Hi Emily
We have both chickens & turkeys that free-range together during the day, but the chucks go into their house of a night & the turkeys roost in & about the decrepid outbuildings surrounding the yard.
I'm not 100% sure what Blackhead is, though I have heard it mentioned a few times, but we don't seem to have had an occurrence of it (
).
Just a few words of advice - our turkeys don't like being shut-in for the night & would much rather perch on the landrover & sh*te all over it
Also, I would avoid getting the white "commercial" breed, as they do not do well outside - Norfolk, Bourbon or Crollwitzer would be more likely to thrive.