Cantus Arcticus is an orchestral composition written by Finnish composer Einojuhani Rautavaara in 1972. It is probably his best-known work. Subtitled Concerto for Birds and Orchestra, it incorporates tape recordings of birdsong recorded near the Arctic Circle and on the bogs of Liminka in northern Finland. The work is in three movements: The bog opens with a flute duet, after which the other woodwinds join in, followed by the birds. The second movement, Melancholy, features a slowed-down recording of the song of the shore lark. The final movement, Swans migrating, takes the form of a long crescendo for orchestra, with the sounds of whooper swans. At the end both birdsong and orchestra fade, as if into the distance.