Why are bird's beaks usually yellow?

Add more pigmentation and the color will be deeper and/or brighter. Some beaks have other structural biochemicals in them that allow some measure of flexibility or to reinforce certain areas of the beak. Some beaks are a simple, thin sheath over the underlying flesh and bone, while others are quite thick and more like the horn on cattle. read more

There are two birds with a black body and a yellow beak: the common blackbird and the European starling. Some common blackbirds will have different colored beak, often orange as opposed to yellow. European starlings develop white spots on their bodies during the winter before returning to a black, glossy coat the rest of the year. read more