Silent Valley National Park
Encyclopedia
Silent Valley National Park (Malayalam: സൈലന്‍റ് വാലീ നാഷണല്‍ പാര്‍ക്ക്), (Core zone: 236.74 square kilometres (91 sq mi)) is located in the Nilgiri Hills, Palakkad District
Palakkad district
Palakkad District is one of the 14 districts of the Indian state of Kerala. The city of Palakkad is the district headquarters. Palakkad is bordered on the northwest by the Malappuram District, on the southwest by the Thrissur District and on the east by Coimbatore district of Tamil Nadu. The...

 in Kerala
Kerala
or Keralam is an Indian state located on the Malabar coast of south-west India. It was created on 1 November 1956 by the States Reorganisation Act by combining various Malayalam speaking regions....

, South India
South India
South India is the area encompassing India's states of Andhra Pradesh, Karnataka, Kerala and Tamil Nadu as well as the union territories of Lakshadweep and Pondicherry, occupying 19.31% of India's area...

. The area in this national park
National park
A national park is a reserve of natural, semi-natural, or developed land that a sovereign state declares or owns. Although individual nations designate their own national parks differently A national park is a reserve of natural, semi-natural, or developed land that a sovereign state declares or...

 was historically explored in 1847 by the botanist Robert Wight
Robert Wight
Robert Wight was a Scottish surgeon and botanist who spent 30 years in India. He studied botany in Edinburgh under John Hope. He was the director of the Botanic Garden in Madras. He made use of local artists to make illustrations of the plants around him...

, and is associated with Hindu
Hindu
Hindu refers to an identity associated with the philosophical, religious and cultural systems that are indigenous to the Indian subcontinent. As used in the Constitution of India, the word "Hindu" is also attributed to all persons professing any Indian religion...

 legend.

The park is one of the last undisturbed tracts of South Western Ghats montane rain forests
South Western Ghats montane rain forests
The South Western Ghats montane rain forests are an ecoregion of southern India, covering the southern portion of the Western Ghats range in Karnataka, Kerala and Tamil Nadu, at elevations over 1000 meters...

 and tropical moist evergreen forest in India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...

. Contiguous with the proposed Karimpuzha National Park
Karimpuzha National Park
Karimpuzha National Park is a 230 km² proposed National Park located at in the Nilgiri Hills, Palakkad district, Kerala, in South India, IUCN category: PRO-History:Madras Forest Act came into force in 1882...

 (225 km²) to the north and Mukurthi National Park
Mukurthi National Park
Mukurthi National Park is a 78.46 km² protected area located in the south-eastern corner of the Nilgiris Plateau west of Ootacamund hill station in the northwest corner of Tamil Nadu state in the Western Ghats mountain range of South India...

 (78.46 km²) to the north-east, it is the core of the Nilgiri International Biosphere Reserve
Nilgiri Biosphere Reserve
The Nilgiri Biosphere Reserve is an International Biosphere Reserve in the Western Ghats, Nilgiri Hills range of South India. The Western Ghats, Nilgiri Sub-Cluster , conjoining the Nilgiri Biosphere Reserve, is under consideration by the UNESCO World Heritage Committee for selection as a World...

 (1,455.4 km²), and is part of The Western Ghats
Western Ghats
The Western Ghats, Western Ghauts or the Sahyādri is a mountain range along the western side of India. It runs north to south along the western edge of the Deccan Plateau, and separates the plateau from a narrow coastal plain along the Arabian Sea. The Western Ghats block rainfall to the Deccan...

 World Heritage Site
World Heritage Site
A UNESCO World Heritage Site is a place that is listed by the UNESCO as of special cultural or physical significance...

, Nilgiri Sub-Cluster (6,000+ km²) under consideration by UNESCO
UNESCO
The United Nations Educational, Scientific and Cultural Organization is a specialized agency of the United Nations...

.

Plans for a hydroelectric project that threatened the parks high diversity
Biodiversity
Biodiversity is the degree of variation of life forms within a given ecosystem, biome, or an entire planet. Biodiversity is a measure of the health of ecosystems. Biodiversity is in part a function of climate. In terrestrial habitats, tropical regions are typically rich whereas polar regions...

 of wildlife
Wildlife of India
The wildlife of India is a mix of species of number of different types of organism. The region's rich and diverse wildlife is preserved in 89 national parks, 13 Bio reserves and 400+ wildlife sanctuaries across the country. Since India is home to a number of rare and threatened animal species,...

 stimulated an environmentalist
Environmentalism
Environmentalism is a broad philosophy, ideology and social movement regarding concerns for environmental conservation and improvement of the health of the environment, particularly as the measure for this health seeks to incorporate the concerns of non-human elements...

 Social Movement
Indian Social Movements
List of Social movements India after 1947. This listing is separate from listing of Indian NGOs.*Appiko movement*Narmada Bachao Andolan*Chipko movement*Jhola Aandolan *Save Kudremukh*Lok Satta Movement*Save Silent Valley...

 in the 1970s called Save Silent Valley
Save Silent Valley
Save Silent Valley was a social movement aimed at the protection of Silent valley, an evergreen tropical forest in the Palakkad district of Kerala, India. It was started in 1973 to save the Silent Valley Reserve Forest in from being flooded by a hydroelectric project. The valley was declared as...

 which resulted in cancellation of the project and creation of the park in 1980. The visitors' centre for the park is at Sairandhri
Sairandhri
Sairandhri is a place in Kerala, South India at about . It is the entrance point and visitors center for Silent Valley National Park. Sairandhri is the site of a controversial hydroelectric dam that was proposed in 1958 and finally rejected in 1984....

.

History

The area is locally known as "Sairandhrivanam" literally, in Malayalam: Sairandhri's Forest. In local Hindu
Hindu
Hindu refers to an identity associated with the philosophical, religious and cultural systems that are indigenous to the Indian subcontinent. As used in the Constitution of India, the word "Hindu" is also attributed to all persons professing any Indian religion...

 legend, Sairandhri is Draupadi
Draupadi
In the epic Mahābhārata, Draupadi, also known as ' is the "emerged" daughter of King Drupada of Panchāla and the wife of the five Pandavas. When Yudhisthira becomes the king of Hastinapura at the end of the war, Draupadi becomes the queen of Indraprastha...

, the polyandrous wife of the five Pandava
Pandava
In the Hindu epic Mahābhārata, the Pandava are the five acknowledged sons of Pandu , by his two wives Kunti and Madri. Their names are Yudhisthira, Bhima, Arjuna, Nakula and Sahadeva. Although, Karna is told by Lord Krishna that according to the laws and ethics he is the first son of Kunti making...

s, who disguised herself as Sairandhri, queen Sudeshna's assistant, while they were in exile. The Pandavas, deprived of their kingdom, set out on a 14-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.

