Assessment of winter migratory waterbirds diversity and distribution in Asan Conservation Reserve, Uttarakhand (Western Himalayas), India

The current study presented information on waterbird diversity in the Asan Conservation Reserve (Western Himalayas), India. The waterbirds survey was conducted from October 2023 to April 2024 in and around the ACR, Dehradun, India. The findings revealed that 47 wetland bird species from 13 families and 8 orders have been observed during the study. Out of a total of 14 winter migrants (WM), 14 residents (R), 11 residents with local migrant (R/LM), 3 residents with influx and passage movement (R/WM/SM), 2 residents with altitudinal winter movement (R/AM/WM), one species is winter migrant with passive migration (WM/PM) and one species is resident with summer and winter movement (R/SM/WM) observed during the study. The Anatidae family has the most species (15) and the maximum relative diversity value (31.91). The result of Bird Species Diversity (BSD) showed that the value of BSD was highest (2.49) in December compared to other months. Similarly, the analysis of Bird Species Richness (BSR) showed that the maximum BSR was found in December (5.96) when compared to other months. The results showed that the Eurasian Coot was the most dominating species, accounting for 23.11% of overall abundance when compared to other species. A total of 23 omnivorous, 17 carnivorous, and 7 insectivorous species were recorded based on their feeding guilds. During the study period four threatened species were observed as per IUCN. Out of total three species such as River Lapwing, Painted Stork, and Ferruginous Duck were listed as Near Threatened (NT), one, Pallas’s Fish-Eagle as Endangered (EN), and the remaining 43 as Least Concern (LC) in the IUCN Red data book.