Status and Population Trend of Chiropterans in Southern Assam, India

Abstract

Population survey plays an important role in understanding the census structure of any species in a particular area. Chiropterans are an important groups of mammals found almost all part of India. Chiropterans (including Mega and Microchiroptera) are important as they have ubiquitous distribution in almost all the states of India, from Kashmir to Kanyakumari and from Gujarat to Arunachal Pradesh. They play important roles in all types of ecosystems. Mega chiropterans largely help in pollination, while microchiropterans help in pest control through insectivory. To understand the population structures, the status of bat population and its trend in Cachar district (Assam) north East India was studied. A total of six species and 97 roosting sites were found over approximately 3786 square kilometer of area. The colony size of Pteropus giganteus was found to consist of 13 to 723 individuals, for Cynopterus sphinx it was recorded as 2-9 groups having 8 to 51 individuals (with group size 3 to 8 individuals), for Eonycteris spelae it was 400-600 individuals, for Pipistrellus coromandra, it was very less, as group size was found to be of 3 to 6 individuals and for Megaderma lyra the number recorded was 5 to 128 individuals. Population structure and the prevalence indicate this zone to be a potential area for maintaining a viable population of bat species. Since no prior systematic information on the Chiropteran population is available from the area, the present study will help in formulating conservation plan of the much neglected group of nocturnal mammals.