Perungulam Wetland- A significant Avian Biodiversity Site in Thoothukudi, India: A Seasonal Avifaunal Assessment and Potential Conservation Implications

Many unprotected wetlands lack biodiversity assessments, even though they have immense potential to support multiple taxa. Hence, towards closing this research gap, we conducted a comprehensive seasonal avifaunal diversity assessment at Perungulam, Thoothukudi district of Tamil Nadu, India, from July 2023 to June 2024. The aim was to document avifauna, seasonal composition, abundance, and potential threats. Community structure and seasonal bird assemblages were analyzed using alpha and beta diversity indices, indicator species analysis, and non-metric multidimensional scaling (NMDS). A total of 147 bird species (22 orders and 60 families) were recorded. Passeriformes was the most abundant order with the highest number of families (n=23) and species (n=40), followed by Charadriiformes (9 families and 28 species) and Pelecaniformes (4 families and 16 species). Scolopacidae family recorded the greatest number of species (n=13), then Ardeidae (n=11) and Anatidae (n=10). Resident species constituted the largest proportion (n=100), followed by winter visitors (n=35). Majority of species were Least Concern (n=140), with seven species: Indian Roller Coracias benghalensis, Spot-billed Pelican Pelecanus philippensis, Bar-tailed Godwit Limosa lapponica, Black-tailed Godwit Limosa limosa, and Asian Woollyneck Ciconia episcopus (Near Threatened), Egyptian Vulture Neophron percnopterus (Endangered), and Curlew Sandpiper Calidris ferruginea (Vulnerable), falling under the threatened category. Most species were enlisted under the Indian Wildlife Protection Act (WPA) Schedule II (n=132), and Schedule I (n=14). The highest overall species richness was in Wetland (n=88), followed by Open Scrub (n=56), Grassland (n=40) and Trees (n=21). Seasonal beta diversity showed moderate species turnover (22–39%), driven mainly by species replacement rather than nestedness. This pivotal study, which documented potential threats, highlighted the urgent need for habitat protection and provided data for any future management plan for wildlife managers to use to strengthen conservation measures.