War of the Birds (1990)

Fagin is the bad bird of an otherwise idyllic forest. He assaults the nest of two wrens and destroys all their eggs except one that, when hatched, is adopted by an owl (patterned on W. C. Fields). A counter-offensive against Fagin is launched with help enlisted from a seagull named Armstrong, two nice mice and a sparrow. There is romance, too, and a jazzy score goes with this animated ornithology extravaganza.