What eats JUST the head?

[sourland]

Lock them in the coop at night, and provide a covered run for their daytime use.

 

[Jeremymct]

I agree with it being an owl. Last summer I lost a lot of birds to them. I was letting my chickens free range. I found that it always struck between 5am and 10am. So I started keeping them locked in the netted pen until noon before letting them free range and then I didn't have any more problems.