Rajendra Singh, Amit K. Singh, Nidhi Sharma and Nirupama Dash
Abstract
Wetland ecosystems are among Indiaâs most biologically productive habitats, offering critical ecosystem services and supporting exceptional avifaunal diversity. In northern India, the wetlands of Uttar Pradesh (UP) and Uttarakhand (UK) together form an ecologically interconnected landscape that includes the Gangetic floodplains, teraiâbhabar zones, Himalayan foothill wetlands, oxbow lakes, marshes, reservoirs, and high-altitude lake systems. These diverse environments serve as vital breeding, feeding, roosting, and migratory stopover sites for a large proportion of Indiaâs bird species, including several threatened and globally important migrants. This review synthesizes current knowledge on avifaunal richness, ecological significance, threats, and conservation needs across major wetland sites in UP and UK. Uttar Pradesh supports an extensive network of riverine and floodplain wetlands associated with the Ganga and Yamuna basins. Important sites such as Nawabganj, Sandi, Sarsai Nawar, Parvati Arga, and Sur Sarovar-many of them Ramsar-listed-host large congregations of migratory birds each winter. Species such as the Sarus Crane, Bar-headed Goose, Northern Shoveler, and numerous waders depend heavily on these habitats. Uttarakhandâs wetlands, including the Asan Conservation Reserve, Nainital Lake, Bhimtal, Sattal, and various reservoirs and high-altitude lakes, support rich assemblages of waterbirds, raptors, passerines, and trans-Himalayan migrants. Both states form essential components of the Central Asian Flyway (CAF) by providing habitat connectivity critical for the survival of migratory avifauna. The review highlights ecological factors that regulate bird diversity in these wetlands, including hydrological cycles, vegetation composition, food availability, and human disturbances. Research across both states shows significant species richness and pronounced seasonal variation, reflecting the ecological sensitivity of these wetlands. To address these challenges, the review recommends integrated conservation approaches centred on community participation, habitat restoration, catchment management, and strengthened protected area networks. Enhancing Ramsar Site management, improving hydrological regulation, and adopting modern monitoring tools including satellite tracking, drone-based surveys, and citizen science databases like eBird can greatly support data-driven decision-making. Policy priorities identified include stronger implementation of the Wetland (Conservation and Management) Rules 2017, improved cross-state coordination between UP and UK, and greater support for long-term ecological research and bird monitoring programs.