Bluebird Chivalry
I found a second clutch in my bluebird box consisting of
four eggs. Yippee! The first clutch back in March consisted of
five so if all goes well with this clutch the female will be the proud mom of
nine children.
A couple weeks ago I snapped a photo of one of the juveniles
from the first clutch. It had been
hanging out on the low hanging limb of an oak studying the ground for something
to eat as it had been schooled to do by its parents. It eventually flew over to the box that was
its birth place, probably waiting to see if mom or dad might come along with something feed it. Later I was able to capture a photo of the
adult female bringing in a fresh strand of pine straw to add to her nest, which
would eventually hold the second clutch of four eggs I spoke of earlier.
Raising nine kids takes lots of work. During the incubation period the female
spends most of her time in the box keeping her eggs warm. Only the female does this because only she
has what is known as a brood patch. Towards
the end of the egg laying period she sheds feathers on her belly exposing an
area of skin that is concentrated with blood vessels that are close to the
skin’s surface. The heat released from
this area is what keeps the eggs warm during development. She must also keep a close eye out so that
predators don’t make a meal out of them.
Wrens are also prominent in this area and are known to enter bluebird
housing and “pip” eggs and kill bluebird nestlings, so she has to be wary of
these also. She's so busy tending to her eggs that she doesn't have much time to even feed herself. Ever so often she would leave the confines of
the box and fly up to an airy perch on an electrical wire nearby, still all the
while keeping a close eye on the wooden box that held her precious eggs. I began to wonder where the male was. I glassed the trees in search of him and then
moments later he shows up.
He had been out fly-catching for insects for his hard
working, famished mate. There he stood
on top of the nest box with a beak full of bugs.
The female drops like a stone from her high
perch and lands on the box as if she’s been expecting him. She opens her beak and he hops to her side and
places the insects ever so gently into her mouth. What a sight to see!
Labels: Bluebird, brood patch, carolina wren