If only...the Eurasian Tree Sparrows had not overtaken the first box. The Carolina Chickadees had already put a lot of work into their nest building there. Our modifications to the entrance hole were not made soon enough and the sparrows took over the 'white house'. The chickadees tried, but they're simply not aggressive birds and couldn't hold the nest site. They need an average of 30 days to rear their young. That means 12-15 (average of 13 days) to incubate the eggs and then another 16-19 (average of 17 days) before the young leave the nest. The young might have fledged this week.

By Sunday, 4/13, I was pretty sure the female was laying eggs because she was not leaving the PVC nest box. The male would come in and feed her. Then on Thursday, 4/18, she did leave the box to bathe and preen after laying an egg. The pair flew off together to forage a bit. 

Big mistake, they were not aware that the House Wren had returned to the neighborhood. He pounced on the opportunity to ravage the nest box.

Sometimes, one image says it all.

The chickadees tried for two days to chase him off, to no avail. House Wrens do not tolerate competition in their territory, even of much larger birds. They will destroy eggs, kick out young chicks and sometimes kill adult birds. It's a survival method for them that wreaks havoc with many species of birds like Carolina Chickadees, Eastern Bluebirds, Prothonotary Warblers - all cavity nesters.

The Carolina Chickadees only have one brood a year so this nesting failure is a bitter pill to swallow. Next year, this box will be up and ready early with more hopeful results.