No, not the occasional rogue chipmunk that finds a way in and runs amok. We’re referring to building projects that help wildlife and which you can undertake in the coziness of your heated wood shop, while the snow flies outside.
Some of the most common projects are those which benefit Iowa’s cavity nesting birds. As the name suggests, there are several species of birds that seek out protective cavities in which to raise their young. Some, like woodpeckers, can excavate their own, but most others, from bluebirds to Eastern Screech Owls, must usually find naturally occurring cavities that fit their particular needs. The competition for a cavity is almost always fierce.
One of the best things you can do to help these birds is to leave dead trees standing. These trees, often referred to as snags, rot and hollow out, providing not just nesting cavities but also food for woodpeckers and others who eat the insects that infest the dead wood. Dead trees make some of the best wildlife habitat so if the snag is not a danger, leave it be!
Putting your DIY skills to the test and building and installing nest boxes is another great way to provide more options for a pair of cavity nesters looking to start a family. Some common cavity nesting species that occur in backyards include black-capped chickadees and house wrens in more wooded areas, eastern bluebirds if you have a more open yard and swallows especially if you have a pond or other open water nearby. Some uncommon backyard cavity nesters are the Eastern Screech Owl, a small owl which likes open, wooded habitats and has been known to nest in suburban neighborhoods and American Kestrels, Iowa’s tiniest falcon which likes larger open areas. If you’re in a more rural area, you might try a multi-apartment Purple Martin house or perhaps a wood duck box near a pond.
There is a lot of possibility and diversity. The key is to create a nest box of the right size and especially with the right size entrance hole for the species for which you are trying to provide.
It’s important to get the boxes ready and put up well before the nesting season starts. Lining them with wood shavings or other natural materials the birds can use to cozy the box up is helpful and it’s usually a good idea to clean the box out between years. Finally, providing some predator protection is a good idea, adding some obstacles if on a pole or keeping tree branches trimmed around the box if on a tree. Some recommended resources for information and box plans include:
ISU Wildlife Extension Wood Working
Cornell Laboratory Nest Watch
Want to show off your box building skills? The City of Ames Arts Commission is holding a bird house contest!