I'd like to see someone come up with an innocuous variation on that line that makes sense without requiring explanation. I suspect that "starving slaves" is a mangling of the original wording (not that I claim that as a unique insight!), but clearly no one sees what words were being mangled. It's possible that someone just made up the verse off the top of his head and those were the words that bumbled out of his mouth, but even then it seems very awkward and unlikely phraseology.

It's too bad we didn't have another source for the song; I think it was fairly well known at one time, at least in that area of Cape Breton.

After reading some of this thread awhile back, I started singing that line as "TWO starving slaves out on Scatterie", which suggested that suggested meaning a little more strongly, but it's still a pretty weak line ...

Of course, it depends on how you feel about making any kind of alteration in the received text.