English exploration

The first English investigation of the watershed
Drainage basin
A drainage basin is an extent or an area of land where surface water from rain and melting snow or ice converges to a single point, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean...

s of the Silent Valley area was in 1847 by the botanist Robert Wight
Robert Wight
Robert Wight was a Scottish surgeon and botanist who spent 30 years in India. He studied botany in Edinburgh under John Hope. He was the director of the Botanic Garden in Madras. He made use of local artists to make illustrations of the plants around him...

. 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 there of many Lion-Tailed Macaques Macaca silenus.
In 1914 the forest of the Silent Valley area was declared a Reserve Forest
Reserve forest
You may be looking for forest reserve, a generic term associated with protected forest areas, which is also used as a specific term for protected forests in some countries...

, however, from 1927 to 1976 portions of the Silent Valley forest area were subjected to forestry
Forestry
Forestry is the interdisciplinary profession embracing the science, art, and craft of creating, managing, using, and conserving forests and associated resources in a sustainable manner to meet desired goals, needs, and values for human benefit. Forestry is practiced in plantations and natural stands...

 operations. In 1928 the location on the Kunthipuzha
Kunthipuzha
Kunthipuzha River is one of the tributaries of the river Thuthapuzha and flows through the Silent Valley. Thuthapuzha is one of the main tributaries of the Bharathapuzha River, the second-longest river in Kerala, South India....

 River at Sairandhri was identified as an ideal site for electricity generation
Electricity generation
Electricity generation is the process of generating electric energy from other forms of energy.The fundamental principles of electricity generation were discovered during the 1820s and early 1830s by the British scientist Michael Faraday...

 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.

Environmental concerns

Main article: Save Silent Valley
Save Silent Valley
Save Silent Valley was a social movement aimed at the protection of Silent valley, an evergreen tropical forest in the Palakkad district of Kerala, India. It was started in 1973 to save the Silent Valley Reserve Forest in from being flooded by a hydroelectric project. The valley was declared as...

.

Silent Valley is home to the largest population of Lion-tailed Macaque
Lion-tailed Macaque
The lion-tailed macaque is an Old World monkey that is endemic to the Western Ghats of South India.-Physical Characteristics:...

, an endangered species
Endangered species
An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...

 of Primate
Primate
A primate is a mammal of the order Primates , which contains prosimians and simians. Primates arose from ancestors that lived in the trees of tropical forests; many primate characteristics represent adaptations to life in this challenging three-dimensional environment...

. Public controversy over their habitat led to establishment of Silent Valley National Park.

In 1973 the valley became the focal point of "Save Silent Valley", India's fiercest environmental
Environmentalism
Environmentalism is a broad philosophy, ideology and social movement regarding concerns for environmental conservation and improvement of the health of the environment, particularly as the measure for this health seeks to incorporate the concerns of non-human elements...

 debate of the decade, when the Kerala State Electricity Board decided to implement the Silent Valley Hydro-Electric Project (SVHEP) centered on a dam
Dam
A dam is a barrier that impounds water or underground streams. Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees are used to manage or prevent water flow into specific land regions. Hydropower and pumped-storage hydroelectricity are...

 across the Kunthipuzha River
Kunthipuzha
Kunthipuzha River is one of the tributaries of the river Thuthapuzha and flows through the Silent Valley. Thuthapuzha is one of the main tributaries of the Bharathapuzha River, the second-longest river in Kerala, South India....

. The resulting reservoir would flood 8.3 km² of virgin rainforest
Rainforest
Rainforests are forests characterized by high rainfall, with definitions based on a minimum normal annual rainfall of 1750-2000 mm...

 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
Romulus Whitaker
Romulus Earl Whitaker is a herpetologist, wildlife conservationist and founder of the Madras Snake Park, The Andaman and Nicobar Environment Trust , and the Madras Crocodile Bank Trust....

, founder of the Madras Snake Park and the Madras Crocodile Bank
Madras Crocodile Bank Trust
The Madras Crocodile Bank Trust and Centre for Herpetology is a reptile zoo and herpetology research station, located south of the city of Chennai, in state of Tamil Nadu, India. The centre is both a registered trust and a recognized zoo under the Wildlife Act, 1972 and is India's leading...

, was probably the first person to draw public attention to the small and remote area.

In 1983 the Honorable Prime Minister of India
Prime Minister of India
The Prime Minister of India , as addressed to in the Constitution of India — Prime Minister for the Union, is the chief of government, head of the Council of Ministers and the leader of the majority party in parliament...

, Indira Gandhi
Indira Gandhi
Indira Priyadarshini Gandhara was an Indian politician who served as the third Prime Minister of India for three consecutive terms and a fourth term . She was assassinated by Sikh extremists...

, decided to abandon the Project and on November 15 the Silent Valley forests were declared as a National Park. On September 7, 1985 the Silent Valley National Park was formally inaugurated and a memorial at Sairandhri to Indira Gandhi was unveiled by Sri. Rajiv Gandhi
Rajiv Gandhi
Rajiv Ratna Gandhi was the sixth Prime Minister of India . He took office after his mother's assassination on 31 October 1984; he himself was assassinated on 21 May 1991. He became the youngest Prime Minister of India when he took office at the age of 40.Rajiv Gandhi was the elder son of Indira...

, the new Hon. Prime Minister of India. On September 1, 1986 Silent Valley National Park was designated as the core area of the Nilgiri Biosphere Reserve
Nilgiri Biosphere Reserve
The Nilgiri Biosphere Reserve is an International Biosphere Reserve in the Western Ghats, Nilgiri Hills range of South India. The Western Ghats, Nilgiri Sub-Cluster , conjoining the Nilgiri Biosphere Reserve, is under consideration by the UNESCO World Heritage Committee for selection as a World...

. Since then, a long-term conservation effort has been undertaken to preserve the Silent Valley ecosystem
Ecosystem
An ecosystem is a biological environment consisting of all the organisms living in a particular area, as well as all the nonliving , physical components of the environment with which the organisms interact, such as air, soil, water and sunlight....

.

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. 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).
During January to May 2003 a rapid Environmental Impact Assessment (EIA) was carried out. Little more was heard till November 15, 2006 when Kerala Minister for Forest Binoy Viswam said that the proposed buffer zone
Buffer zone
A buffer zone is generally a zonal area that lies between two or more other areas , but depending on the type of buffer zone, the reason for it may be to segregate regions or to conjoin them....

 for Silent Valley would be declared soon.

On February 21, 2007 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".

On April 18, 2007, Kerala Chief Minister V S Achuthanandan and his cabinet approved the Pathrakkadavu Hydro-electric project and sent it to the Union Government
Government of India
The Government of India, officially known as the Union Government, and also known as the Central Government, was established by the Constitution of India, and is the governing authority of the union of 28 states and seven union territories, collectively called the Republic of India...

 for environmental approval.

