How big are the ducks and other birds that have been killed? (As in pounds) I did a little research on Ohio owls, the largest is the great horned owl. (Besides the snowy owl, which is very rare in Ohio) They are about 2 feet tall on average, and the females, which are bigger than the males...weigh around 3.1 pounds. Acording to wikipedia. It also mentions that the reagurlary feed on birds, such as ducks, chickens, and even small pets like cats and dogs. It also says this, but I'm not sure if it's still snowing or freezing there. "In northern regions, where larger prey that cannot be eaten quickly are most prevalent, they may let uneaten food freeze and then thaw it out later using their own body heat." If there's still snow on the ground, then this would be your culprit. If there isn't...I'd keep looking for clues.