Last night between 11:00pm and 6am we lost 2 mallard ducks and 3 chickens, 2 silkies and a large white cochan. The cochan was plum gone but had a lot of feathers pulled. The other birds were only decapitated with the heads missing. We have a large, over an acre, with a 6 foot block wall all the way around. There are tracks, dog or coyote about 4 foot off the ground going up the wall and a couple of white feathers on top of the wall. Nothing but desert behind us and I have never seen a stray dog. We have a pair of resident Great Horned Owls that I'm sure accounted for the headless birds but does it seem likely that a coyote and Owl would both attack the same night and would the large owl be capable of carrying off the big hen.