I knew something was wrong. These bluebirds just weren't behaving normally. It had been long enough for the second brood to leave the nest. I clean the house out after every brood, because it is usually a mess all over the insides. Would draw flies. Small insects crawling in the bottom, possibly lice or mites, and trash from pin feathers. As it turned out I need not have bothered.
The box was clean. The nest was tall. I removed it with a square trowel. Buried about halfway down were 5 unhatched eggs.

They had all been viable up to the same stage of development. Something must have happened suddenly about a week to 10 days after incubation started. The weather was perfect throughout. I'm guessing something happened to the female.
Put the top half of the nest back the way it was. Two adult bluebirds came back almost immediately and checked out the house. They may decide to abandon it now. We'll find out soon. I do think this is a new female. She is smaller and more brightly colored. I swear I saw another female just 2 days earlier. They are able to fluff up their feathers and look completely different at times.
Meanwhile back at the ranch, the Eastern Phoebes have 4 eggs in their nest above the outdoor light fixture on the porch. Phoebe perched on the mailbox chirping away at me while I took this picture Sunday.
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