Carol Inskipp & Richard Grimmett 
Field Guide to the Birds of Bhutan and the Eastern Himalayas [PDF ebook] 

The definitive guide to the birds of Bhutan, Sikkim and Arunachal Pradesh The nation of Bhutan and the Indian states of Sikkim and Arunachal Pradesh together form the eastern arm of the Himalayas. This book is the definitive field guide to the birds of this magical corner of Asia.This field guide covers all 809 species that regularly occur in the region, including most vagrants. There are 152 superb colour illustrations, with concise text on facing pages for quick and easy reference covering essential identification information such as voice, habits, habitats, distribution and status.The introduction further includes information on popular birding sites and conservation.