Archive for the 'North Bengal' Category

Indian Rainforests

An article by Mohan Pai

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The Indian Rainforests


Rainforests – the Lungs of the Planet Earth
Tropical rainforests are vital to the global ecosystem and human existence. They are a world like no other and are unparalleled in terms of their biological diversity. Tropical rainforests are a natural reservoir of genetic diversity which offers a rich source of medicinal plants, high-yield foods, and a myriad of other useful forest products. They are an important habitat for migratory animals and sustain as much as 50 percent of the species on Earth, as well as a number of diverse and unique indigenous cultures. Tropical rainforests play an elemental role in regulating global weather in addition to maintaining regular rainfall, while buffering against floods, droughts, and erosion. They store vast quantities of carbon, while producing a significant amount of the world’s oxygen. Rainforests once covered 14% of the earths surface and even though they now only cover 6% of the earth, they are home to almost half of the worlds population of mammals, amphibians, reptiles, insects, bird life and plant life.
Tropical rainforests are located in a band around the equator (Zero degrees latitude) in the area between the Tropic of Cancer (23.5° North latitude) and the Tropic of Capricorn (23.5° South latitude).This 3,000 mile (4800 kilometres) wide band is known as the ‘tropics’.

The equator is a line that circles the centre of our global world and is situated halfway between the north and south poles. Temperatures at the equator are high. These high temperatures cause accelerated evaporation of water, which results in frequent rain in rainforests in the tropics.

World Rainforests
 
Tropical rainforests are found between latitudes 10° N and 10° S. This includes the Amazon Basin of South America, the Zaire Basin of Africa and the islands and peninsulas of South-east Asia.In Southeast Asia, the tropical rainforests are found in India, Bangladesh, Sri Lanka, Malaysia, Brunei, Indonesia, Burma and Papua New Guinea. The rainforests found in India, Bangladesh and Sri Lanka are in small patches and strips, while on the other hand, Indonesia contains one-tenth of the world’s rainforest and 40% of all Asian rainforests! However sadly, as Indonesia is progressing further into modernisation, it is losing its rainforests to commercial logging and human settlements. Malaysia too has lost about two third of its lowland forest to plantations. On a brighter side, Papua New Guinea still has areas of rainforest yet to be disturbed, due to its mountainous terrain. Papua New Guinea is home to many amazing animals, one being the largest butterfly in the world; the Queen Alexandra’s birdwing. Its wing span can reach up to 10 inches wide!
Although they cover less than 2 percent of Earth’s surface, they house an estimated 50 percent of all life on the planet. The immense numbers of creatures that inhabit the tropical rainforests are so great—an estimated 50 million species— they are almost incomprehensible. The sheer range of numbers alone suggests the limited extent of our knowledge of these forests. For example, whereas temperate forests are often dominated by a half dozen tree species or fewer that make up 90 percent of the trees in the forest, a tropical rainforest may have more than 480 tree species in a single hectare (2.5 acres). A single bush in the Amazon may have more species of ants than the entire British Isles. This diversity of rainforests is not a haphazard event, but is the result of a series of unique circumstances.
Layers
A tropical rainforest is typically divided into four main layers, each with different plants and animals adapted for life in that particular area: the emergent, canopy, understory, and forest floor layers.

Emergent layer
The emergent layer contains a small number of very large trees called emergents, which grow above the general canopy, reaching heights of 45-55 m, although on occasion a few species will grow to 70-80 m tall. They need to be able to withstand the hot temperatures and strong winds in some areas. Eagles, butterflies, bats, and certain monkeys inhabit this layer.

Diagram: Coutesy Animal Corner
 

Canopy layer
The canopy layer contains the majority of the largest trees, typically 30-45 m tall. The densest areas of biodiversity are found in the forest canopy, a more or less continuous cover of foliage formed by adjacent treetops. The canopy, by some estimates, is home to 50 percent of all plant species, suggesting that perhaps half of all life on Earth could be found there. Epiphytic plants attach to trunks and branches, and obtain water and minerals from rain and debris that collects on the supporting plants. The fauna is similar to that found in the emergent layer, but more diverse. A quarter of all insect species are believed to exist in the rainforest canopy. Scientists have long suspected the richness of the canopy as a habitat, but have only recently developed practical methods of exploring it. As long ago as 1917, naturalist William Beebe declared that “another continent of life remains to be discovered, not upon the Earth, but one to two hundred feet above it, extending over thousands of square miles.” True exploration of this habitat only began in the 1980s, when scientists developed methods to reach the canopy, such as firing ropes into the trees using crossbows. Exploration of the canopy is still in its infancy, but other methods include the use of balloons and airships to float above the highest branches and the building of cranes and walkways planted on the forest floor. The science of accessing tropical forest canopy using airships, or similar aerial platforms, is called dendronautics.

Understory layer
The understory layer lies between the canopy and the forest floor. The understory (or understorey) is home to a number of birds, snakes, and lizards, as well as predators such as jaguars, boa constrictors, and leopards. The leaves are much larger at this level. Insect life is also abundant. Many seedlings that will grow to the canopy level are present in the understory. Only about 5 percent of the sunlight shining on the rainforest reaches the understory. This layer can also be called a shrub layer, although the shrub layer may also be considered a separate layer.

Forest floor
The forest floor, the bottom-most layer, receives only 2 percent of sunlight. Only plants adapted to low light can grow in this region. Away from riverbanks, swamps, and clearings
where dense undergrowth is found, the forest floor is relatively clear of vegetation because of the low sunlight penetration. It also contains decaying plant and animal matter, which disappears quickly due to the warm, humid conditions promoting rapid decay. Many forms of fungi grow here which help decay the animal and plant waste. It takes up to 20 minutes for rain to actually touch the ground from the trees. Forest floor – Mahadayi Valley, Karnataka.
Because of the ample solar energy, tropical rainforests are usually warm year round with temperatures from about 72-93F (22-34C), although forests at higher elevations, especially cloud forests, may be significantly cooler. The temperature may fluctuate during the year, but in some equatorial forests the average may vary as little as 0.5F (0.3C) throughout the year. Temperatures are generally moderated by cloud cover and high humidity.
 
