We have a lot of that over the Molalla River, Eagles, Ospreys, Kingfishers. doesn't seem to matter what time of year, if those birds are flying over the river (they zig zag back and forth) they are most probably looking for fish.
Then, when our intended prey sees them, all the fish disapear into as deep a cover as they can find.
Ho Hum.. nature in action, but thats why we are out on the water..