Buffer zone

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. In addition Illegal activities such as ganja cultivation, setting forest fires, trapping and poaching wild animals, frequently occur in the territorial forests located in the immediate vicinity of the national park. This has resulted in degradation of habitat and reduced forest cover, which has adverse effects on the long term survival of the core area of the national park.

On November 21, 2009, Union Minister of Forest and Environment Jairam Ramesh
Jairam Ramesh
Jairam Ramesh born April 9, 1954, is an Indian economist and an influential politician of the Congress Party in the United Progressive Alliance ruling coalition of center-left political parties heading the Government of India. He is a Member of Parliament representing Andhra Pradesh state in the...

 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. This means that the total park area is now increased to 236.74 square kilometres (91 sq mi).

On June 6, 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
Left Democratic Front
Left Democratic Front is a coalition of left winged political parties in the state of Kerala, in India. This is one of the two major political coalitions in Kerala, each of which have been in power alternatively for the last two decades. LDF is the coalition that is presently in oppposition...

 Government to protection of environment. The zone is a necessity, not just of the State but also of the nation."

The proposal was then sent to Kerala Minister for Electricity, Mr. 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 May 9, 2007 Mr. Balan has not given his opinion on the buffer zone proposal.
In August 2006, the new Minister for Forests, Benoy Viswom, 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.

In 1979, Dr. 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
Amarambalam
New Amarambalam Reserved Forest is near Nilambur town and conjoins Silent Valley National Park. Central location is . Area is 265.72 km². Altitude rises sharply from 40 m to 2,554 m....

 (80 km²), Attappadi
Attappadi
Attappadi Reserve Forest is a protected area comprising 249 km² of land covering the westernmost part of the 745 km² Attappadi block of Mannarghat Taluk in Palakkad district of Kerala, south India....

 (120 km²) in Kerala and Kunda in Coimbatore
Coimbatore
Coimbatore , also known as Kovai , is the second largest city in the Indian state of Tamil Nadu. It is a major commercial centre in Tamil Nadu and is known as the "Manchester of South India"....

 (100 km²) reserve forest
Reserve forest
You may be looking for forest reserve, a generic term associated with protected forest areas, which is also used as a specific term for protected forests in some countries...

s, should be developed into a National Rainforest Biosphere Reserve
Biosphere reserves of India
The Indian government has established 17 Biosphere Reserves of India, , which protect larger areas of natural habitat , and often include one or more National Parks and/or preserves, along buffer zones that are open to some economic uses...

.

Geography

Silent Valley is rectangular, 7 km (east-west) X 12 km (north-south). 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 plateau
Plateau
In geology and earth science, a plateau , also called a high plain or tableland, is an area of highland, usually consisting of relatively flat terrain. A highly eroded plateau is called a dissected plateau...

s of the (Nilgiris Mountains
Nilgiris (mountains)
The Nilgiri , often referred to as the Nilgiri Hills, are a range of mountains with at least 24 peaks above , in the westernmost part of Tamil Nadu state at the junction of Karnataka and Kerala states in Southern India...

) by high continuous ridges including Sispara Peak
Sispara
[Image:Peacocke-Travellers Bungalow, Sispara.jpg|thumb|350px|View to the west, of Sispara bungalow and Sispara peak across the stream in Sispara pass from the Sispara ghat trail...

 (2,206 m) at the north end of the park. The park gradually slopes southward down to the Palakkad
Palakkad
Palakkad , formerly known as Palghat, is a municipality and a town in the state of Kerala in southern India, spread over an area of 26.60 km2.The city is situated about north of state capital Thiruvananthapuram. It is the administrative headquarters of Palakkad District...

 plains and to the west it is bounded by irregular ridges. The altitude of the park ranges from 658 m to 2328 m at Anginda Peak
Anginda peak
Anginda peak is in the Nilgiri Hills of the Western Ghats in Kerala, South India. Its coordinate location is . It has an altitude is and is the highest peak in Silent Valley National Park.It is just south of Sispara pass, and forms the southernmost boundary of Mukurthi National Park in Tamil Nadu...

, 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
Granite
Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granite usually has a medium- to coarse-grained texture. Occasionally some individual crystals are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic...

 with schist
Schist
The schists constitute a group of medium-grade metamorphic rocks, chiefly notable for the preponderance of lamellar minerals such as micas, chlorite, talc, hornblende, graphite, and others. Quartz often occurs in drawn-out grains to such an extent that a particular form called quartz schist is...

s and gneiss
Gneiss
Gneiss is a common and widely distributed type of rock formed by high-grade regional metamorphic processes from pre-existing formations that were originally either igneous or sedimentary rocks.-Etymology:...

, which give rise to the loamy laterite
Laterite
Laterites are soil types rich in iron and aluminium, formed in hot and wet tropical areas. Nearly all laterites are rusty-red because of iron oxides. They develop by intensive and long-lasting weathering of the underlying parent rock...

 soils on slopes.

Rivers

The Kuntipuzha River drains
Drainage basin
A drainage basin is an extent or an area of land where surface water from rain and melting snow or ice converges to a single point, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean...

 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 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. Kuntipuzha is one of the less torrential rivers of the Western Ghats, with a pesticide-free catchment area.

Climate

Silent Valley gets copious amounts of rainfall
Precipitation (meteorology)
In meteorology, precipitation In meteorology, precipitation In meteorology, precipitation (also known as one of the classes of hydrometeors, which are atmospheric water phenomena is any product of the condensation of atmospheric water vapor that falls under gravity. The main forms of precipitation...

 during the monsoon
Monsoon
Monsoon is traditionally defined as a seasonal reversing wind accompanied by corresponding changes in precipitation, but is now used to describe seasonal changes in atmospheric circulation and precipitation associated with the asymmetric heating of land and sea...

s, but the actual amount varies within the region due the varied topography. In general the rainfall is higher at higher altitude and decreases from the west to east due to the rain shadow
Rain shadow
A rain shadow is a dry area on the lee side of a mountainous area. The mountains block the passage of rain-producing weather systems, casting a "shadow" of dryness behind them. As shown by the diagram to the right, the warm moist air is "pulled" by the prevailing winds over a mountain...

 effect. Eighty per cent of the rainfall occurs during the south-west monsoon between June and September. It also receives significant amount of rainfall during the north-east monsoon between October and November.