PRECIPITATION

An important characteristic of rainforests is apparent in their name. Rainforests lie in the intertropical convergence zone where intense solar energy produces a convection zone of rising air that loses its moisture through frequent rainstorms. Rainforests are subject to heavy rainfall, at least 80 inches (2,000 mm), and in some areas over 430 inches (10,920 mm) of rain each year. In equatorial regions, rainfall may be year round without apparent “wet” or “dry” seasons, although many forests do have seasonal rains. Even in seasonal forests, the period between rains is usually not long enough for the leaf litter to dry out completely. During the parts of the year when less rain falls, the constant cloud cover is enough to keep the air moist and prevent plants from drying out. Some neotropical rainforests rarely go a month during the year without at least 6″ of rain. The stable climate, with evenly spread rainfall and warmth, allows most rainforest trees to be evergreen—keeping their leaves all year and never dropping all their leaves in any one season. Forests further from the equator, like those of India, Thailand, Sri Lanka, and Central America, where rainy seasons are more pronounced, can only be considered “semi-evergreen” since some species of trees may shed all of their leaves at the beginning of the dry season. Annual rainfall is spread evenly enough to allow heavy growth of broad-leafed evergreen trees, or at least semi-evergreen trees. The moisture of the rainforest from rainfall, constant cloud cover, and transpiration (water loss through leaves), creates intense local humidity. Each canopy tree transpires some 200 gallons (760 liters) of water annually, translating to roughly 20,000 gallons (76,000 L) of water transpired into the atmosphere for every acre of canopy trees. Large rainforests (and their humidity) contribute to the formation of rain clouds, and generate as much as 75 percent of their own rain.
The Amazon rainforest is responsible for creating as much as 50 percent of its own precipitation. Deforestation and climate change may be affecting the water cycle in tropical rainforests. Since the mid-1990s, rainforests around the world have experienced periods of severe drought, including southeast Asia in 1997 and 2005 and the Amazon in 2005. Dry conditions, combined with degradation from logging and agricultural conversion, make forests more vulnerable to wildfire.

Rainforests Waters
Tropical rainforests have some of the largest rivers in the world, like the Amazon, Madeira, Mekong, Brahmaputra, Negro, Orinoco, and Zaire (Congo), because of the tremendous amount of precipitation their watersheds receive. These mega-rivers are fed by countless smaller tributaries, streams, and creeks. For example, the Amazon alone has some 1,100 tributaries, 17 of which are over 1,000 miles long. Although large tropical rivers are fairly uniform in appearance and water composition, their tributaries vary greatly. Many tropical rivers and streams have extreme high and low water levels that occur at different parts of the year. In addition to rivers, rainforests have conventional, free-standing lakes and so-called oxbow lakes, formed when a river changes course. These lakes are home to species adapted to the quiet, stagnant conditions. Tropical waters, whether they be giant rivers, streams, or oxbow lakes, are almost as rich in animal species as the rainforests that surround them. But they, too, are increasingly threatened by human activities, including pollution, siltation resulting from deforestation, hydroelectric projects, and over-harvesting of resident species.

Forest – the mother of rivers

There is an umbilical connection between healthy forests and water regimes. Forests are nurseries and cisterns for our life giving rivers. Forest areas give birth to all the major and minor rivers. Most of the rivers spring from some unknown forests. Because of the slope the rain water cannot stay to soak into the earth, it flows downhill rapidly taking some of the earth with it This run-off on the hillsides will only be halted, and water will percolate into the earth where there is a good tree cover. In fact a forest “traps” rainwater and channels it into underground streams.
 
World’s Largest Pharmacy

Medicinal plants and herbs which are in great demand by Pharmaceutical MNCs e.g. Mappia foetida used for the treatment of ovarian colon cancers. The tree is the richest source of Camptothetician (CPT) used in the treatment of these cancers.

Tropical rainforests are called “the world’s largest pharmacy” because of the large amount of natural medicines discovered in rainforests that are derived from rainforest plants. For example, rain forests contain the basic ingredients of hormonal contraception methods, cocaine, stimulants, and tranquilizing drugs. Curare (a paralyzing drug) and quinine (a malaria cure) are also found there.
CONSEQUENCES OF DEFORESTATION

