It's a long time since I posted on Mudcat - I hope I do it right!
There's a good article on the song Waterwitch on SIMPLY AUSTRALIA. The article by John Low (who happens to be my brother-in-law) is called The WATERWITCH: SOME THOUGHTS ON A TASMANIAN WHALING SONG AND ITS ORIGINS.
Here's the actual url of the article which appears in Issue 3 of the online magazine.
I hope this helps.