Silent Valley National Park

Coordinates: 11°08′N 76°28′E / 11.133°N 76.467°E / 11.133; 76.467
From Wikipedia, the free encyclopedia

Silent Valley National Park
Malayalam: സൈലന്‍റ് വാലീ നാഷണല്‍ പാര്‍ക്ക്
The Nilgiri Mountains as seen from Silent Valley National Park
Map showing the location of Silent Valley National Park
Map showing the location of Silent Valley National Park
Location in Kerala, India
Nearest cityMannarkkad
Coordinates11°08′N 76°28′E / 11.133°N 76.467°E / 11.133; 76.467
Area89.52 km2 (34.56 sq mi)
Established26 December 1984
Governing bodyDepartment of Forests and Wildlife (Kerala)

Silent Valley National Park is a national park in Kerala, India. It is located in the Nilgiri hills and has a core area of 89.52 km2 (34.56 sq mi). It is surrounded by a buffer zone of 148 km2 (57 sq mi). This national park has some rare species of flora and fauna. Silent Valley National Park was explored in 1847 by the botanist Robert Wight.[2] It is located in the border of Mannarkkad Taluk of Palakkad district, Nilambur Taluk of Malappuram district, Kerala, and Nilgiris district of Tamil Nadu.

It is located in the rich biodiversity of Nilgiri Biosphere Reserve. The Karimpuzha Wildlife Sanctuary, New Amarambalam Reserved Forest, Nedumkayam Rainforest in Nilambur Taluk of Malappuram district, Attappadi Reserved Forest in Mannarkkad Taluk of Palakkad district, and Mukurthi National Park of Nilgiris district are located around Silent Valley National Park. Mukurthi peak, the fifth-highest peak in South India, and Anginda peak are also located in its vicinity. The Bhavani River, a tributary of the Kaveri River, and Kunthipuzha River, a tributary of Bharathappuzha river, originate in the vicinity of Silent Valley. The Kadalundi River also originates in Silent Valley National Park.

The national 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 (87 sq mi)) to the north and Mukurthi National Park (78.46 km2) to the north-east, it is the core of the Nilgiri 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.[3]

Plans for a hydroelectric project that threatened the park's biodiversity stimulated an environmentalist social movement in the 1970s, known as the Save Silent Valley movement, which resulted in cancelling the project and creating the park in 1980. The visitors' centre for the park is at Sairandhri.


Map of Nilgiris Biosphere Reserve, showing Silent Valley National Park in relation to multiple contiguous protected areas

The first Western investigation of the watersheds of the Silent Valley area was in 1857 by the botanist Robert Wight.[2] The British named the area Silent Valley because of a perceived absence of noisy cicadas. Another story attributes the name to the anglicisation of Sairandhri. A third story refers to the presence of many lion-tailed macaques Macaca silenus.[4] In 1914, the forest of the Silent Valley area was declared a reserve forest. Between 1927 and 1976, portions of the Silent Valley forest area were subjected to forestry operations. In 1928, the location on the Kunthipuzha River at Sairandhri was identified as an ideal site for electricity generation, and in 1958 a study and survey of the area was conducted and a hydroelectric project of 120 MV costing Rs. 17 crore was proposed by the Kerala State Electricity Board.[5]

Environmental concerns[edit]

Lion-tailed macaque

Silent Valley is home to the largest population of lion-tailed macaques, an endangered species of primate. Public concern over threats to 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.[6]

On 7 September 1985 the Silent Valley National Park was formally inaugurated and a memorial at Sairandhri to Indira Gandhi was unveiled by Rajiv Gandhi, her son and the next prime minister. On 1 September 1986 Silent Valley National Park was designated as the core area of the Nilgiri Biosphere Reserve. Since then, a long-term conservation effort has been undertaken to preserve the Silent Valley ecosystem.[5]

In 2001 a new hydro project was proposed and the "Man vs. Monkey debate" was revived. The proposed site of the dam (64.5 m high and 275 m long) is just 3.5 km downstream of the old dam site at Sairandhiri, 500 m outside the National Park boundary.[7] The Kerala Minister for Electricity called The Pathrakkadavu dam (PHEP) an "eco-friendly alternative" to the old Silent Valley project. The claim was that the submergence area of the PHEP would be a negligible .041 km2 compared to 8.30 km2 submergence of the 1970s (SVHEP).[8] From January to May 2003, a rapid Environmental Impact Assessment (EIA) was carried out. On 15 November, Minister for Forest Binoy Viswam said that the proposed buffer zone for Silent Valley would be declared soon.[9]

