Well, I guess I stepped in this one a little bit... My old college Ichthyology Professor (and I thought the texts at the time) called Montana grayling a different subspecies. The link provided does not open for me. In the old days they did not use the term "arctic grayling" but rather Montana grayling... So I assumed they were using non-native stock. Which they are too a lesser degree than I had thought it appears.