Guest kenny is correct that Andy M. Stewart is the writer of this classic song. I've heard him introduce and sing it. It's listed in Andy M. Stewart's elusive and wonderful songbook http://andymstewart.com/songbook.htm . Kenny, do you know of any movement toward re-publication of the songbook?

Listen here to verify lyrics: http://www.youtube.com/watch?v=iC1ZY8SC4ew
In this recording (from the "Wild and Beautiful" album), kenny, Andy sang "And it's feared she's gone down...".

I can't verify with information from the LP since mine burned up, so it's good Guest kenny has both the LP and the songbook. Andy's website lists the title as "The Fishermen's Song". I understood it to be "The Fisherman's Song".