Amphibians are considered to be the best indicators of environmental health. A decline in amphibian populations indicates ecosystem deterioration that might affect a wider spectrum of the earth’s biological diversity. During the last 12 years there has been a great concern, worldwide, about the rapid decline in amphibian populations. Many reasons have been attributed to the loss of amphibians including habitat loss UV-B radiation, global warming, toxic chemicals, pathogens that destroy eggs and larval stages, direct harvest and others. Of these, loss of habitat seems to be the most significant factor, at least in tropical countries.
In this book, 72 species of Indian amphibians including caeilians have been described. These amphibians are common and widely distributed in peninsular India and represent about one third of all amphibian species known in India. The descriptions are simple and contain, although limited, details of other closely-related species, taking the actual number of amphibian species discussed to well over 100.
The many illustrations provided throughout the species accounts and the illustrated keys should make it possible for students and amateur naturalists to identify amphibians in the field without much difficulty. To avoid any confusion that might arise from scientific names that keep changing, those names that have been the most consistently used in India have been retained in this book. However, all recent changes have been included as synonyms. Additionally, an appendix that lists out all the known species of Indian amphibians (at the time that the book was written) has been provided.
R J Ranjit Daniels was born on June 5,1959 in Nagercoil-a small hill town in the southern Western Ghats. Encouraged by his parents, he pursued his interest in nature watching and drawing animals, especially birds. The many pets that he raised during his early years, that included amongst others frogs, were his greatest source of inspiration and learning. The graduation from hobby to profession took place many years later in 1989 after a short visit to Panama.
After being awarded a doctoral degree in 1990 by the Indian Institute of Science for his study of birds of the Western Ghats, Ranjit Daniels pursued his post-doctoral research on amphibians. He moved to Chennai in 1992 and over the past decade has travelled in the Western Ghats, Eastern Ghats and the Great Nicobar Island studying amphibians and other lower vertebrates (fish and reptiles).
In chennai, he has served as the Research Scientist the Madras Crocodile Bank, as Honorary Secretary at the Chennai Snake Park and also as principal Scientific Officer (Biodiversity and Biotechnology) and Chair (Biodiversity) at the M S Swaminathan Research Foundation. He founded Care Earth in June 2000 and has since been serving as the Director of this young organization that is dedicated to biodiversity research and training.
India has a fascinating flora and fauna. Not only are the large and spectacular animals like tigers and elephants fascinating but small and less dramatic animals as well. Amphibians, including salamanders, caecilians, frogs and toads are among these. Some species are common and familiar: toads sitting under a street lamp, frogs hopping In a paddy field, frogs and toads singing from a garden pond, while others are rare and seldom seen.
To appreciate, and conserve the fauna we must understand it. To do that we must learn about it. Some things we can learn from books. Indian amphibians have been studied for many years. Both by students for scientific purposes and by other people who use their knowledge to exploit the amphibians for other ends such as food. In this book, Ranjit Daniels has brought together much of what we have learned about amphibians from books and from his own extensive experience with these animals in the field. He describes what is known about Indian amphibians and sets it in the context of what has been published about amphibians in other parts of the world.
No amphibians are as large as some mammals, birds, fish and reptiles but they do many interesting things. Amphibians are rather conservative in their diets. Most eat smaller invertebrates, mostly insects, which makes them welcome in farmers' fields where they may be important in eating crop pests. The protrudable tongue that a toad flips out to catch an insect, moves so quickly that it is impossible to see how it is done without high-speed photography.
In contrast to the rather standard diet is their breeding behavior. Among vertebrates only fish rival the diversity of amphibian breeding habits. Though most amphibians practice external fertilization, some do not. Courtship in amphibians is often impressive. Complex chemical secretions and elaborate mating dances are used by the newts. The vocal displays, with which male frogs attract mates, are often loud and diverse. Within a community each species of frog has a distinctive call which the females use to find and recognize males of their own species. The places where frogs and toads lay their eggs are also highly diverse. Some eggs are laid in the water, others on vegetation overhanging the water and in these cases the eggs hatch into aquatic larvae. In some cases, the eggs are laid on land and hatch into larvae that are washed into a nearby body of water. In other cases, the eggs hatch into tiny frogs, having passed through the larval stage in the egg. In still other cases, the eggs are fertilized in the mothers' body and develop there. These are just a few of the diverse ways that frogs breed.
If the eggs hatch into aquatic larvae they grow into a fish-like form in the water, sometimes reaching a relatively large size before metamorphosing into the adult form. It resorbs its tail, grows legs and hops out on land. The procedure happens, in some species, over a period of days and, as Daniels points out, makes a very effective classroom display.
There is still much to be learned about amphibians in India and around the world. There are many novel and exciting behaviors to be observed and described-some of them in quite common species. A scientist working in northern India recently discovered that in several common species females as well as males call during courtship. Perhaps because the calls of the females were much quieter than that of the males, these had not been described before. There are many more aspects of natural history of amphibians to be discovered and some can be found using no more elaborate equipment than a light, two eyes and a large fund of patience. They can be recorded using no more than a pencil and a notebook. Daniels, in the general sections of the book and in the species accounts, identifies things to look for. He also, with keys, descriptions and illustrations, provides the means to identify Indian amphibians. This book should be invaluable to anyone interested in amphibians and their natural history. It should be useful to students, teachers and interested amateurs. I think it is a valuable addition to the important series: India-A Lifescape.
