We have a nest with three baby juncos they were barely without feathers. Looks like feathers were just starting so they were still very young. Mom and dad religiously would go back to the nest and feed them. Mom would sit with them at night. One morning when I went outside with my dog there were no birds anywhere and when I checked the nest it was empty. No signs that it was tampered with. I'm guessing while we were at work a squirrel came in and raided the nest. Will the parent birds come back to the nest or will they abandon it never to return?
Washington County Oregon
Thanks for your interest.
It is most likely that the parents will abandon the nest for the year. They may still remain in the area, but it is getting late in the season to begin a new nest. It is not unusual for birds to start a 2nd clutch of eggs if their first is destroyed, but not usually so late in the season.
They may stay in the area and they will probably return next year. But they will most likely build a new nest.
All the best