I love water trough pics! I always think of that song "Cool Water", lol. And your pics are as awesome as always! Does your camera have a burst mode on it? I wonder if that would help capture them better, in flight? I have no idea, I'm certainly no photographer.
Mine is a 10 yr old camera that has a burst mode/continous shooting of 5-6 frames per second and IIRC 23 before it has to catch up with processing those frames. I think the newer model of mine can shoot 8 frames and up to 94. It was in the continous shooting on those pics and I was about 80-90 yards from the trough. So any bird moving was in focus for a frame or two then out of focus just as fast. I had my camera set on a 400 ISO and 1/640 for shooting those pics thru a 500mm lens set at F 5.6. If I had gone up on ISO and faster exposure time they would have been a bit more grainy in that lower light I would think. I am still learning how to use my cameras and self taught. So what I do is probably not correct. I use a lot of manual setting since I am trying to capture the clearest and crispest deer photos, not so much on the birds.
Thanks everyone.