The Mail Bird is a character who appears in "One Last Job," where he delivers a video to Jake about Jake Jr. getting kidnapped. He becomes angry with Jake when he comments that lady birds are not attractive.
He looks like a regular bird with white feathers. He has a long tail, and his beak matches his body color. He has a red ring around his neck and a mailman hat on his head.
Hey! Don't you be talking trash! Our ladies are beautiful on the inside, you creep.
Special delivery for Jake the Dog.