If a coyote finds a clutch of young pheasants that can't fly yet, it'll get them all.
Same if a bobcat or couple of barn owls find a covey. The cat will stay until none are left according to a warden I talked to.
I know for a fact the barn owls will return every evening until all are gone. Kites and Merlin's and Harriers are probably the worst on them. But Swainsons and even kestrels take their toll.
We have a big broadwing hawk with dark gray mottled under wings that work them over to.
There was a reason many travelled to Kittyhawk years ago to shoot the migrating sharks of the sky.
