Yes, Cooper's will go after full-grown chickens. They'll chase them
down on foot often. (Peregrines, like all falcons, most often take
their prey in the air.)
A Cooper probably couldn't carry off a large, full-grown chicken, but
they'd eat what they could while on the ground and then leave the
carcass, or most of it.
Immature Goshawk is also a possibility, since they look very much like
immature Cooper's. The white on the tail tip is wider in a Coop (unless
it's badly worn down), but can also be seen in a young Gos. You say a
"band of white," though, which makes me think it more likely was a Cooper.
On 11/23/2012 9:16 AM, Linda Lunna wrote:
> After reading a post from a few days ago and checking Sibley, I am thinking
> the attacking bird that we saw may have been a Cooper's Hawk because it had
> pronounced striping on tail--especially the underside and band of white at
> tip. Estimate the bird to be about the size of a crow.
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