For those who love bluebirds, the sight of a house sparrow eyeing a bluebird box is both maddening and frightening.
House sparrows are cavity nesters, just like bluebirds, but they are far more aggressive. They are so territorial that they’ll claim multiple boxes and exclude all others from nesting even though they can’t possibly use them all. What’s worse is that male house sparrows will kill adult bluebirds inside the nest box and peck the chicks to death as part of this territorial behavior.
Many are the sad stories of house sparrow attacks and dead baby bluebirds. Beakless Bluebirds and Featherless Penguins by Sister Barbara Ann tells of the success she had in raising two beakless bluebirds who survived an attack thanks to her care. Not everyone has the time or skill to do this.
As bluebird monitors will tell you, there is no real way to exclude house sparrows because they are nearly the same size as bluebirds. The only effective method is to trap every house sparrow and remove it. It is illegal to trap native birds without a permit, but house sparrows are non-native and invasive. They can be trapped and removed.
There are many Internet resources that explain how to do this. Try the Bluebird Society of Pennsylvania and Sialis.org for starters.
Right now is bluebird nesting season. It’s time to trap this house sparrow.
Hey you, House Sparrow! Get away from that box! Don’t you even think of it!
(photo by Bobby Greene)
Thanks for the great resources on attracting bluebirds. Since we all can’t have peregrines in our backyards, we can attract bluebirds!
Like that picture!! They do try their best to usurp bluebird boxes. There are 27 bluebird boxes at Crooked Creek and so far a total of 30 bluebird eggs, 6 little white Chicadee eggs, and only 3 house sparrow eggs. I watched the house sparrows vie for one near the park office but chased them once and noticed the bluebirds hanging around same day so perhaps they managed to get started before the sparrows were successful there as they have 3 eggs in a bluebird box other side of the road. I do think tho’ that the pretty tree swallows are nesting in another box.
I’ve read that tree swallows also create problems for bluebirds (within their overlapping ranges) around nestbox competition.
We have both tree swallows and bluebirds in Albany NY area (of course house sparrows are EVERYWHERE). Is that a problem in W.PA?
Tree swallows will nest in bluebird boxes but they don’t pose a problem if the boxes are erected in pairs. In this arrangement, tree swallows take one box, bluebirds take the other and they happily coexist. Here’s more on how that works:
http://www.treeswallowprojects.com/tresvsbb.html