She’s been sitting for a week now, so the eggs should be half way to hatching.
Robins also readily utilize an open platform type nest box.
I’m hoping this one doesn’t attract any passing predators. The Robin nest is in close proximity to a Phoebe nest on a platform showing in the upper left corner of the photo.
I installed this nest platform specifically for the Phoebes in an attempt to keep them from nesting on the porch. Porch nests almost always failed, usually because some unexpected late night visitor spooked the birds from the nest and the young succumbed to exposure overnight. The Phoebes now raise at least one family each year on this platform.
I have been purposely staying away from the nest so as not to leave a scent trail to be followed by hungry mammals. A broken egg on the nearby walking trail was evidence of what had happened and the disturbed nest was clearly visible from a distance.
Those three species are all common here. This is why the turkey lays so many eggs. It only takes a small percentage of successful nests to sustain the population.
Out of a dozen boxes, only one held a Bluebird nest. Since I see several Bluebird pairs around the field, I assume some are nesting in natural cavities.
Twenty-five years ago, it was uncommon to see a nesting pair of Tree Swallows. Bluebirds dominated the boxes at that time.
Wasps will aggressively defend their nest site from intruding birds or photographer’s heads.
This guy tried to sing from occupied boxes, but was driven away by the resident nesting pair every time. I’m not sure if the birds were defending their nest site against an intruder or just being critical of the Meadowlark’s vocalizations.