Buzzard Threat?

A magnificent Buzzard was perched on a branch which overhangs the chook run. The hens were cowering under bushes below. When I arrived the Buzzard gave out a "cry" and flew off. So my question is. Are Buzzards a threat to fowl? I have never heard of fowl being targeted by them but I have flown them against Rabbits, which take some handling by the bird. Hens would not be as much a problem to them. Once the Buzzard had flown the hens returned to doing what they do. I would guess that Hens would be far more aware of whats going on around them than rabbits, but I dont know. Any ideas?

Funny enough, I saw a Buzzard here a few days ago - they're rare birds down here. This one was being mobbed by a gang of grey crows.  I would imagine that a Buzzard would have no problem snatching an unaware hen, but hens are rarely unaware!  I think fowl, particularly if there's a cockerel or two with them (I find cockerels are always first to spot any predator) will be gone under cover before the Buzzard gets a chance.  It's different with Sparrowhawks which, as you know,  arrive out of nowhere like a lightning flash,  relying on surprise.  I'd love to see more Buzzards around here.  Sparrowhawks are ten a penny here and I never lose chickens to them - though they do cause havoc among the Collared Doves!

Buzzards are a success story here I am pleased to say. 14 years ago they were a rare sight but now they are more common than Sparrowhawks. A great sight on a summers day watching them ride the thermals. I would have a hard job shooting one even if it was in my chook run. They do scare easy though, I would just have to get inventive.