Mr Stephen Moss 
Understanding Bird Behaviour [PDF ebook] 

The way birds behave is one of the vital keys to accurate identification and this book provides the experienced instruction needed to understand and get the most out of watching bird
s.
The guide covers all the fundamental types of bird behaviour, including movement, feeding, breeding, migration, navigation, distribution, range, life and death, all of which are illustrated with beautiful photographs.
There is a whole section dedicated to the behaviour of different species groups, from divers and grebes through to sparrows, buntings and finches.