Envis Centre, Ministry of Environment & Forest, Govt. of India

Printed Date: Sunday, November 28, 2021

Western Ghats

 

 

 

 

 

 

 

 

 

The Western Ghats are a chain of low mountains running 1,600 kilometres parallel to India’s western coast from Gujarat to southern Kerala between 30-50 kilometres inland. They have some of the finest non-equatorial tropical evergreen forests in the world with very high levels of speciation and endemism. They shelter at least 325 globally threatened species including 51 that are critically endangered. The serial site contains 39 protected areas in seven separate clusters stretching over a distance of 1,250 kilometres. 

 

 

 

Outstanding Universal Value 

 

 

 

The Western Ghats are internationally recognized as a region of immense global importance for the conservation of biological diversity, besides containing areas of high geological, cultural and aesthetic values. A chain of mountains running parallel to India’s western coast, approximately 30-50 km inland, the Ghats traverse the States of Kerala, Tamil Nadu, Karnataka, Goa, Maharashtra and Gujarat. These mountains cover an area of around 140,000 km² in a 1,600 km long stretch that is interrupted only by the 30 km Palghat Gap at around 11°N. 

 

 

Older than the great Himalayan mountain chain, the Western Ghats of India are a geomorphic feature of immense global importance. The Outstanding Universal Value of the Western Ghats is manifested in the region’s unique and fascinating influence on large-scale biophysical and ecological processes over the entire Indian peninsula. 

 

 

The mountains of the Western Ghats and their characteristic montane forest ecosystems influence the Indian monsoon weather patterns that mediate the warm tropical climate of the region, presenting one of the best examples of the tropical monsoon system on the planet. The Ghats act as a key barrier, intercepting the rain-laden monsoon winds that sweep in from the south-west during late summer. 

 

 

A significant characteristic of the Western Ghats is the exceptionally high level of biological diversity and endemism. This mountain chain is recognized as one of the world’s eight ‘hottest hotspots’ of biological diversity along with Sri Lanka. The forests of the Western Ghats include some of the best representatives of non equatorial tropical evergreen forests in the world. At least 325 globally threatened (IUCN Red Data List) species occur in the Western Ghats. The globally threatened flora and fauna in the Western Ghats are represented by 229 plant species, 31 mammal species, 15 bird species, 43 amphibian species, 5 reptile species and 1 fish species. Of the total 325 globally threatened species in the Western Ghats, 129 are classified as Vulnerable, 145 as Endangered and 51 as Critically Endangered. 

 

 

Criterion (ix): The Western Ghats region demonstrates speciation related to the breakup of the ancient landmass of Gondwanaland in the early Jurassic period; secondly to the formation of India into an isolated landmass and the thirdly to the Indian landmass being pushed together with Eurasia. Together with favourable weather patterns and a high gradient being present in the Ghats, high speciation has resulted. The Western Ghats is an “Evolutionary Ecotone” illustrating “Out of Africa” and “Out of Asia” hypotheses on species dispersal and vicariance. 

 

 

Criterion (x): The Western Ghats contain exceptional levels of plant and animal diversity and endemicity for a continental area. In particular, the level of endemicity for some of the 4-5,000 plant species recorded in the Ghats is very high: of the nearly 650 tree species found in the Western Ghats, 352 (54%) are endemic. Animal diversity is also exceptional, with amphibians (up to 179 species, 65% endemic), reptiles (157 species, 62% endemic), and fishes (219 species, 53% endemic). Invertebrate biodiversity, once better known, is likely also to be very high (with some 80% of tiger beetles endemic). A number of flagship mammals occur in the property, including parts of the single largest population of globally threatened ‘landscape’ species such as the Asian Elephant, Gaur and Tiger. Endangered species such as the lion-tailed Macaque, Nilgiri Tahr and Nilgiri Langur are unique to the area. The property is also key to the conservation of a number of threatened habitats, such as unique seasonally mass-flowering wildflower meadows, Shola forests and Myristica swamps. 

 

 

 

 

Western Ghats World Heritage sub clusters

 

 

 

Agasthyamalai Sub-Cluster (with Five Site Elements) 

 

 

 

The Agasthyamalai region constitutes an extensive and compact tract of forest-clad mountains, called the Ashamabu or Agasthyamalai hills, in the extreme south of the Western Ghats. Distributed from just south of the Ariankavu Pass (a minor pass at around 9° N) to the vicinity of the Mahendragiri peak near Kanyakumari, the hills span an altitudinal range from near sea level (50 m) to the highest peak, the venerated Agasthyamalai (1,868 m), after which this region is named. The region receives precipitation from both the southwest and northeast monsoons and has a very short dry season of less than 2-3 months duration. Thus, much of the area is covered in tropical moist forest vegetation, with drier forests occurring chiefly in the rain-shadow regions along the eastern foothills. 

