Washington · Summer breeder

Mountain Bluebirds in Washington

When mountain bluebirds are present in Washington, when they nest, which native Washington plants feed them, and how to host them in a USDA 4a–9a yard.

Thrushes (Turdidae)Mountain BluebirdSialia currucoides
Status in Washington
Summer breeder
Nesting window
May–July
Broods
1–2 per season
Hardiness zones
USDA 4a–9a
Nest box
1 9/16 in hole, 5 × 5 in floor, 5–10 ft

When to expect mountain bluebirds in Washington

Mountain Bluebirds are summer residents in Washington, arriving shortly before nesting begins in May and leaving after the young are independent. Through the season they feed on grasshoppers, beetles and caterpillars.

Marine west-coast climate west of the Cascades, semi-arid shrub-steppe to the east.

Nesting in Washington

Across Washington, mountain bluebirds typically nest from May–July. Nest site: cavity or nest box. Females lay 4–8 eggs, incubate for 13–14 days, and young leave the nest after 17–21 days.

Dry, sunny summers west of the Cascades; hot in the Columbia Basin.

  • Have boxes cleaned and mounted before April — mountain bluebirds begin prospecting ahead of egg-laying.
  • Use a 1 9/16 in entrance on a 5 × 5 in floor, mounted 5–10 ft.
  • Fit a pole baffle or hole guard; ventilation gaps and drainage holes are essential.
  • Clean out old nests after each brood and again after July.

Native Washington plants that attract mountain bluebirds

Of the regional native plants we track for Washington, these 8 provide food or cover mountain bluebirds use:

Smooth sumac
Rhus glabra · Shrub

Red fruit heads hang on through winter.

Tall goldenrod
Solidago altissima · Perennial

Insect-rich in fall and seed in winter.

Paper birch
Betula papyrifera · Tree

Catkin seed feeds redpolls and siskins all winter.

Chokecherry
Prunus virginiana · Shrub

Dark summer fruit and heavy caterpillar load.

Red-osier dogwood
Cornus sericea · Shrub

White fruit and red winter stems; good thicket cover.

Highbush cranberry
Viburnum trilobum · Shrub

Red fruit persists until late winter when other food is gone.

Rocky Mountain juniper
Juniperus scopulorum · Tree

Berry-like cones feed bluebirds, solitaires and waxwings in winter.

Ponderosa pine
Pinus ponderosa · Tree

Seeds and bark insects; pygmy nuthatch and woodpecker habitat.

Feeding mountain bluebirds through the Washington year

Nests at high elevations in open country; takes nest boxes on fence lines.

  • Best foods: Mealworms.
  • In Washington's summer: offer water and insect foods; natural food is abundant.

Full diet breakdown for mountain bluebirds · Best feeder for mountain bluebirds

Frequently asked

Are mountain bluebirds in Washington year-round?

No. Mountain Bluebirds are summer breeders in Washington and leave for the winter.

When do mountain bluebirds nest in Washington?

Nesting in Washington typically runs May–July, with 1–2 per season. Clutches are 4–8 eggs, incubated for 13–14 days.

What native plants attract mountain bluebirds in Washington?

Smooth sumac, Tall goldenrod, Paper birch, Chokecherry, Red-osier dogwood, Highbush cranberry, Rocky Mountain juniper, Ponderosa pine are native plants in Washington that provide food or cover for mountain bluebirds.

What size birdhouse hole do mountain bluebirds need?

1 9/16 in, with a floor of 5 × 5 in mounted 5–10 ft.

Mountain Bluebirds in other regions

Other backyard birds in Washington

Sources

  1. Mountain Bluebird — All About Birds, Cornell Lab of Ornithology
  2. Mountain Bluebird life history — Cornell Lab of Ornithology
  3. Mountain Bluebird — Audubon Guide to North American Birds
  4. NestWatch nest box plans and species requirements — Cornell Lab
  5. eBird region overview and bar charts — Washington
  6. USDA Plant Hardiness Zone Map (2023)
  7. Audubon Native Plants Database

Timing reflects typical patterns for the region as a whole; local dates vary with elevation and year. Check the linked eBird bar charts for your county.