The bluebird carries the sky upon his back.– Henry David Thoreau
Not a lot to chronicle or photograph during incubation. It’s the boring segment of the brooding cycle. The eggs in a clutch don’t start developing until incubation begins when the female sits on them. That’s the theory at least. But sometimes during excessively hot weather the eggs may start developing just from heat in the box causing eggs to hatch at different times. And sometimes if the heat is excessive, the eggs don’t develop at all. Early season broods are more successful than the summer broods due to heat.
Mama II laid her last egg on 06 July, so if we calculate 13 days from the day I first saw her incubating that puts the hatch date at ~ 21 July. I’d bet on a date a day or two earlier than later in this heat. We’ll see.
The bluebirds have some new neighbors in the back yard. A pair of Brown Thrashers built a nest in a neighbor’s rose bush. One of their prematurely fledged babies took up residence in my yard and the thrashers are spending a lot of time caring for the young one. They are big birds and fierce predators, but I’ve not seen any conflict between them and the bluebirds. Daddy has an innate sense of which birds are a threat to his family and which ones aren’t. He ignores the presence of the thrashers, unless they try to land on the box. That’s off limits to everyone.
Click photos to enlarge.
Second Brood Summary
- First sign of nest building 28 June
- Nest completed 01 July
- First egg laid 03 July
- Second egg laid 04 July
- Third egg laid 05 July
- Fourth egg laid 06 July
- Incubation begins 08 July