Brendon Body is currently a Character Animator at Double Negative but he worked on Legend of the Guardians: The Owls of Ga'Hoole at Animal Logic and contained in his Showreel are some beautiful shots he did from that film. After having an experience like that there is no doubt he knows bird mechanics.
Brendon has a very informative blog and he's created a fantastic read every animator should check out with "Tips and Observations of Bird Flight." To see for yourself, click HERE.
You can check out his Showreel HERE. Really great stuff!