Peeper

Peepers are bird enemies in Yoshi's Story. They are mostly found at the highest parts of levels. They first appeared in 3-2 The Tall Tower, where they tried to stop Yoshi from reaching Inviso. If a Yoshi were to eat one, it will not heal the Yoshi but instead it will give him an egg to help him along the way. When a Peeper is shot down, a puff a smoke will appear and the Peeper will lose its feathers and fall away. If Yoshi eat a Peeper when they lose their feathers, will completely heal him.]

It is possible that they reappear in Super Smash Bros. Brawl. In the Subspace Emissary, when the player defeats a Ticken, a creature that appears to be a Peeper pops out and flies away.