Avifaunal diversity in disturbed and undisturbed winter forests of Gogona Forest Management Unit, Wangdue Phodrang

Abstract

Bhutan lies in the Eastern Himalayan ecoregion and is identified as part of the 10th global biodiversity hotspot. The baseline data for bird conservation on species richness, abundance, and diversity of avian in Forest Management Units (FMUs) are, however, inadequate because of a conservation focus on rare and endangered species. The objectives of this study were to compare the avian richness, abundance, and diversity to analyze the effect of vegetation parameters on avian species diversity and composition in disturbed and undisturbed habitats in GFMU in one winter season. The Open Width Point Count method was used to sample birds along the established transects. Quadrates 20 m x 20 m were used to sample vegetation, with 30 quadrates in each habitat type. A total of 71 avian species belonging to 28 families were recorded. A higher avian diversity (Hʹ = 2.95), species richness (S = 22) and abundance (n = 1150) were observed in the undisturbed habitat than disturbed habitat (Hʹ = 2.85), (S = 15), and (n = 809). Moreover, correlation of vegetation parameters such as canopy cover and shrub cover with avian diversity and avian composition revealed a medium association in undisturbed habitat. Further, there was a statistically significant difference between the disturbed and undisturbed habitats on avian diversity and composition, signifying that both the habitats are vital for avian conservation. A long-term study is needed to indicate variations in species composition and diversity caused by the existence of migrants, by breeding, and by effects of the other season in both the habitats.