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 two monsoons. In the remaining months, condensation
Condensation
Condensation is the change of the physical state of matter from gaseous phase into liquid phase, and is the reverse of vaporization. When the transition happens from the gaseous phase into the solid phase directly, the change is called deposition....

 on vegetation of mist
Mist
Mist is a phenomenon of small droplets suspended in air. It can occur as part of natural weather or volcanic activity, and is common in cold air above warmer water, in exhaled air in the cold, and in a steam room of a sauna. It can also be created artificially with aerosol canisters if the...

 shrouding the valley is estimated to yield 15 per cent of the total water generated in the rainforest.

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.

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 18o C. Because of the high rainfall, the relative humidity
Relative humidity
Relative humidity is a term used to describe the amount of water vapor in a mixture of air and water vapor. It is defined as the partial pressure of water vapor in the air-water mixture, given as a percentage of the saturated vapor pressure under those conditions...

 is consistently high (above 95%) between June and December.

Tribes

There is no record the valley has ever been settled, but the Mudugar and Irula
Irulas
Irulas are a scheduled tribe of India. Irulas are present in various parts of India, but are mainly located in the Thiruvallur district of Tamil Nadu...

 tribal people are indigenous
Indigenous peoples
Indigenous peoples are ethnic groups that are defined as indigenous according to one of the various definitions of the term, there is no universally accepted definition but most of which carry connotations of being the "original inhabitants" of a territory....

 to the area and do live in the adjacent valley of Attappady Reserved Forest. Also, the Kurumbar
Kurumbar
Kurumbar or Kurumans or Kurubaru caste are shepherds of South India. They are indigenous people of India. Even though they are called in different names like 'Kurumans', 'Kurumbar' or 'Kuruba' and these names are synonyms and one and the same. They speak Kuruman tribal Kannada language. Their God...

 people occupy the highest range outside the park bordering on the Nilgiris
Nilgiris (mountains)
The Nilgiri , often referred to as the Nilgiri Hills, are a range of mountains with at least 24 peaks above , in the westernmost part of Tamil Nadu state at the junction of Karnataka and Kerala states in Southern India...

.

Many of the Mudugar and Irula now work as day labor
Day labor
Day labor is work done where the worker is hired and paid one day at a time, with no promise that more work will be available in the future. It is a form of contingent work.-Types:Day laborers find work through three common routes....

ers and porter
Porter (carrier)
A porter, also called a bearer, is a person who shifts objects for others.-Historical meaning:Human adaptability and flexibility early led to the use of humans for shifting gear...

s. Some work for the Forest Department in the park as forest guards
Security guard
A security guard is a person who is paid to protect property, assets, or people. Security guards are usually privately and formally employed personnel...

 and visitor guides
Heritage interpretation
Heritage interpretation is the communication of information about, or the explanation of, the nature, origin, and purpose of historical, natural, or cultural resources, objects, sites and phenomena using personal or non-personal methods....

. 16 out of 21 tribal colonies in the Attappady range are notorious for ganja cultivation. Many Mudugar are in abject poverty and easily recruited by the so called ganja mafia, There is a plan to employ
Contingent work
Contingent work, also sometimes known as casual work, is a neologism which describes a type of employment relationship between an employer and employee...

 50 additional men from these 21 tribal settlements as forest guards for Rs.500/man/month.

Fauna and flora

Valley areas of the park are in a Tropical and subtropical moist broadleaf forests
Tropical and subtropical moist broadleaf forests
Tropical and subtropical moist broadleaf forests , also known as tropical moist forests, are a tropical and subtropical forest biome....

 Ecoregion
Ecoregion
An ecoregion , sometimes called a bioregion, is an ecologically and geographically defined area that is smaller than an ecozone and larger than an ecosystem. Ecoregions cover relatively large areas of land or water, and contain characteristic, geographically distinct assemblages of natural...

. Hilly areas above 1,000 m are in a South Western Ghats montane rain forests
South Western Ghats montane rain forests
The South Western Ghats montane rain forests are an ecoregion of southern India, covering the southern portion of the Western Ghats range in Karnataka, Kerala and Tamil Nadu, at elevations over 1000 meters...

 region. Above 1,500 m, the evergreen forests begin to give way to stunted forests, called shola
Shola
Sholas are patches of stunted evergreen tropical and subtropical moist broadleaf forest found in valleys amid rolling grassland in the higher montane regions of South India. These patches of shola forest are found mainly in the valleys and are usually separated from one another by undulating...

s, interspersed with open grassland
Grassland
Grasslands are areas where the vegetation is dominated by grasses and other herbaceous plants . However, sedge and rush families can also be found. Grasslands occur naturally on all continents except Antarctica...

. Both are very important to naturalists
Natural science
The natural sciences are branches of science that seek to elucidate the rules that govern the natural world by using empirical and scientific methods...

, biologists and other researchers because the rich biodiversity
Biodiversity
Biodiversity is the degree of variation of life forms within a given ecosystem, biome, or an entire planet. Biodiversity is a measure of the health of ecosystems. Biodiversity is in part a function of climate. In terrestrial habitats, tropical regions are typically rich whereas polar regions...

 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
BirdLife International
BirdLife International is a global Partnership of conservation organisations that strives to conserve birds, their habitats and global biodiversity, working with people towards sustainability in the use of natural resources...

  16 bird species in Silent Valley as threatened or restricted: Nilgiri Wood-pigeon
Nilgiri Wood-pigeon
The Nilgiri Wood Pigeon is large pigeon found in the moist deciduous forests and sholas of the Western Ghats in southwestern India. They are mainly frugivorous and forage in the canopy of dense hill forests...

, Malabar Parakeet
Malabar Parakeet
The Malabar Parakeet also known as the Blue-winged Parakeet, is a species of parakeet endemic to the Western Ghats of southern India. Found in small flocks, they fly rapidly in forest clearings while making screeching calls that differ from those of other parakeet species within their distribution...

,, ], Grey-headed Bulbul
Grey-headed Bulbul
The Grey-headed Bulbul is a member of the bulbul family of passerine birds. It is endemic to the Western Ghats of south-west India, found from Goa south to Tamil Nadu, at altitudes up to 1200m. It is found in dense reeds or thickets mainly near rivers and swampy areas inside forests...

, Broad-tailed Grassbird
Old World warbler
The "Old World Warblers" is the name used to describe a large group of birds formerly grouped together in the bird family Sylviidae. The family held over 400 species in over 70 genera, and were the source of much taxonomic confusion. Two families were split out initially, the cisticolas into...

, Rufous Babbler
Rufous Babbler
The Rufous Babbler is an Old World babbler endemic to the Western Ghats of southern India. It is dark brown and long tailed, and is usually seen foraging in noisy groups along open hillsides grass or forest.-Description:...

, Wynaad Laughing Thrush, Nilgiri Laughing Thrush
Rufous-breasted Laughingthrush
The Rufous-breasted, Black-chinned or Nilgiri Laughingthrush, Trochalopteron cachinnans, is a species of Laughingthrush endemic to Peninsular India.-Taxonomy:...

