Birdhouses are often promoted as one way to attract nesting birds, primarily songbirds, to your property. But did you know that different types of birdhouses will attract different types of birds? Or that not all birds will use birdhouses? Or that some birdhouses can actually be harmful to birds? It is important to choose the right type of birdhouse in order to attract the types of birds we want and to provide safe housing for the birds that use the birdhouse.
The birds that use what we typically think of as a birdhouse are collectively called cavity nesters. A cavity nester is any bird that naturally nests in a hole in a tree. Examples include woodpeckers, chickadees, house wrens, bluebirds, wood ducks, screech owls, and many more. Other birds like phoebes and robins won’t use a traditional birdhouse, but instead may nest on a nesting platform. A nesting platform is simply a platform or floor, usually with some sort of roof but no front and only partial sides if it has sides at all. Other birds like cardinals won’t use any sort of manmade structure.
When choosing a birdhouse, keep it simple. Fancy birdhouses that are painted bright colors, have metal roofs (possibly made from an old license plate), have multiple “apartments” (except for purple martin houses), or have porches and other decorative features may look cute, but aren’t likely to attract many birds other than perhaps house sparrows. A generic wooden birdhouse, without a perch, that is painted a neutral color or allowed to weather naturally is best for the bird. The birdhouse should also have ventilation near the roof, have drainage holes near the bottom in case water gets in it, and should be easy to open up and clean.
The size of the box and the size of the entrance hole are also very important. Larger birds obviously need larger birdhouses, but don’t make the assumption that a smaller bird will just “enjoy” the extra space provided by a birdhouse designed for a larger bird. Smaller birds are attracted to smaller birdhouses. The size of the entrance hole also matters because it needs to be large enough to let your target species in, but small enough that non-native pests like the house sparrow will not be able to enter.
House sparrows are a problem for several reasons. First, house sparrows begin nesting before many of our migrating songbirds arrive which means they can occupy a birdhouse before our native songbirds get a chance to occupy it. Perhaps even worse, if a pair of house sparrows decides they want to nest in a birdhouse that is already occupied by another species of songbird, the house sparrows will drive out or kill the current residents (adults, young, or eggs) in order to take over the birdhouse. They also raise multiple broods each year which can cause their population to grow rapidly, especially in urban and suburban areas.
Choosing birdhouses with smaller entrances is one way to prevent house sparrows from taking over a birdhouse, because they can’t take over if they can’t get in. However, this could also keep out some of the larger native species. As you can see, there are lots of considerations when choosing a birdhouse and different species of birds need different sizes and styles of houses. If you are thinking about putting up a birdhouse, I suggest you take a look at this site provided by the Cornell Lab of Ornithology. It has all kinds of information about different birds that use birdhouses or nesting platforms including plans for building the different nesting structures and where to locate them.
This article was part of Shannon’s original Kentucky Pollinators and Backyard Wildlife blog which evolved into the blog for Backyard Ecology.
Backyard Ecology: Creating Space for Pollinators and Wildlife
Nature isn’t just “out there.” It’s all around us, including right outside our doors. Hi, my name is Shannon Trimboli, and I am the host of Backyard Ecology. I live in southcentral Kentucky and am a wildlife biologist, educator, author, beekeeper, and owner of a nursery specializing in plants for pollinators and wildlife conservation. I started Backyard Ecology as a way to share my love of exploring nature and learning about different plants and animals. I invite you to join me as we ignite our curiosity and natural wonder, explore our yards and communities, and improve our local pollinator and wildlife habitat. Learn more or subscribe to my email list at www.backyardecology.net.