of vast altitudinal variation (ca. 300m - 8,586m) within a very short distance, elevation has played a major role in fashioning the various eco-regions. This is evident from the presence of the sub-tropical sal forest to temperate broad-leaved forest to temperate conifer forest to alpine grass beyond which lies the trans-himalayan habitat. According to Rodgers et al., (2000), Sikkim is classified as a part of the Biogeographic province 2C (Central Himalaya), which in India includes the Darjeeling district of West Bengal with Temperate-Broadleaf biome, with the north of Sikkim as Biogeographic province 1C (Trans- Himalaya-Tibetan plateau) with biota of Palaearctic affinity. The latter area is high-altitude cold desert in the rain-shadow of the main Himalayan range with typical flora and fauna. Sikkim is endowed with rich natural resources and biodiversity elements which are of global significance. This region is listed among the world s most critical centres for biodiversity and endemic species with 150 species of mammals, 550 species of birds, 650 species of butterflies and moths, 33 species of reptiles, 16 species of amphibians, 48 species of fishes, 4500 species of flowering plants, 36 species of rhododendrons, nine species of conifer, 450 species of trees, 480 species of orchids, 362 species of ferns and allies and 17 species of wild edible plants Khangchendzonga Biosphere Reserve The Khangchendzonga Biosphere Reserve is the highest altitude wildlife protected area in Sikkim that spans across the north, west and south Sikkim districts. It lies entirely along the Sikkim-Nepal border and includes the Khnagchendzonga Range from the South Lhonak Glacier in Trans-Himalaya Sikkim down to Barsey Rhododendron Sanctuary in the south Sikkim. To conserve and manage the high altitude ecosystem of the state, Khangchendzonga National Park (NP) was created in 1977 with an area of 880 km 2, which was later expanded to 1,784 km 2. The conservation and management efforts in Khangchendzonga NP was further strengthened by addition of 836 km 2 buffer zones to the 3

4 NP to constitute the Khangchendzonga Biosphere Reserve (BR) in 2000 (Sharma & Lachungpa, 2002). The recent notification (204/KNP-KBR/WL/Forest/2009 dated ) added transition zone of km 2 covering north, west and south district of Sikkim making the total area of Khangchendzonga Biosphere Reserve as 2, km 2. This area holds an array of wildlife habitats that supports rich biodiversity and forms an integral part of the people living in the region and provides life-support systems for several million people living in the hills and plains south of the region The Himalaya and its Pheasants Pheasants are the most charismatic and striking of all the fauna found in the Himalayan landscape. Their high endemism and brightly coloured plumage makes them the most distinctive bird family of the Himalaya (Ali, 1981). Their role as prey-base for carnivorous birds and mammals provide a significant identity in the functioning of the high altitude ecosystem (Johnsgard, 1986). Of the 51 species of pheasants (16 genera), 20 (39%) are endemic to the Himalaya. The Indian Himalaya is home to 16 species of pheasant that form 94% of the total pheasant species (17) found in India. Five of the six species of pheasants that are threatened in India are found in Himalaya (Sathyakumar & Sivakumar, 2007). Along their distribution range pheasants are found in diverse habitats like lowlands tropical forests to temperate coniferous forest, subalpine scrub, alpine meadows, montane grass scrub, and broad-leaved evergreen forests (Table 1.1) Pheasants, along with other game birds such as partridges and quails, have long been associated with social and religious status of people living in Asia and Europe. Many of the pheasants have been kept in captivity because of their spectacular plumage patterns (males) and have also been considered as ornamental birds. Use of feathers is considered significant in the rituals and local ceremonies among the people across Asia (Ramesh, 2003). Interests of several of these factors have led to the removal of wild population from their native range. Scanty ecological information and loss of their potential habitats due to human encroachment and development have led to the depletion of pheasant population in most part of their distribution range. Winter season in this region plays a major role in their survival and also determines the brood size of individual birds. Their heavy built plumage and large body size are adaptation to survive in the harsh climatic condition in high altitudes. 4

