Just a quick notification to any Bethesda people who pay attention to these sorts of things (if at all).

Hearthfire made the Hawks revert to their old bugged behavior... Which means they no longer re-spawn at all (if they were recently killed before downloading Hearthfire, their dead corpses remain and do not respawn, and formerly living ones are completely gone).

Just another little tiff to add to the list.
Then again, maybe it's just my game.

Just a heads up.

(P.S.)
It's either Hearthfire if not Dawnguard which did it.