Garden Variety: Build a home for feathered friends
Birdhouses are a suitable source of shelter for some bird species to build their nests and raise their young. Building a birdhouse is a fun, simple woodworking project for children and adults, especially as spring approaches. Start with a kit or a plan, find a suitable location, and install the birdhouse by late February to early March to ensure birds find it before spring nesting begins in northeast Kansas.
Birdhouse kits are usually available in craft/hobby stores, some toy stores, garden centers and home improvement stores that sell birding supplies. Birdhouse plans are available from many sources online and are sometimes printed in birding and gardening magazines.
When selecting a kit or plan, the most important thing is to choose something appropriate for the skill level of the builder. Often, simple birdhouses are more effective than elaborate ones. Especially if you’re working with a child, find something they can mostly complete on their own.
The next thing to look for in a birdhouse kit or plan is what species it is most likely to attract. For example, bluebird houses (and kits and plans) are usually labelled and sold as such. They are distinct rectangular structures with a slanted top. They are also one of the easiest birdhouses to build.
Other small, wooden birdhouses are likely to attract house wrens, black-capped chickadees, tree swallows and other species. Look for birdhouses labelled for these or which say they will attract general cavity-nesting birds. Keep in mind that some common backyard birds such as cardinals, orioles and finches do not typically use birdhouses.
Gather materials and prepare to modify kits if necessary. For cavity-nesting birds, wood is the best material for birdhouses. Leave wood unpainted and unfinished, or use only natural tones to paint. Install a hinge in the roof of a kit birdhouse if it lacks one so that the house can easily be cleaned after nesting season is over. The entrance hole size on a kit birdhouse may also need altering.
For bluebird houses, entrance holes should be 1 1/2 inches in diameter. For house wrens, entrance holes should be 1 1/8 inches in diameter. For the other mentioned species, entrance holes should be 1 1/4 inches in diameter. These may seem like minute differences, but they are big differences to birds.
If the entrance hole in a kit birdhouse is too large, cut an appropriately sized hole in a thin piece of wood and place it over the original hole to reduce the size of the opening.
If the floor of the birdhouse lacks drainage holes, drill small holes near each corner. You may also wish to add ventilation holes near the top of the house under the eaves.
Perching ledges and pegs are unnecessary. If the kit comes with one or the plan includes it, leave it out. These perches provide a place for predators to land. Even if the hole is too small for them to enter, they may reach inside and grab or harm the nesting birds.
Bluebirds houses should be placed 4 to 8 feet above ground in an open area and are best placed on posts that are set in the ground. The entrance hole should face east if possible, facing the open area. Houses for wrens, chickadees, tree swallows and other species should be 5 to 10 feet above ground and face away from prevailing winds. These houses can be mounted on posts or attached to a structure or tree.
Purple martins are another bird species that nest in houses in this area but are unique in that they prefer large apartment-style houses or gourds mounted on tall posts. If martins are the preferred species to attract, build or purchase a house especially suited to their needs and place in large open areas away from trees.
One problem with the use of nesting boxes is that they may be taken over by undesirable species such as house sparrows. House sparrows are not native to this area. They are considered problematic because they compete with native species for food and nesting sites and reproduce more quickly. If they are observed nesting in birdhouses, remove the nests to discourage them.
— Jennifer Smith is a former horticulture extension agent for K-State Research and Extension and horticulturist for Lawrence Parks and Recreation.