When I was a kid, in Wisconsin, the rivers and ponds would freeze up way too soon. The ducks and geese wouldn't give my two wooden decoys a second look, they flew by way too high for my single 12 ga. Being the devil I am, I took a 5 gallon pail and a bottle of Tintex laundry blueing, that my mom used on white sheets.
What I did was to chop a hole in the pond to dip some water out, add this deep blue salts to the water, and pour it ON TOP of the ice, creating the illusion of open water. The ducks and geese took a whole new liking to my 2 decoy set, and while it wasn't exactly Field andStream, I shot a number of ducks and geese slidng to a stop on my "pond".