Keep House Sparrow Nests out of Bluebird Boxes

Stop House Sparrows From Using Bluebird Houses

“What should I do to keep house sparrows from tormenting wrens and bluebirds? Should I take the birdhouses down?” asks Ruth Armstrong of Niles, Michigan.

Many people love to attract nesting bluebirds. Providing bluebird houses is a very common practice which has significantly helped this species. Nest sites are hard to come by and the boxes that people provide are critical nesting sites.

Learn how to build a DIY bluebird house.

Courtesy Vicki Fotheringham

If you install nest boxes on your property, chances are you’ll attract house sparrows. The male house sparrow has a gray and rusty crown with pale cheeks and a black bib. These non-native cavity nesters wreak havoc on native species.

House sparrows were introduced from Europe to New York in 1852 and have thrived in our environment. The species is common throughout most of North America, although its numbers have declined both here and abroad. They are fierce competitors and are more aggressive overall than our bluebirds. This leads to them out competing bluebirds for nesting sites and often killing them.

Is that a tree swallow in my bluebird house?

Remove House Sparrow Nests to Help Bluebirds Win the Battle

Courtesy Ralph Kiertianis

Keeping house sparrows out of nest boxes is part of being a responsible bird landlord. There are several ways to discourage them from using nest boxes, ranging from boxes specifically designed to dissuade sparrows to traps to eliminate them.

Monitor nest boxes every day. If you see evidence of house sparrows, discard their materials. Bluebirds make nests of fine grasses, woven together in a tidy cup. House sparrow nests are more loosely formed, messy and include scraps of debris. House sparrows are not native or protected by law, so it’s legal to remove their nests to protect native birds.

If you don’t have time to tend the box regularly, it’s best to plug the entrance hole until the sparrows lose interest, or take the box down. Better to have no box at all than to allow the sparrows to potentially harm the bluebirds.

We encourage you to visit the North American Bluebird Society’s website for more information, nabluebirdsociety.org.

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Keep House Sparrows Away From Bird Feeders

Courtesy Barbara Bowers

“What seed can I serve to cardinals and finches that sparrows won’t eat? When I fill my feeders, sparrows take over and scare other birds away,” asks Roger Schuette of Staunton, Illinois.

Unfortunately, house sparrows eat practically anything. To discourage these bully birds from gobbling up all the food at your feeders, try eliminating some of their favorites, such as cracked corn and millet. They prefer to feed on the ground or on more open feeders and are somewhat less adept at clinging than other birds.

Check out our picks for the best bluebird feeders.

Courtesy ODell/Birds & Blooms

You can discourage them a little and lure finches by putting out Nyjer (thistle) seed in a sock feeder. A tube feeder with very short perches may also be hard for house sparrows to use, while it attracts goldfinches, pine siskins and other small finches. For cardinals, offer sunflower seeds or safflower seeds in a raised feeder, and avoid using inexpensive seed mixes. You’ll probably still have house sparrows, but can possibly keep them from taking over.

Next, learn how to get rid of blackbirds and grackles at feeders.