"Strange story" - no pictures. My FIL thought I needed some tame white ducks. So, loooong ago, he brought four and turned them loose on my lake. They did look nice - paddling around out there. They were big, they were snow white, they quacked a lot.
Then the problem started. Noticed they were making several trip a day into the cove where the cliff swallows alway nested. It's about 200 yards down the lake, on our side. So I walked down to see what was going on. Those dirty birds were knocking down the swallow nests, off the walls of the cliff, and eating the baby swallows. They would flap hard and could get six to eight feet high on the cliffs to get at the mud nests.
I KNOW the coyotes must have enjoyed "white duck" for breakfast. I told my FIL that they joined up with some wild ducks and flew south.