My hawk identification skills are woefully inadequate. Hawk watchers are a rare breed and their ability to make accurate identifications of birds from extreme distances seems at times like a form of magic. As with all magic, however, if you know the tricks things become a lot less mystical.
Traditional field guides are not terribly helpful when it comes to identifying hawks in flight. Hawks tend to be far away, either off in the distance or way over head and lighting conditions are frequently less than ideal. Hawks in Flight is written by three of the most respected authority’s in the birding world and devotes a full chapter to each raptor likely to be seen at a North American hawk watch site. In addition to key field marks, the book focuses on flight patterns, behaviors and “gizz” (gestalt impressions) to aid in identification.
Several of these tricks of the trade finally stuck in my dim brain after reading Hawks in Flight and, at a minimum, I find that my accipiter identification skills have greatly improved. Obviously, this is a fairly specialized book but, for anyone with an interest in hawk watching, it’s highly recommended.