On 21 February 2007 ex-Chief Minister A. K. Antony told reporters after a cabinet meeting that "when the Silent Valley proposal was dropped, the centre had promised to give clearance to the Pooyamkutty project. This promise, however, had not been honoured. The Kerala government has not taken any decision on reviving the Silent Valley Hydel Project".[10]

On 18 April 2007, Kerala Chief Minister V S Achuthanandan and his cabinet approved the Pathrakkadavu Hydro-electric project and sent it to the Union Government for environmental approval.[11][12]

Map of Silent Valley NP

Buffer zone[edit]

Territorial forests located around the national park have been subject to a working-plan to accomplish revenue oriented objectives such as extraction of bamboo and reed which affect the long-term conservation of the park.[citation needed] In addition, illegal activities such as ganja (Cannabis sativa) cultivation has caused habitat degradation.[13]

On 21 November 2009, Union Minister of Forest and Environment Jairam Ramesh and Kerala Forest Minister Binoy Viswam declared, while inaugurating the silver jubilee celebration of Silent Valley National Park in Palakkad, that the buffer zone of the Park would be made an integral part of it in order to ensure better protection of the area.[14]

On 6 June 2007 the Kerala cabinet approved the buffer zone proposal. The new 147.22 km2 zone will include 80.75 km2 taken from Attapady Forest Range, 27.09 km2 from Mannarkkad Forest Range and 39.38 km2 from Kalikavu Forest Range and consolidated to form a new range, Bhavani Forest Range, of 94 km2 and 54 km2 would be brought under the existing Silent Valley Range of the National Park. The Cabinet also sanctioned 35 staff to protect the area and two new forest stations in Bhavani range at Anavai and Thudukki. Forest Minister Benoy Viswom said "the zone would have reserve forest status and tribals in the area would not be affected. The decision reaffirmed the commitment of the LDF Government to protection of environment. The zone is a necessity, not just of the State but also of the nation."[15]

The proposal was then sent to Kerala Minister for Electricity, A. K. Balan, who has voiced the need for setting up the Pathrakadavu hydroelectric project in the proposed southwest buffer zone of the National Park, the Thenkara Range of the Mannarkkad Forest Division. As of 9 May 2007 Balan has not given his opinion on the buffer zone proposal.[16]

In August 2006, the new Minister for Forests, Benoy Viswam, approved a proposal from the Conservator of Forests for a 148 km2 buffer zone around the core area of the park. The proposal says: "It is felt absolutely essential that an effective buffer of forests should be immediately formed around the national park in order to save the world famous Silent Valley National Park from all potential dangers. This can only be achieved by bringing the management of Silent Valley National Park as well as the proposed buffer zone under one management umbrella to insulate the park from all possible dangers." The proposed buffer zone will have 94 km2 in Attappady Reserve Forest east of the Kunthipuzha and 54 km2 taken from the Mannarkaad range and Nilambur south division west of the river.

In January 2006, the former Kerala Minister for Forest and Environment, A. Sujanapal, said the Government would consider the demand for a 600 km2 buffer zone for Silent Valley National Park made by Bharathapuzha Protection Committee, Malampuzha Protection Committee, One Earth One Life and Jana Jagratha. A buffer zone proposal was made in the 1986 park management plan but not implemented.[17]

In 1979, M.S. Swaminathan, then Secretary to the Department of Agriculture, visited the Silent Valley area and suggested that 389.52 km2 including the Silent Valley (89.52 km2), New Amarambalam (80 km2), Attappadi (120 km2) in Kerala and Kunda in Coimbatore (100 km2) reserve forests, should be developed into a National Rainforest Biosphere Reserve.[18]

On 27 October 2020 draft notification was made by Govt. of India for the area around the National park declaring it as eco sensitive zone.[19]


Hanging Bridge across the Kuntipuzha River – Silent Valley National Park (SVNP)
Silent Valley National Park
Topography 1:250,000., 1959'.