5 Table 1.1. Ecological distribution of the Pheasants found in the Indian Himalaya (Ramesh, 2003) No. Species a Vegetation types b Altudinal range(m) b 1. Blood pheasant Temperate fir and sub-alpine Ithaginis cruentus rhododendron, birch and juniper Hardwicke 1822 patches 2. Western Tragopan Tragopan melanocephalus Gray Satyr tragopan Tragopan satyra Linn Blyth s tragopan Tragopan blythii Jerdon Temminck s tragopan Tragopan temminckii Gray Koklass pheasant Pucrasia macrolopha Lesson Himalayan monal Lophophorus sclateri Jerdon Sclater s monal Lophophorus sclateri Jerdon Red junglefowl Gallus gallus Linn Kalij pheasant Lophura leucomelanos Latham Tibetan earedpheasant Crossoptilon harmani Elwes 12. Cheer pheasant Catreus wallachi Haedwicke Hume s pheasant Syrmaticus humiae Hume Grey peacock pheasant Upper temperate conifer and subalpine oak forests with dense under growth and bamboo patches Temperate conifer and sub-alpine oak forests with dense under growth and bamboo patches Moist evergreen broad-leaved forests with thick under storey of ringal bamboo Dense undergrowth in damp, evergreen broadleaf and sub-alpine forests Temperate broadleaf, conifer and sub-alpine oak and alpine scrub and meadows Upper temperate conifer forests, sub-alpine oak and alpine scrub and meadows Upper temperate fir forest and alpine scrub Tropical and subtropical and secondary forests with dense under growth, habitations Tropical and subtropical and secondary forests with dense under growth, habitations Upper temperate, sub-alpine forests and alpine scrub Rocky slopes with bushes, long grasses, nullas and open oak and pine forest Rocky slopes with bushes, long grasses and open oak and pine forest Tropical moist, broad-leaved evergreen and semi ever green forest 5 3,200-4,400 (1,500 in winter) 2,400-3,600 (2,000 in winter) 2,590-3,800 (2,000 in winter) Status c V V V 1,800-3,500 E 2,100-3,600 S 2,100-3,300 S 2,400-4,500 (2,000 in winters) S 3,000-4,000 E Up to 2,000** S 245-3,050 S 2,800-4,600 E* 1,500-3,050 V 1,200-3,000 E Up to 1,200 S

6 Polypectron bicalcaratum Linnaeus Indian peafowl Pavo cristatus Linnaeus 1758 Deciduous forests, agricultural lands, habitations Up to 1,800 a Johnsgard (1986); b Grimmett, et al., (1998) c McGowan and Garson (1995) (V = Vulnerable, E = Endangered, S = Safe,? = Not known * - no recent records from India) ** (Sathyakumar et al., 2012). S Galliformes found in Khangchendzonga Biosphere Reserve Despite the Sikkim State bird being a galliformes (Blood pheasant), till date, there has been no systematic survey or population estimation of galliformes of Sikkim. Seven species of galliformes are found in Khangchendzonga BR out of which six are present in the study area (Table 1.2, Plate 1.1 & Figure 1.1). The information has been compiled from Ali and Ripley (1983), Johnsgard (1988, 1986), Grimmett, Inskipp and Inskipp (1998), Sathyakumar et al., 2007). Table 1.2: Galliformes of Khangchendzonga Biosphere Reserve COMMON NAME SCIENTIFIC NAME LOCAL NAME CONSERVATION STATUS IUCN IWPA Schedule Blood Pheasant Ithaginis cruentus Chilimay others 1 Satyr Tragoopan Tragopan satyra Mudal NT* I Himalayan Monal Lophophorus impejanus Daphe others 1 Hill Partridge Arborophila torqueola Pur-ra others IV Snow Partridge Lerwa lerwa Lerwa others IV Black-breasted Kalij Lophura leucomelanos lathami Kalij others 1 *NT-Near Threatened 6

7 Plate 1.1. Camera-trap photographs of some galliformes present in Khangchendzonga BR (1) himalayan monal (2) blood pheasant (3) snow partridge (4) satyr tragopan (5) kalij (6) hill partridge 7

8 Figure 1.1 Distribution map (in yellow shaded region) of galliformes in the Greater Himalaya (Source: Rationale for the study Galliformes especially pheasants have been associated with social and religious status of people living in Asia and Europe. They are killed for food, feathers and entertainment and they also form an important source of meat and at the same time considered as an integral part of the spiritual beliefs for many tribes in the states of northeast India. Pheasant hunting is a very popular game in Europe and America. As such, many pheasants are likely to become extinct within the next 100 years, if exploitation and habitat destruction continues (Ramesh, 2003). Apart from this, galliformes serve as an indicator of the health of a forest. Over 10 major research studies and some surveys (Chettri, 2000a; Singh et al., 2002; Krishna & Sharma, 2002; Krishna et al., 2002; Maity & Chauhan, 2002; Chauhan et al., 2003; Singh, 2005; Chettri et al.,2006; Tambe 2007) have been carried out in Khangchendzonga NP and 8

9 BR but all focusing on vegetation, habitats, birds, insect fauna and social studies. However, there is no information on distribution, relative abundance, and ecology of galliformes (prey for carnivores) of Khangchendzonga BR. 9