That spot you are in will produce birds on a decent southerly. We used to shoot there most evenings regardless of the weather and would pick up a duck or two every time. There are some nice swampy patches over closer to the willows too, which shoot well. The ducks tend to trade up and down the river there and you'll have a better chance of sucking them in. If the weathers calm they'll come in real late. You need to start working your caller on ducks even seen at long distances.
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