RESEARCH ARTICLE Tropical Ecology https://doi.org/10.1007/s42965-025-00383-y species (Getzner 2002) including birds. Wetlands play a crucial role in maintaining bird communities by supply- ing abundant resources (Melkin et al. 2022), as a variety of microhabitats offer year-round food supply along with abundant and high-quality shelter for resident and migratory birds (Mitsch and Gosselink 2000; Saruman et al. 2017). Waterbirds are often sensitive to wetland changes and are considered the most important indicators of ecosystem health (Bibby 1999; Wang et al. 2020; Li et al. 2021), and might be expected to adversely respond to changing wet- land characteristics (Haig et al. 2019). The 2018 Global Wetland Outlook reports that the wet- land area continues to decline in all parts of the world, with conversion and loss continuing (Convention of Wetlands 2021). Recent estimates suggest an 87% decline in global wetland areas since pre-industrial times (Walpole and Davidson 2018). The major drivers of change in wetlands include land-use change, including water extraction, exploi- tation, and the side effects of pollution, with the impacts of climate change and invasive species becoming more Introduction Wetlands are among the most productive and valuable eco- systems in the world and are natural reservoirs of biodi- versity (Baigun et al. 2022). They play critical ecosystem roles, such as hydrological balance, pollution control, and biodiversity conservation (Woldemariam et al. 2018). Rich in biodiversity, wetlands harbour many globally threatened  Sharat Kumar Palita skpalita@gmail.com 1 Department of Biodiversity and Conservation of Natural Resources, Central University of Odisha, Koraput, Odisha 763004, India 2 Department of Agriculture and Allied Sciences (Zoology), C. V. Raman Global University, Bhubaneswar, Odisha 752054, India 3 Centre for Ocean, River, Atmosphere and Land Sciences (CORAL), Indian Institute of Technology, Kharagpur 721302, India Abstract Wetlands are one of the productive ecosystems and are important for water birds in terms of food, nesting and rearing of the young ones. We evaluated bird species richness and abundance in four tropical wetlands (two lentic and two lotic) from October 2016 to September 2017 located in the Central Asian Flyway in Koraput District in the southern part of Odisha state, Eastern Ghats, India. Using diurnal surveys and point count method in three seasons (pre-monsoon, monsoon, and winter), 40 species of aquatic birds with maximum waders belonging to seven orders and 15 families were recorded of which 28 and 12 species are resident and winter migrant birds respectively. Oriental Darter (Anhinga melanogaster) is considered Near Threatened as per IUCN Red list, while Anatidae and Ardeidae are the two most speciose (17.5% each) families recorded. Species richness and abundance of birds were significantly higher (p < 0.05) in the winter season with a large influx of migratory birds, mostly Anseriformes. The two lentic water bodies accounted for higher species richness compared to lotic ones, serving as good wintering grounds for the migrants. The satellite-derived images and their cor- responding indices revealed seasonal change in water bodies and their surroundings for the pre- and post-rainy seasons indicating potential habitats for bird population. This study demonstrated the importance of seasonality on the bird assem- blages for resting, feeding, and roosting, particularly for winter visitors in wetlands of the Indian Eastern Ghats. Situated along the Central Asian Flyway, these wetland habitats deserve conservation to serve as better functional ecosystems. Keywords Koraput · Migratory bird · Seasonal variation · Southern Odisha water birds · Winter migrant Received: 12 April 2022 / Revised: 25 April 2024 / Accepted: 2 April 2025 © International Society for Tropical Ecology 2025 Diversity and assemblage of birds in tropical wetlands of Eastern Ghats, India: a call for conservation prioritisation Sharat Kumar Palita 1  · Kranti Titikshya Samal 1  · Swetashree Purohit 2  · Anirban Mahata 1  · Mukunda Dev Behera 3 1 3 International Society for Tropical Ecology