Bird Diversity and Factors Affecting Bird Abundance at Dullu Municipality, Dailekh, Nepal

Abstract

Seasonality, social disturbances, and availability of ecological requirements play an essential role in bird distribution, diversity, and survivability in any ecosystem. The study was carried out in Dullu Municipality Dailekh District to identify the bird diversity and factors affecting bird abundance. The point count method was used for bird surveys during the winter and summer season of 2020. Altogether 98 bird species belonging to 11 orders and 38 families were recorded. The highest species richness was found for order Passeriformes and Muscicapidae family. Among recorded species, the higher species richness of birds was found during winter than summer season, and 52 bird species were observed at both seasons. The winter season had more diverse bird species than summer; however, these were more evenly distributed in summer than in the winter season. Among 98 species, the higher bird species were resident, followed by winter migrants, summer migrants and passage migrants. Himalayan Vulture (Gyps himalayensis) and Alexandrine Parakeet (Psittacula eupatria) were threatened species found in the study area. Forest habitats had more diverse bird species than agricultural land. Different environmental parameters such as nearest distance to the water source, canopy cover, and nearest distance to forest habitat had a significant effect on bird occurrences. The species richness was positively correlated with the nearest distance to agricultural land for both seasons; however, it decreased with increasing distance to water source and canopy cover. In Dullu Municipality presence of migratory, residential, endemic, and threatened bird species indicated the uniqueness of the bird habitat in the area; therefore, a site-specific management plan is necessary to conserve these bird species.