Hehe, I like your title, but your photo is only 25% duck, sorry, just had to point that out, though it doesn't matter in any way, I'm just obsessive-compulsive. The focus is a bit soft for me. I like the flow between frames. The desat of the centre frame I think adds overall interest.
The shot of the mallard is great. The goose (?) on the right seems to be a little out of focus. I don't think the B&W shot in the middle does much for the composition. Next to the green of the mallard's head, they seem sort of blah.
The pics are fine individually, but 2 colors and a bw doesn't look too good - at least not here - and the border is uneven and the color would be better black. Any color other than black or white for borders is hard to get away with, but if you do pick a different color, it should come from the palette of one of the images or at least compliment the colors. Hope this helps.