India has about 8 percent of the world’s biodiversity on 2 percent of the earth’s surface, making it one of the 12 mega-diversity countries in the world. Of about 1.75 million species globally identified, around 1,26,188 species have been reported so far from India. The species recorded include flowering plants (angiosperms), mammals, fish, birds, reptiles and amphibians, constituting about 17.3 percent of the total, whereas fungi and insects make up nearly 60 percent of India’s bio-wealth. This diversity can be attributed to the great variety of natural ecosystems due to the varied physical and climatic features found in India.
India ranks tenth in the world both in respect of richness of flowering plants (17,500 spp.) and mammals (350 spp.) and fourth in Asia in plant diversity. India is also a centre of crop diversity, a homeland of as many as 167 species of crops and 320 species of wild crop relatives.
The country has 10 different bio geographic zones and 26 biotic provinces gifted with unique and rare species of flora and fauna.
There are certain terms that we must know to understand the status of and problems faced by wildlife.
Endemic: When a species is found only in a particular geographical region because of its isolation, soil and climatic conditions it is said to be endemic.
Extinct: Permanent disappearance of a species in the wild after repeated searches of known or likely areas where they may occur.
Endangered: A species in danger of becoming extinct.
Threatened: A species that will become endangered if its present condition in the wild detoriorates.
Rare: A species that is not yet threatened with extinction, but is in need of close monitoring.
Vulnerable: A species experiencing a decline in the number of its population.
Schedule I animal: An animal specified in Schedule I of the Wildlife (Protection) Act, 1972 which is endangered or threatened or rare.
IUCN: International Union for Conservation of Nature and Natural Resources.
The Eastern Himalayas and the Western Ghats are 2 of the 18 recognized hotspots of the world. Hotspots generally refer to the areas rich in general diversity, high degree of endemism and higher incidence of endangered and threatened species of flora and fauna.
The Eastern Himalayas are recognized as the ‘Cradle of Speciation’ due to their rich diversity of primitive flowering plants. 63 percent of the genera of the Indian land mammals, more than 60 percent of Indian birds, two endemic genera of lizards, 35 endemic reptilian species, including two turtle and 68 amphibian species of which 20 are endemic, are found in this region.
The Western Ghats run for approximately 1,500 km. along the west coast of India. They cover only 5 percent of India’s land surface, but the region has 490 arborescent taxa, of which as many as 308 are endemic. 245 species of orchids belonging to 75 genera are found here, of which 112 species in 10 genera and about 1,500 dicotyledonous plants are endemic to this region.
As many as 315 species of vertebrates belonging to 22 genera are endemic, including 12 species of mammals, 13 species of birds, 89 species of reptiles, 87 species of amphibians and 104 species of fish.
The rich faunal and floral diversity in these regions are listed as threatened. Nearly 235 species of endemic flowering plants are considered endangered.
The Lion tailed macaque, Niligiri Langur, Nilgiri tahr, flying squirrel and Malabar gray hornbill of this region are recognized as rare fauna.
Today, India’s biodiversity is in jeopardy. Due to various reasons, many wild species are disappearing rapidly. An incalculable number of species are already gone forever, and a large percentage of the rest are threatened with extinction. In almost all cases, the threats to wildlife can be traced to human activities. Today, with the population explosion, more and more land is being cleared for agriculture, habitation and other developmental projects.
The tropical forests are home to the largest number of animals and plants. It is estimated that, since Independence, the country has lost about 4,696 million hectares of forest land for non-forest purposes such as cultivation, river valley projects, establishment of industries and townships, illegal encroachments and laying of roads.
Natural and manmade forest fires also devastate vast tracts of forests and adversely affect regeneration of new species.
