Three species of bluebirds reside in North America - the Eastern bluebird, Western bluebird, and mountain bluebird. Eastern bluebirds are found throughout eastern and central North America, from southern Canada to scattered populations in Mexico. Mountain and Western bluebirds reside in western North America, from Alaska to central Mexico.
All three species of bluebird are migratory but have different migratory patterns based on their region. Mountain bluebirds range the farthest north and, thus, migrate more regularly. Eastern and Western bluebirds are only partially migratory. In the warmer areas of their ranges, they are often year-round residents.
Location, winter weather, and food availability all play a role in determining if and when bluebird populations migrate. These are details we will discuss in-depth throughout the article. Read on to discover more about the migratory habits of bluebirds where you live!
Mountain Bluebird migrate on more of a regular basis, compared to the other types of bluebirds
When bluebirds migrate south depends on their region. Eastern bluebirds are known as partial migrants. They remain permanent residents throughout much of their range - the populations that migrate generally live farther north.
Bluebirds around the Great Lakes and Midwest depart these regions between mid-September and late November. Birds in the Northeast typically migrate south beginning in late September through December.
All populations of mountain bluebirds appear to be migratory. They spend the breeding season throughout the western mountain ranges of North America. The mountain bluebirds that live the farthest north will begin migrating south in early August. Most depart their summer territories between September and October.
Western bluebirds are also partial migrants and considered the least migratory of the three species. Birds in the Cascade Mountains of Oregon and Washington and the Rocky Mountains of Colorado and Idaho generally migrate short distances to the coast or lower elevations, such as the Lower Colorado River Valley. These movements occur between mid-August and November.
Western Bluebird perched on a tree
All three bluebird species migrate based on winter weather conditions and food availability. The birds in northern breeding grounds will fly south to escape harsh winters in the mountains and the Great Plains. If food availability is plentiful and the winters not too extreme, bluebirds will remain in or just south of their breeding grounds.
In regions such as the Northeast, the partially migratory Eastern bluebird does not migrate every year. They are more likely to remain year-round when wild or cultivated food sources are readily available. The birds expend far less energy and are more likely to survive when they do not migrate.
The same goes for the Western bluebird. Besides the populations living at high elevations in the Rocky and Cascade Mountain ranges, this species does not need to migrate south to warmer weather. On the other hand, mountain bluebirds must leave their far north and high elevation breeding grounds to survive.
Winter weather and food availability are the two main reasons for bluebird migration
How far bluebirds migrate depends on where they are flying from. Birds on the cusp of warmer regions such as the southeast or west coast may not migrate farther than a few hundred miles - if that. On the other hand, populations in the northernmost regions of their range may migrate over 2,000 miles between Canada and Texas or Mexico.
Eastern, Western, and mountain bluebirds all migrate in flocks. These groups are typically small (between 4 and 20 birds) but occasionally contain several hundred bluebirds. These flocks often remain together on their wintering grounds and split up as they fly back north in the spring.
A flock of mountain bluebirds during migration
Many Eastern and Western bluebirds are year-round residents throughout most of their range. Eastern bluebirds in the southern United States generally are not affected by winter conditions and scarce food sources. The same goes for Western bluebird populations in the southwest and west coast. These regions are warm enough for the birds to be permanent residents.
Populations in northern or mountainous regions typically migrate south in the fall to escape long winters and return north in spring.
Bluebirds in the northern regions of their range migrate south for winter. Eastern bluebirds residing in southern Canada and the northern United States generally migrate to Texas or the southeast. Mountain bluebirds leave their Rocky Mountain territories to winter in the southwest and lowland areas of Wyoming, Nebraska, and Kansas. High elevation populations of western bluebirds migrate to the west coast or southwest.
Eastern Bluebird perched on a birdbath during the winter, Louisiana, USA
Bluebirds are small and need to keep their energy levels up to survive cold weather. As they forage throughout the day, the birds will remain in close flocks to stay warm. Bluebirds will sleep in a well-protected tree cavity or even a nest box for warmth and protection at night.
Mountain bluebirds are migratory. Their range reaches from Alaska to central Mexico. Bluebirds spending the breeding season in Alaska and the Northern Rockies will migrate south, sometimes as far as Mexico. However, many populations only move to Wyoming, Colorado, Kansas, or Nebraska for winter.
Mountain Bluebird looking for food on the ground
Bluebirds migrate in flocks. Typically, these contain between four and twenty birds, but groups of several hundred individuals have been documented.
Bluebirds are partially migratory. Individuals living in the northernmost regions of their range nearly always move south for winter. Individuals in warmer climates generally do not need to migrate.
Typically, all bluebirds migrate from Michigan in winter to warmer climates in the southeast. However, residents in southern Michigan will remain during mild winters.
Bluebirds do not generally migrate from Ohio. The winters are mild enough for the birds to remain year-round. Ohio will see an influx of bluebirds from farther north during cold seasons.
Bluebirds do not migrate from North Carolina. The winters are generally mild and the bluebirds' food sources are plentiful.
Close up of an Eastern Bluebird overwintering in New Hampshire, USA
Bluebirds are year-round residents throughout Tennessee. They do not migrate from this region, but Tennessee typically sees an increase in bluebird populations from the north during winter.
Bluebirds typically migrate south from Maine for the winter. Winters here tend to be long and colder than bluebirds prefer. However, in milder years, birds in southern Maine will remain year-round.
Bluebirds generally migrate from northern Missouri in winter. Although, populations will remain in the southern portion of the state. Individuals from farther north also fly south to Missouri.
Some bluebirds migrate from Maryland, while others do not. It depends on the winter conditions and food availability.
Mountain Bluebird in flight
Most Pennsylvania bluebirds migrate south for winter, but others remain year-round residents. It often depends on food availability and winter conditions.
Bluebirds do not migrate from Virginia. They are year-round residents throughout the state, often overwintering in dense thickets that offer protection from the elements.
Some bluebirds will remain year-round in Massachusetts when winters are mild. However, most migrate from the state in the fall and return in the spring.
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