Resumen
Diversity and distribution of avifauna was studied at the tropical montane cloud forests of Horton Plains National Park, situated in the highland plateau of the Nuwara Eliya district from September 2015 to May 2016. Three main habitats were identified; cloud forest habitat, cloud forest die-back habitat and grassland habitat. Nine, 300 m line transects were marked in each of the habitats. Avifauna was recorded on three consecutive days of each month while travelling along these transects. Seventy eight species of birds were recorded during the study period. This included 66 resident species (with 13 endemic species) and 12 migratory species. The maximum value of the Shannon Wiener Index H' of 2.56 was recorded from the cloud forest habitat. In the cloud forest die-back habitat the H' was 2.49 and in the grassland habitat the H' was 2.31.The Jaccard similarity index, between cloud forest and cloud forest die-back was 0.58, and these two habitats had more common species. Cloud forest is the major habitat to be protected, with other habitats, in HPNP. Hence management of the HPNP should plan more actions to improve long term monitoring plans to warrant the protection of threatened species.Keywords: bird diversity and distribution, endemic birds, Horton Plains, tropical montane cloud forest