A Biodiversity Hotspot of India: Western Ghats
Due to the different types of human activities such as Development, urbanization, pollution a huge number of animals threatened by their habitat loss. The species (including human) are the building blocks of life-support systems for this planet. However, our planet faces a major crisis of the species proportion in terms of Ecology. As a result, throughout the planet many species are going extinct at fastest rate since the mass extinction of the dinosaurs.
The term biodiversity means, to the variety and variability of animals and plants in this planet. The land biodiversity is usually greater near the equator due to the high productivity. Now the concept of biodiversity hotspot is a particular geographic region, which plays a significant role as biologically rich and deeply threatened with human destruction. This is a serious concern we must protect these places where biodiversity lives.
A British environmentalist specialising in biodiversity, Norman Myers wrote about the concept of 'protecting the nature' in his article "The Environmentalist" (1988). In 1990, that article was revised after thorough analysis by Myers and others and named as "Hotspots: Earth’s Biologically Richest and Most Endangered Terrestrial Ecoregions" which published in the Nature journal. Conservation International adopted the idea of protecting these incredible places and endangered species, which can have immense impact in securing our biodiversity.
After that, the 36 regions in the planet are declared as biodiversity hotspots. The hotspots represent just 2.4% of Earth’s land surface, but they support more than half of the world’s plant species as endemics i.e., those found nowhere else on the planet and nearly 43% of bird, mammal, reptile and amphibian species as endemics. A hotspot, in other words, is irreplaceable.
Based on Myers’s 2000 edition of hotspot-map a region will consider to qualify, as a biodiversity hotspot should meet two strict criteria:
- It must have at least 1,500 vascular plants as endemics.
- It has to have lost at least 70% of its primary vegetation
The eastern Himalaya and Western Ghats of India are consider as 2 biodiversity hotspots, which have faced with tremendous population pressure. The forests of the Western Ghats and Himalaya have been dramatically impacted by the demands for timber and agricultural land. I am writing here on the threaten species of Western Ghats.
The Western Ghats, aka Sahyadri, are a mountain range that starts from Songadh town of Gujarat, travers the Indian states Maharashtra, Goa, Karnataka, Kerala and ending at the southern tip of India Swamithope, Tamil Nadu.
There are lots of Dravidian derivatives for the word ghat such as in Kannada gaati and ghatta means mountain range, in Tulu gatta means hill or hillside, Tamil kattu (side of a mountain, dam, ridge, causeway) and ghattam in Malayalam (mountainous way, riverside and hairpin bends) and Telegu katta and gattu means dam and embankment.
Based on the Geophysical evidence of Western Ghats it indicates that the west coast of India came into being somewhere around 100 to 80 may after it broke away from Madagascar. After the break-up, the western coast of India would have appeared as an abrupt cliff of Basalt predominant rock with thickness of 3 km .
Other rock types found are charconites, granites, khondalites, leptynites with detached occurrences of crystalline limestone, iron ore, dolomites and anorthosite. The bauxites are also found in the southern hills.
It covers the total area of 140,000 km2 and 1,600 kilometres of length which parallel to the western coast of the Indian Peninsula. It is a UNESCO World Heritage Site and according to that the Western Ghats are older than the Himalayas.
Unfortunately the Sahyadri range is one of the world's ten "hottest biodiversity hotspot" and has over 7402 species of flowering plants, 1814 species of non-flowering plants, 139 mammal species, 508 bird species, 179 amphibian species, more than 6000 insects species and 290 freshwater fish species. At least 325 globally threatened species occur in the Western Ghats.
Till before the British era the Western Ghats was the impenetrable jungle due to dense rain forest and provided wild food, natural habitats for native tribal people. From 1860 to 1950 during the British regime the Western Ghats has been severely damaged due to human activities specially tea, coffee and teak plantations. As a result the endemic (native) species were adversely affected and tend to be lost faster than other species.
The area covers 5% of India’s land ; 4,000 of 15,000 species of higher plants in India found here and among those 1800 species are endemics. This mountain range is the home to at least 84 amphibian species, 16 bird species, and 1,600 flowering plants which are not found elsewhere in the world. In 1988 this area was declared as an ecological hotspot through the efforts of ecologist Norman Myers.
