There's a lot to be said for bird netting.
In this case I had to roof the entire breeder pen, after a goshawk destroyed my pile leghorn hens.
The goshawk was a bit too young to eat the hens, so he was just learning the ropes. Still, it was a shock.
But after netting the roof, while it was difficult because of the irregular shape and various internal plants, the goshawks haven't been back.
It's a pity I can't free range, but unfortunately we have so many tall trees that the hawks only have to sit still in the high branches for a while, before they can take their pick of the chooks. Even the big Malay cockerel was terrified and spent days quailing in the pen. I figure it's just not worth the stress to my birds.
It's not only goshawks, either: the other day I saw two white breasted sea eagles doing the fly-by. I'm not sure they'd go for a chicken, but they're certainly big enough!
If only I'd had my camera in hand...