The adult Mute Swan is a large familiar bird, all white with a reddish-orange bill and a long, often arched neck. The Male bird has a large Black facial knob above the bill, the female has a smaller facial knob but it is still a distinctive feature.
Long thick neck
The Juvenile Mute Swan has a Brownish body and a grey bill with Black edging. As the Juvenile gets older it gradually becomes paler, eventually becoming all white by it's second Winter.