Three years ago, I bought a nest box and placed it on a tree near our garage. It was a nest box intended for woodpeckers and my hope was that a woodpecker would use it. Despite having plenty of woodpeckers frequenting our yard every day, they didn’t use the nest box. Instead a pair of White-breasted Nuthatches (Sitta carolinensis) took up residence in the nest box and raised a clutch of chicks.
Inspired by that family of nuthatches, I bought another nest box and placed it on a tree outside of our dining room. I was hopeful we would watch nuthatches raise a family while we enjoyed our dinner. A pair took up residence in the nest box and laid a clutch of four eggs. Unfortunately, a house sparrow (Passer domesticus) killed all the eggs, threw them from the nest box and claiming the box for itself.
When I discovered this, I was livid. Researching house sparrows, I learned they are an invasive species introduced from England and are known for taking over nest boxes and displacing native birds, in particular, blue birds.
I also learned I simply needed to narrow the opening to the nest box. House sparrows don’t tolerate openings that are 1 ¼-inch in diameter whereas native song birds such as White-breasted Nuthatches and Black-capped Chickadees have no issue with an opening that small. To displace the unwelcome occupant, I opened the access panel to the nest box, dumped the contents and tilted it at an angle so that the house sparrow could not build a nest in it. It returned daily with nesting materials but all fell out to the ground. I then purchased the appropriate constrictors and attached them to the two nest boxes I had, preventing the house sparrow from entering.
This year, much to our delight, the nuthatches came back to raise a clutch of four chicks in one of the nest boxes. It was a joy to see the chicks following the adults around from tree to tree, learning how to forage for food.
I have a yearly schedule for the nest boxes. I empty the boxes in the fall on the first of October and fill them with wood shavings every spring on March 1st. Emptying and refilling them annually reduces the parasite load, thus, reducing risk for the birds.
We now have three nest boxes, this year one was occupied a Black-capped Chickadee family and another was used by a nuthatch family. The third was too close to another box, so, it remained unoccupied. I moved it further away this fall, I hope it will to be occupied next summer. If all three boxes are occupied next year, I’ll buy another nest box and place it in the other corner of our yard. With luck, in a year or two, we’ll have four families of song birds living in our yard.