As the pressure of population increasingly regiments us and crowds us closer together, an association with the wild, winged freedom of the birds will fill an ever growing need in our lives. – Edwin Way Teale, introduction to Songbirds in Your Garden, 1953
Mama III has been a busy little bluebird. She’s laid an egg on six consecutive days. The embryos will begin to develop when Mama starts incubation. She was in the box all morning, so she is incubating. The female birds seem to have an internal thermometer that knows when to warm the eggs and when to leave the box.
Bluebird eggs hatch in 12-14 days; I generally just calculate 13 to the hatch date. That means the chicks should hatch on 28 March. The little bluebirds have an egg tooth on top of their beak, but unlike most birds they don’t just break through the egg shell and bust out. Instead they cut all the way round the middle of the egg so that it falls in two halves. At this point the female eats the eggshell to replenish the calcium she lost in the egg laying process. Nature is generally efficient with little going to waste.
There will not be a lot of action during incubation. Bluebirds, their eggs and young are always at risk though. The biggest risk for eggs is House Sparrows or some other cavity nester destroying the eggs in order to seize the nesting site. I have the Sparrow Spooker installed on the box which works pretty well. A nestbox built specifically for bluebirds has a ventilated roof and a hole that is not large enough for starlings and bigger birds to enter. There aren’t a lot of House Sparrows around, but it only takes one. I’m putting out the sparrow trap baited with white millet this afternoon. I always caution people thinking of putting up a bluebird box near their house that they must be willing to trap and euthanize sparrows or sooner or later, they will destroy eggs, kill babies or even an adult if trapped inside the box. I trap and euthanize about 60 annually.
Total chicks fledged from this site is 61.
First Brood 2016
- First sign of nest building 01 March
- Nest completed 07 March
- First egg 09 March
- Second egg 10 March
- Third egg 11 March
- Fourth egg 12 March
- Fifth egg 13 March
- Six egg 14 March
- Incubation begins 15 March