OK Just lost one of my Peking ducks...5 now 4, the one was dead with a breast area wound, looked more traumatized (than tore up, but the slight breast tear was there) but it was dead. Raccoon? Weasel ? 
Another of the 4 one has a small breast wound appears to be more or less OK, the wound is not bleeding anymore....she is moving about and was swimming in the pond after the attack when I went out into the dark as I was hearing the noise of the hen duck. Should of brought the 20 gauge!
All of this at night in a pouring down rain storm, lucky the windows were cracked open.
The stupid part is that we got home late, didn't get the ducks in the pen, and the rain (again) came pouring down.
I have them in a combination chicken wire/ enamel fence that I guess now needs to be reinforced even though the attack was when they were down near the pond at night in the pouring rain.
Thanks for listening....by the way they are stupid ducks since they were adopted from the SPCA, and as far as I figure they never seen open water till yesterday, they were completely scared of the pond all last week till yesterday my wife & I "pushed" them in just to the edge is far as they would go reluctantly and I waded in and splashed water with my hand making bathing splashing sounds.
So I figure that at least this effort from yesterday might of saved two of them, the other 2 were still running around near the edge and wouldn't go in.
Thanks
Jim Brown
Lockport NY area