I observed the first sign of nest building today. Saw Mama sitting on the box with some grass in her beak. She took it in the box and left. Daddy was sitting on the roof, peering at the hole while she was inside. As soon as Mama left, he went inside and carried the grass out. Not sure what this means or if this is serious nest building. Last year they began constructing a nest on 15 March.
Just like last year, the birds became more interested in the box in late February. They would land on it, go in and out and Daddy became more territorial of the space around it. A cold front came in today, but it is clear. I would describe it as a ‘bluebird day’, but every day is a ‘bluebird day’ around here.