, White-bellied Shortwing, [

Rare bird species found here include Ceylon Frogmouth and Great Indian Hornbill. The 2006 winter bird survey discovered Long-legged Buzzard
Long-legged Buzzard
The Long-legged Buzzard is a bird of prey.-Description:It is similar in appearance to the Rough-legged Buzzard , but larger and more robust. There are many different colour forms, but usually Long-leggeds have a clear orange tint to the plumage, red or orange tail, pale head and largely white...

, a new species of raptor at Sispara
Sispara
[Image:Peacocke-Travellers Bungalow, Sispara.jpg|thumb|350px|View to the west, of Sispara bungalow and Sispara peak across the stream in Sispara pass from the Sispara ghat trail...

, the park's highest peak. The survey found 10 endangered species recorded in the IUCN Red List
IUCN Red List
The IUCN Red List of Threatened Species , founded in 1963, is the world's most comprehensive inventory of the global conservation status of biological species. The International Union for Conservation of Nature is the world's main authority on the conservation status of species...

 including the Red winged crested cuckoo
Chestnut-winged Cuckoo
The Chestnut-winged Cuckoo or Red-winged Crested Cuckoo is a cuckoo found in Southeast Asia and parts of South Asia. It has dark glossy upperparts, a black head with long crest chestnut wings, a long graduated glossy black tail, rufous throat dusky underside and a narrow white nuchal half collar...

, Malabar Pied Hornbill
Malabar Pied Hornbill
The Malabar Pied Hornbill is a hornbill. Hornbills are a family of tropical near-passerine birds found in the Old World....

, Pale harrier
Pallid Harrier
The Pale or Pallid Harrier is a migratory bird of prey of the harrier family. It breeds in southern parts of eastern Europe and central Asia and winters mainly in India and southeast Asia...

. The area is home to 15 endemic species including the Black-and-orange Flycatcher
Black-and-orange Flycatcher
The Black-and-orange Flycatcher is a species of flycatcher endemic to the central and southern Western Ghats, the Nilgiris and Palni hill ranges in southern India...

. It recorded 138 species of birds including 17 species that were newly observed in the Silent Valley area. The most abundant bird was the Black bulbul
Black Bulbul
The Black Bulbul , also known as the Himalayan Black Bulbul, Asian Black Bulbul or Square-tailed Bulbul, is a member of the bulbul family of passerine birds. It is found in southern Asia from India east to southern China. It is the type species of the genus Hypsipetes, established by Nicholas...

.

Mammals

There are at least 34 species of mammal
Mammal
Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...

s at Silent Valley including the threatened Lion-tailed Macaque
Lion-tailed Macaque
The lion-tailed macaque is an Old World monkey that is endemic to the Western Ghats of South India.-Physical Characteristics:...

, Niligiri Langur
Black-footed Gray Langur
The black-footed gray langur is an Old World monkey, one of the species of langurs. This, like other gray langurs, is a leaf-eating monkey found in south India.-References:...

, Malabar Giant Squirrel
Indian Giant Squirrel
The Indian giant squirrel, or Malabar giant squirrel, is a large tree squirrel species genus Ratufa native to India. It is a large-bodied diurnal, arboreal, and herbivorous squirrel found in South Asia.-Description:...

, Nilgiri Tahr
Nilgiri Tahr
The Nilgiri Tahr, Nilgiritragus hylocrius, known locally as the Nilgiri Ibex or simply Ibex, is an ungulate that is endemic to the Nilgiri Hills and the southern portion of the Western Ghats in the states of Tamil Nadu and Kerala in southern India. It is the state animal of Tamil Nadu...

, Peshwa’s Bat
Bat
Bats are mammals of the order Chiroptera "hand" and pteron "wing") whose forelimbs form webbed wings, making them the only mammals naturally capable of true and sustained flight. By contrast, other mammals said to fly, such as flying squirrels, gliding possums, and colugos, glide rather than fly,...

 (Myotis peshwa) and Hairy-winged Bat
Hairy-winged Bat
Lesser Hairy-winged Bat is a species of vesper bat in the Vespertilionidae family.It can be found in the following countries: India, Indonesia, Philippines, and Taiwan. They are known to eat various species of beetles....

. There are nine species of bat
Bat
Bats are mammals of the order Chiroptera "hand" and pteron "wing") whose forelimbs form webbed wings, making them the only mammals naturally capable of true and sustained flight. By contrast, other mammals said to fly, such as flying squirrels, gliding possums, and colugos, glide rather than fly,...

s, rat
Rat
Rats are various medium-sized, long-tailed rodents of the superfamily Muroidea. "True rats" are members of the genus Rattus, the most important of which to humans are the black rat, Rattus rattus, and the brown rat, Rattus norvegicus...

s and mice
MICE
-Fiction:*Mice , alien species in The Hitchhiker's Guide to the Galaxy*The Mice -Acronyms:* "Meetings, Incentives, Conferencing, Exhibitions", facilities terminology for events...

.

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
Nilgiri Langur
The Nilgiri langur is a lutung found in the Nilgiri Hills of the Western Ghats in South India. Its range also includes Kodagu in Karnataka,Kodayar Hills in Tamil Nadu and many other hilly areas in Kerala and Tamil nadu. This primate has glossy black fur on its body and golden brown fur on its head...

, fifteen troops of bonnet macaque
Bonnet Macaque
The bonnet macaque is a macaque endemic to southern India. Its distribution is limited by the Indian Ocean on three sides and the Godavari and Tapti Rivers along with a related competing species of rhesus macaque in the north....

 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.

The tiger
Tiger
The tiger is the largest cat species, reaching a total body length of up to and weighing up to . Their most recognizable feature is a pattern of dark vertical stripes on reddish-orange fur with lighter underparts...

, leopard
Leopard
The leopard , Panthera pardus, is a member of the Felidae family and the smallest of the four "big cats" in the genus Panthera, the other three being the tiger, lion, and jaguar. The leopard was once distributed across eastern and southern Asia and Africa, from Siberia to South Africa, but its...

 (panther), leopard cat
Leopard Cat
The leopard cat is a small wild cat of South and East Asia. Since 2002 it has been listed as Least Concern by IUCN as it is widely distributed but threatened by habitat loss and hunting in parts of its range...

, jungle cat
Jungle Cat
The jungle cat is a medium-sized cat and considered the largest remaining species of the wild cat genus Felis. The species is also called the swamp lynx but is not closely related to the lynxes....

, fishing cat
Fishing Cat
The Fishing Cat is a medium-sized wild cat of South and Southeast Asia. In 2008, the IUCN classified the fishing cat as endangered since they are concentrated primarily in wetland habitats, which are increasingly being settled, degraded and converted...