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, but most of the park lies within the altitude range of 880 m to 1200 m. Soils are blackish and slightly acidic in evergreen forests where there is good accumulation of organic matter. The underlying rock in the area is granite with schists and gneiss, which give rise to the loamy laterite soils on slopes.[20]


The Kunthipuzha River drains the entire 15 km length of the park from north to south into the Bharathapuzha River. Kunthipuzha 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. The main tributaries of the river, Kunthancholapuzha, Karingathodu, Madrimaranthodu, Valiaparathodu and Kummaathanthodu originate on the upper slopes of the eastern side of the valley. The river is uniformly shallow, with no flood plains or meanders. Its bed falls from 1,861 m to 900 m over a distance of 12 km, the last 8 km being particularly level with a fall of only 60 m. Kunthipuzha is one of the less torrential rivers of the Western Ghats, with a pesticide-free catchment area.[21]


Silent Valley from JPL Map server.

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 park also receives a significant amount of rainfall during the north-east monsoon between October and November.[22]

The park being completely enclosed within a ring of hills, has its own micro-climate and probably receives some convectional rainfall, in addition to rain from the two monsoons. In the remaining months, condensation on vegetation of mist shrouding the valley is estimated to yield 15 per cent of the total water generated in the rainforest.[23]

In 2006, the Walakkad area of the park received the highest ever annual rainfall of 9,569.6 mm. In 2000, the figure was 7,788 mm; in 2001, 8,351.9 mm; in 2004, 8465.3 mm; and in 2005, 9,347.8 mm. The annual rainfall received in the valley (at Sairandhri?) was 7,788.8 mm in 2000; 8,361.9 mm in 2001. In 2002, 4,262.5 mm; in 2003, 3,499.65 mm; in 2004, 6,521.27 mm, in 2005, 6,919.38 mm; in 2006, 6,845.05 mm; in 2007, 6,009.35 mm; and in 2008 it was 4386.5 mm. The figure till October 2009 was 5,477.4 mm. Average annual rainfall in the park between 2000 and 2008 was thus 6,066 mm.[14]

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.[21]

Indigenous people[edit]

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.[24][25] Also, the Kurumbar people live in the highest range outside the park bordering on the Nilgiris.[26]

Many of the Mudugar, Irula and Kurumbar now work as day labourers and porters. 16 out of 21 tribal colonies in the Attappady range cultivate marijuana. Many Mudugar are in abject poverty and easily recruited by the so-called ganja mafia. In 2006, it was planned to employ 50 additional men from the 21 tribal settlements as forest guards.[13]

Flora and fauna[edit]

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.[21]



A Nilgiri wood-pigeon

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 laughingthrush, Nilgiri laughing thrush, Nilgiri blue robin, black-and-rufous flycatcher, Nilgiri flycatcher, white-bellied blue-flycatcher, crimson-backed sunbird and Nilgiri pipit.[27]

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, Malabar pied hornbill and pale harrier. The area is home to 15 endemic species including the black-and-orange flycatcher. It recorded 138 species of birds including 17 species that were newly observed in the Silent Valley area. The most abundant bird was the Square-tailed bulbul.[28]


Nilgiri langur

There are at least 34 species of mammals at Silent Valley including the threatened lion-tailed macaque, Nilgiri langur, Malabar giant squirrel, Nilgiri tahr, Peshwa's bat (Myotis peshwa) and hairy-winged bat. There are nine species of bats, rats and mice.[29]

Distribution and demography of all diurnal primates were studied in Silent Valley National Park and adjacent areas for a period of three years from 1993 to 1996. Fourteen troops of lion-tailed macaque, eighty-five troops of Nilgiri langur, fifteen troops of bonnet macaque and seven troops of Hanuman langur were observed. Of these, the Nilgiri langur was randomly distributed, whereas the lion-tailed macaque troops were confined to the southern sector of the Park. Bonnet macaques and Hanuman langurs were occasional visitors. The Silent Valley forest remains one of the most undisturbed viable habitats left for the endemic and endangered primates lion-tailed macaque and Nilgiri langur.[30]

