Lighting: unique/quiet/moody...I like it. Exposure work is good too.
Composition: Nice, but just a bit too tight I think, particularly for these two large bodied waterfowl. I do enjoy the subject positioning and placement in the frame. Would just like to see a looser presentation.
Sharpness: Perfect.
I'm really liking the mood you portrayed in this image. Great colour to the water, and I love the end-of-day feel. Yes, I too could see a bit more room and I do wish the larger stalk in front of the back was not there.