Thanks for the advice Vortex. My boxes went up right around ice out and they are up for the first time with fresh pine shavings in them.

I have one on my fiberglass pond light pole so no way predators can climb it (too smooth). The second one is a little higher about 100' away in a dead tree and I have the tree wrapped below it with a 2' section of stovepipe as a predator guard.

I only have grass between the mounts and the pond edge but the houses are mounted right on the edge of a fairly thick stand of trees.

the last two years a wood duck pair stopped overnight around April 12-13 and then were gone. I was hoping they would stop again, but no joy yet.