Tiger, leopard, leopard cat, jungle 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.[citation needed]


Vestalis submontana, endemic to Western Ghats

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.[31]

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.[32]

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.[33] Seven species of butterflies were observed migrating in a mixed swarm of thousands of butterflies towards the Silent Valley National Park. In one instance an observer noted several birds attempting to catch these butterflies.[34]

A survey jointly conducted by Indian Dragonfly Society and the Forest and Wildlife Department in September 2018 in the buffer zone of the Silent Valley National Park found 82 species of odonata. The species found include Indosticta deccanensis, Burmagomphus laidlawi, Microgomphus souteri, Onychogomphus nilgiriensis, Euphaea dispar, Idionyx travancorensis, Megalogomphus hannyngtoni and Lestes dorothea.[35]


Silent Valley Bush Frog, Raorchestes silentvalley

At least 500 species of earthworms and leeches have also been identified in the park.[29]

The Silent Valley Bush Frog, Raorchestes silentvalley, first described in 2016, is named after the park.[36]


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.[37]

Senecio neelgherryanus in Silent Valley
Graphium agamemnon
Tailed jay nectoring on a daisy

Flowering plants[edit]

Angiosperm flora currently identified here include 966 species belonging to 134 families and 599 genera. There are 701 Dicotyledons distributed among 113 families and 420 genera. There are 265 Monocotyledons here distributed among 21 families and 139 genera. Families best represented are the Orchids with 108 species including the rare, endemic and highly endangered orchids Ipsea malabarica, Bulbophyllum silentvalliensis and Eria tiagii, Grasses (56), Legumes (55), Rubiaceae (49) and Asters (45). There are many rare, endemic and economically valuable species, such as cardamom Ellettaria cardamomum, black pepper Piper nigrum, yams Dioscorea spp., beans Phaseolus sp., a pest-resistant strain of rice Oryza Pittambi, and 110 plant species of importance in Ayurvedic medicine.[38] Seven new plant species have been recorded from Silent Valley, including in 1996, Impatiens sivarajanii, a new species of Balsaminaceae.[39]


Occurrence of lion-tailed macaque is dependent on the flowering of Cullenia exarillata in the forest.[40]

Six distinct tree associations[clarification needed] have been described in the valley. Three are restricted to the southern sector:

  1. Cullenia exarillata and Palaquium ellipticum
  2. Palaquium ellipticum and Mesua ferrea (Indian rose chestnut)
  3. Mesua ferrea and Calophyllum elatum

The remainder are confined to the central and northern parts of the park:

  1. Palaquium ellipticum and Poeciloneuron indicum
  2. Calophyllum elatum and Ochlandra species
  3. Poeciloneuron indicum and Ochlandra species[41]

A study of natural regeneration of 12 important tree species of Silent Valley tropical rain forests showed good natural regeneration of all 12 species. The species studied were Palaquium ellipticum, Cullenia exarillata, Poeciloneuron indicum, Myristica dactyloides, Elaeocarpus glandulosus, Litsea floribunda, Mesua nagassarium, Cinnamomum malabatrum, Agrostistachys meeboldii, Calophyllum polyanthum, Garcinia morella and Actinodaphne campanulata.[42]

In 2001 selective felling of three trees per acre led to the cutting of 48,000 m3 of timber from about 20 km2.[43]

Genetic resources[edit]

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.[44]

The National Bureau of Plant Genetic Resources of ICAR (India), Plant Exploration and Collection Division[45] has identified Silent Valley as high in bio-diversity and an important Gene Pool resource for Recombinant DNA innovations. An important example of use of wild germplasm is gene selection from the wild varieties of rice Oryza nivara (Central India) and Oryza Pittambi found in Silent Valley for the traits of broad spectrum disease resistance in high yielding hybrid rice varieties including IR-36, which are responsible for much of the Green Revolution throughout Asia.[46]

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).[47]


Forest fire[edit]

Fire is one of the major threats facing forests in Kerala. People engaged in grazing livestock often burn an area to get fresh grass shoots for their cattle, especially during dry season when fire danger is greatest. Also, illicit activities like ganja cultivation, poaching, tree felling, non timber forest products (NTFP) collection and very often careless tourists and pilgrims are responsible for big forest fires.[48]

