User:Candyapple13/Mountain bluebird

Breeding
This species also can be a powder blue or with a gray chest.

The male can be seen singing from bare branches. The singing takes place right at dawn, just when the sun rises.

Mountain bluebirds nest in pre-existing cavities or in nest boxes. In remote areas, these birds are less affected by competition for natural nesting locations than other bluebirds. Mountain bluebirds are monogamous. After the couple decides together on an ideal nesting site, the female will typically build their nest themselves out of thin, dry material from the surrounding landscape while the male protects the area, defending against unwelcome visitors. It is true, though, that both males and females fiercely protect the nest. Once the nest is built, the female will lay an egg a day. Eggs are pale blue and unmarked, sometimes white. The clutch size is four or five eggs and she will incubate them for about two weeks. Young are naked and helpless at hatching and may have some down. The young will usually take about 21 days before they leave the nest, and it can take up to two months to raise fledglings to a stage of development at which they are able to fend and provide for themselves.

Mountain bluebirds are cavity nesters and can become very partial to a nest box, especially if they have successfully raised a clutch. They may even reuse the same nest, though not always. These birds will not abandon a nest if human activity is detected close by or at the nest. Because of this, they can be easily banded while they are still in the nest. The threats of predation for those that dwell in nesting boxes are mostly from house cats, raccoons, and the parasitic blowfly, Apaulina stalia.

< old edit/ > Feeding
During the summer, the diet of Mountain bluebirds predominately consists of insects; while, in the winter months they eat mostly berries (like Juniper berries, Russian-olive berries, elderberry, etc.) and fruit seeds (such as mistletoe seeds and grapes, just to name a few). These birds hover over the ground and fly down to catch insects, also flying from a perch to catch them. The first technique takes up to 8 times the energy of sitting on a perch and waiting. They may forage in flocks in winter, looking for grasshoppers. Mountain Bluebirds will come to a platform feeder with live meal worms, berries, or peanuts.

< new edit/ > Environmental Conditions
Anthropogenic noise, mostly human caused, has a negative effect on the mountain bluebird’s fitness. When a mountain bluebird is exposed to this noise, not only does it cause decreased corticosterone levels in adults and nestlings, but it also increases acute stressor corticosterone levels and reduces the fitness of these birds. When these noises are near nesting sites, there is a lower occupancy of the mountain bluebird at these sites due to the cost of fitness it has on them, such as reduced hatching success. < /new edit>