Rainforests around the world still continue to fall. Does it really make a difference? Why should anyone care if some plants, animals, mushrooms, and microorganisms perish? Rainforests are often hot and humid, difficult to reach, insect-ridden, and have elusive wildlife.
Actually the concern should not be about losing a few plants and animals; mankind stands to lose much more. By destroying the tropical forests, we risk our own quality of life, gamble with the stability of climate and local weather, threaten the existence of other species, and undermine the valuable services provided by biological diversity. While in most areas environmental degradation has yet to reach a crisis level where entire systems are collapsing, it is important to examine some of the effects of existing environmental impoverishment and to forecast some of the potential repercussions of forest loss. Continuing loss of natural systems could make human activities increasingly vulnerable to ecological surprises in the future. The most immediate impact of deforestation occurs at the local level with the loss of ecological services provided by tropical rainforests and related ecosystems. Such habitats afford humans valuable services such as erosion prevention, flood control, water treatment, fisheries protection, and pollination—functions that are particularly important to the world’s poorest people, who rely on natural resources for their everyday survival. Forest loss also reduces the availability of renewable resources like timber, medicinal plants, nuts and fruit, and game. Over the longer term, deforestation of tropical rainforests can have a broader impact, affecting global climate and biodiversity. These changes are more difficult to observe and forecast from local effects, since they take place over a longer time scale and can be difficult to measure.
Deforestation and the Global Carbon Cycle
Carbon dioxide ( CO2) is the major gas involved in the greenhouse effect, which causes global warming. All the things that produce CO2 (like car burning gas) and the things that consume Co2 (growing plants) are involved in the “global carbon cycle”. Tropical forests hold an immense amount of carbon, which joins with oxygen to form CO2. The plants and soil of tropical forests hold 460-575 billion metric tons of carbon worldwide. Each acre of tropical forest stores about 180 metric tons of carbon.
Deforestation increases the amount of CO2 and other trace gases in the atmosphere. When a forest is cut and replaced by cropland and pastures, the carbon that was stored in the tree trunks (wood is about 50% carbon) joins with oxygen and is released into the atmosphere as Co2.The loss of forests has a great effect on the global carbon cycle. From 1850 to 1990, deforestation worldwide (including that in the United States) released 122 billion metric tons of carbon into the atmosphere, with the current rate being 1.6 billion metric tons per year. In comparison all the fossil fuels (coal, oil and gas) burned during a year release about 6 billion tons per year.Releasing CO2 into the atmosphere increases the greenhouse effect, and may raise global temperature. The role of fossil fuels burned by cars and industry is well known, but tropical deforestation releases about 25% of the amount released by fossil fuel burning. Tropical deforestation, therefore, contributes a significant part of the increasing CO2 in the atmosphere.
Today tropical rainforests are disappearing from the face of the globe. Despite growing international concern, rainforests continue to be destroyed at a pace exceeding 80,000 acres (32,000 hectares) per day. World rainforest cover now stands at around 2.5 million square miles (6 million square kilometers), an area about the size of the contiguous 48 United States or Australia and representing around 5 percent of the world’s land surface. Much of this remaining area has been impacted by human activities and no longer retains its full original biodiversity.
 
The Rainforests of India
The rainforests in India are the centres of species richness and endemism and due to this has the status of being one of the 12 mega-biodiversity countries in the world. Even the two hotspots in India, the Western Ghats and the Eastern Himalayas, owe their status due to the presence of rainforests therein. These forests form very important catchments areas for major river systems, maintain soil and water fertility not only in the immediate vicinity but also hundreds of kilometers away, harbours rich indigenous culture with long traditions of sustainable use of traditional knowledge systems especially on medicines and wild relatives of cultivate crops. It is to these rainforests that more than 80% of the endemic flora and fauna of India are confined. Being the most complex ecosystem, the rain forests are living laboratories in which complex ecological, biological and evolutionary processes that have shaped the Earth.

Bamboo brakes, Muthodi, Karnataka

 
Tropical forest cover in India has been reduced to two major areas: the coastal hills of the Western Ghats (about 55,000 square miles or 135,000 sq. km) and 14,000 square miles (34,500 sq. km) in Northeastern India. Very little of India’s forest cover is considered pristine. 22.8% —or about 67,701,000 hectares—of India is forested. Change in Forest Cover: Between 1990 and 2000, India gained an average of 361,500 hectares of forest per year. The amounts to an average annual reforestation rate of 0.57%. Between 2000 and 2005, the rate of forest change decreased by 92.3% to 0.04% per annum. In total, between 1990 and 2005, India gained 5.9% of its forest cover, or around 3,762,000 hectares. Measuring the total rate of habitat conversion (defined as change in forest area plus change in woodland area minus net plantation expansion) for the 1990-2005 interval, India gained 1.0% of its forest and woodland habitat.Biodiversity and Protected Areas: India has some 2356 known species of amphibians, birds, mammals and reptiles according to figures from the World Conservation Monitoring Centre. Of these, 18.4% are endemic, meaning they exist in no other country, and 10.8% are threatened. India is home to at least 18664 species of vascular plants, of which 26.8% are endemic. 4.9% of India is protected under IUCN categories I-V.

Rainforests of the Western Ghats
The Western Ghats hill range in India contains spectacular landscapes and an incredible array of wild species, many found nowhere else in the world. One among the world’s 34 most biologically diverse “hotspots”, the region has representation of a wide variety of natural ecosystems from grasslands and dry forests to rainforests, rivers, and streams, threatened by a multitude of human activities such as industrialisation, agriculture, grazing, hunting, deforestation, fragmentation, and degradation. Today, rainforests in the Western Ghats occur largely as fragments within a landscape matrix dominated by commercial plantations of tea, coffee, and other cash crops. With an annual deforestation rate of 1.2%, the southern Western Ghats is losing about 500 square kilometres of forest every year. NCF’s programme focuses on human impacts on wild species and habitats, biological surveys, human-wildlife conflict research and mitigation, and restoration to turn the tide of destruction towards conservation.

Forests of the western slopes of the Western Ghats, Konkan

The northern portion of the range is generally drier than the southern portion, and at lower elevations makes up the North Western Ghats moist deciduous forests ecoregion, with mostly deciduous forests made up predominantly of teak. Above 1,000 meters elevation are the cooler and wetter North Western Ghats montane rain forests, whose evergreen forests are characterized by trees of family Lauraceae.The evergreen Wayanad forests of Kerala mark the transition zone between the northern and southern ecoregions of the Western Ghats. The southern ecoregions are generally wetter and more species-rich. At lower elevations are the South Western Ghats moist deciduous forests, with Cullenia the characteristic tree genus, accompanied by teak, dipterocarps, and other trees. The moist forests transition to the drier South Deccan Plateau dry deciduous forests, which lie in its rain shadow to the east.
 

Clear felling, Mahadayi Valley, Karnataka

 
Above 1,000 meters are the South Western Ghats montane rain forests, also cooler and wetter than the surrounding lowland forests, and dominated by evergreen trees, although some montane grasslands and stunted forests can be found at the highest elevations. The South Western Ghats montane rain forests are the most species-rich ecoregion in peninsular India; eighty percent of the flowering plant species of the entire Western Ghats range are found in this ecoregion.