 

 

On the eastern side, the Kalakad-Mundanthurai Tiger Reserve (KMTR), the secondlargest protected area in Tamil Nadu State, spans an altitude of 50 to 1,700 m in elevation, with tropical wet evergreen forests (rainforests) occurring chiefly above 500 m. The topography is rugged with numerous perennial hill streams originating from the tropical rainforest areas on the upper slopes and that confluence to form major rivers such as the Tambiraparani, Manimuthar and Ramanadhi, which support the agricultural economy of millions in the adjoining plains. The forests of the reserve include the catchment area of the Manimuthar, Kodayar, Servalar and Karaiar dams. 

 

 

On the west, three protected areas (Neyyar, Peppara and Shendurney Wildlife Sanctuaries) along with the Kulathupuzha and Palode Reserved Forests form an almost equally extensive and contiguous tract of forest in Kerala. The rivers Kallada, Achankoil, Vamanapuram, Karamana and Neyyar drain this region. The three wildlife sanctuaries include catchment areas upstream of three dams (Neyyar on the Neyyar river, Peppara on the Karamana river and Parappar on the Kallad river in Shendurney). 

 

 

 

Periyar Sub-Cluster (with Six Site Elements) 

 

 

 

The Periyar sub-cluster extends from north of the Ariankavu pass (at c. 9° N) over the region known as the Cardamom Hills to around Kumily in the northern boundary of the Periyar Tiger Reserve. To the south of the Periyar Tiger Reserve are the reserved forests of the Ranni, Konni and Achankovil Forest Divisions. On the eastern side, lying largely in a rain-shadow area with mostly drier forests, lies the Srivilliputtur Wildlife Sanctuary and reserved forests of the Tirunelveli Forest Division. The region spans a mostly forested tract of around 2,806 km². The region also spans an elevation range from around 100 m to over 2,000 m (2,019 m at Kottamalai) of mountainous terrain with deep valleys, and includes the drainages of the west flowing Periyar, Mullakudy and Pamba rivers. The Periyar was dammed in 1895 and the resulting reservoir, which submerged 2,600 ha of forest, was leased to the then Government of Madras for a period of 999 years. The area experiences winter temperatures of around from 15°C going up to 31°C in summer (April-May). The annual rainfall of 2,000 mm to 3,000 mm in Periyar decreases to less than 1,500 mm in the east in Srivilliputtur Wildlife Sanctuary. On the western side, two-thirds of the precipitation is received during the southwest monsoon from June to September. The areas also receive rainfall from the northeast monsoon (October-December) and from pre-monsoon showers (April-May). 

 

 

 

Anamalai Sub-Cluster (with Seven Site Elements) 

 

 

 

The Anamalai (meaning ‘elephant hills’ in Tamil) ranges are a major conservation area in the southern Western Ghats. The ranges occur just south of the Palghat gap and are linked with the Nelliampathy hills towards the west, the Palni hills toward the southeast, and the Eravikulam, High Wavy and other ranges towards the south. 

 

 

A number of protected areas span this region, including the Indira Gandhi Wildlife Sanctuary (987 km²), Eravikulam Wildlife Sanctuary (97 km²), Chinnar Wildlife Sanctuary (90 km²), Parambikulam Wildlife Sanctuary (274 km²) and several reserved forests. This region is also contiguous with reserved forests and protected areas further to the west and east. Thus the Anamalai hills, covers a large forested region of great significance for conservation in the Western Ghats. The Anamalai hill range is a vast expanse of undulating and rugged terrain spreading across the states of Kerala and Tamil Nadu. The highest peak in south India, Anaimudi 2,695 m is also a part of the range. A large proportion of this range has been set aside as protected and reserved forests due to its importance as a base for natural resources and also as the watershed of many major rivers and minor streams originating from these hills. 

