Mammalian persistence and conservation priorities in a fragmented tropical refuge of Bangladesh

Global mammalian diversity is declining rapidly due to habitat loss, fragmentation, and weak enforcement of conservation measures, raising fundamental questions about species persistence in human-modified landscapes. Protected areas serve as critical refuges, yet many in South Asia are small, degraded, and embedded within heavily human-dominated settings. In Bangladesh, Inani National Park supports iconic mammals, including the Endangered Asian Elephant and the Western Hoolock Gibbon. Despite serving as a corridor, the refuge’s conservation efficacy under increasing pressure remains poorly understood. To assess drivers of persistence and inform spatial management, we conducted a year-long survey (November 2022–November 2023) combining systematic line transects and extensive camera trapping (4771 trap-days). We documented 23 wild mammal species, including three globally Endangered and four Vulnerable taxa. Habitat gradients strongly shaped persistence: shrublands supported the highest richness, peaking in the monsoon, whereas plantations and modified habitats were least rich and diverse. Occupancy modelling revealed sharp contrasts in site use: the Asian Elephant showed near-complete occupancy (ψ = 1.00), whereas elusive carnivores such as the clouded leopard were rarely detected (ψ = 0.24; p = 0.04). Our findings highlight INP’s role as a key refuge and corridor, but also threats from deforestation, encroachment, and livestock grazing. Conservation priorities include restoring degraded habitats with native vegetation, strengthening boundary protection in high-diversity zones, and implementing community-based measures to mitigate human-elephant conflict. Targeted, evidence-based interventions are essential to secure the long-term persistence of Bangladesh’s priority mammal community.