Amphibians are considered to be the best indicators of environmental health. A decline in amphibian populations indicates ecosystem deterioration that might affect a wider spectrum of the earth's biological diversity. During the last 12 years there has been a great concern, worldwide, about the rapid decline in amphibian populations. Many reasons have been attributed to the loss of amphibians including habitat loss, UV-B radiation, global warming, toxic chemicals, pathogens that destroy the eggs and larval stages, direct harvest and others. Of these, loss of habitat seems to be the most significant factor, at least in tropical countries.
The various forms of habitat loss in nature that might affect amphibian survival have not been fully understood. The dependence of most species of amphibians on both land and water to complete their life-cycles has made the precise definition of habitat for each species difficult. Defining the exact habitat requirement of species of amphibians is further
complicated by our poor understanding of their patterns of distribution, their calls and behavior (that enable identification in the field) and the larval stages.
The study of amphibians in India has had a long history. The early works of G A Boulenger continue to remain the benchmark in the identification of Indian amphibians. While a number of publications have appeared during the last 100 years on Indian amphibians, there is very little material that is handy and presented in a style that is easy to use by both students and amateur naturalists. The present work is, therefore, an attempt to bridge some major gaps in the field study of Indian amphibians.
In this book, 72 species of Indian amphibians, including caecilians, have been described. These amphibians are those that are common and widely distributed in peninsular India and represent about one-third of all amphibian species known in India. The descriptions are simple and contain, although limited, details of other closely-related species, taking the actual number of amphibian species discussed to well over 100. That the life histories, larval stages and calls of many species are still not known should in itself be a challenge to students interested in the field study of amphibians.
Care has been taken in illustrating the book, using photographs and drawings that are accurate. The many illustrations provided throughout the species accounts and the illustrated keys should make it possible for students and amateur naturalists to identify amphibians in the field without much difficulty. To avoid the confusion that might arise from scientific names that keep changing, those names that have been the most consistently used in India have been retained in this book. However, all recent changes have been included as synonyms. Additionally, an appendix that lists out all the known species of Indian amphibians has been provided.
My career as a professional herpetologist began in 1989 while at the Smithsonian Tropical research Institute, Panama. Dr A Stanley Rand, who supervised my research on amphibians of the Barro Colorado Island, was the one who for the first time pointed out the need to develop simple guides to the field identification of amphibians. I am greatly honored by his foreword to this book.
My interest in developing simple guides to the field identification of Indian amphibians was further encouraged by experts at the Zoological Survey of India and the Bombay Natural History Society. Chief amongst these are Dr R S Pillai (ZSl) and Mr J C Daniel (BNHS).
Opportunities to work in the Western Ghats were provided by Professor Madhav Gadgil who was also the source of guidance while working on this book. I am grateful to him for choosing me to be one of the authors of the series of books that he has edited as part of the project Lifescape.
My wife Vinetha and my brothers Teddy and Dulip were of great service in the field and in managing live amphibians at home. Colleagues and friends have also contributed to this book in various ways. Jayshree Vencatesan extended her full support both in the field and while preparing the illustrations and the many drafts. A K Sharma of Centre for Wildlife Studies helped with the scanning of colour transparencies.
S K Dutta, Indraneil Das, M S Ravichandran, S G Sekar and S D Biju have helped with identification of species both in the past and now.
Field visits to the Western Ghats were made possible by B K Sharath, Surya Narayana Rao Addoor, P S Easa, D G Hegde, Simon Vasnaik and (not to forget) my philosopher friend V Ramakantha. Special thanks are due to Susan and Simon Vasnaik for their hospitality while I undertook field studies in Anaimalai Hills within the Tata Tea Estates in Pacchamalai. D G Hegde introduced me to the Anaimalai Biodiversity Conservation Association and provided logistic support for my field studies in Valparai. Besides Tata Tea and Hindustan Lever (both in Valparai), Glenbeck Estate (Kanykumari district) and Neria Estate (Dakshina Kannada district) welcomed me to do field studies within their estate premises.
Photographs used in this book as plates and for preparing the drawings were provided by E Kunhikrishnan, T V Guruprasad, Gundappa, K A Subramanian, S V Krishnamurthy, P S Easa, C P Shaji, Saju Abraham, S Karthikeyan, Kushal Mukherjee, Kaushik Deuti, Ananda Banerjee, Brij Kishore Gupta, S D Biju, S Babu, R Arumugam, K Chandrasekara and Surya Narayana Rao Addoor. Besides these, I heavily relied on the excellent photographs published by the Wildlife Heritage Trust of Sri Lanka in the book The Amphibians of Sri Lanka, Madras Crocodile Bank in their journal Hamadryad, the Journal of Bombay Natural History Societv and Records of the Zoological Survey of India. Much of this material was available at the Chennai Snake Park. The posters published by the Coimbatore Zoological Park, Kerala Forest Research Institute and Wildlife Institute of India were of great help as well.
Finally, the financial support provided by the Ministry of Environment and Forests, Government of India and the Seed Grant for the year 2002 provided by the Declining Amphibian Populations Task Force of the IUCN are gratefully acknowledged. My field study in the Western Ghats during the early 1990s was supported by the Indian Institute of Science, through a Senior Research Fellowship.
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