SCIENTISTS believe that the Western Ghats came into existence during the Jurassic and millions of years before the Himalayas began to rise. The Western Ghats are thus one of the world’s oldest mountain ranges, rich in biodiversity and renowned for their endemic species; 30 to 40 per cent of the various classes of plants and animals known to science may be unique to the mountain chain. The rich biodiversity, the high levels of endemism and the imminent threats to the long-term survival of many species and their habitats have placed the Western Ghats among the world’s biodiversity “hotspots”.
The Western Ghats span nearly 1,600 kilometres between the Tapti river in the north and Kanyakumari in the south. They form more or less a continuous chain but for the Palghat Gap. Topographically, they vary from sea level, as they touch the Arabian Sea in the west, to peaks that exceed 2,600 metres in elevation. The topographic diversity has created several landscape-specific climatic zones within the mountain range. Winter temperatures drop to sub-zero levels locally in the Nilgiris and other high peaks. Rainfall also varies considerably—the lowest could be around 600 millimetres annually and the highest exceeds 7,000 mm. A combination of prehistory, landscape heterogeneity and human-induced changes has rendered the Western Ghats a real wonderland, a mountain range of endless natural enchantment.
The enchanting wilderness of the Western Ghats is best relished on foot as some of its most picturesque areas are not accessible by vehicles. The rugged terrain and tropical climate make trekking through the Western Ghats a delightful challenge. In fact, this is precisely what the book under review, Walking the Western Ghats , is all about: a lively narration by A.J.T. Johnsingh of his adventures on foot across the many landscapes of the Western Ghats. The book has 22 chapters. Each chapter is devoted to a specific landscape and illustrated with excellent photographs and maps. The author has thoughtfully arranged the chapters so that they take the reader across the Western Ghats from the south to the north. Although the Western Ghats extend into Gujarat, the book does not devote a chapter to this State.
By convention, the word wildlife is synonymous with vertebrate animals with a general overemphasis on mammals. As a result, mammals are most commonly treated as flagships in worldwide conservation programmes. Keeping with the worldwide trend, the author has primarily focussed on mammals while narrating his experiences in the different landscapes of the Western Ghats. He has in fact used mammals as the yardsticks to measure the health of specific landscapes.
There are around 1,200 species of vertebrate animals in the Western Ghats, a little over 10 per cent of which are mammals. Although the diversity of mammals in the Western Ghats is relatively low, the fauna includes charismatic species such as the tiger. Another mammal speciesthat has attracted a lot of attention from conservationists is the endemic Nilgiri tahr. It is unique in being the only species of mountain goat that is found in a tropical region. Biologists suggest that it migrated south into the Western Ghats more than a million years ago during the ice ages when even southern India experienced a temperate climate. And as the climate grew warmer, the tahr moved upwards into the hills of the Western Ghats where at present it is confined to a few landscapes between the Nilgiris and Kanyakumari with a total population size of less than 3,000 individuals.
The Nilgiri tahr is one of the prey animals of the tiger in the higher elevations as is the blackbuck in the drier eastern foothills of the Western Ghats. While the tiger preys on a range of hoofed animals known as ungulates, its preferred prey is the sambar, a large deer found widely in India. According to Johnsingh, the abundance of sambar is key to the survival of the tiger in the Western Ghats. The tiger also preys on the gaur, a species of wild cattle and the largest bovine species. Herds of gaur in the Western Ghats are a sight to behold.
Recent surveys suggest that there are around 700 tigers in the Western Ghats. Tigers are found southwards from Maharashtra to Kanyakumari. However, the largest population in the Western Ghats is found in the Nilgiri landscape within the protected areas of Bandipur, Nagarhole, Mudumalai and Wayanad. Other large predators are the leopard and the dhole, a species of wild dog. Although there is little knowledge of the size of the leopard population in the Western Ghats, what is known is that it is more adaptive than the tiger and can survive in a wider range of habitats, including those heavily impacted by humans. It is this character that brings the leopard into greater conflict with humans than the tiger. The dhole is a social animal, hunting in packs much as the wolf does. The author began his career as a wildlife biologist studying the dhole in the Western Ghats. It is obviously one of his favourite mammals; the book talks about it frequently.
The Western Ghats are important for their large population of elephants. Estimates may vary, but it is generally agreed that there are more than 8,000 elephants spread across the different landscapes. It is also said that this is the single largest population of the Asian elephant anywhere throughout its range. Elephants move in herds and have a large home range as the herds move across and between landscapes. As a result, elephant corridors have been identified and established throughout the Western Ghats to improve connectivity between the landscapes. The elephant is considered an “umbrella species” because it plays a major role in the functioning of the ecosystem and provides opportunities for many species of plants and animals to survive in the landscape. Other mammals that thrive under the umbrella of the elephant are the spotted deer (or chital), the sloth bear and several species of primates.
