I eventually found a sound clip that would play. The tune is closely related to 'La Fille aux Chansons' / 'Marion s'y promène'- recorded back in the 1970s by Malicorne; my copy went missing long ago, so I don't remember what their source was (if they named one). See http://www.gabrielyacoub.com/fr/disque/titre.php?idTitre=151 for a transcription of that lyric.

There's a whole series of French songs that deal with the same basic story; a girl is lured on board a ship by a captain who has designs upon her. In some forms, she escapes by cunning; in others she comes to a ghastly end. I think this may be one of the latter type.

For some related material here, see thread Trois Navires.