I put my wood duck houses on 2" steel pipe about five ft long, monted to a stump out in the water, I havent had any success at attracting ducks , although I have some that reproduce somewhere around the pond, there is no way a coon can climb a steel pipe is there? the boxes are about 6 to 7" above the water, 5' of pipe screwed down to a stump that sticks about 2 ft out of the water.

All the really good ideas I've ever had came to me while I was milking a cow.