They were still in the nest box, reaching and stretching their necks out with regularity when I had to tear myself away from the swing at 3:00 to get ready for a 4:00 meeting. Though I hoped against hope they would wait till morning, I should have known the stretching and reaching meant they were on the verge of flight---but they had been stretching like that all day, and I was still operating on my morning fledge theory, so I thought it safe to leave. Live and learn.
Just before driving away to the meeting (a few minutes before 4:00), I paused in the driveway for a final looksee. Already then I saw no activity, and chalked it up to the brevity of the observation. But now I'm sure. After four days of vigilance, I missed the moment of fledge by a single hour. It's hard to believe how much anticipation I had built up for seeing my baby blues take their first exhilarating flight, and how much disappointment I now feel that I let them down.
It's another example of the loveliest and most captivating feature of the natural world---that it does what it does regardless of anyone's notice. Here are a few shots on the morning after.