Assemblages of bat species are structured by the interplay of abiotic and biotic factors, which change dynamically across space and time. From the perspective of space, an assemblage is expected to uniquely correspond to a land-use type. Northeast India hosts two biodiversity hotspots and a variety of land uses, but ecological studies on bat assemblages are lacking. Bats make up the second most diverse mammalian order, with 1447 species, out of which 87% possess the ability to echolocate. Urban regions followed by rural regions represent the highest form of anthropogenic landscape modification, while natural regions like protected areas, reserve forests, etc. represent the least modified. This study aims to characterize the echolocating bat assemblages in the tropical lowlands of Assam and Arunachal Pradesh. I will investigate the response of foraging bat assemblages to different levels of landscape modification in terms of change in species diversity, species composition, and activity. Habitat, disturbance, roosts, and prey are known to be the key ecological drivers of assemblage change. Depending on the preferred foraging mode and morphology, a bat species is best adapted to a particular type of prey and foraging habitat/background. Therefore, whether the diversity of prey and spatial niches i.e., habitat are positively associated with species diversity will be examined. The temporal dynamics of disturbance and resource availability are expected to vary across the regions. On that account, I will determine if assemblage and species-wise bat activity patterns also differ in different regions. Detecting bat echolocation calls enables one to non-invasively monitor bats in the field. Since echolocation calls are mostly conserved and can be used for species identification, I will establish a regional call library by recording captured bats. Passive acoustic monitoring (PAM) methods will then be used to realise the above-mentioned objectives.