Tropical Montane – Bedthi River Valley, Karnataka

The animal life of the Indian peninsular region is characterised by the absence of many of the Indo-Malay species which are so abundant in the hill forests of the Himalayas. It is the home of the true Indian fauna of which the spotted deer, the nilgai, the blackbuck, the four-horned antelope, and the sloth bear are typical representatives. They are found no where else. Other species like the gaur, the sambar and the muntjac (barking deer) occur both in India and Malay countries. The Western Ghats, in sharp contrast to the adjoining dry zone of the Deccan present a region of great humidity and heavy rainfall. The forests covering the western slopes are at times very dense and composed of lofty trees, festooned with perennial creepers. Bamboos form a luxuriant undergrowth. In parts of the range the forests are more open and the banks of clear streams running through them are covered with spice and betel groves.
The Nilgiris, an offshoot of the Western Ghats, rise precipitously to form extensive grassy downs and tablelands seamed with densely forested gorges or Sholas. They are composed of evergreen trees with dense undergrowth.

1. Malabar Giant Squirrel 2. Lion tailed Macaque

 
Among the species limited to these forests are the Nilgiri langur, the Lion-tailed macaque, the Nilgiri brown mongoose and the striped necked mongoose, the Malabar civet, and the spiny mouse. In the higher levels of the Nilgiris and the Anaimalais are found such characteristically Himalayan animals as the tahr, the pine marten and the European otter.
 

Endemic species of the Western Ghats

One hundred and twenty species of mammals are known from the Western Ghats of which fourteen species are endemic (found only in that area).
 
The mammalian fauna of the Western Ghats is dominated by insectivores (11 species), bats (41 species) and rodents (27 species including porcupine). Few studies have, however, paid attention to the community structure and organisation of these small mammals in the Western Ghats, although there have been attempts to review our understanding of the status and ecology of smaller cats and lesser carnivores.
 
Rainforests of the Northeast India
 
The Northeast India lying between 22-30 degree N latitude and 89-97 degree E longitude, and sprawling over 2,62,379 sq.km., Northeast India represents the transition zone between the Indian, Indo-Malayan and Indo-Chinese biogeographic regions and a meeting place of the Himalayan Mountains and Peninsular India. It was the part of the northward migrating ‘Deccan Peninsula’ that first touched the Asian landmass after the break up of Gondwanaland in the early Tertiary Period. Northeast India is thus the geographical ‘gateway’ for much of India’s flora and fauna, and as a consequence, the region is one of the richest in biological values. It is in this lowland-highland transition zone that the highest diversity of biomes or ecological communities can be found, and species diversities within these communities are also extremely high.
 
Northeast India is blessed with a wide range of physiography and ecoclimatic conditions. The State of Assam has extensive flood plains, while Khangchendzonga in Sikkim stands 8586 m. tall. Cherrapunjee in the State of Meghalaya holds the record for the highest rainfall in a single month (9,300 mm) as well as the most in a year (26,461 mm) in India, while the nearby Mawsynram has the world’s highest average rainfall (11,873 mm). The forests in the region are extremely diverse in structure and composition and combine tropical and temperate forest types, alpine meadows and cold deserts. There are regions, for example, in the State of Sikkim, where the faunal assemblages also change rapidly from tropical to subtropical, temperate, alpine and finally to cold desert forms.
 
After the Andaman and Nicobar Islands and the Western Ghats, Northeast India forms the main region of tropical forests in India, especially the species-rich tropical rain forests. The tropical semi-evergreen and moist deciduous forests in the lowlands of this region extend south and west into the subcontinent, and east into Southern China and Southeast Asia. The subtropical forests of the region follow the foothills of the Himalaya to the west; also extend into Southeast China in the east. Himalayan temperate and subalpine zone forests extend from northern Pakistan and adjacent Afghanistan through Northeast India to Southwest China. Each of the eight States of the region, namely Arunachal Pradesh, Assam, Meghalaya, Manipur, Mizoram, Nagaland, Sikkim and Tripura, boast of several endemics in flora as well as fauna. This region represents an important part of the Indo-Myanmar biodiversity hotspot.
 
1. Dooars forests, North Bengal 2. Golden Langur
 
The primary vegetation in extensive areas of the Northeast India has been disturbed and modified and in some places destroyed by seismic activities, frequent landslides and resultant soil erosion. While these natural causes have contributed only marginally to the change in vegetation type, it is the activity of Man that has led to the irreversible transformation in the landscapes and has resulted in colossal loss of biodiversity in the entire region. Human influences have pushed many species to the brink of extinction and have caused havoc to natural fragile ecosystems. Such devastations to natural ecosystems are witnessed almost everywhere in the region and is a cause of great concern.

 
1. Slow Loris 2. Reticulated Python

Northeast India has 64% of the total geographical area under forest cover and it is often quoted that it continues to be a forest surplus region. However, the forest cover is rapidly disappearing from the entire region. There has been a decrease of about 1800 sq.km. in the forest cover between 1991 and 1999. More worrisome still is the fact that the quality of the forest is also deteriorating, with the dense forests (canopy closure of 40% or more) becoming degraded into open forest or scrub. Though there is a succession of several edaphic formations, a vast area of land has already been transformed into barren and unproductive wastelands. This being the case, the statistics of ‘more than 64 % of the total geographic area in this region under forest cover’ could be misleading. For example, though the forest cover in Manipur extends to 78% of the total geographic area, only 22% of forest area is under dense forest cover and the rest has been converted to open forests.
 
 
Except in the Brahmaputra and Barak valleys of Assam where substantial areas are under agriculture, little of the land is available for settled cultivation. Hence, shifting agriculture or slash-and-burn agriculture is the major land use in Northeast India and extends over 1.73 million ha. Different agencies have come up with different figures concerning the total area under shifting cultivation (jhum) in the region. What is not disputable is that with an ever shortening jhum cycle, the other human influences have caused environmental degradation with disastrous consequences.The forests of Assam once acted as a sponge, absorbing the tremendous impact of the monsoons. The natural drainage of the vast northeastern Himalaya is channelled through Assam and with the loss of thick forest cover, Brahmaputra, one of the largest and fastest flowing rivers of the subcontinent is creating havoc in the State. Floods that have devastating effects are now common to Northeast India and protecting the forests is a difficult problem.
 
