The birdhouse was something the wife purchased several years back. We hung it next to the tool shed in the backyard, and for several years nothing happened. Oh well, we figured it would just be for decoration and let it go. Then, earlier this Spring I decided that the hole was perhaps too small and so I enlarged it in the hope that it would provide entry for a small nesting bird.
Soon after I noticed that a pair of Oak Titmice were entering the birdhouse, with mouthful of grubs. I figured they must be setting up a nest and so I kept monitoring them.
3. Backyard Bully #1. A resident Scrub Jay would harass the pair of Titmice and attack the birdhouse every time the Titmice approached the nest box, but it could not gain entry because the hole was small. But it could look inside and that was enough to stress out the nesting parents.(This is a digiscoped photo taken from my bedroom window) http://farm8.static.flickr.com/7256/6946512980_6ffdb9d2dd_c.jpg
5. The fix. I decided to check out our local Wild Birds Unlimited store to see what was available to protect the opening. I found this plastic attachment. Now the Scrub Jay is unable to get a toehold and the long tube extension prevents it from being to look inside the box. Discouraged, it no longer tries to get near the box. http://farm8.static.flickr.com/7221/7162957084_54ce317804_c.jpg
6. Twittering and cheeping inside the box. There must be nestlings inside. And the frequency of the parent birds comings and goings (mouthful of worms and removing excreted pellets) tells me that all is going well. Unfortunately I could not be monitoring the nest box full time so the birds fledged and I missed a golden opportunity to photograph them. The Titmice have frequently returned to the backyard, as if to say, "thanks for protecting us." http://farm9.static.flickr.com/8008/7476729206_354395faff_c.jpg
Great shots, great story, and great solution. Sometimes we think it is a good idea to have a perch on a nesting box, but often it only helps predators.
The nesting boxes up here for Purple Martin have wire mesh above the hole to stop raptors, and the entrance is a narrow vertical slot that the PM's will squeeze into, but Starlings won't.