Silent Valley National Park is a national park with a core zone of 236.74 square kilometres (91 sq mi) (making it the largest national park in Kerala). It is located in the Nilgiri Hills, within the Palakkad District of Kerala, South India. This region was explored in 1847 by the botanist Robert Wight, and is a setting for the epic Mahabharatha.
This park is one of the last undisturbed tracts of South Western Ghats mountain rain forests and tropical moist evergreen forest in India. Contiguous with the proposed Karimpuzha National Park (225 km2) to the north and Mukurthi National Park (78.46 km2) to the north-east, it is the core of the Nilgiri International Biosphere Reserve (1,455.4 km2), and is part of The Nilgiri Sub-Cluster (6,000+ km2), Western Ghats World Heritage Site, recognised by UNESCO in 2007.
History:
The Silent Valley region is locally known as "Sairandhrivanam", which in Malayalam means Sairandhri's Forest. Sairandhri is Draupadi, the wife of the Pandavas in the epic Mahabharatha, who disguised herself as Sairandhri, the maid of a queen named Sudeshna, while her family was in exile. The Pandavas, deprived of their kingdom, set out on a 13-year exile. They wandered south, into what is now Kerala, until one day they came upon a magical valley where rolling grasslands met wooded ravines, a deep green river bubbled its course through impenetrable forest, where at dawn and twilight the tiger and elephant would drink together at the water's edge, where all was harmonious and man unknown. Beside that river, in a cave on a hill slope, the Pandavas halted.
Environmental concerns:
Silent Valley is home to the largest population of lion-tailed macaques, an endangered species of primate. Public controversy over their habitat led to the establishment of Silent Valley National Park.
In 1973 the valley became the focus of "Save Silent Valley", India's fiercest environmental movement of the decade, when the Kerala State Electricity Board decided to implement the Silent Valley Hydro-Electric Project (SVHEP) centered on a dam across the Kunthipuzha River. The resulting reservoir would flood 8.3 km2 of virgin rainforest and threaten the lion-tailed macaque. In 1976 the Kerala State Electricity Board announced plans to begin dam construction and the issue was brought to public attention. Romulus Whitaker, founder of the Madras Snake Park and the Madras Crocodile Bank, was probably the first person to draw public attention to the small and remote area.
Geography:
Hanging Bridge across the Kuntipuzha River – Silent Valley National Park (SVNP)
Silent Valley is rectangular, twelve kilometres from north to south and seven from east to west. Located between 11°03' to 11°13' N (latitude) and 76°21' to 76°35' E (longitude) it is separated from the eastern and northern high altitude plateaus of the (Nilgiris Mountains) by high continuous ridges including Sispara Peak (2,206 m) at the north end of the park. The park gradually slopes southward down to the Palakkad plains and to the west it is bounded by irregular ridges. The altitude varies from 658 m to 2328 m at Anginda Peak.
Rivers:
The Kuntipuzha River drains the entire 15 km length of the park from north to south into the Bharathapuzha River. Kuntipuzha River divides the park into a narrow eastern sector of width 2 kilometers and a wide western sector of 5 kilometers. The river is characterized by its crystal clear water and perennial nature.
Climate:
Silent Valley gets copious amounts of rainfall during the monsoons, but the actual amount varies within the region due to the varied topography. In general, rainfall is higher at higher altitudes and decreases from the west to the east due to the rain shadow effect. Eighty per cent of the rainfall occurs during the south-west monsoon between June and September.
The mean annual temperature is 20.2 °C. The hottest months are April and May when the mean temperature is 23 °C and the coolest months are January and February when the mean temperature is 18 °C. Because of the high rainfall, the relative humidity is consistently high (above 95%) between June and December.
Tribes:
There is no record of the valley ever having been settled, but the Mudugar and Irula tribal people are indigenous to the area and do live in the adjacent valley of Attappady Reserved Forest. Also, the Kurumbar people occupy the highest range outside the park bordering on the Nilgiris.
