Abstracts

Further information on the fauna of silent valley. Two more faunistic surveys were carried out in the silent valley reserve forests after the submission of the report on the earlier expedition in 1979. The second expedition was under taken with the object of assessing the faunal wealth of the valley with special emphasis on the submergible area. Many more examples were collected and further observations made a brief account of, which is presented here. It has to be admitted that the information gained on the fauna is far from complete. It has served to illuminate the need for undertaking detailed ecological, experimental, genetical, palaeontological and soil studies along with the taxonomical studies which the zoological survey of India is conducting. To gain a closer understanding of the life of the system that exists in the ecosystems like a tropical rain forest. These studies have, however, revealed that the silent valley fauna is both rare and unique. Rare, because similar animals which inhabited all over the western Ghats once upon a time have been lost due to destruction of their habitats by mans intrusion into them .It is unique because what has been collected has proved to be of immense scientific interest both from the taxonomic and zoogeographic point of view. More examples belonging to various insect orders have been collected. Coleopteron families such as Rjhiozoidae, Cicindelidae, Carabidae, Dytisscidae, Gryinidae < Staphylinadea, Passalinadae, Lucanidae, Tenebrionidae, Buprestidae, Chrysomelidae, Curcurlinidae etc. have been collected in large numbers. Many more examples of Odonotes. Hymenopterans, Dipterans etc. have been added. Populations of aquatic bugs have been noticed to be lentriful. The cicadae which were absent in the valley during the earlier expedition have been collected. Popualtions of Cicadae have evidently moved on the Silent Valley proper from the surrounding areas. Several species of Dictyoptera have also been collected which fact is interesting because they are reported to occur in large numbers only in geologically old areas. A good collection of Membracid bugs have been made, a study of which revealed the existence of a new genus and five species. They constitute a group of potential carriers of plants diseases. An interesting species of spider, which could remain, submerged for as many as four minutes has been noticed. A new subgenus has been reported by a specialist working on scorpions. The fish fauna has been noticed to be richer, 22 species having been collected. Three of them are new to science. Further collections have undoubtedly established Silent valley as a haven for Amphibia. In addition to the two species described earlier, two more new species have been discovered. The torrent toad belonging to the genus Ansonia deserve special mention. After the discovery of a single species of the genus by Gunther in 1875, no more specimens were taken. Many amphibia which have become rare or absent in other parts of Western Ghats have been collected after considerable gap of 50 -80 years. A few adults of the primitive Caecilians have also been collected. As unique type of tadpole which lives permanently in the thin film of water on vertical granite slopes have been discovered. Studies on its adaptational modifications, life history of its adult should be made. The painted bat which is very rare has been discovered from the valley after a considerable life span of time along with some other species. Presence of tiger, leopard, some of the lesser cats, bear, civet and porcupine was noticed. Some attention was paid to the study of littler ecosystem on the shoreline. The soil fauna composed of Collembla, Isopoda, Dictyoptera and Dipteran larvae. Annelida, Myriapoda, Spiders, Diplura, Coleoptera and its larvae, Gryllids, Isoptera and Hymenopterous groups were also present. Preliminary studies show that the population of litter organisms is inversely proportional to altitude, the maximum concentration being detected between 920 and 980 meters above the sea level. Apart from the above, preliminary observations on the existence of intraspecific variations were made in certain groups were collected. Many species with Indo-Malayan affinities were collected. These include Hemipterous bugs such as Carbula, Plantia, Antestia and Placosternum spp and Odonates, Aciagrion hispoa, Trithemus, Aurota etc. Two genera of fish such as Batasio and Danio have close relatives in Malay Archepelago. Specialized studies which are in progress on many groups are likely to bring out mainly more species hitherto unknown science. The fauna inhabiting the shore line of Kunthi river system has also been noticed to be drawn mainly from the following groups : Arachinida, Odonata, Dictyoptera, Heteroptera, Coleoptera, Amphibia, Reptilia, a variety of birds which nest on shore line vegetation and a few mammals like other and mongoose. It may be side in conclusion that what little has been collected and studied serves to highlight the magnitude of what remains to be collected and studied.