I used wood shavings this year instead of straw, and that seemed to do the trick.
Brettski,
Have you done any maintenance on the wood duck boxes? Just asking since they should be cleaned out ever year and have fresh bedding added. I good job to due in the winter. I have wood duck boxes on our property in Northern Wisconsin for the last 25 years. I have woodies in most boxes ever year. My dad was at the property the first weekend in Feb. and cleaned out all eight of them.
I have a lot of wood ducks around my farm in Illinois and put in some wood duck boxes last fall on the new pond. I have mixed emotions now since most likely I have to drain the pond to fix a leak. I kind of hope the woodies don't use the boxes this year but doubt it since I see many pairs on my propert looking for nesting place from now though turkey season.