Rhuagh mentioned there used to be other Dragons and they fled to the south

From: Raymond E. Feist
Date: 20 March 1996

That's a non-plot thread.

When the book was originally written, there was going to be something called "the Dragon lands" to the south on the western shores of Kesh in some mountains." I've changed my mind.

So, assume Rhuargh was speaking metaphorically, as in 'Went where it was warmer.'