, Common Palm Civet, Small Indian Civet
Small Indian Civet
The Small Indian Civet or Rasse is a species of civet found across south and South-east Asia as well as in the Indonesian archipelago. The Assamese name Johamaal refers to its glandular odour similar to a scented rice variety called Joha...

, Brown Palm Civet, Ruddy Mongoose
Ruddy Mongoose
The Ruddy Mongoose is a species of mongoose found in hill forests of peninsular India and Sri Lanka. This mongoose along with the Striped-necked Mongoose are the only mongoose species endemic to India and Sri Lanka....

, Stripe-necked Mongoose, Dhole
Dhole
The dhole is a species of canid native to South and Southeast Asia. It is the only extant member of the genus Cuon, which differs from Canis by the reduced number of molars and greater number of teats...

, clawless otter
Otter
The Otters are twelve species of semi-aquatic mammals which feed on fish and shellfish, and also other invertebrates, amphibians, birds and small mammals....

, sloth bear
Sloth Bear
The sloth bear , also known as the labiated bear, is a nocturnal insectivorous species of bear found wild within the Indian subcontinent. The sloth bear evolved from ancestral brown bears during the Pleistocene and shares features found in insect-eating mammals through convergent evolution...

, small travancore flying squirrel
Flying squirrel
Flying squirrels, scientifically known as Pteromyini or Petauristini, are a tribe of 44 species of squirrels .- Description :...

, Indian pangolin (scaly anteater), porcupine
Porcupine
Porcupines are rodents with a coat of sharp spines, or quills, that defend or camouflage them from predators. They are indigenous to the Americas, southern Asia, and Africa. Porcupines are the third largest of the rodents, behind the capybara and the beaver. Most porcupines are about long, with...

, wild boar
Boar
Wild boar, also wild pig, is a species of the pig genus Sus, part of the biological family Suidae. The species includes many subspecies. It is the wild ancestor of the domestic pig, an animal with which it freely hybridises...

, sambar
Sambar Deer
The Sambar ' is a large deer native to southern and southeast Asia. Although it primarily refers to R. unicolor, the name "Sambar" is also sometimes used to refer to the Philippine Deer and the Rusa Deer...

, spotted deer, barking deer, mouse deer and gaur
Gaur
The gaur , also called Indian bison, is a large bovine native to South Asia and Southeast Asia. The species is listed as vulnerable on the IUCN Red List since 1986 as the population decline in parts of the species' range is likely to be well over 70% over the last three generations...

 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
Lepidoptera
Lepidoptera is a large order of insects that includes moths and butterflies . It is one of the most widespread and widely recognizable insect orders in the world, encompassing moths and the three superfamilies of butterflies, skipper butterflies, and moth-butterflies...

 and Coleoptera. Many unclassified species have been collected and there is a need for further studies.

33 species of crickets and grasshoppers
Orthoptera
Orthoptera is an order of insects with paurometabolous or incomplete metamorphosis, including the grasshoppers, crickets and locusts.Many insects in this order produce sound by rubbing their wings against each other or their legs, the wings or legs containing rows of corrugated bumps...

 have been recorded of which one was new. 39 species of true bugs
Hemiptera
Hemiptera is an order of insects most often known as the true bugs , comprising around 50,000–80,000 species of cicadas, aphids, planthoppers, leafhoppers, shield bugs, and others...

 (six new) and two species of Homoptera
Homoptera
Homoptera is a deprecated suborder of order Hemiptera; recent morphological studies and DNA analysis strongly suggests that the order is paraphyletic. It was therefore split into the suborders Sternorrhyncha, Auchenorrhyncha, and Coleorrhyncha....

 (both new) have been recorded. 128 species of beetles including 10 new species have been recorded.

Over 128 species of butterflies
Butterfly
A butterfly is a mainly day-flying insect of the order Lepidoptera, which includes the butterflies and moths. Like other holometabolous insects, the butterfly's life cycle consists of four parts: egg, larva, pupa and adult. Most species are diurnal. Butterflies have large, often brightly coloured...

 and 400 species of moth
Moth
A moth is an insect closely related to the butterfly, both being of the order Lepidoptera. Moths form the majority of this order; there are thought to be 150,000 to 250,000 different species of moth , with thousands of species yet to be described...

s live here. A 1993 study found butterflies belonging to 9 families. The families Nymphalidae
Nymphalidae
The Nymphalidae is a family of about 5,000 species of butterflies which are distributed throughout most of the world. These are usually medium sized to large butterflies. Most species have a reduced pair of forelegs and many hold their colourful wings flat when resting. They are also called...

 and Papilionidae contained the maximum number of species. 13 species were endemic to South India, including 5 species having protected status.
7 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. The bird species included the Pied Bushchat Saxicola caprata, Nilgiri Pipit
Pipit
The pipits are a cosmopolitan genus, Anthus, of small passerine birds with medium to long tails. Along with the wagtails and longclaws, the pipits make up the family Motacillidae...

 Anthus nilghiriensis, Tickell's Warbler Phylloscopus affinis, Greenish Leaf-Warbler Phylloscopus trochiloides and the Oriental White-eye Zosterops
Zosterops
Zosterops is a genus of birds containing the typical white-eyes. They are traditionally placed in the white-eye family, Zosteropidae, which may actually be a part of the Timaliidae, however...

 palpebrosa
.

At least 500 species of earthworm
Earthworm
Earthworm is the common name for the largest members of Oligochaeta in the phylum Annelida. In classical systems they were placed in the order Opisthopora, on the basis of the male pores opening posterior to the female pores, even though the internal male segments are anterior to the female...

s and leech
Leech
Leeches are segmented worms that belong to the phylum Annelida and comprise the subclass Hirudinea. Like other oligochaetes such as earthworms, leeches share a clitellum and are hermaphrodites. Nevertheless, they differ from other oligochaetes in significant ways...

es 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 fern
Fern
A fern is any one of a group of about 12,000 species of plants belonging to the botanical group known as Pteridophyta. Unlike mosses, they have xylem and phloem . They have stems, leaves, and roots like other vascular plants...

s and fern allies, 200 liverwort
Marchantiophyta
The Marchantiophyta are a division of bryophyte plants commonly referred to as hepatics or liverworts. Like other bryophytes, they have a gametophyte-dominant life cycle, in which cells of the plant carry only a single set of genetic information....

s, 75 lichen
Lichen
Lichens are composite organisms consisting of a symbiotic organism composed of a fungus with a photosynthetic partner , usually either a green alga or cyanobacterium...

s and about 200 algae
Algae
Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms, such as the giant kelps that grow to 65 meters in length. They are photosynthetic like plants, and "simple" because their tissues are not organized into the many...

. A majority Of these plants are endemic to the Western Ghats.