 
The Rainforests of the Andamans & Nicobar Islands

 
The Andamans and Nicobar Islands have tropical evergreen rain forests and tropical semi-evergreen rainforests as well as tropical monsoon moist monsoon forests.
 
There are 572 islands in the territory, of which only approximately 38 are permanently inhabited. Most of the islands (about 550) are in the Andamans group, 26 of which are inhabited. The smaller Nicobars comprise some 22 main islands (10 inhabited). The Andamans and Nicobars are separated by a channel (the Ten Degree Channel) some 150 km wide.The total area of the Andaman Islands is some 6,408 km²; that of the Nicobar Islands approximately 1,841 km².

 
Aerial view -Andamans & Nicobar Islands

Andaman & Nicobar Islands are blessed with a unique tropical rainforest canopy, made of a mixed flora with elements from Indian, Myanmarese, Malaysian and endemic floral strains. So far, about 2,200 varieties of plants have been recorded, out of which 200 are endemic and 1,300 do not occur in mainland India.The South Andaman forests have a profuse growth of epiphytic vegetation, mostly ferns and orchids. The Middle Andamans harbours mostly moist deciduous forests. North Andamans is characterised by the wet evergreen type, with plenty of woody climbers. The north Nicobar Islands (including Car Nicobar and Battimalv) are marked by the complete absence of evergreen forests, while such forests form the dominant vegetation in the central and southern islands of the Nicobar group. Grasslands occur only in the Nicobars, and while deciduous forests are common in the Andamans, they are almost absent in the Nicobars. The present forest coverage is claimed to be 86.2% of the total land area.

 
 
 
References: Wikipedia, Mongabay,com, Animal corner.com, The Western Ghats by Mohan Pai, Nature Conservation Foundation, Biodiversity of Northeast India an Overview -V.Ramakantha, A.K.Gupta, Ajith Kumar
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Vanishing Species – The Great Indian One-horned Rhinoceros

An article by Mohan Pai

 

The Great Indian One-horned Rhinoceros
(Rhinoceros unicornis)

A kilogram of Rhino horn was priced at $ 60,000 in the International market in 1994.

No wonder the species is facing extinction.

Rampant killing for superstitious & religious beliefs has driven this largest of all Asian rhinoceros to near extinction. The two-horned rhino (Didermocerus sumatrenis) became extinct in the hill tracts of Assam by the end of the nineteenth century.

When Mary Victoria Leiter Curzon, the wife of the Viceroy of India, Lord Curzon, visited Kaziranga in 1904 and having failed to see even a single rhinoceros, for which the area was renowned, she persuaded her husband to take urgent measures to protect the dwindling species which he did by initiating planning for a their protection. On 1 June 1905, the Kaziranga Proposed Reserve Forest was created with an area of 232 km2 (90 sq mi).Formerly extensively distributed in the Gangetic plain to day it is restricted to parts of Nepal (Chitwan), North West Bengal (Dooars) and Kaziranga in Assam. The world’s largest population of this animal is in Kaziranga National Park followed by Jaldapara Wildlife Sanctuary and a small population in Gorumara National Park in North Bengal. A few have been relocated in Dudhwa NP.

Lady Curzon

Many legends and beliefs are attached to the rhinoceros.
“In Europe, during the Middle Ages, its horn was generally believed to have peculiar medicinal virtues.
In Nepal the flesh and blood of the rhinoceros is considered highly acceptable to the manes. High caste Hindus and most Gurkhas offer libation of the animal’s blood after entering its disembowelled body. On ordinary Sraddha days the libation of water and milk is poured from a cup carved from its horn. The urine is considered antiseptic and is hung in a vessel at the principal door as a charm against ghosts, evil spirits, and diseases. These beliefs connected with the rhinoceros are prevalent in varying forms in Burma, Siam, and China. They set a great value upon the animal and provide the main reason for its persecution.” (S. H. Prater)

In the nineteenth and end early twentieth century, the Indian Rhinoceros was hunted relentlessly. Reports from the middle of the nineteenth century claim that some military officers in Assam individually shot more than 200 rhinos. In the early 1900s, colonial officials became concerned at the rhino’s plummeting numbers. By 1908 in Kaziranga, one of the rhino’s main ranges, the population had fallen to around 12 individuals. In 1910, all rhino hunting in India became prohibited.

Human interference is one of the major factors responsible for putting the life of One Horned Rhinos at risk. Grazing of livestocks inside the protected areas makes the animals vulnerable to several fatal diseases. Unabated poaching activities mainly for it’s horn is pushing this animal to the brink of extinction. The horn is used as a medicine and an aphrodisiac. Medicinal purposes are as a pain reliever and a fever suppressant. For centuries, Asians have believed that powdered rhino horn could cure everything from fevers and nose bleeds to measles, diphtheria, and food poisoning. Many also believe powdered rhino horn helps retain the vigor of youth and contributes to sexual stamina. However, there are no scientific studies that show that rhino horn is affective for any of these purposes. In addition to the horn, rhino hide; blood, urine, and dung also have economic value.Recent media reports from Kaziranga National Park on Great One Horned Rhino poaching are shocking and have put the government on tenterhooks. Given the present set of infrastructure that is available with the officials who stay on guard, they simply stand no match with sophisticated weapons the poachers carry. A drastic remedial step against the menace of poaching is something that has to be sorted out today or tomorrow may just be too late.

Taxonomy, Ecology and Behavior

In size it is equal to that of the white rhino in Africa. Not including the white rhino, it is the largest of all rhinos. Fully grown males are larger than females in the wild, weighing from 2200- 3000 kg (4,800 – 6,600 lb). Female Indian rhinos weigh about 1600 kg. The Indian Rhino is from 1.7 to 2 m tall (5.7 to 6.7 feet) and can be up to 4m (13 ft) long. The record-sized specimen of this rhino was approximately 3500 kg.The Great One-Horned Rhinoceros has a single horn; this is present in both males and females, but not on newborn young. The horn, like human fingernails, is pure keratin and starts to show after about 6 years. In most adults the horn reaches a length of about 25 centimeters, but have been recorded up to 57.2 centimeters in length. The nasal horn curves backwards from the nose. Its horn is naturally black. In captive animals, the horn is frequently worn down to a thick knob.

