You’ve seen them nailed to trees, stuck to the sides of fence posts, and propped up on poles near the edges of ponds. You’ve probably even watched a livestream of what goes on inside them. But do you know how to make one yourself?
We’re talking about nest boxes, those wooden bird houses with holes for front doors. This week is National Nest Box Week, an event created by the British Trust for Ornithology that encourages U.K. residents to put up the bird homes. According to Jeff Baker, head of marketing at the British Trust for Ornithology, the idea for the week started 19 years ago, with an effort called Britain Needs More Holes. That aptly-named initiative was successful in drumming up interest in nest boxes, but BTO wanted to single out a particular week as the ideal time to put up homes for migrating birds.
“NNBW falls on St. Valentine’s Day because it is the time of year when birds in the U.K. start to pair up and prepare for the breeding season,” Baker wrote in an email. “It is also designed around the time to think about putting up a nest box or clearing out old nests from last year.”
Why Birds Need Nest Boxes
Nest boxes are important for birds because, as NNBW’s “Britain Needs More Holes” title suggests, there aren’t enough hollows in dead trees, cracks in old buildings, and other natural cavities to go around. Old trees are often cut down to make way for new tree growth or commercial development, and many old, cracked buildings are renovated.
What Birds Benefit?
A wide range of bird species seek out hollows to build their nests—in the U.K., the list includes large birds like the Tawny Owl and Jackdaw, as well as smaller birds like tits and sparrows. In the U.S., nest boxes can be home to water birds like the Wood Duck and even the Great Blue Heron, as well as titmice, warblers, and wrens.
How Many Nest Boxes Do We Need?
Baker says that, while it’s impossible to count how many nest boxes have been erected since NNBW began, it’s safe to say that the week has inspired thousands of nest box events around the U.K. He doesn’t know of any similar nest box weeks in the United States, but that doesn’t mean bird-lovers on this side of the pond are left in the dark over when to erect their boxes. According to the Cornell Lab of Ornithology, people who live in the southern U.S. should put up nest boxes by February, while those in the North have until mid- to late-March.
Tips for Putting Up Boxes
There’s no one-size-fits-all policy when it comes to nest boxes. Eastern Bluebirds, for instance, will go for boxes that face east towards open land, while Barn Swallows will nest in open boxes that are set up in sheltered areas close to a mud source. The Cornell Lab’s NestWatch program has a handy guide to what kinds of boxes each bird prefers, and also provides downloadable construction plans and data on what nest boxes are needed most from region to region. It also has suggestions on how to keep out invasive species like European Starlings, including limiting the size of the nest box hole or plugging the hole until nesting season begins.
As for first-time nest boxers, Baker has a few tips: buy or make the right box for the species you want to attract and site the box accordingly.
And most importantly, be patient. “Nest boxes are not always occupied in the first year of erection; it can take several years before a nest box is used for the first time,” he says.