Roost Selection and Diet Analysis of Leschenault's Rousette Bat (Rousettus Leschenaulitii Desmarest, 1820) in Bhimad Area Tanahu, Nepal.

Abstract

Bats are mammals belonging to the order Chiropteran the second largest to the order among 26 mammalian groups. Bats are the only mammals capable of true and sustained flight with their forelimbs adapted as wings. The main objectives of this study were to identify cohabitant bat species with Rousettus leschenaultii at the study cave, determine population

and

evaluate factors influencing roosting refugia, enumerate diets of Rousettus leschenaultii at the study area Bhimad, Tanahun Nepal. Possible roosting sites were surveyed and mist netting was used to capture bat and observed directly. Morphometric measurements, taxonomic characters, were used to identify species. High resolution photographs were taken to estimate the population. The height of roost site, distance of roosting sites of bats inside Chamero cave was measured using measuring tape (Pythagoras theorem). The seeds of potential food of fruiting plants, mostly ripe fruits were collected. Plastic sheets of 1-1m size were placed randomly in six different locations inside the cave to collect fecal matters of bats. Total 156 fecal samples were collected from the Chamero cave twice in a month.The correlation between population and height of roost refugia, distance of roost refugia from cave entrance were analyzed using correlation in R-studio. Also, regression analysis was performed to analyze relation between bat population and physical factors. The collected samples of guano were analyzed using collected potential food items. The family wise composition of diet items were analyzed using MS Excel 2010. A total four roosting sites were identified with eight species of bats. The height of roosting refugia and bat population was found to be moderately correlated (r=0.55) whereas, distance of roosting refugia from cave entrance and bat population was found to be in a weak correlation (r=0.44). Among four roosting sites Bhalu cave has the highest diversity of bat species with being longest cave. The bat species were found to be roosting in the highest refugia inside Chamero cave. The distance of roosting refugia from cave entrance don’t have any effect on roosting refugia. Thirty three plant species were collected as potential diets from 20 families. A total of 11 species of fruiting plant were identified as diet of Rousettus. Among these twenty five percent were found to be cultivated fruits and 75% were found to be wild fruits. This study on the diversity and habitat of bats can help understand the ecological interaction. This can enhance knowledge of locals especially farmers about importance of bats.