Dusty Springfield - The Look of Love 1967

It is fairly easy to distinguish the male swan or COB from the female swan the PEN. The large black fleshy lump at the base of the bill is much larger and more pronounced on the male, this can be called the "berry". The male's tail is also wider and more fanned out, whereas the Pen's comes to a single point. This difference is not so obvious in this photo.