Fauna and flora:
The valley areas of the park are in a Tropical and subtropical moist broadleaf forests Ecoregion. Hilly areas above 1,000 m are in the South Western Ghats montane rain forests region. Above 1,500 m, the evergreen forests begin to give way to stunted forests, called sholas, interspersed with open grassland, both of which are of interest to ecologists as the rich biodiversity here has never been disturbed by human settlements. Several threatened species are endemic here. New plant and animal species are often discovered here.
Birds:
Birdlife International lists 16 bird species in Silent Valley as threatened or restricted:- Nilgiri wood-pigeon, Malabar parakeet, Malabar grey hornbill, white-bellied treepie, grey-headed bulbul, broad-tailed grassbird, rufous babbler, Wynaad laughing thrush, Nilgiri laughing thrush, Nilgiri blue robin, black-and-rufous flycatcher, Nilgiri flycatcher, white-bellied blue-flycatcher, crimson-backed sunbird and Nilgiri pipit.
Rare bird species found here include the Ceylon frogmouth and great Indian hornbill. The 2006 winter bird survey discovered the long-legged buzzard, a new species of raptor at Sispara, the park's highest peak. The survey found 10 endangered species recorded in the IUCN Red List including the red winged crested cuckoo,
Mammals:
There are at least 34 species of mammals at Silent Valley including the threatened lion-tailed macaque, Niligiri langur, Malabar giant squirrel, Nilgiri tahr, Peshwa’s bat (Myotis peshwa) and hairy-winged bat. There are nine species of bats, rats and mice.
The tiger, leopard (panther), leopard cat, jungle cat, fishing cat, common palm civet, small Indian civet, brown palm civet, ruddy mongoose, stripe-necked mongoose, dhole, clawless otter, sloth bear, small Travancore flying squirrel, Indian pangolin (scaly anteater), porcupine, wild boar, sambar, spotted deer, barking deer, mouse deer, elephant and gaur also live here.
Insects:
There are at least 730 identified species of insects in the park. The maximum number of species belong to the orders Lepidoptera and Coleoptera. Many unclassified species have been collected and there is a need for further studies.
33 species of crickets and grasshoppers have been recorded of which one was new. 41 species of true bugs (eight new)have been recorded. 128 species of beetles including 10 new species have been recorded.
Over 128 species of butterflies and 400 species of moths live here. A 1993 study found butterflies belonging to 9 families. The families Nymphalidae and Papilionidae contained the maximum number of species. 13 species were endemic to South India, including 5 species having protected status.Seven species of butterflies]] were observed migrating in a mixed swarm of thousands of butterflies towards the Silent Valley National Park.
At least 500 species of earthworms and leeches have also been identified in the park.
Flora:
The flora of the valley include about a 1000 species of flowering plants, 108 species of orchids, 100 ferns and fern allies, 200 liverworts, 75 lichens and about 200 algae. A majority of these plants are endemic to the Western Ghats.
Trees:
Occurrence of lion-tailed macaque is dependent on the flowering of Cullenia exarillata in the forest.
Six distinct tree associations[clarification needed] have been described in the valley. Three are restricted to the southern sector:
Cullenia exarillata and Palaquium ellipticum
Palaquium ellipticum and Mesua ferrea (Indian rose chestnut)
Mesua ferrea and Calophyllum elatum
The remainder are confined to the central and northern parts of the park:
Genetic resources:
Throughout human history about 10% of the genetic stock found in the wild has been bred into palatable and higher yielding cereals, fruits and vegetables. Future food security depends on the preservation of the remaining 90% of the stock through protection of high biodiversity habitats like Silent valley.
Also, genetic evaluation of plant growth promoting Rhizobacteria obtained from Silent Valley indicated that strain, IISR 331, could increase the growth of black pepper cuttings by 228% and showed 82.7% inhibition of the common plant wilting disease Phytopthora capsici in laboratory tests (in vitro)