 

 

Grass Hills and Karian Shola National parks are located within the larger Indira Gandhi Wildlife Sanctuary (earlier known as the Anamalai Wildlife Sanctuary, 987 km², 10° 12' N to 10° 35' N and 76° 49' E to 77° 24' E). The altitude within the sanctuary ranges from 220 m in the foothills along the northern fringes to 2,513 m atop Tanakamalai in the Grass Hills at the southern portion of the reserve. The region is drained by perennial rivers such as the Konalar, Varagaliar, Karuneerar, Chinnar and Amaravathi. A number of reservoirs (Aliyar, Upper Aliyar, Kadamparai, Upper and Lower Nirar, Thirumurthy and Parambikulam), are at least partly within the Indira Gandhi Wildlife Sanctuary. The Eravikulam National Park occupies the region variously termed as the High Ranges or the Kannan Devan hills forming a contiguous stretch of mountains to the south. This 90 km² National Park contains in the surrounding landscape other key areas for conservation, including the Mankulam Range, the Mannavan Shola in Marayoor range and three recently established National Parks, all in Kerala State. It is also contiguous with the Chinnar Wildlife Sanctuary comprising of lower hills on the eastern rain shadow region, with typically dry forest formations. Different parts of the region experience widely varying annual rainfall, from less than 700 mm in the eastern reaches to over 4,000 mm in the higher and western reaches, mostly falling during the southwest monsoon. It enjoys a tropical to sub-tropical climate due to the effects of elevation, with temperatures between 5°C and 35°C, with occasional frost in winter in the uppermost reaches. Most of the nominated sites contain typical high altitude shola-grassland vegetation. 

 

 

 

Nilgiri Sub-Cluster (with Six Site Elements) 

 

 

 

The Nilgiri region consists of a landscape extending from the north-west of the Palghat Gap, a prominent break in the main Western Ghats ridgeline, up to the Mukurti region of the Nilgiri Plateau. This region spans a wide elevation range from around 50 m in the New Amarambalam Reserved Forest to nearly 2500 m in the Mukurti National Park. By virtue of its extremely variable aspect, rainfall regimes also vary tremendously although most of the precipitation occurs during the few months of the southwest monsoon. Pudur in the rainshadow areas of Attapadi Range receives around 800 mm annually, whereas in the Neelikal area of Silent Valley National Park, annual precipitation exceeds 5000 mm. As a direct consequence of these physiographic and climatic gradients, the vegetation in the region varies from dry Euphorbia scrub in parts of the Attapadi range, deciduous and evergreen forests in parts of Kalikavu and New Amarambalam to shola-grasslands that dominate the main Western Ghats crestline around Mukurti. This region also represents the origin of several important west- and east flowing rivers. Major tributaries of the Rivers Chaliyar, Bharathapuzha, Kuntipuzha, Bhavani and Siruvani originate in this area, which constitutes critical catchments for many irrigation and hydroelectric dams downstream. Together with the adjacent protected areas of the Nilgiri Biosphere Reserve, this sub-cluster constitutes a largely secure forest complex of over 6,000 km², which is one of the globally most significant conservation areas for highly threatened species such as the Asian elephant, tiger and gaur, besides dozens of endangered species in other taxa. 

 

 

 

Talacauvery Sub-Cluster (with Six Site Elements) 

 

 

 

All site elements in the Talacauvery region are situated in Karnataka state except the Aralam Reserved Forest (RF) in Kerala state. Pushpagiri Wildlife Sanctuary (92.65 km²) has dense evergreen and semi-evergreen vegetation, with shola-grassland in areas of higher elevation. The steep terrain of the Sanctuary has resulted in scenic waterfalls along its many mountain streams. Altitude varies from 160 to 1,712 m, the highest point being the Pushpagiri Peak in the north of the park. Temperatures range from 10-38°C, with annual rainfall exceeding 6,500 mm. Brahmagiri Wildlife Sanctuary (181.29 km²) also consists of evergreen and semievergreen forests in the lower-lying areas with shola-grassland habitat in the higher altitudes. 

 

 

The eastern tip of the Sanctuary is adjacent to the north-western boundary of Rajiv Gandhi (Nagarahole) National Park, separated by a narrow strip of coffee plantations. The highest point in the Sanctuary is the Brahmagiri Peak on the south-eastern boundary, while elevation varies between 65 m and 1,607 m. Temperatures range from 5°-32° C, and mean annual rainfall varies from 2,500 mm to 6,000 mm. Talacauvery Wildlife Sanctuary (105.01 km²) is located in the Kodagu (Coorg) district of Karnataka. Its forests are predominated by tropical evergreen forests. It is named after Talacauvery the origin of the Cauvery River which lies on the eastern edge of the Sanctuary. Altitudinal and temperature ranges are 64-1,659 m and 10°-35° C, respectively. Annual rainfall is above 6,500mm. 

 

 

The areas between Talacauvery and Pushpagiri sanctuaries have been excluded from the proposed area mainly due to the fragmentation and habitat degradation caused by the Mangalore-Madikeri road. There is no natural forest cover for about 2 km on either side of this road. There are some teak and rubber plantations near the road. 