The great Indian rhinoceros is active throughout the day, although the middle of the day is spent wallowing and resting in the shade. Wallowing takes place in lakes, rivers, ponds, and puddles, and is especially frequent in the hot seasons to cool off. This activity is believed to be important with thermo-regulation and the control of flies. Drinking occurs almost every day, and mineral licks are visited regularly. Population densities vary from 0.4-4.85 animals per square kilometer depending on the habitat. Only the strongest males breed, and they have home ranges between 2-8 square kilometers in size. These home ranges are not true territories, and overlap each other. When disturbed, these rhinos generally flee, though they have been reported attacking, which they do with their head down. Smell is important in communication, with urine, feces, and glandular secretions carrying the messages. Rhinos have very poor eyesight, but their senses of smell and hearing are well developed.

A 1515 woodcut of One-horned rhinoceros by the famous German painter Albrecht Durer

Distribution

The greater one-horned rhinoceros is commonly found only in South Asia and South East Asia. Historically, the rhinos were distributed in the floodplain and forest tracts in Brahmaputra, Ganges and Indus river valley. Today, however, no more than 2,000 remain in the wild, with only two populations containing more than 100 rhinos: Kaziranga National Park in Assam, India (1,200) and Royal Chitwan National Park (CNP), Nepal (600).

Habitat & Feeding

Alluvial plain is the primary and preferred habitat. Adjacent swamp and forest areas are also used. Rhinoceros are herbivorous in nature. They feed on grass, fruit, leaves, branches, aquatic plants, and cultivated crops. Tall reedy grasses are preferred to short species. When eating aquatic plants, Rhinoceros submerge their entire heads and tear the plant up by the roots. Foraging occurs at night, in early morning, or late afternoon to avoid the heat of the day. Rhinoceros drinks daily and is fond of mineral licks.
Reproduction

Breeding occurs throughout the year. Only dominant bulls mate, and it is believed that they can assess the reproductive status of females through scent. Courtship may seem aggressive. Males chase females and sometimes fighting often ensues. After a gestation period of 480 days, one young is born weighing 70 kg. Weaning usually occurs in one year, although it may last up to 18 months. Females have young at intervals of about three years. One week before the next birth, the female will chase away her previous calf. Sexual maturity is reached at an age of 9 years for males, and 4 for females. The life-span is about 40 years.

Conservation Status and Threats

The great Indian rhinoceros is listed as endangered by the International Union for Conservation of Nature and Natural Resources (IUCN) (1996). The main source of danger for this (and all) rhinos is the Oriental belief that its horn, among other parts, has medicinal or magical properties. The Indian rhinoceros was already considered a ‘vanishing race’ by the beginning of the 20th century, primarily due to the conversion of alluvial plain grassland to cultivated fields. Hunting, was also a factor in the decimation of the population. Despite protection measures, poaching remains a serious threat today due to the demand for rhino horn in Oriental medicine; in 1994 for example, a kilogram of rhino horn was worth approximately US $ 60,000.

Pic by Siva A. N.

 
References: The Book of Indian Animals by S. H. Prater, Wikipedia, Arunachal Front – 24/2/2008
 
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North Bengal, India – Biodiversity

An article by Mohan Pai

Biodiversity
North Bengal
North Bengal comprising the districts of Jalpaiguri, Darjeeling, Dinajpur and Cooch Behar lies at the foothill of the great Himalayas. The area covers the moist and dense riverine forests of the Bengal Dooars (Duars) and the stark foothills of the snow-capped Kanchenjunga range. The unique climatic and ecological conditions makes North Bengal an unique home for a large variety of mega-fauna & superb restricted bird species. Bhutan and Nepal are two beautiful countries having an easy access from North Bengal. Sikkim previously an independent country joined union of India later on as one of its states. All these three beautiful places are all adjacent to parts of North Bengal.

 

North Bengal is a term, for the parts of Bangladesh and West Bengal. The Bangladesh part denotes the Rajshahi Division. Generally it is the area lying west of Jamuna River and north of Padma River, and includes the Barind Tract. The West Bengal part denotes Cooch Behar, Darjeeling, Jalpaiguri, North Dinajpur, South Dinajpur and Malda districts together. It also includes parts of Darjeeling Hills. Traditionally, the Hooghly River divides West Bengal into South and North Bengal, divided again into Terai and Dooars regions.

Red Panda

This region comprising the state of Sikkim and the adjoining parts of North Bengal – Darjeeling and Kalimpong, is a rugged strip of vertical mountain country. Wedged between Nepal, Tibet, Bhutan, and the North Bengal Plains of India. This tiny region is just 90 km wide and 150 km deep. The grain of the country rises from near sea level to 8500 meters, in a short distance, The great Himalayan Range with its giant spurs – Singelila and Chola, virtually enclose this region in a titanic horseshoe. Starting from the plains of North Bengal tangled interlacing ridges rise range after range to the foot of the great wall of high peaks and passes opening into Tibet, Nepal and BhutanThe climate varies between the tropical heat of the valleys and the alpine cold of the snowy regions. With rainfall averaging 348 cm, it is the most humid region of the Himalayas. Dry season is from November to April. The altitudanal zones of vegetation range from tropical, sub tropical, temperate to Alpine – some places only 10 km in a direct line separates the palm growing valleys from perpetual snow. The varied terrain – from the pleasant humid foothill valleys below 1000 meters, to the arctic cold of the snow capped peaks up to 8000 meters, has created marked altitudinal zonation in the humidity, rainfall, climate and vegetation. 