Of the 7,402 species of flowering plants occurring in the Western Ghats, 5,588 species are endemic or native and 376 are exotics naturalised. The cultivated and ornamentals number of plants are 1,438 species.
The Western Ghats are home to thousands of animal species including at least 325 globally threatened species.
There are at least 139 mammals species, among them 16 endemic mammals, 13 are threatened. The threatened species are the critically endangered Malabar large-spotted civet, the endangered lion tailed macaque, Nilgiri tahr or Nilgiri ibex, Bengal tiger, Indian elephants, Indian leopard, Nilgiri langur and Indian bison (gaur). These mountain range is an important part of Project Elephant and Project Tiger reserves. The largest population of tigers outside the Sundarbans is in the Western Ghats.
|Black Panther from Western Ghats|
There are at least 16 species of endemic birds are from Western Ghats including the endangered Rufous-breasted laughing thrush, the vulnerable Nilgiri wood pigeon, White-bellied short wing and broad-tailed grass bird, Nilgiri flycatcher, White-bellied blue flycatcher, Nilgiri pipit, Malabar Grey Hornbill, Crimson-backed sunbird.
|Rufous-breasted laughing thrush|
|Malabar Grey Hornbill|
Western Ghat is the endemic region for shield-tailed snakes family like Melanophidium, Plectrurus, Teretrurus, Rhabdops and so on, the venomous snakes such as the striped coral snake, the Malabar pit viper, several reptile genera including the Kerala or forest cane turtle, lizards like Salea, Ristella, Kaestlea. The region has a significant population of the vulnerable mugger or marsh crocodile.
|Malabar pit viper|
|Striped Coral Snake|
The rainforests of the Western Ghats are diverse and unique for the Amphibians, with more than 80% of the 179 amphibian species being endemic to this mountain range. In 2003 the endangered purple frog was discovered here. Several genera of frogs such as, bicolored frog or Malabar frog, Micrixalus, Indirana are endemic to this region. Among the endemic genera of toads are Pedostibes, Ghatophryne; arboreal frogs such as Ghatixalus, Mercurana and Beddomixalus. In 2005, some new frog species were described from the Western Ghats.
|Bicolored frog or Malabar frog|
The southern part of the Western Ghats is higher in fish count than the northern part of Western Ghats. The highest fish richness is in the Chalakundy river, which alone holds 98 species. Other rivers with high species numbers include the Periyar,Pamba and upstream tributaries of the Krishna, Kaveri, Bhavani.
As of 2004, in Western Ghat 253 freshwater and 35 brackish or marine water fish species were listed. There are 118 endemic species, including 13 genera entirely restricted to the Western Ghats, those are Betadevario, Dayella, Haludaria etc. The lakes of western ghat region is home to several brilliantly coloured ornamental fishes like the Dension barb or red line torpedo, melon barb, several species of Dawkinsia barbs, zebra loach, horabagrus catfish, dwarf pufferfish and dwarf Malabar pufferfish.
According to the International Union for Conservation of Nature (IUCN), 97 freshwater fish species from the Western Ghats were considered threatened in 2011, including 12 critically endangered, 54 endangered and 31 vulnerable.
|Dension barb or red line torpedo|
|Dwarf Malabar pufferfish|
There are approximately 6,000 insect species can be found in Western Ghat, including 334 types of Western Ghats butterfly. The Western Ghats are home to 174 species of odonates and 69 of those are endemics. Most of the endemic odonate are closely associated with rivers and streams, while the non-endemics typically are generalists. In Western Ghats several species of leeches are also found.
In Western Ghats total 77 species of freshwater molluscs (52 gastropods and 25 bivalves) have been recorded, including 28 endemics. According to the IUCN, 4 species of freshwater molluscs are considered endangered and 3 are vulnerable.
The Government of India has established many protected areas including 2 biosphere reserves, 13 national parks to restrict human access, several wildlife sanctuaries and lots of reserves forests to protect specific endangered species. All are managed by the forest departments of their respective state to preserve some of the ecologic regions still undeveloped.
In 2006, India applied to the UNESCO Man and the Biosphere Programme for the Western Ghats to be listed as a protected World Heritage Site. In 2012, 46 protected areas were declared as World Heritage Sites, such as Periyar Tiger Reserve, Bandipur National Park, Nilgiri biosphere Reserve, Kaas plateau, Kudremukh national Park etc.