#tundra_swan__Cygnus_columbianus  swan that nests in tundra regions of the New and Old Worlds
  supertype:  swan  stately heavy-bodied aquatic bird with very long neck and usually white plumage as adult
  member of:  genus_Cygnus
  subtype:  whistling_swan__whistlingswan__cygnuscolumbianuscolumbianu  North American subspecies of tundra swan having a soft whistling note
  subtype:  Bewick's_swan__Cygnus_columbianus_bewickii  Eurasian subspecies of tundra swan; smaller than the whooper

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