Broadly speaking, yes, it's the same species, so it would share many similar features with cod, like the way in which they reproduce, as an example. It is obviously recognized as a separate stock with differing life history traits, like how fast they grow, when they mature and so on. They're similar, but somewhat different.
One thing is that there has been some mixing in the past. We know that northern cod, for instance, from time to time, do in fact travel and intermingle to an extent with fish in the northern part of the gulf. They're separate, different, with some interchange from time to time.