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Blue-Feathered Swallowing Swallow is a type of bird that tweets and swallows. Hints the name that it's given. Papa Bear is trying to show Baby Bear, Zoe and Elmo how they can get their Bird-Watching Badges. They don't see the bird till the very end.
The swallow appears in the 2008 direct-to-video Sesame Street special Love the Earth!