Silverwing (2003)

Long ago, there was a great war between the beasts of the land and the birds of the air. Because the bats shared aspects of both sides, they chose to stay neutral in the conflict. For that, both sides banished the Bats to the night, never to see the Sun again. In the present day, a young undersized Silverwing bat named Shade, in a fling of youthful impulsiveness, dares to violate that law. As a result, the Owls demand he be surrendered to them for punishment and when the colony elder refuses, the Owls destroy the colony's home. In the resulting premature migration, Shade becomes separated on a island where he finds a new friend, a Brightwing bat named Marina. Together, they set about to rejoin Shade's colony, but events are unfolding that threaten his people and perhaps only those young bats can stop it.