All the primate species in the Western Ghats are primarily arboreal. Of these, the three endemic species, namely, the Nilgiri langur, the black-footed grey langur and the lion-tailed macaque, have attracted the attention of conservationists from time to time. The lion-tailed macaque emerged as the flagship of the Silent Valley. Protecting the Silent Valley from being submerged under a major hydroelectric project is still India’s most successful outcome of environmental activism.
Silent Valley The Silent Valley is today a national park and part of the Nilgiri Biosphere Reserve recognised by the United Nations Educational, Scientific and Cultural Organisation (UNESCO). Walking through the Silent Valley can be one of the most memorable experiences for any nature lover. It is home to a number of endemic species of plants and animals, including birds. It is an important sanctuary for birds in the Western Ghats. Around 550 species of birds are found in the Western Ghats, 27 of which may be endemic. Although endemism in birds is the lowest among all classes of animals known to science, there are some unique species in the Western Ghats. Laughing thrushes are melodious birds. Current taxonomy recognises three species in the Western Ghats and one in Sri Lanka. The three Western Ghats’ species are endemic. The greatest diversity of laughing thrushes in the Indian subcontinent is, however, in the Himalayas where there are around 30 known species.
While the laughing thrush is a good example of a Himalayan bird isolated in the Western Ghats, there is another example, the great pied hornbill. This is the largest bird in the Western Ghats and, subject to available habitat, can be abundant locally. Its population in the Western Ghats has been isolated from that of the Himalayas for many years now.
Apart from birds, wildlife species that find frequent mention in the book are the crocodile, the king cobra and the large river fish the masheer. The masheer is the largest fish species in the Western Ghats. It is highly localised and confined to specific landscapes. It is of such interest to both the local fisherman and the adventure-seeking angler that in the Moyar river a short stretch is named after it!
Unique problems The author ends each chapter highlighting specific conservation issues. Each landscape has its unique problems. However, the most general problems in the Western Ghats are poaching; loss of habitat due to human encroachment; tourism and pilgrimage; invasive alien species of plants; and the competition to wildlife from domestic and feral animals. As the Western Ghats run across six States, the response to these conservation challenges are varied. As a result, a species of animal that enjoys a fair amount of protection in one State may get poached if it crosses the border into a neighbouring State. The absence of a unified approach to conservation of biodiversity in general and wildlife in particular across States is a major cause of concern.
Landscape-specific problems include mining. This is particularly a problem in the central and northern Western Ghats (also called the Sahyadris). The author vividly describes the environmental problems caused by iron ore mining in the Kudremukh National Park. Tourism and pilgrimage and the associated burden of human waste management are major challenges. Attention has specifically been drawn to the case of the Sabarimala temple within the Periyar Tiger Reserve. Plastics and other solid wastes strewn all over not only mar scenic landscapes but can pose a danger to wildlife. Roads and unplanned tourist resorts interfere with the free movement of large mammals such as the elephant and the tiger, leading to conflicts.
Since Europeans colonised parts of the Western Ghats, several species of alien plants have been introduced. Some of them have become invasive, destroying natural grasslands. Plants such as the lantana have reduced the scope of forest regeneration and during summer become fuel that trigger extensive forest fires. Others, including the wattle, have created extensive “unpalatable greenery”, depriving herbivores of their natural forage locally.
Rivers and streams are threatened by pollution, overfishing and damming. Fish species that have been introduced in the ghats have proliferated in the reservoirs, posing a threat to endemic species. The masheer, the flagship species of certain rivers such as the Kabini and the Parambikulam, is locally decimated because of overfishing and pollution.
Despite Johnsingh’s efforts to make the reading enjoyable, the chapters end on a damp note. This is not his fault but reality has prevailed. The magnificent Western Ghats and its biodiversity are dying a slow death. While this is not evident to a vehicle-bound tourist, it makes a serious conservationist lament.
An integrated conservation plan for the entire Western Ghats has to be drawn up and implemented. All the States the Western Ghats run through must work together. This is the refrain in the book. The book will be of great value to all those interested in conserving the Western Ghats and their rich natural heritage. It is a necessary guide to State Forest Departments and conservation planners.
Ranjit Daniels is a managing trustee of Care Earth, a Chennai-based biodiversity research organisation. He has travelled and worked in the Western Ghats for more than 30 years. His field of research specialisation is the ecology of vertebrates in tropical ecosystems.