Owls are enduringly popular birds, but due to their nocturnal habitsmost species are difficult to see well. The plumages of many speciesare cryptic and difficult to separate by plumage alone. This problem iscompounded by the different morphs that many adopt. This book fullydescribes every known species and subspecies of owl, as well aspresenting the latest evidence on owl taxonomy, based on DNA work andvocalisations. Because voice is vital in owl identification, muchemphasis is placed on it in the book and sonograms are provided formany species. A CD of owl vocalisations will accompany the book.