I saw a "million" ducks in the river

On the return half of my run tonight, there is a quarter-mile stretch that gives a good view of the Jordan River. Because of light being reflected from the water, I could see the river quite well. I saw many dark objects on the water. The objects were ducks. There must have been two or three hundred of them. They seemed to be swimming against the current just enough to remain stationary relative to the shore. I've seen flocks of birds gather in trees as one large community to spend the night, but this is the first time I've seen large quantities of ducks gather as a community to spend the night. I heard a few quacks here and there, but for the most part, the ducks were quiet.