The mangroves swamps that are the natural vegetation of the wetlands are located in the alluvial deltas of Ganga, Mahanadi, Godavari, Krishna and Kaveri rivers and on the Andaman and Nicobar group of Islands. They occupy 6,700 sq. km., making up about 7% of the world’s mangroves. Their elevated root systems are host to 105 species of fish, 20 kinds of shellfish, 229 crustacean species and 117 species of migratory and residential birds that reside in the canopy. The Sunderban mangroves are also the home of the Royal Bengal tiger.
Growing along the coastline, mangroves are a natural wind belt and prevent erosion of the coast, control sealevel rise, provide long-term community stability and act as barrier against the direct force of storms and tsunamis.
The wetlands and hence the mangroves are being ruined by siltation due to soil erosion, agricultural run off, aquaculture, fuelwood extraction, diversion of fresh water for irrigation and indiscriminate construction and tourism. This sounds a death knell for hundreds of species dependent on the wetlands.
Corals are living organisms which, in a community, are called coral reefs. Coral reefs are the largest, oldest, most diverse and most beautiful communities of plants and animals. They have become seriously damaged or at risk. The coral reef cover in Indian waters is roughly estimated as 19,000 sq.km. and has an impressive diversity of about 200 coral species belonging to 71 genera. The richest is that of the Andaman and Nicobar Islands which alone harbours 179 species.
Coral reefs protect the coastline from erosion and provide a home for a vast variety of plants and animals. Approximately 25% of all marine life, i.e. about 1 million species, are associated with coral reefs. Habitat destruction is the main threat faced by coral reefs. Lying close to the shore they are subjected to sewage, industrial effluents and hot water from cooling systems. Corals are also under threat as they are used as a raw material in cement factories, exploited as antipatharians and used to make jewellery and commercially exploited for aquarium fish.
Two important species have become extinct in India in the 20th century. The pink-headed duck was last seen in the wild in 1935 and the cheetah in 1949. This bird was largely restricted to the tall terai grasslands. The conversion of the grasslands to agricultural fields may have been one of the major reasons for the disappearance of this ground nesting species.
The cheetah was an inhabitant of open savannah forests and grasslands. Again, the loss of its habitats made sightings of the cheetah unusual even in the 19th century, till it disappeared totally from 20th century India.
India is home to nine species of hornbills and the northeastern region has the highest diversity of hornbill species in the country, with five hornbill species found there. Three of them are endemic to this region. They are the Wreathed hornbill, Brown hornbill, Rufous-necked hornbill. The other two species, the great Indian hornbill and the Oriental pied hornbill also occur in other parts of India. Except the Oriental pied hornbill, all the others are listed under Schedule I of the Wildlife (Protection) Act, 1972. The Rufous-necked hornbill is listed as ‘rare’ in the IUCN Red Data Book (1990). Hunting and habitat clearance have threatened the bird. Being a key seed disperser, the survival of the hornbill is necessary for forest survival and restoration.
Kites and vultures are the commonest birds of prey found near human habitations. They feed on garbage and dead animals and help mankind in keeping his surrounding clean and healthy. By feeding on highly decomposed carcasses they prevent the outbreak of infectious diseases. The excreta of vultures contain guanine, which is a good fertilizer. These are now under threat because of destruction of nesting trees and bio-magnification of pesticides. According to IUCN, Pariah kites and white-backed vulture are recognized as ‘rare’ species.
Numbers of vulture have fallen by 90 percent and their disappearance is causing great difficulties for both the Parsi community, who rely on them to dispose of their corpses and village Hindus, who depend on them to consume the carcasses of dead cattle.
The Lesser Florican which is on the verge of extinction, arrives in the grasslands of Western Madya Pradesh and Saurashtra in Gujarat with the first showers of the monsoon. The whole breeding cycle is so closely interlinked with the availability of suitable grasslands and the onset of the monsoons that the entire survival system of the species has become fragile.
Hoolock Gibbon is found in the rainforests of Arunachal Pradesh, Assam and parts of Nagaland. Their loud whooping early in the morning is heard over a considerable distance and is one of the most evocative sounds of the jungle. But the gibbon, like many other apes throughout the world, is also facing a stiff challenge to its survival, due to pressure for land and timber.
