Avifaunal diversity and conservation status of waterbirds in Pillaimadam Lagoon, Palk Bay, India

Avifaunal surveys are important for developing targeted conservation strategies for specific sites and species, especially in undocumented critical wintering grounds for shorebirds within the Central Asian Flyway. In this context, we present a first-time avifaunal checklist at the Pillaimadam Lagoon, Ramanathapuram District, Tamil Nadu. A total of 108 species of birds belonging to 43 families under 16 orders were recorded. Order Charadriiformes was the most prevalent (34 species), followed by Passeriformes (28 species), and Pelecaniformes (15 species). Family-wise, the highest species richness was recorded for Scolopacidae and Laridae (11 species each). Winter visitors accounted for 33.3% (36 species), with other categories including Resident (51 species), Resident/Non-Breeding (17 species), Local Migrant (3 species), and one Passage Migrant—Rosy Starling Pastor roseus. The lagoon harbours five ‘Near Threatened’, two ‘Vulnerable’, one ‘Endangered’ (Siberian Sand Plover Charadrius mongolus), and one unassessed species (Hanuman Plover Charadrius seebohmi) as per the IUCN Red List of Threatened Species, and 35 species enlisted in Appendix II of the Convention of the Conservation of Migratory Species of Wild Animals (CMS), emphasizing the need for conserving this coastal wetland as a ‘protected area.’ Hence, the current baseline data on avifaunal diversity is the first comprehensive bird list from Pillaimadam Lagoon.