- The holes must be large enough to start with- they cannot enlarge them.
- There must be soft material inside already- they won't carry in materials to make the nest.
- It must be close to water to increase the ducklings' chances of survival.
- Many wood duck nest cavities were originally made by Pileated Woodpeckers. Unfortunately, they have honey bees, squirrels and other wildlife for competition.
Not only does our backyard (technically the conservation land behind our house) have wood duck boxes, it also has some very active woodpeckers. I just noticed these holes during our walk back there last weekend. I wonder what kind of woodpecker made them.
I also found some very helpful resources on Bluebirds Across Nebraska- a website devoted entirely to cavity-nesting birds. The Wood Duck Basics article provides tips for placement, building plans, and advice about predators.
We don't have any plans to build wood duck boxes since there are already at least that we've seen back there. Here's information I found about the boxes, taken from a Natural Resources Trust of Bridgewater planning document from 2002:
Wood Duck Box
Nesting boxes will provide nesting sites for wood ducks ( Aix sponsa) until more tree snags are available as the forest matures.These boxes should be mounted no closer than 600 feet to each other at a height of sixteen feet, on black locust posts in shallow water, or close to the water so that the ducklings can quickly reach the relative safety of the water when they first leave their nest. The progress of baby wood ducks should be monitored; if more than 75% of the ducklings are disappearing, it is probably due to the abundance of snapping turtles (Chelydra s. serpentina). This should be ascertained and if so, either the wood duck boxes should be removed or the number of snapping turtles reduced. Construction details are in the CSLD design plans.