Cannabis cultivation[edit]

Silent Valley is home to some of India's largest illegal plantations of cannabis.[49] Cannabis is one of the traditional plantations in these forests and there are people who depend on 'Ganja economy' for a livelihood.[50] Tribes like Irula, Muduga and Kurumba (particularly the last one) have always grown cannabis in their history.[51] The seedless variety of cannabis cultivated in Silent Valley is known as Sairandhri and is renowned internationally for its quality.[52]

According to former additional chief secretary Madhava Menon, the cannabis cultivated here is one of the best in the world and is sold worldwide.[51] The cannabis mafia has cut hundreds of acres of evergreen tropical forest in the Attappady Hills, including Silent Valley buffer zones, for illegal cultivation of the cash crop. The Forest Department had an ambitious plan to root out ganja cultivation from the Attappady forests by April 2006.[13]

Maoist Presence[edit]

The ticket counter of the Silent Valley National Park at Mukkali was attacked by a group of Maoists in December, 2014. A big contingent of special police has been deployed there since then, but the growing influence of Maoist groups in tribal east Kerala is of grave concern.[53]


  1. ^ Protected Planet (2018). "Silent Valley National Park". United Nations Environment World Conservation Monitoring Centre. Archived from the original on 16 January 2019. Retrieved 16 January 2019.
  2. ^ a b Kumar, N. S. (2004). "Silent Valley: Trekking through the Amazon of India" (PDF). Corporate House Journal of Indian Oil Corporation Limited. XXXXI: 15–16. Archived from the original (PDF) on 28 September 2007. Retrieved 2 July 2007.
  3. ^ "Research: UNESCO, World Heritage sites, Tentative lists, Western Ghats sub cluster, Niligiris". UNESCO. 2007. Retrieved 18 October 2007.
  4. ^ Krishnan, V. (2007). "Into the Jungle". Sunday Express. Archived from the original on 29 September 2007. Retrieved 3 July 2007.
  5. ^ a b Gledhill, Laurence (1996). "Silent Valley - A masterplan for The Indian Ex-situ Population of Lion-tailed Macaques, Macaca silenus and A Historical Profile of Habitat Conservation in Kerala, India". Newsletter for the Old World Monkey Taxon Advisory Group. 3 (2). American Zoo and Aquarium Association. Retrieved 18 October 2007. Reprinted from the 1995 Proceedings of the Joint Conference of the American Association of Zoo Veterinarians, the Wildlife Disease Association, and the American Association of Wildlife Veterinarians
  6. ^ "Storm over Silent Valley, A Peoples Movement Saves A Valley". Ministry of Environment and Forests (India). Retrieved 18 October 2007.
  7. ^ Kumar, K.G. (2004). "Silent Valley redux?". The Hindu Business Line. Retrieved 3 October 2007.
  8. ^ Surendranath, C.; Suchitra, M. (2004). "New whispers in Silent Valley". The Hindu. Archived from the original on 15 January 2005. Retrieved 3 October 2007.
  9. ^ "Kerala minister of Forests: "Proposed buffer Zone to be declared soon". The Hindu. 2006. Archived from the original on 28 October 2007. Retrieved 3 October 2007.
  10. ^ "No decision yet on Silent Valley: Antony". Times of India. 23 February 2007. Archived from the original on 28 February 2008. Retrieved 18 October 2007.
  11. ^ "Green Marxist succumbs to 'Power' needs". 19 April 2007. Archived from the original on 27 September 2007. Retrieved 5 October 2007.
  12. ^ Suchitra, M. (2007). "Kerala clears Pathrakkadavu hydroelectric project near national park". Down to Earth. Archived from the original on 28 September 2007. Retrieved 12 June 2007.
  13. ^ a b c Prabhakaran, G. (2006). "Plan afoot to uproot ganja from Silent Valley". The Hindu. Archived from the original on 1 October 2007. Retrieved 3 March 2007.
