What is the common name of the bird species Cygnus olor?

The common name of the bird species Cygnus olor is the mute swan.

The mute swan is a large waterfowl species in the family Anatidae, which also includes ducks and geese. It is native across much of Europe and parts of Asia, although introduced populations are established in places such as North America, Australasia, and southern Africa. Adults are typically white, with an orange bill bordered in black and a prominent black knob at the bill's base.

The word “mute” does not mean the bird is silent. It refers to the species being less vocal than some other swans. Mute swans communicate with hisses, calls, and wing sounds; their powerful wingbeats can be heard during flight. They are also known for “busking,” a threat display in which the neck curves back and the wings rise.

They are sometimes confused with whooper swans or trumpeter swans. Those species have different bill patterns and vocalizations, while the mute swan’s orange-and-black bill and knob are especially distinctive.