 

 

 

Kudremukh Sub-Cluster (with Five Site Elements) 

 

 

 

The Kudremukh National Park, Someshwara Wildlife Sanctuary, and surrounding Reserved Forests of Someshwara, Agumbe and Balahalli of Karnataka state are situated centrally in the Western Ghats Biodiversity Hotspot. Kudremukh National Park has one of the most beautiful landscapes in the Western Ghats, encompassing evergreen, semi-evergreen and grasslandshola habitat characteristic of high altitude Western Ghats regions. Altitude varies from 120 to 1,892 m, the highest point being the Kudremukh Peak in the south of the Park. The Park has average temperatures ranging between 17° C and 28° C. Annual rainfall varies from 1,778 mm to 6,350 mm, with an average of 4,000 mm and a maximum recorded rainfall of 10,000 mm in 1994. The topography is mountainous with a central ridge running north-south through the Park. The Park is dotted with crystal-clear streams and picturesque waterfalls. Kudremukh National Park is flanked by coffee and tea estates on the north and east, whereas on the west, the land drops down to the Arabian Sea. In the northwest is a forest corridor that connects the Park with the Someshwara Wildlife Sanctuary. The Sanctuary, named after the famous Someshwara Temple located within it, and the adjoining 105.3 km² of Reserved Forest are predominantly evergreen forests, along with semi-evergreen vegetation. These Reserved Forests are in the process of being included within the Sanctuary. Elevation ranges from 75-870 m and the temperature varies between 20° C and 30° C, with an average annual rainfall of 6,000 mm. 

 

 

 

Sahyadri Sub-Cluster (with Four Site Elements) 

 

 

 

The Western Ghats of Maharashtra, locally known as Sahyadri lie roughly between 15° 60' and 20° 75' N and between 72° 60' and 74° 40' E, covering about 52,000 km² area from Daman to Terekhol creek. The hills vary in height from 20 m to 2,000 m. As part of the Deccan Plate, this region has Gondwanaland origins. The Sahyadri sub-cluster includes the middle and upper elevation biomes of the northern Western Ghats, contain geologically and biologically unique formations. 

 

 

The windward western slopes of the region receive more than 2,500 mm of rainfall annually, particularly during south-west monsoon (June-September). Three large rivers, the Godavari, Koyna and Krishna carry the rainfall from the monsoon rains eastward into the drier Deccan Plateau. The mountain range ascends abruptly on the western side from near sea level to the crest line and descends more gradually to 500 m on the Deccan plateau. The deeply dissected terrain produces localized variations in rainfall and habitat types and creates Hotspots of endemism by limiting species distribution. 

 

 

The presence of numerous barren rocky lateritic plateaus locally called sadas is the unique feature of the Sahyadri. These plateaus possess very characteristic herbaceous ephemeral vegetation. The Kas Plateau is one of the important sadas located in Satara district, at an elevation of around 1,213 m. The rainfall received is between 2,000 and 2,500 mm annually. Of the total area of 1,792 hectares under the Kas plateau, 1,142 hectares is recorded as Government Forest. 

 

 

To the west and south of the Kaas plateau, lies the Koyna Wildlife Sanctuary spanning an altitudinal range of 600 m to 1, 100 m. The rivers Koyna, Kandati and Solashi, originating in the Western Ghats, span the sanctuary. It forms and protects the catchment of river Koyna and the reservoir Shiv Sagar formed by the dam on it. To the south lies, Chandoli National Park (earlier a Wildlife Sanctuary declared in 1985) located at the junction area of four districts, Sangli, Kolhapur, Satara and Ratnagiri of Western Maharashtra. It spreads along the crest of the Sahyadri Range of the Western Ghats and lies between Koyna and Radhanagari Sanctuary. It forms and protects many perennial water channels, water holes and the Vasant Sagar reservoir. The altitude of national park ranges from 589 m to 1,044 m. 

 

 

The Radhanagri Wildlife Sanctuary, the first wildlife sanctuary of Maharashtra, was notified in 1958. It lies at the southern end of the Sahyadri sub-cluster and is popularly known as ‘Bison Sanctuary as the ‘Indian Bison’ or gaur (Bos gaurus) is the flagship species of the area. It consists of the catchment area of the two major reservoirs namely Rajarshi Shahu Sagar and Laxmi Sagar in Radhanagari Taluka of Kolhapur district. Bhogavati, Dudhganga, Tulshi, Kallamma and Dirba are among some of main rivers those flows through the sanctuary area, which drain out into the River Krishna, a major river of the Deccan Peninsula. Radhanagari Wildlife Sanctuary contains some of the tropical evergreen forests typical of the northern Western Ghats.

 

 

 

 

 

 

 

 

 

 

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