  14. ^ a b Prabhakaran, G. (2009). "A rainforest's saga of survival". The Hindu, Op-Ed. Chennai: Kasturi and Sons Ltd. Retrieved 27 December 2009.
  15. ^ "Cabinet approves buffer zone for Silent Valley". The Hindu. 2007. Archived from the original on 17 September 2007. Retrieved 8 June 2007.
  16. ^ Prabhakaran, G. (2007). "Cabinet yet to get proposal for Silent Valley buffer zone". The Hindu. Archived from the original on 1 October 2007. Retrieved 5 October 2007.
  17. ^ "Government will consider plea for Silent Valley buffer zone: Minister". The Hindu. 2003. Archived from the original on 19 September 2006. Retrieved 18 October 2007.
  18. ^ Surendranath, C. (2007). "Silent Valley: threatened again". India Together. Retrieved 18 October 2007.
  19. ^ Govt of India. "ESZ Notification" (PDF). Govt. of India. Retrieved 14 February 2022.
  20. ^ Unnikrishnan, P. N. (1989). Silent Valley National Park Management Plan 1990.91-99.2000. Silent Valley National Park Division, Mannarghat. pp. 1–83.
  21. ^ a b c United Nations Environment Programme's World Conservation Monitoring Centre (1991). "Silent Valley National Park". UNEP-WCMC report. Archived from the original on 11 March 2007. Retrieved 3 July 2007.
  22. ^ ANCF (2006). "Nilambur-Silent Valley-Coimbatore, Perspective for the Reserve". Asian Nature Conservation Foundation. Archived from the original on 2 February 2007. Retrieved 26 March 2007.
  23. ^ Prabhakaran, G. (2009). "Monsoons shower a bounty on Silent Valley". The Hindu. pp. Front Page. Archived from the original on 12 November 2009. Retrieved 3 December 2009.
  24. ^ Suchitra, M. (2005). "Remote adivasis face health care chasm". India Together. Retrieved 3 July 2007.
  25. ^ "National Parks and Wildlife Sanctuaries, Silent Valley National Park". Retrieved 30 March 2007.
  26. ^ Balford, Edward (1873). "Kurumbar people". Cyclopædia of India and of Eastern and Southern Asia. 3. Scottish and Adelphi Presses: 341. Retrieved 30 March 2007.
  27. ^ BirdLife International 2005 World Bird Database, Version 2.0. Cambridge, UK: BirdLife International. Available: World Bird Database, accessed 3/24/2007
  28. ^ Prabhakaran, G. (13 December 2006). "New species of bird sighted in Silent Valley". The Hindu. Archived from the original on 7 November 2012. Retrieved 3 March 2007.
  29. ^ a b Gopalakrishnan, C.V. (29 July 2001). "Silent Valley, 'world's natural heritage site'". The Hindu. Archived from the original on 27 June 2003. Retrieved 22 October 2007.
  30. ^ Ramchandaran, K.K.; Joseph, Gigi, K. (2001). "Distribution and demography of diurnal primates in Silent Valley National Park and adjacent areas, Kerala, India". Journal of the Bombay Natural History Society. 98 (2). Bombay Natural History Society: 191–196. Archived from the original on 27 September 2007. Retrieved 3 March 2007.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  31. ^ George Mathew; P. Rugmini; Binoy, C. F. (2003). "Impact of forest fire on insect species diversity - a study in the Silent Valley National Park, Kerala, India" (PDF). Entomon (abstract). 28 (2). Division of Entomology, Kerala Forest Research Institute, Peechi 680 653, Kerala, India.: 105–114. Archived from the original (PDF) on 11 January 2015. Retrieved 22 April 2014.
  32. ^ Z.S.I. (1986). "Silent Valley". Records of the Zoological Survey of India. 84 (Silent Valley Special Issue). Zoological Survey of India: 1–4. Archived from the original on 27 September 2007. Retrieved 29 September 2007. cited by Mathew George and Binoy C.F., Chapter 3, AN OVERVIEW OF INSECT DIVERSITY OF WESTERN GHATS WITH SPECIAL REFERENCE TO KERALA STATE