One-horned rhinoceros


THE TERAI

The Terai (“moist land”) is a belt of marshy grasslands, savannas, and forests at the base of the Himalaya range in India, Nepal, and Bhutan, from the Yamuna River in the west to the Brahmaputra River in the east. Above the Terai belt lies the Bhabhar, a forested belt of rock, gravel, and soil eroded from the Himalayas, where the water table lies from 5 to 37 meters deep. The Terai zone lies below the Bhabhar, and is composed of alternate layers of clay and sand, with a high water table that creates many springs and wetlands. The Terai zone is inundated yearly by the monsoon-swollen rivers of the Himalaya. Below the Terai lies the great alluvial plain of the Yamuna, Ganges, Brahmaputra, and their tributaries.

DOOARS

The Dooars or Duars are flood plains at the foothills of the eastern Himalayas in North-East India around Bhutan. Duar means door in both Assamese and Bengali languages and forthe Bhutanese people can communicate with the people living in the plains. This region is divided by the Sankosh river into the eastern and the western Duars consisting of an area of 8,800 square kilometer (3,400 square-mile). This region was controlled by the Kingdom of Bhutan when the British annexed it in 1865 after Bhutan War. They are now part of the Indian states of Assam and West Bengal.Many wars have been fought over them. These plains are very fertile. There are innumerable streams and rivers flowing through these fertile plains from the mountains of Bhutan. In Assam the major rivers are Brahmaputra and Manas, and in northern West Bengal the major river is the Teesta besides many others like the Jaldhaka, Torsha, Sankosh, Dyna, Karatoya, Raidak, Kaljani among others.The forested areas of Northern West Bengal present a plethora of Wildlife.This mixed dry deciduous forest land dotted with grasslands, harbors the largest diversity of mega fauna in West Bengal. A large range of foothill forest in North Bengal is called Dooars. Once the whole area was under the reign of Koch Raj. Tea Gardens, alpine landscape, transparent river, National Parks and the Wildlife Sanctuary creates a paradise. Beautiful motorable roads cut through deep forests, rich with wildlife. Mauve hills stand at the end of velvet green plains. The forests echo with the melody of birds. In between, there are fabulous wildlife sanctuaries with, log cabin lodges and valleys carpeted with tea gardens. Dooars is the habitat of the rare Toto tribes.

The most convenient entry point to Dooars is through Siliguri by road. Regular bus connections between Siliguri and most important spots in the Dooars. Also broad gauge rail connection between New Jalpaiguri and Mal, Madarihat, Nilpara, Jainti, Mainaguri, Dhupguri and Falakata. Metre gauge rail connection between Siliguri and most spots.

Dooars Jungle in North Bengal are:- Buxa, Gorumara, Jaldapara, Neora Valley, Bindu, Jaldhaka, Jhalong, Malbazar, Samsing

The state has 4031 sq. Km. of forests, under protected area network which is 34% of the State’s total forest area and 4.54% of the total geographical area. There are five National Parks, fifteen sanctuaries, two tiger reserves and one biosphere reserve. The PA network includes 1055 sq. km. of sanctuaries, 1693 sq. km. of National Parks, the balance are being represented by buffer areas of the two tiger reserves, viz. Sunderbans Tiger Reserve and Buxa Tiger Reserve.

Habitat Loss

Habitat loss has largely taken place due to human intervention and change in land use pattern. Large scale conversion of natural habitats for a variety of purposes have led to shifts in floristic pattern (like in case of weed flora) and also fragmentation and loss of natural corridors for animals, leading to man-animal conflict. After the armed conflict with China in 1962, for example, the Army has been permanently stationed in Binnaguri, which has led to loss of the elephant corridor. Similar is the case of tea gardens in North Bengal, which have also witnessed man-animal conflict after forests were clearfelled. Habitat loss has led to decline in several species, and fauna like otter, Bengal jackal, pangolin, mongoose, porcupine are among those which are not frequently sighted today. Much needs to be studied about the underlying inter-relationships between biodiversity and the anthropogenic element, to clearly establish how harm to flora and fauna as a result of human interference must be stemmed.

Tea Gardens
The jungles of North Bengal is an extremely rich biodiversity zone but today faces, a declining rhino population, political unrest in the entire zone and incidences of elephants being hit by speeding trains in their migratory corridors are some of the glaring issues. In the face of industrial resurgence, land acquisition has become a grave issue, The locals are least concerned about preserving the forest ecosystem. Efforts are on to set up a tourism development centre in the area that will hamper the forest biodiversity. Industrialisation has a considerable impact on environment. Another disturbing environmental site is the East Calcutta Wetlands that has been declared a Ramsar Heritage Site but is poorly maintained. In the tea gardens of the Dooars, huge amounts of pesticides are used that have a damaging effect on the floral biodiversity. All’s not well in the jungles of North Bengal with recent incidences of loss of an increasing number of wild fauna and the major factors contributing to the depleting wildlife habitat are lack of proper administration by forest officials and hazardous methods of conservation. The North Bengal forests are reeling under severe crisis owing to the threat from the fringe populace residing in and around the plains of the Dooars. The tension brewing in the tea sector has caused misery for a huge section of locals and this is creating increased pressure on the forest resources. There are other prevailing threats that are posing a danger over a considerable period of time, including excessive grazing that has not been taken care of. The rising conflict between man and animals has placed certain prominent categories of mammalian species in jeopardy. The rapid tourist influx has also degraded the environmental scene in North Bengal since it generates a lot of non-biodegradable wastes in the hilly areas. Efficient treatment and recycling of waste will provide a source of livelihood for locals, make the environment safe and clean and will be a draw for travellers.
Dooars forest

The Forests & Protected Areas

 

The forests of West Bengal are classified into seven categories viz., Tropical Semi-Evergreen Forest, Tropical Moist Deciduous Forest, Tropical Dry Deciduous Forest, Littoral and Swampy Forest, Sub-Tropical Hill Forest, Eastern Himalayan Wet Temperate Forest and Alpine Forest. The state has a recorded forest land of 11,879 sq. km., of which 7,054 sq. km. is Reserved Forest, 3,772 sq. km. is Protected Forest and 1,053 sq. Km is Unclassifieded State Forest, thus constituting 13.38% of the geographical area of the state. Under the conservation and protection regime the State has one Biosphere Reserve, two Tiger Reserves, five National Parks and 15 Wildlife Sanctuaries. Four out of five National Parks are located in the North Bengal along with one tiger reserve and seven Wildlife Sanctuaries.


