Duncraft’s Guide to Bird Houses
Before You Buy a Bird House
When you decide to buy a bird house be aware that there are many designs being sold that are unsuitable for the birds. These houses may not attract any birds or the types of birds you wish, or they may actually be harmful.
Many are very cute and look like little decorated houses. There is nothing wrong with these, but they are often more appropriate as indoor decoration than as good safe homes for wild birds.
Below is a checklist of the nine most important features of a good working bird house. Before you put a house out for wild birds, be sure it has these features. If it is decorative and still has these features, then it is fine to put it out.
Nine Features of a Good Bird House
1. No Perch
Tree holes in the wild have no perches, so the birds that use nest boxes do not need them. They can be a disadvantage in that they may attract House Sparrows, an invasive species that often takes over nests from our native hole-nesting birds.
2. Entrance Hole Size
Most of our common hole-nesting birds can use an entrance hole 1-1/2 inches in diameter. This size also keeps out Starlings, another invasive species that takes over nest boxes from native species.
3. Floor Dimensions
The inside dimensions of the box are important and should be at least 4 inches by 4 inches so that there is room for the young to develop.
4. Box Height
The distance from the bottom of the entrance hole to the floor of the box should be at least 5 inches. This keeps the developing young well down in the box and away from predators that might approach the entrance hole.
5. Be Able to Open
You must be able to open the box, either on the side, front, or top. This helps in two ways: to monitor the progress and health of the young, and to clean out the box at the end of the season.
There should be holes or slits at the top of the box sides or along the top of the front of the box to let hot air out when the sun beats down on the box in summer.
7. Drainage Holes
The bottom of the box needs to have holes or cut off corners to allow any water to drain out of the box.
8. A Way to Attach the Box
Check to see if there is some way that you can attach the box to a pole, such as holes or a bracket.
9. Roof Overhang
The roof should overhang the entrance hole by 1 to 2 inches. This both shades the entrance hole and keeps the rain out.