In addition to facilitating recharge of the aquifer
Aquifer
An aquifer is a wet underground layer of water-bearing permeable rock or unconsolidated materials from which groundwater can be usefully extracted using a water well. The study of water flow in aquifers and the characterization of aquifers is called hydrogeology...

, water retention of the catchment basin and preventing soil erosion, every plant in the park from the smallest one celled algae
Algae
Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms, such as the giant kelps that grow to 65 meters in length. They are photosynthetic like plants, and "simple" because their tissues are not organized into the many...

 to the largest tree in the forest has unknown potential for beneficial innovations in biotechnology
Biotechnology
Biotechnology is a field of applied biology that involves the use of living organisms and bioprocesses in engineering, technology, medicine and other fields requiring bioproducts. Biotechnology also utilizes these products for manufacturing purpose...

.

Flowering plants

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
Orchidaceae
The Orchidaceae, commonly referred to as the orchid family, is a morphologically diverse and widespread family of monocots in the order Asparagales. Along with the Asteraceae, it is one of the two largest families of flowering plants, with between 21,950 and 26,049 currently accepted species,...

with 108 species including the rare, endemic and highly endangered orchids Ipsea
Ipsea
Ipsea is a genus of the Orchid family , endemic to India, Sri Lanka and North America.-List of species:*Ipsea malabarica*Ipsea speciosa*Ipsea thailandica*Ipsea thomsoniana*Ipsea wrayana...

 malabarica, Bulbophyllum
Bulbophyllum
Bulbophyllum is the largest genus in the orchid family Orchidaceae. With more than 2,000 species, it is also one of the largest genera of flowering plants, exceeded only by Astragalus...

 silentvalliensis and Eria tiagii, Grasses
Poaceae
The Poaceae is a large and nearly ubiquitous family of flowering plants. Members of this family are commonly called grasses, although the term "grass" is also applied to plants that are not in the Poaceae lineage, including the rushes and sedges...

(56), Legumes
Fabaceae
The Fabaceae or Leguminosae, commonly known as the legume, pea, or bean family, is a large and economically important family of flowering plants. The group is the third largest land plant family, behind only the Orchidaceae and Asteraceae, with 730 genera and over 19,400 species...

(55), Rubiaceae
Rubiaceae
The Rubiaceae is a family of flowering plants, variously called the coffee family, madder family, or bedstraw family. The group contains many commonly known plants, including the economically important coffee , quinine , and gambier , and the horticulturally valuable madder , west indian jasmine ,...

(49) and Asters
Asteraceae
The Asteraceae or Compositae , is an exceedingly large and widespread family of vascular plants. The group has more than 22,750 currently accepted species, spread across 1620 genera and 12 subfamilies...

(45). There are many rare, endemic and economically valuable species, such as cardamom
Cardamom
Cardamom refers to several plants of the genera Elettaria and Amomum in the ginger family Zingiberaceae. Both genera are native to India and Bhutan; they are recognised by their small seed pod, triangular in cross-section and spindle-shaped, with a thin papery outer shell and small black seeds...

 Ellettaria cardamomum, black pepper
Black pepper
Black pepper is a flowering vine in the family Piperaceae, cultivated for its fruit, which is usually dried and used as a spice and seasoning. The fruit, known as a peppercorn when dried, is approximately in diameter, dark red when fully mature, and, like all drupes, contains a single seed...

 Piper nigrum, yams
Yam (vegetable)
Yam is the common name for some species in the genus Dioscorea . These are perennial herbaceous vines cultivated for the consumption of their starchy tubers in Africa, Asia, Latin America and Oceania...

 Dioscorea spp., beans Phaseolus sp., a pest-resistant strain of rice
Rice
Rice is the seed of the monocot plants Oryza sativa or Oryza glaberrima . As a cereal grain, it is the most important staple food for a large part of the world's human population, especially in East Asia, Southeast Asia, South Asia, the Middle East, and the West Indies...

 Oryza Pittambi, and 110 plant species of importance in Ayurvedic
Ayurveda
Ayurveda or ayurvedic medicine is a system of traditional medicine native to India and a form of alternative medicine. In Sanskrit, words , meaning "longevity", and , meaning "knowledge" or "science". The earliest literature on Indian medical practice appeared during the Vedic period in India,...

 medicine. Seven new plant species have been recorded from Silent Valley, including in 1996, Impatiens sivarajanii
Impatiens sivarajanii
Impatiens sivarajanii is a species of perennial flowering plant.-References:* Rheedea 6:51. 1996* USDA, ARS, National Genetic Resources Program. Germplasm Resources Information Network - [Online Database]....

, a new species of Balsaminaceae
Balsaminaceae
Balsaminaceae are a family of dicotyledonous plants, comprising two genera and 850+ species, all but one of which belong to the genus Impatiens...

.

Trees

Occurrence of lion-tailed macaque is dependent on the flowering of Cullenia
Cullenia
Cullenia is a genus of flowering plants native to India and Sri Lanka. Earlier classification schemes place the genus in the Kapok-tree family , but the Angiosperm Phylogeny Group places it in the Malva family ....

 exarillata
in the forest.

Six distinct tree associations have been described in the valley. Three are restricted to the southern sector: (Cullenia exarillata & Palaquium ellipticum), (Palaquium ellipticum & Mesua ferrea
Mesua ferrea
Mesua ferrea is a species in the family Calophyllaceae. The plant is named after the heaviness of its timber and cultivated in tropical climates for its form, foliage, and fragrant flowers...

(Indian rose chestnut) and (Mesua ferrea & Calophyllum
Calophyllum
Calophyllum is a flowering plant genus of around 180-200 species of tropical evergreen trees in the family Calophyllaceae. The generic name is derived from the Greek words καλος , meaning "beautiful", and φυλλον , meaning "leaf." Its members are native to Australasia, Madagascar, Eastern Africa,...

 elatum)
. The remainder are confined to the central and northern parts of the Park: (Palaquium ellipticum & Poeciloneuron
Poeciloneuron
Poeciloneuron is a plant genus in the family Calophyllaceae....

 indicum), (Calophyllum elatum & Ochlandra
Ochlandra
Ochlandra is a genus of bamboo . The genus comprises nine species, of which eight are endemic to the Western Ghats ....

 sp.)
and (Poeciloneuron
Poeciloneuron
Poeciloneuron is a plant genus in the family Calophyllaceae....

 indicum & Ochlandra
Ochlandra
Ochlandra is a genus of bamboo . The genus comprises nine species, of which eight are endemic to the Western Ghats ....

 sp.)
.

