Mute Swan

The Mute Swan is a massive white waterbird with a long neck often held in a graceful S-curve. Adults have an orange bill bordered in black and topped by a prominent black knob, larger in males. Juveniles are grey-brown or white and have duller bills. Despite the name, adults are not silent: they hiss, snort and grunt, while their wings create a rhythmic throbbing in flight (Wikipedia, general species account).

Mute Swans inhabit lakes, slow rivers, estuaries and managed park waters. They feed chiefly on submerged vegetation by dipping the long neck and upending, while also grazing ashore. Pairs defend nesting territories and build large reed-and-plant mounds near water; both parents guard the cygnets. Native to much of temperate Eurasia, the species has also been widely introduced, including records in Japan (Wikipedia, general species account).