Spot the Sky-Blue Beauty

The mountain bluebird is an important species to study. Understanding the biology, habitat, and population dynamics of the mountain bluebird can provide valuable insights into the health and well-being of the ecosystems they inhabit, and inform conservation and management efforts to protect this species and its habitats.

The traditional Blackfoot name for the mountain bluebird is pi'ksíí.

Mountain Bluebird (Sialia currocoides)

Similar Species:

  • Eastern Bluebird (Sialia sialis)

  • Western Bluebird (Sialia mexicana)

Keys to identification.

Male mountain bluebirds are known for their striking, vibrant sky-blue plumage, while female mountain bluebirds are more muted with a grayish-blue coloration and pale blue wing-tips and tail.

Habitat & Behaviour

Mountain bluebirds prefer sparsely treed meadows or prairie grasslands and open forest areas with fence posts, scattered trees and bushes for perching.

In the winter months they flock together in groups and can be found in mixed flocks with western bluebirds, sparrows, and cedar waxwings. They can usually be found perching on fence posts, barbed wire or tree branches.

They migrate in groups up to 50 starting in March. They move north slowly stopping often to feed. They are fairly hardy and can withstand short cold snaps but can starve if there are prolonged cold temperatures.

In breeding months they can be found in pairs. As they are highly aggressive they require space between nesting sites.

Diet & Feeding Behaviour

The mountain bluebird primarily feeds on insects such as beetles, flies, wasps, and caterpillars, which they hunt by perching on a branch or hovering above a field and then swooping down to catch their prey. They are also known to feed on insects on the ground, especially in the winter when their preferred food sources are less abundant. They also eat more berries such as mistletoe, juniper, hackberry, and other plants in the winter months.

Mountain bluebirds have a distinctive feeding behavior where they swallow their food whole, and then regurgitate the indigestible parts, such as the exoskeleton of insects, in the form of pellets. This helps them to extract more nutrition from their food and maintain a healthy digestive system. During the breeding season, the male mountain bluebirds will feed the female and their young, bringing back food to the nest several times a minute. This feeding behavior helps to ensure the health and survival of their offspring.

Migration & Distribution

The mountain bluebird is a widespread species found throughout western North America, ranging from Alaska to Mexico. They are most commonly found in open areas such as meadows, prairies, and alpine tundra, and are known to occupy a variety of habitats including forests, deserts, and grasslands.

They migrate late in the fall and early in the spring. Migration timing is largely dependent on food abundance.

Mountain Bluebirds are found mostly in the south and west of the province.

Life Cycle of a Mountain Bluebird

  • Nest Building

    Nest building takes 4-7 days. Females play the largest role in nest building. They gather most of the material and make cup shaped nest. Most of the nests are made of dry grasses but can also include shreds of bark, pine needles, twigs, straw, horse or deer hair. Occasionally there will be a few feathers in the nest or plastic strings.

  • Egg Laying

    Eggs are laid 1-2 days after the nest is complete. Females lay approximately 1 egg per day. First clutches average five to six eggs and second clutches average four to five eggs The eggs oval and are usually light blue in colour but can be white.

  • Incubation

    Incubation last 13-15 days and begins with after the last or second last egg is laid. The females are the only incubators of the egg as she is the only one to develop a brood patch (a bare batch of vascularized skin on her abdomen). The female will leave to find food but the male does bring her food. Males will guard the nest.

  • Nestling

    Eggs generally hatch within 24 hours of each other. The young use a tiny “egg tooth” to break their way out of the shell. It will take them 17-21 days to develop into fledgelings. Nestlings are born naked with closed eyes and develop rapidly over the next two to three weeks. Both female and males take active part in feeding the young. They provide each nestling 3-4 feedings per hour from dawn till dusk! They also remove fecal sacs from the nest.

  • Flegling

    Mountain bluebirds leave the nest at 17-21 days of age and is dependent on food availability. To encourage the young to fledge the parents will begin to feed them less and less. Driven by hunger they leave the nest. Initially they can fly 70-90 m. They tend to perch on fence rails or tree branches. The parents will continue to monitor and feed the young for the next 10 days. The young will beg food from their parents by flapping their wings and making a “begging” call. The young will often remain with their parents after this time but can find their own food.

    After the young have fledged the family group appears to disappear. It is thought that they move away from their breeding grounds and form “fledging groups” with other bluebirds. More study is needed to understand the post-fledging dispersal.

  • Expected Life Span

    A mountain bluebird has an expected lifespan of 3 - 5 years.