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
Elaeocarpus
Elaeocarpus is a genus of tropical and subtropical evergreen trees and shrubs. The approximately 350 species are distributed from Madagascar in the west through India, Southeast Asia, Malaysia, southern China, and Japan, through Australia to New Zealand, Fiji, and Hawaii in the east. The islands of...

 glandulosus, Litsea
Litsea
Litsea is a genus of evergreen or deciduous trees or shrubs belonging to the Laurel family, Lauraceae. The genus includes 200 to 400 species in tropical and subtropical areas of both hemispheres.-Overview:Trees or shrubs, dioecious...

 floribunda, Mesua nagassarium, Cinnamomum
Cinnamomum
Cinnamomum is a genus of evergreen aromatic trees and shrubs belonging to the Laurel family, Lauraceae. The species of Cinnamomum have aromatic oils in their leaves and bark. The genus contains over 300 species, distributed in tropical and subtropical regions of North America, Central America,...

 malabatrum, Agrostistachys
Agrostistachys
Agrostistachys is a plant genus of the family Euphorbiaceae. It comprises 9 species, present from India to West Malesia. 5 species are found in Malesia.Species include:*Agrostistachys coriacea*Agrostistachys hookeri*Agrostistachys indica...

 meeboldii, Calophyllum
Calophyllum
Calophyllum is a flowering plant genus of around 180-200 species of tropical evergreen trees in the family Calophyllaceae. The generic name is derived from the Greek words καλος , meaning "beautiful", and φυλλον , meaning "leaf." Its members are native to Australasia, Madagascar, Eastern Africa,...

 polyanthum, Garcinia
Garcinia
Garcinia is a plant genus of the family Clusiaceae native to Asia, Australia, tropical and southern Africa, and Polynesia. The number of species is highly disputed, with various sources recognizing between 50 and about 300 taxa as specifically valid...

 morella
and Actinodaphne
Actinodaphne
Actinodaphne is an Asian genus of the family Lauraceae, Laurel bay related, that comprises a group of flowering plants within the order Laurales.-Overview:...

 campanulata
.

Recent selective felling of three trees per acre, has led to the cutting of 48,000 m³ of timber from about 20 km².

There is a huge hollow Kattualying tree here which can fit 12 people inside.

Genetic resources

Throughout human history about 10% of the genetic stock found in the wild has been bred
Breed
A breed is a group of domestic animals or plants with a homogeneous appearance, behavior, and other characteristics that distinguish it from other animals or plants of the same species. Despite the centrality of the idea of "breeds" to animal husbandry, there is no scientifically accepted...

 into palatable and higher yielding cereals, fruits and vegetables. Future food security
Food security
Food security refers to the availability of food and one's access to it. A household is considered food-secure when its occupants do not live in hunger or fear of starvation. According to the World Resources Institute, global per capita food production has been increasing substantially for the past...

 depends on the preservation of the remaining 90% of the stock through protection of high biodiversity habitats like Silent valley.

The National Bureau of Plant Genetic Resources of ICAR (India), Plant Exploration and Collection Division has identified Silent Valley as high in bio-diversity and an important Gene Pool
Gene pool
In population genetics, a gene pool is the complete set of unique alleles in a species or population.- Description :A large gene pool indicates extensive genetic diversity, which is associated with robust populations that can survive bouts of intense selection...

 resource for Recombinant DNA
Recombinant DNA
Recombinant DNA molecules are DNA sequences that result from the use of laboratory methods to bring together genetic material from multiple sources, creating sequences that would not otherwise be found in biological organisms...

 innovations. An important example of use of wild germplasm
Germplasm
A germplasm is a collection of genetic resources for an organism. For plants, the germplasm may be stored as a seed collection or, for trees, in a nursery.-See also:*Germ plasm, the germ cell determining zone...

 is gene selection from the wild varieties of rice Oryza
Oryza
Oryza is a genus of seven to twenty species of grasses in the tribe Oryzeae, within the subfamily Bambusoideae, native to tropical and subtropical regions of Asia, Northern Australia and Africa...

 nivara
(Central India) and Oryza Pittambi found in Silent Valley for the traits of broad spectrum disease resistance in high yielding hybrid rice
Rice
Rice is the seed of the monocot plants Oryza sativa or Oryza glaberrima . As a cereal grain, it is the most important staple food for a large part of the world's human population, especially in East Asia, Southeast Asia, South Asia, the Middle East, and the West Indies...

 varieties including IR-36, which are responsible for much of the Green Revolution
Green Revolution
Green Revolution refers to a series of research, development, and technology transfer initiatives, occurring between the 1940s and the late 1970s, that increased agriculture production around the world, beginning most markedly in the late 1960s....

 throughout Asia.

Also, genetic evaluation of plant growth promoting Rhizobacteria
Rhizobia
Rhizobia are soil bacteria that fix nitrogen after becoming established inside root nodules of legumes . Rhizobia require a plant host; they cannot independently fix nitrogen...

 obtained from Silent Valley indicated that strain, IISR 331, could increase the growth of black pepper
Black pepper
Black pepper is a flowering vine in the family Piperaceae, cultivated for its fruit, which is usually dried and used as a spice and seasoning. The fruit, known as a peppercorn when dried, is approximately in diameter, dark red when fully mature, and, like all drupes, contains a single seed...

 cuttings by 228% and showed 82.7% inhibition of the common plant wilting disease Phytopthora capsici in laboratory tests (in vitro
In vitro
In vitro refers to studies in experimental biology that are conducted using components of an organism that have been isolated from their usual biological context in order to permit a more detailed or more convenient analysis than can be done with whole organisms. Colloquially, these experiments...

).

Forest fire

Fire is one of the major threats facing the forests of 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. Some extent of the Mesua
Mesua
Mesua is a small genus of flowering plants in the family Calophyllaceae, native to tropical southern Asia. Common names include ironwood and rose chestnut....

 - Calophyllum tree association areas in the higher reaches are degraded due to previous fire and the area is now fast regenerating.

Cannabis cultivation

The cannabis
Cannabis
Cannabis is a genus of flowering plants that includes three putative species, Cannabis sativa, Cannabis indica, and Cannabis ruderalis. These three taxa are indigenous to Central Asia, and South Asia. Cannabis has long been used for fibre , for seed and seed oils, for medicinal purposes, and as a...

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.

External sources


This volume is a tribute to nature and vouches for what can be achieved when naturalists, forestry experts and scientists join hands for the cause of conservation.
  • Aiyappan A. (1988), Tribal Culture and Tribal Welfare By, Uma Charan Mohanty, University of Madras Dept. of Anthropology.
  • From Mukkali to Sairandhri in Silent Valley National Park 37 photos
  • Silent Valley National Park A Travel Blog
  • silentvalley.gov.in
  • "Only An Axe Away" This 40 minute, 2004, documentary film narrates the history of the unique campaign to save the Silent Valley from destructive development. The threat to Silent Valley does not cease! Direction: P Baburaj & C Saratchandran
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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