Thrushes (Turdidae)

Western Bluebird

Sialia mexicana. Insects in summer; berries in winter.

Thrushes (Turdidae)Western BluebirdSialia mexicana
Scientific name
Sialia mexicana
Length
6.3–7.5 in
Weight
0.9–1.1 oz
Nest
Cavity or nest box
Entrance hole
1 1/2 in
Clutch
2–8 eggs
Incubation
12–17 days
Broods
1–2 per season

Identification

  • Male deep blue with a rusty breast and blue throat
  • Rust often extends onto the back
  • Female grey-brown with pale rust breast

Voice

Soft 'pew' calls.

Diet and feeding

Western Bluebirds by state and province

RegionStatusNesting
ArizonaYear-round residentMarch–July
British ColumbiaSummer breederMay–July
CaliforniaYear-round residentMarch–July
ColoradoSummer breederApril–July
IdahoSummer breederApril–July
MontanaSummer breederMay–July
NevadaYear-round residentApril–July
New MexicoYear-round residentApril–July
OregonYear-round residentApril–July
TexasWinter visitor—
UtahYear-round residentApril–July
WashingtonSummer breederApril–July

Frequently asked

What do western bluebirds eat?

Insects in summer; berries in winter. At feeders: mealworms, suet nuggets.

How big is a Western Bluebird?

6.3–7.5 in long and 0.9–1.1 oz.

Do western bluebirds use birdhouses?

Yes — a 1 1/2 in entrance, 5 × 5 in floor, mounted 5–10 ft.

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

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.