  33. ^ Mathew, G.; Rahamathulla, V.K. (1993). "Studies on the butterflies of Silent Valley National Park". Entomon. 18 (3–4): 185–192. Retrieved 18 October 2007.[dead link]
  34. ^ Senthilmurugan, B. (2005–2008). "Mukurthi National Park: A migratory route for butterflies". Journal of the Bombay Natural History Society. 102 (2): 241–242.
  35. ^ "A safe haven for rare dragonflies". The Hindu. 7 October 2018. Retrieved 7 October 2018.
  36. ^ Zachariah, A.; V. P. Cyriac; B. Chandramohan; B. R. Ansil; J. K. Mathew; D. V. Raju; R. K. Abraham (2016). "Two new species of Raorchestes (Anura: Rhacophoridae) from the Silent Valley National Park in the Nilgiri Hills of the Western Ghats, India". Salamandra. 52 (2): 63–76.
  37. ^ "Flora and Fauna of Silent Valley National Park". Archived from the original on 29 September 2007. Retrieved 13 August 2007.
  38. ^ Manilal, K.S. (1988). Flora of Silent Valley tropical rainforests of India. Calicut: The Mathrubhumi (MM) Press. p. 398.
  39. ^ Kumar, M.; S. (1996). "Impatiens sivarajanii - a new species of Balsaminaceae from Silent Valley National Park, Kerala, India". Rheedea. 6: 51. Retrieved 3 August 2007.
  40. ^ ATREE. "Cullenia exarillata-, Projects-2". Archived from the original on 26 September 2007. Retrieved 18 October 2007.
  41. ^ Joseph, Gigi K.; Ramachandarn, K.K. (2003). "Distribution and Demography of the Nilgiri Langur (Trachypithecus johnii) in Silent Valley National Park and Adjacent Areas, Kerala, India" (PDF). Primate Conservation. 19. IUCN/SSC Primate Specialist Group: 78–82. Archived from the original (PDF) on 28 September 2007. Retrieved 18 October 2007.
  42. ^ Manilal, K.S.; Kandya, A.; Sabu, T. (1989). "A study of natural regeneration of 12 important tree species of Silent Valley tropical rain forests, Kerala, India". Journal of Tropical Forestry. 5 (1): 43–50. Retrieved 18 October 2007.[dead link]
  43. ^ Gopalakrishnan, C.V. (16 August 2001). "Bio-diversity facing extinction threat". The Hindu. Archived from the original on 7 January 2007. Retrieved 8 February 2007.{{cite news}}: CS1 maint: unfit URL (link)
  44. ^ "State of the Environment, 5.4. Biodiversity Conservation". Ministry of Environment and Forests (India). 1999. Retrieved 18 October 2007.
  45. ^ "Bureau of Plant Genetic Resources". National Bureau of Plant Genetic Resources of ICAR (India), Plant Exploration and Collection Division. Archived from the original on 19 October 2007. Retrieved 18 October 2007.
  46. ^ "A speech by HRH The Prince of Wales titled The Rainforest Lecture for Friends of the Earth, the Royal Botanic Gardens, Kew". 1990. Archived from the original on 7 October 2007. Retrieved 11 February 2007.
  47. ^ DARE/ICAR Annual Report 2002-2003 (PDF). ICAR. 2002–2003. Retrieved 18 October 2007.
  48. ^ "Threats to the forests of Kerala, Forest Fires". Kerala Forests & Wildlife Department. 2004. Archived from the original on 28 September 2007. Retrieved 18 October 2007.
  49. ^ Outlook. Hathway Investments Pvt Limited. 2005. p. 138.
  50. ^ Management in Government. Department of Administrative Reforms, Ministry of Home Affairs. 2007. p. 92.
  51. ^ a b Stone Age | Outlook India Magazine
  52. ^ Robert Clarke; Mark Merlin (1 September 2013). Cannabis: Evolution and Ethnobotany. University of California Press. pp. 226–227. ISBN 978-0-520-95457-1.
  53. ^ Panic grips tribal villages in Silent Valley – The Hindu

Further reading[edit]

  • Kerala Forest Dept. in association with Kerala Forest Research Institute, Dehra Dun (1999). Manoharan, T. M. (ed.). Silent Valley: Whispers of Reason. Thiruvananthapuram: Natraj Publishers. ISBN 8190097814.
  • Aiyappan A. (1988), Tribal Culture and Tribal Welfare By, Uma Charan Mohanty, University of Madras Dept. of Anthropology.

External links[edit]