My unlucky bluebird box did it again. Our near fledgling bluebirds were fine two days ago, but all were found recently dead this afternoon in the box. I saw an adult bluebird catching food this morning. Apparently, feces had not been removed for quite a while. Bad parenting?
I have no idea what happened.
I removed the birds, nesting material and bleached the insides. Left the doors open to get plenty of sun and will close it up hoping for another try. My other box has nesting material but no eggs.