For the Birds: Build a Nest Box -- or put one up

Bewick's Wren with moth by Craig Kerns

By Christine Southwick

March is just around the corner which means that birds are pairing together, and some are starting to build their nests. Indeed, many female Anna’s hummingbirds are already on nests, and today I was treated to the joy of watching a pair of Bewick’s Wrens going in and out of a nest box, adding sticks and leaves to the nest.

Black-capped Chickadees have been checking out a nest box which hangs from a cherry tree branch. Last year Chestnut-backed Chickadees claimed this box in late March, so it is anybody’s guess who the new owners will be.

Red-breasted Nuthatch with bug by Craig Kerns

Cavity nesters like chickadees, Downy and Hairy woodpeckers, plus Northern Flickers will use nest boxes since suitable trees are often cut down.

Various owls will also use nest boxes, but these need to be over 12 feet up on a branched tree and require some heavy lifting.

Pacific Wrens, Song Sparrows, Spotted Towhees, and Dark-eyed Juncos are also pairing up. These birds build their nests on or near the ground and do not use nest boxes.

Bewick's Wren feeding young in nest box by Greg Pluth

If you want to buy a nest box, buy one with a side that can swing out so that you can clean it after the season without having to take it down if you have it in an ideal location. Make sure that the hole is 1 1/8” round if you are welcoming chickadees and/or wrens — too large will allow House Sparrows to take over the box.

Several stores sell nest boxes. If you want the widest selection for each of the several local nesting species, then the place to go is Wild Birds Unlimited in Lake Forest Park Town Center. They also sell kits to build.

If you are looking for a home-centered math and hands-on project during the pandemic, then you could build your own.

Cedar boards 51/2” wide are perfect for building nest boxes in this area. Pine will also work but a box made out of soft pine will only last a year or two. 

Do not paint nor stain the wood. Rougher boards are better, especially on the inside of the box so that the nestlings can climb out when they are ready. Older, seasoned wood is best, but new wood will work if you hang the boxes soon, so that they have time to season for a while.

Basic Songbird nest box plans

The Washington Department of Fish and Wildlife has links to how to build bird boxes (commonly called bird houses).

• https://wdfw.wa.gov/species-habitats/living/woodworking-projects
• https://wdfw.wa.gov/sites/default/files/2019-11/basic_songbird_nestbox.pdf