I was just about to move on when I saw a drake riding the swift current from the north, and then I realized his mate was just underneath the bridge.
This is the only shot of the female that I was able to get. Great camouflage, eh? She was so close and apparently too close for another male's liking. He shot out of nowhere and practically landed on her tail! She and her mate took to the sky and several times they tried to land in the same general area, but this male was not going to have any of that! It was absolutely thrilling as they flew over me :-) Maybe I'll have better luck next time. This is her mate below. I was able to get three pictures of him before the second male came back around. I didn't know ducks were that territorial.