Elephant Country

Neora Valley National Park

The Neora Valley National Park, spread over an area of 88sq.km. in the Darjeeling district of West Bengal was established in April 1986. The park, a unique area of rich bio-diversity lies in the Himalayan foothills and is bordered on the east by Western Bhutan and the forests of Neora Valley, one of the least tracts of virgin wilderness in the country sustains a unique eco-system where tropical, sub-tropical, sub-temperate, and temperate vegetative system still harbours a wealth of flora and fauna.
Buxa National Park
The Buxa Tiger Reserve with an area of 759 sq. km was established in the year of 1982-83 at the north eastern corner of West Bengal bordering Bhutan and Assam. The core area of 315sq.kms around the Buxa Duar Fort was declared a National Park in January 1992. This park is located in eastern Dooars (rolling humid plains) at 2600 ft above sea level. The Dooars comprises of deciduous forests which are densely wooded and grasslands and is home to some of West Bengal’s most varied flora and fauna.
Singalila National Park
The vegetation of these virgin forests mainly alpine, changes with the range in altitude. The main tree species found are the Rhododendron, Magnolia, Oak, Hemlock, Silver Fir, Juniper, Mailing Bamboo, Buk, Kawla, Bhujpatra etc. Other flora includes primulas, aconitums, gentians, arisaemas and orchids adorning the forest clearings. The fauna found in the park are leopard, serow, pangolin, elephant, chinkara, red panda, barking deer etc. The park has a variety of birds such as pigeons, doves, sibia, minivet, magpie, cuckoo, hornbills, Kaleej pheasants and a large number of migratory birds.
Gorumara National Park
Gorumara National Park is located in the Dooars (rolling hill slopes) region of Jalpaiguri district in West Bengal. This small forest area famous for its natural population of the Great Indian one horned Rhinoceros was declared a wildlife sanctuary in the year 1949.
Later in the year 1992, it was established as a National Park, comprising 80 km of diverse forests.
Jaldapara Wild Life Sanctuary
The sanctuary lies amidst the idyllic surrounding created by the mysterious backdrop of the Mountains of Bhutan and the confluence of river Torsa and Malangi. The sanctuary covers an area of 100sq.km. The park is the home of several wild lives, which includes the famous one horned Indian Rhinos, Swamp Deer, wild boar, leopard and tigers. The sanctuary has the maximum number of one-horned rhino in India after Kaziranga. The park has excellent facilities for wild life enthusiasts.

 

Crested Serpent Eagle

BIRD HAVEN
The varied terrain – from the pleasant humid foothill valleys below 1000 meters, to the arctic cold of the snow capped peaks up to 8000 meters, has created marked altitudinal zonation in the humidity, rainfall, climate and vegetation. This factor is responsible for the great variety and abundance of the resident bird life, making this area arguably one of the richest areas of its size anywhere in the world. 527 species of resident birds have been recorded. In addition there are vagrants, and transients on migration. It is estimated that more than 30 percent of the species of the Indian Sub continent can be spotted in this region.
Lava
Lava and Neora Valley National Park are the prime birding destinations in North Bengal. Located 35 Kms from Kalimpong, it is surrounded by very large tracts of protected forests ranging in elevation between 1600 and 2400 m. There are several sites for bird watching and photography around Lava and the adjoining Neora National Park. Some of the rarities that can be found at Lava are : Satyr Tragopan, Rufous-throated and Spotted Wren Babblers, Yellow- throated Fulvetta, Ashy wood Pigeon, Red – Faced Liocichla, Blue-fronted Robin, Long-billed thrush, Cutia, Rusty-belied shortwinged, various Laughing Thrushes ,Warblers and Sunbirds. 

Mallard

Death on the Tracks

There have been repeated incidents of elephant and bison deaths on railway tracks running through the forests of North Bengal. In the last seven years, 26 elephants have been killed in North Bengal. Nine elephants have been killed in the last two years alone. Most of the cases have been reported from a 100-km stretch between Alipurduar to Siliguri. The track was converted to broad gauge line in 2004 allowing an increase in train speed. 

Elephant knocked down by speeding train
This stretch passes through prime protected areas like Buxa Tiger Reserve, Jaldapara Wildlife Sanctuary, Mahananda and Chapramari Wildlife Sanctuaries. There are four extremely vulnerable corridors in this stretch that are fragmented by several railway lines.Ten cases of elephant deaths have been reported from Panjhora region under Chapramari Wildlife Sanctuary, five cases from Gulma under Mahananda Wildlife Sanctuary, four cases from the Mongpong stretch under the Kalimpong division and three in the Rajabhatkhawa stretch under Buxa Tiger Reserves.What is more alarming is that there has been a sudden rise in the number of goods train in this stretch in the last two years. While restrictions on the speed limit of the train passing through the area have been imposed, the wild animals continue to be killed on these tracks. Nearly 43 km of railway tracks cut across different wildlife sanctuaries in North Bengal.
Rampant Poaching
Poaching of wild animals including leopards and tigers continues with impunity. Three leopards and a tiger were killed recently. A poacher was recently arrested with 4 leopard skins, 10 kilos of tiger bones and 16 kg. of rhino skins. International Wildlife trade is involved in poaching operations.

Leopard & Rhino skins

Major threat to forests also comes from organized gangsterism in the field of timber smuggling and poaching.

Acknowledgements: Wikipedia, West Bengal Forest Department, Dept. Of Environment, Government of West Bengal, The Telegraph, Himalayaandnorthbengal.com


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