Last night around 7pm I went outside and saw something fly from my chicken lot. It was a large bird but I couldn't see much detail without my glasses. There was no commotion coming from the coop and all of my chickens should have been in the coop. I went out this morning and found a chickens head laying in the middle of the lot. Feathers were everywhere but no blood and no signs of the body anywhere. Any ideas of what I could be dealing with?