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Disscussion Globally 1001 species of bats are reported of which 167 species belong to suborder Megachiroptera and remaining 834 species belong to suborder Microchiroptera (lUCN red list, 2001). The order chiroptera thus is the second largest aggregation of mammals (lUCN red list, 2001). Indonesia is the country of Indomalayan region, which has the highest number of bat species (175 species of bats). The diversity of bat fauna in India is remarkable; about 114 species of bats are reported, of which only 17 species belong to sub order Megachiroptera and 97 species to sub order Microchiroptera. Thus the latter sub order is remarkable for the species diversity. Most of the bat species of India are reported from hilly region of North-East and Western Ghats. The Indian bats comprise 11.6 % of World bat species (Mistry, 2001). Seventy three bat species are reported as cave species in Indian Sub Continent (Bates & Harisson, 1997). In India 61 species of bats are reported as cave species. North East region is the highly preferred region as compared to the Western Ghats, as this region of Himalaya and North-East part of India has about 52 cave bat species on its record. About 50 bat species are reported from the entire Western Ghats region since last century. A long list of publications is available mentioning records of bat species in India, but the contribution of Wroughton in early decades of previous century (under Bombay Natural History Society's mammalian survey published in series of publications) and Brosset (1962a, 1962b and 1962c) is noteworthy. Of the 50 bat species reported from the Western Ghats of India, 35 species are reported as cave species (Bates & Harisson, 1997), the richness of cave bat species of Western Ghats of India thus is substantial. The study area though is a fragment of the Western Ghats of India, the findings of the present survey is quite satisfactory. In the present survey 30 bat species are reported from the central part of the Western Ghats of Maharashtra, extending from Bhimashankar in North to Mahabaleshwar in the South (Report submitted by Korad V. S. to Ministry of Environment and Forests, 2005). Of the 30 bat species 21 species are reported from the caves, which comprise 11 % of the total cave bat species reported at the sub continental level and 34.43% at the national level. 58 The northern part of the Western Ghats to which the study area belongs, is different in topography, climatic conditions and forest pattern in comparison to its southern counterpart. This part of Western Ghats is relatively hot, dry and of low altitude. (While the southern part of the Western Ghats is relatively humid due to heavy rain fall and richness of the forest due mainly to its inaccessibility. The diversity of species in southern Western Ghats region hence ought to be higher). The survey and analytical study of results of cave bat species is assumed to help in understanding the ecological condition of the forest concerned. The record of 30 bat species during the present survey may be the result of extensive survey performed exclusively for bat species. Though the bat species diversity in general seemed satisfactory in the study area (as compared to any other taxa of the small mammals), the rate of destruction to the forest area appeared to be remarkable. The present study aims at understanding the pattern of distribution and trend of adaptability in the cave bat species in particular and the bat fauna in general. The study area is categorized on the basis of altitude, rain fall and forest pattern. Among the three regions of the study area, the hills of high altitude seem to be most suitable for cave bats, as the cave formations are highest, the rain fall is remarkable and hence the forest of evergreen or semi evergreen type help to maintain high relative humidity in the surrounding and the microhabitat of the cave bats. The abundance of the food plants for frugivorous bats and richness of the insect fauna in the forest area for insectivorous bats seem directly concerned with the richness of bat species diversity. Twenty cave bat species (about 96.23% of total cave bat species from study area) are recorded from this particular region. On the contrary, the western part of the study area- the Konkan region has recorded the least number (only seven) of the cave bat species. This particular region of the study area is confined to the steep hills of western side, which is poor in cave sites, water holes are less in number and most of them are seasonal. The mixed forest in this region has sparse canopy. Due to steepness of the hilly region, irrigation system is also not well developed in this area. These observations indicate that relative humidity of the surrounding; suitable habitats and density of the forest are some of the prime limiting factors for species diversity of cave bats in the Northern Western Ghats region. 