Swans

Swans Crossing black swans tundra swans whooper swans trumpeter swans mute swans black-necked swans whistling swans Bewick's swans New Zealand swans coscoroba swans trumpeter swan [鸟类]号手天鹅 mute swan n. 疣鼻天鹅 black swan [鸟类]黑天鹅(Cygnus atratus,产于澳洲); 稀世之珍，稀有之物，珍品 Bewick's swan 【鸟类】比尤克斯天鹅(Cygnus columbianus bewickii)