Eastern Bluebird
Sialia sialis
Eastern bluebirds measure 16–21 cm (6.3–8.3 in) long, span 25–32 cm (9.8–12.6 in) across the wings, and weigh 27–34 g (0.95–1.20 oz). Male bluebirds have a bright head, back, and wings. Their breast is a brownish red. Females are lighter with gray on the head and back and some blue on their wings and tail. In females, the breast is usually lighter in color than in males, and is more orange.
ID text from Wikipedia, CC BY-SA 4.0
Mountain Bluebird
Sialia currucoides
The mountain bluebird is 15.5–18 cm (6.1–7.1 in) in length, weighs 24–37 g (0.85–1.31 oz), and has a wingspan of 11.0-14.2 in (28-36 cm). It is sexually dimorphic in the color of the plumage but the sexes are similar in size. An adult male is bright turquoise-blue above and somewhat lighter blue underneath but with a white lower belly. An adult female has duller blue wings and tail, grey breast, grey crown, throat and back. In fresh fall plumage, the female's throat and breast are brownish near the flank, contrasting with white tail underparts.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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