Setting up in the middle of a feed field with a slew or pothole can be very tricky. Birds tend to be extra-wary and circle multiple times to check out the full spread.
Because you are hunting a small body of water with no overhead cover, sun direction is the most critical, with wind being a close second. If possible, set blinds to position the sun at your back with a crossing wind.
Concealment under this scenario is paramount. You must be hidden and hidden well, which is why I consider an FA Brand layout blind standard equipment on this setup. The majority of time birds will land in the water and then make their way to the surrounding feed. So, set your decoys to give birds the easiest path into the largest section of the water. They prefer to set up their approach over water on their way to the decoys - think of the water as their runway.
Your traditional pond setup is usually a bit more forgiving and provides a bit more natural cover than most. Birds are conditioned to use the pond as a sanctuary and will have a preferred side or area. You can find this area by scouting, but a good tip is it's usually the flattest, shallower side that provides good visibility to predators. Set your spread on this preferred location.
Run one long strip of decoys out toward the middle of the pond, on the downwind side of the spread. This provides visibility and will pull birds from a distance. Placing the majority of the decoys close to the water's edge will pull birds from the edge of the spread into close shotgun range. When possible, position your hunters with a crossing shot so birds are not looking direct at them during their approach. As always, concealment is a critical piece to this puzzle.
The most critical element when hunting a river with ice and/or snow is visibility. Second most critical is your calling. You must set the spread in a highly visible location with open water. Because of the ice, ducks will fly the river much more than normal in their search for prime open water areas to loaf. You'll treat some aspects of this setup like you would on a pond hunt.
First, run a long string of decoys out toward the main river channel. This will provide maximum visibility to passing birds. Place remaining decoys around water's edge and a few in the open water. Ducks will almost always land in the water, not on the ice. Give the birds a long stretch of open water to make their approach, and don't be afraid to use loud, frequent calling. This will help the birds pinpoint your spread location. Snow covers for your layout blinds are ideal under these conditions. Position at least one hunter so he can cover the main river channel for birds that land outside the decoy spread.
When hunting a cut grain field for geese, concentrate your spread at the highest point in the field - try to find a knoll or rise in elevation. Geese prefer to land in these areas because it gives them a superior vantage of approaching predators. Once they feel comfortable with the area, they will work to lower elevations to feed.
It is best to set your spread so geese are not looking directly at you when they approach. The classic H pattern set at a crossing wind will give the incoming birds a natural-looking spread, while reducing the chance of the birds seeing the hunters. Last Pass Full Body Canada Goose decoys, and low-profile Final Approach blinds fit this job to a "T".
I'll beef-up decoy numbers around the blinds. This will help break up your outlines and provide extra concealment. Utilize the shadows the decoys are casting to help conceal the hunters (blinds). Run slightly fewer decoys parallel to your main body of the spread. This does several things: It will give the birds other areas of focus, rather than where the blinds are. It will displace more area, which gives the illusion of a bigger, more relaxed feeding spread, rather than a tight "busy" looking set. And also, the reduced number of dekes in that area will offer an easy place for the new birds to land.
Lastly, connect the two parallel groups of decoys to complete the H pattern. This should be positioned slightly upwind of the hunters and will provide a natural backstop for approaching birds. Stagger the position of the decoys so that they look natural, avoiding the evenly spaced "toy soldier" look. Keep your spacing and gaps random, like live birds do.