59 The low altitude spurs of the eastern side of the study area recorded ten cave bat species, which comprises 47.62% of the cave bat species of the study area. Though this region has low rain fall, the surrounding is hot and dry, the canopy of the deciduous forest though dries up in hot summer, provides niche to cave bats for their survival. The sacred grooves, old temples and tunnels leading to dams are plenty in this region and provide the most suitable sites to cave bat species for day roosting. The forests in some of the parts of this region come under private sector and hence are well protected. The irrigation system in this region seems to play a vital role in richness of the flora and fauna Jn general. Only one gregarious frugivorous species recorded from the study area is a remarkable finding. The forest pattern of the study area seems unsuitable to other frugivorous cave bat species like Eonycteris spelaea, which feeds mainly on nectar and pollens of evergreen forest plants (Andersen, 1912; Start & Marshall, 1976; Gould, 1978; Bhat at el, 1980; Kunz, 1988; lKunz_at ei„ 1994\ Wolton at el., 1982). Another frugivorous cave bat species of thesClithenrWeMem Ghats is Latidens salimalii; the critically endangered endemic species of the continent, which confines to the high altitude caves of High Wavy Mountains in Tamil Nadu state of India (Bates et ai, 1994d). This species feeds on a wide variety of hard fruits and seeds. The habitat preference of this species thus closely related to its highly specific need of food and foraging ground. According to Hill & Smith, (1984) exceptionally the frugivorus bats of family Pteropodidae live solitarily {Melonycteris & Nyctimene), while rest of the species of this family form smaller and more frequently larger groups of few thousand to several thousand individuals. Usually they roost in trees and other foliage; exceptions are greater necked backed fruit bat Dobsonia moluccensis (which frequently occupy the twilit gallery near the cave entrance) and Rousettus species (which prefer deeper caves and darker corners of tomb). In concordance with these statements of Hill & Smith, (1984), the fulvous frugivorous bat Rousettus leschenaulti in the study area is reported from deep and dark caves, tunnels and old temples. This cave bat species can survive at relatively dry and hot climatic conditions and depend on large variety of food plants and their products (iMc Cann, 1941b;, Brosset, 1962a; Bates at el., 1994a). In the present survey it is discem^'that it has adapted itself to man made constructions like dam tunnels in the spurs region. They are also observed performing seasonal 60 migrations depending on the conditions of the forests on which they depend for feeding. The only truly carnivore bat species found in the study area (the greater false vampire bat Megaderma lyra) occurs in small groups in caves of higher altitude. But the colonies appear more frequently and of larger size at lower altitude near the agricultural land. The observations indicate availability of better feeding grounds for this species at low altitude. This species is reported feeding on insects and small vertebrates including fishes, reptiles, lizards and small bats (A^vani, 198l)^^a 1986^ This speoes is reported to co-exist with other bat species in caves, such as Hipposideros fulvus, Hipposideros speoris, Rousettus leschenaulti, Rhinopoma hardwickii, Tphozous katchensis, Rhinolophus sp. (Gopalakrishna & Badwaik, 1989; Kunz, 1982), but during recent survey only one site is reported showing its coexistence with Rhinolophus rouxii. The lesser false vampire bat Megaderma spasma on the other hand is ranked as Least Concern (LC) (CAMP Workshop, 2002) being widly distributed, but in the present survey this species is reported to have very restricted distribution in the evergreen forest of the southern part of study area. It is also reported in the human vicinity. This species is geographically wide spead, but never found in abundance and its population is vulnerable to the destruction of its forest habitat (Bates & Harisson, 1997). The mouse-tailed bats of Genus Rhinopoma sp. are not discerned in the study area. These cave bats^argreported from the dry and semi desert hills (Siddiqui, 1960^^0 "^ajuria, 1979^. Similar habitat conditions are required by most of the '^eath tailed bat species of Genus Taphozous (Brosset, 1962a; ^diquiri9?lVKhajuria, 1953; 1965 &ri979a!)984!'^ ^Inha, 198TayWhitekar, 1993, 1995a, b.). Taphozous longimanus islEeoiriy species of this genus reported from the study area. Again its distribution is confined to the mixed forest of the western part- the Konkan region. These cave bat species is also reported from the human vicinity and observation gallery of the bridge at riverside. Similar habitats are reported by Brosset, (1962a) and Wroughton & Ryley, (1913).

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