The swan has a harmonious voice, with which it pours out a sweet song. They can sing so sweetly because of their long curved necks down which their voices travel, making their song more pleasant. In the Hyperborean regions swans are attracted by the sound of a zither or harp and sing along with the bard when one is played. The song a swan sings before it dies is the sweetest of all. Sailors consider the sighting of a swan to be auspicious.

The white feathers of the swan signify deception; just as the white feathers hide the swan's black skin so does man's deception hide a sinful heart. As the swan likes to sing in company so are those who live for their desires and seek out like-minded company.

Hildegard von Bingen says: "À person who is congested should cook its liver and eat it often. It will take the rotten matter from his lungs, and he will be cured. One who ails in his spleen should often cook and eat the lung of the swan, and his spleen will be healed." (Throop translation)

The idea that the swan sings sweetest as it is about to die is the origin of the phrase "swan song", the magnificent final performance of a muscian, poet or artist.