Much like a cornfield lured baseball players in the movie, “Field of Dreams,’’ a birdhouse can be quite attractive to several species of birds. But, unlike the movie, there really isn’t much magic involved — just a few scrap boards and some simple tools.
A female western bluebird delivers a morsel to waiting young inside a birdhouse. Birds have a super-charged metabolism and can consume an incredible number of insect pests in the course of raising a summer brood. Along with maintaining healthy riparian areas, where birds thrive, landowners would do well by attracting birds through the use of artificial nestboxes. Photos/JIM WARD
In general, there’s really two types of birdhouses — the one that resembles a miniature version of a Hilton hotel with multiple compartments and a designer paint job. The other is a no-frills type which is basically a square box with a small entrance hole poked in one side. In truth, birds prefer the more simpler model. The more rustic the better.
Not all birds are attracted to birdhouses. In fact, most species either build a grass or twig nest on a limb, like robins, blackbirds and jays, or nest on the ground like quail, meadowlarks and killdeer. Those species that use birdhouses are referred to as cavity-nesters. It’s really a trick we humans play.Birdhouses simulate a cavity carved into a dead tree by a woodpecker. In nature, the woodpecker, or primary cavity-nester, selects a snag with soft wood and carves out a cavity to rear it’s young. The woodpecker uses this for a year or two and moves on to build another. Then the secondary cavity-nesters move in to use this abandoned home. These birds can’t carve a cavity for themselves, so their very livelihood depends on the woodpecker.
Bluebirds, tree swallows, house wrens, wood ducks, kestrels and several species of small owls seek out these woodpecker homes and can be fooled into thinking your birdhouse is just such a thing. These species are rather common in our area.
Barn owls find shelter in a nestbox. Nextboxes should be put up on the north (shady) side of the building to prevent overheating.
Of course, there are a few things that can be done to make this house more appealing to the particular species you wish to attract. Things like the size of the box and entrance hole, presentation and the type of habitat you erect your box in are important.
Tree swallows, a mosquito’s worst nightmare, are fond of birdhouses. They live throughout our valley and tend to feed near open water.
Bluebirds like boxes, but seem to avoid the valley floor and prefer forest edges, foothills and mountain meadows. These two prefer open areas.
The house wren likes brushier habitat and so does the small owls.
Wood ducks like boxes along wooded streams, marshes and ponds.
Pages could be written on birdhouse specifications and I’m sure The Observer editor won’t skip the sports page in this issue so I can ramble on. The Internet is a good source of information about birdhouse specs and our local wildlife department has handouts for those wishing to build a house (963-2138). In general, the smaller birds need a cavity about the size of a shoe box. Kestrels, wood ducks and the owls should have a larger box similar in size to your computer tower.
In truth, birdhouses are sort of a Band-aid often used as a substitute in place of natural cavities. Wildlife biologists often suggest that the modern world has a severe shortage of snags in our forests, uplands and in our lowlands as well. This shortage has had a profound effect on those species that need them for nesting. Competition for nesting sites by non-native starlings and house sparrows hasn’t helped either.
Cavity-nesters tend to avoid urban settings, but don’t despair if you live in town and want to build a birdhouse for one of these species. Due to their relentless consumption of insect pests and rodents, it shouldn’t be difficult to find a farmer or rancher who’d love to offer a site for your project. And due to these birds’ constant craving for a nest site, your birdhouses are almost guaranteed to attract an occupant.
Rest assured — if you build it they will come.