The tiger’s domain ranges over most of the Indian subcontinent. The tiger is at home in a variety of environmental situation from the high altitude, cold, coniferous Himalayan forests to the steaming mangroves of Sundarbans delta, swampy reedlands of the terai, the lush wet evergreen forests of northeast and the south and the scrub-thorn arid forests of Rajastan.
The tiger is the best indicator species of an ecosystem. It is the ultimate consumer in the complex food web in many of the forest ecosystems of India. Among the terminal carnivorous animals of an ecosystem, the tiger stands at the head. Conservation of tiger in its natural environment can be achieved only by total conservation of the wilderness based on an ecosystem approach. That is the reason why it is stated that the status of tiger in India is the index of success, as a whole, in the conservation of wildlife.
The distribution of wild elephants in India is limited to South, Central, North and North-East India. Elephants are indicators of ecological health. Wherever elephants live, they provide a good habitat for the associated species such as sambar, spotted deer, the barking deer and so on, which in turn keep the predators like tiger or leopard happy. Elephants are mainly hunted for their tusks. This has made the species endangered.
Even the lion has become a rare animal in India. Lions are restricted to Gir forest. The major hazard for the lion, as for the other species threatened with extinction in India, is habitat loss.
Ecosystem services are in a sense the variety of benefits derived from different types of ecosystems as a result of interaction between biotic and abiotic components.
The ecosystem comprises of each and every component within it, ranging from the smallest microbe to the largest tree, soil, nutrients, air and water. In a healthy ecosystem, all these components are intact and exist in perfect harmony – what we call ecological balance.
Ecological services include numerous invisible but essential services such as
Conserving the ecosystem is to conserve each and every component in it and conserving a species requires the conservation of its habitat or the ecosystem it is used to.
About 70 % of the Indian population depend on land-based occupations depending on forests, wetlands and marine habitats. Around 10,000 species of plants and a few hundred animal species are involved in this direct relationship between biodiversity and livelihood.
According to scientists, the largest use by communities of ecosystem resources is for maintaining health security of human, livestock and plants. Around 8000 species plants and a few hundred species of animals provide for this.
The economic value of ecosystem services and components of bio diversity amounts to Rs. 1650 billion, which is around 1.8 times more than the world’s GNP. This includes the value of biodiversity in agriculture, livestock, fisheries, medicinal value of marine resources, value of micro organisms in pharmacenters, value of wild medicinal plants, import and export of bio resources and eco tourism. The pharmaceutical industry alone depends to a great extent wild resources, estimated at around 12000 lakh rupees a year, and around 660 wild species are involved in all India trade.
Human beings constitute only one of the millions of species that inhabitat the earth. Each species is unique and was created as a consequence of evolutionary processes without human intervention. Therefore every species has a natural right to exist.
Nature is a major source of inspiration and subject of scientific thought. Modern sciences study physical, chemical and biological aspects of biodiversity. The indigenous sciences such as Krishi-shastra, Ayurveda, Vriksh-Ayurveda and so on provide examples of the scientific values of wildlife.
In Indian languages, the two key words, which point to the central relationship between nature and culture, are the words ‘Pra-kruti’ and ‘Sams-kriti’. Whereas nature (Prakriti) is seen as an unmodified (Pra) life process (Kriti), culture (Samskriti) is described as the modified (Samskar) nature (Kriti). A great diversity of plants and animals have been used for religious and cultural purposes.
Wildlife has an aesthetic value that is experienced by human beings when they are in natural surroundings. The aesthetic function of nature has a value reflected in the creation of millions of small home gardens, community gardens and botanical gardens, zoos, aquariums and so on.
Considering the importance of flora and fauna, there are major national and international efforts to protect and conserve the rich biodiversity and endangered species of wildlife and flora.
Source : CPR Environmental Education Centre, Chennai
Last Modified : 2/13/2020
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