Would be cool to have a bird's nest dungeon which would be a very small chance of it appearing every time you raid a bird's nest. There could even be a lot of bird-related loot such as feathers, eggs, and maybe even exclusive items with the signature heart container.
Edit: Dungeon birds would do regular combat with openings instead of instant damage. there could be some that do instant minor damage but I feel that takes away the charm of dungeons. However, that should not be the entire dungeon in my opinion.