Bangladesh’s major river systems, particularly the Padma and Jamuna, support highly dynamic sandbars (chars), mid-channel islands, floodplain wetlands and riverine grasslands that together form one of the country’s most important yet under-recognised ecosystems. These shifting landscapes provide breeding, roosting and foraging habitat for migratory and resident waterbirds, including globally threatened species such as the Endangered Black-bellied Tern and Indian Skimmer. At the same time, tall floodplain grasslands dominated by Saccharum support grassland-dependent species such as the Vulnerable Bristled Grassbird, highlighting the ecological connectivity between river channels and adjacent grassland habitats. Despite their high biodiversity value, riverine ecosystems have historically received limited formal protection. Conservation efforts in Bangladesh have largely focused on forests, mangroves and wetlands, while dynamic river channels, sandbars and associated grasslands remain underrepresented in the protected area network. As a result, critical breeding sites and riverine grasslands continue to face increasing pressure from land conversion, disturbance and habitat alteration, underscoring the need for systematic identification and site-based protection.