Migration is the seed of diversity. We human beings migrate for the better living standards. Similarly birds migrate towards fruitful conditions for their progeny. Till now there is no strong theory of how birds migrates what factors they are considering during migration, etc. The difficulties during migration are the major challenge they undergo. This book gave a great insights about bird migrations. This book belongs to federal department of United States, so it covered only their region specific birds and their migration. Yet it is good for beginners in the field of orinthology