Generally a birchen chick will have all black down, not always, but if it is a true birchen it should be black. Usually an extended black chick will have the white markings on the face, chest and under side.
Birds that have a black phenotype ( color of the bird) will have a down color that is very similar to a birchen bird. That is if the black bird is extended black at the E locus. If a person introduces certain genes to the offspring of a birchen bird, the offspring can be black. The black offspring will have the same down color as the birchen parent. Skin and scales on shanks and feet should be yellow or white or blue on birchen birds. Extended black birds( self black) will have black shanks and feet. Tim
