If Great-horned Owl, then most likely it is hunting between dusk and dawn. The owls are very fluffy, but not even as heavy as my 4.5 lb game hens. The are strong, especially those feet and you do not want one biting you. I free-range chickens during day without concern about owl issues during this time of year. During winter when overcast is when daytime can be more risky. Hawks and crows are your friend on this as they will go out of their way to harass an owl during the day. Keep free-ranging during day but make certain they get to roost and shut them up by dark. Read the links I provided as they provide some accounts concerning how the owl operate during twilight. Currently I invest a lot of effort training a group of young chickens in orchard that are to not roost in trees, rather they need to go to pens that I shut up at dusk. The owl here clearly watches chickens and me as nighttime approaches. I call it Butt Munch.