The Black Swan is native to Australia. It is a popular ornamental waterfowl in many countries and some feral communities exist in the UK and elsewhere.
It is fully black with white flight feathers (see below) and a bright red bill with a white bar near the tip.
Like other swans, Black Swans pair for life.
Your slip's showing.
Black Swan head showing red bill with white band and white/pink tip.
Juvenile
Black Swans with Mute Swans on River Thames.