Montana · Summer breeder

Western Bluebirds in Montana

When western bluebirds are present in Montana, when they nest, which native Montana plants feed them, and how to host them in a USDA 3a–6a yard.

Thrushes (Turdidae)Western BluebirdSialia mexicana
Status in Montana
Summer breeder
Nesting window
May–July
Broods
1–2 per season
Hardiness zones
USDA 3a–6a
Nest box
1 1/2 in hole, 5 × 5 in floor, 5–10 ft

When to expect western bluebirds in Montana

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

Continental — Rocky Mountain forest in the west, semi-arid Great Plains in the east.

Nesting in Montana

Across Montana, western bluebirds typically nest from May–July. Nest site: cavity or nest box. Females lay 2–8 eggs, incubate for 12–17 days, and young leave the nest after 19–25 days.

Warm, dry summers and a short growing season.

  • Have boxes cleaned and mounted before April — western bluebirds begin prospecting ahead of egg-laying.
  • Use a 1 1/2 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 Montana plants that attract western bluebirds

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

Smooth sumac
Rhus glabra · Shrub

Red fruit heads hang on through winter.

Bur oak
Quercus macrocarpa · Tree

Drought-hardy prairie oak with large acorns and a heavy insect load.

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.

Common hackberry
Celtis occidentalis · Tree

Sweet dry fruit on the branch all winter.

Feeding western bluebirds through the Montana year

Uses 1 1/2 in nest boxes in open oak and pine woodland; boxes have helped recovery in the Pacific Northwest.

  • Best foods: Mealworms, Suet nuggets.
  • In Montana's summer: offer water and insect foods; natural food is abundant.

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

Frequently asked

Are western bluebirds in Montana year-round?

No. Western Bluebirds are summer breeders in Montana and leave for the winter.

When do western bluebirds nest in Montana?

Nesting in Montana typically runs May–July, with 1–2 per season. Clutches are 2–8 eggs, incubated for 12–17 days.

What native plants attract western bluebirds in Montana?

Smooth sumac, Bur oak, Tall goldenrod, Paper birch, Chokecherry, Red-osier dogwood, Highbush cranberry, Common hackberry are native plants in Montana that provide food or cover for western bluebirds.

What size birdhouse hole do western bluebirds need?

1 1/2 in, with a floor of 5 × 5 in mounted 5–10 ft.

Western Bluebirds in other regions

Other backyard birds in Montana

Sources

  1. Western Bluebird — All About Birds, Cornell Lab of Ornithology
  2. Western Bluebird life history — Cornell Lab of Ornithology
  3. Western Bluebird — Audubon Guide to North American Birds
  4. NestWatch nest box plans and species requirements — Cornell Lab
  5. eBird region overview and bar charts — Montana
  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.