If you live anywhere within the continental United States, chances are very good that you have house sparrows. These non-descript brown birds make their homes just about everywhere that we choose to make our homes, from city condos to country escapes, and all the suburbs and small towns in between. They are among the three most common birds in the country.
Despite their abundance, house sparrows are not native to the United States. The birds were deliberately introduced to North America several times in the mid-1800s, and haven’t looked back since.
I wish they would.
The trouble with house sparrows isn’t really their abundance. Nor is it their non-native status. No. The trouble with house sparrows is more basic — these birds are bullies.
House sparrows will readily chase native bluebirds and other cavity nesters from their homes. They will destroy the eggs of other birds, murder their chicks, and even attack, injure, and sometimes kill adult birds they find and trap in their nests.
As I said: bullies.
Now, some people may not mind. For someone who has never watched the cycle of courting, nest-building, and fledging, a nesting pair of house sparrows may even seem a welcome sight. If you are one of those people, I hope you’ll consider taking a different stance this coming spring. By discouraging house sparrows, you give native bluebirds, chickadees, titmice, and more a fighting chance.
Easy house sparrow deterrent
There are many ways to discourage house sparrows. Some people trap the birds. Others destroy their nests. I prefer to prevent their nesting in the first place. This requires a bit of time and awareness, but I feel that’s time well spent. Last year, for example, the nest boxes in and around the Outlaw Garden fledged two families of bluebirds, one family of chickadees, and one family of titmice. That’s some pretty great motivation!
My favorite way of discouraging house sparrows requires little more than a few thumb tacks or nails, scissors, a hammer, and some fishing line. Once you have your supplies gathered, it takes no more than a minute or two to protect each nest box.
What you’ll need
- thumbtacks with raised stem, or small nails / brads (about 8 per birdhouse)
- fishing line
What to do
Grab your supplies and head outside to your birdhouse(s). Using your hammer, gently pound four tacks or nails into the four corners of the roof. Attach two tacks or nails to the front of the roof, more-or-less directly above the bottom of the box. Finally, attach two tacks or nails to the bottom front corners of the box.
(Alternatively, use just two nails/tacks at the top front of the box. In the photos below, you’ll see this is what I’ve done.)
To begin, tie your fishing line to one of the tacks or nails on the roof. Pull it taut, and wrap it around the other nails/tacks both side-to-side, top-to-bottom and diagonally. You want the line to be approximately one-inch about the surface of the box. Once done, you should have created a square and an X out of the fishing line. Tie it off and cut off the excess.
Next, tie your fishing line to one of the four nails/tacks on the front of the box. Pull the line taut, and wrap it around every other nail/tack on the front until you have created a square of fishing line around the front of the entire box. Do not run diagonal lines. Tie off the line and cut off the excess.
Test the line with your fingers. It should be fairly taut.
That’s it. Done.
Why it works
No one really knows, but this little trick works very well (not 100% of the time, but close to it). House sparrows are spooked by the line, but it doesn’t seem to bother our native nesters, such as bluebirds, chickadees, or titmice. Perhaps house sparrows have worse eyesight, since they mostly eat seed. Maybe they think the fishing line is a spider web. Whatever the reason, it works.
The fishing line on the front of the box prevents house sparrows from landing and entering the box (most of the time). And, the fishing line on the top of the box spooks the males, who usually perch on top of boxes they’ve claimed.
Variations and considerations
Some recommend hanging loose line from the eaves of the box, and weighing them down with fishing weights. I do not do this because I worry about the risk of an adult bird becoming entangled in the line and/or pulling the line into the box with them. I just feel safer using line that is tied down and taut.
This deterrent works most of the time, but you may still experience trouble with some boxes. If house sparrows persist, consider adding more line, perhaps on longer nails so that the line is elevated higher above the box’s surface. Or, perhaps simply relocate the box.
Fishing line will degrade over time in the sunlight, and may eventually break or loosen from the tacks or nails. I recommend checking the condition of the line at least once a month, and replacing any line or tacks that look compromised. I generally remove the line entirely for the winter months, and replace it with fresh line in February or March, when birds start exploring potential nest sites.
Fishing line can entangle birds and other wildlife. When using this, please ensure that you remove all loose line from your yard or garden.
And that’s it!
If you have any additional suggestions for protecting bird houses from house sparrows, please share your tips in the comments section below.