What has attacked my chicken?

[Prudle]

Hello, I have an orchard, roughly 700m2. I have 2 geese, 10 ducks, 2 roosters and 10 chickens (9 now). I have 5 man made shelters for them. We had Isa brown who would greet us at the gate, she wasnt there when I did my count. I thought she was exploring. Last night, when I locked the chooks up and did my count, she was missing. This morning I went to open the coops and I found her 8m from the gate near the fenceline. She was missing her head, intestines strewn to the side, all breast meat missing some feathers detached from body. We have a land-predator proof fence - mesh net dug 400mm in the ground, predator lights, hot wire. No foxes..so far, my dogs run and protect the flock at the first sound of a fox..so do I. Ducks don't use their duck coops. No ducks missing. We noticed two eagles flying around but usually myself, my kids or the dogs scare them in our day to day. My question, what predator eats the meat and head from chook, disembowels them and drops them (seemingly). I couldn't get a photo and when I picked her up she was stiff, no smell. Located near Central Coast, NSW, Australia.

 

[sourland]

To me it sounds like the work of an aerial predator.