Hermit Thrush
Catharus guttatus
This species measures 15 to 18 cm (5.9 to 7.1 in) in length, spans 25 to 30 cm (9.8 to 11.8 in) across the wings and weighs 18 to 37 g (0.63 to 1.31 oz). Among standard measurements, the wing chord is 7.8 to 11.1 cm (3.1 to 4.4 in), the bill is 1.6 to 1.9 cm (0.63 to 0.75 in) and the tarsus is 2.7 to 3.3 cm (1.1 to 1.3 in). It is more compact and stockier than other North American Catharus thrushes, with relatively longer wings. The hermit thrush has the white-dark-white underwing pattern characteristic of Catharus thrushes. Adults are mainly brown on the upperparts, with reddish tails. Voice: The hermit thrush's song has been described as "the finest sound in nature" and is ethereal and flute-like, consisting of a beginning note, then several descending musical phrases in a minor key, repeated at different pitches. It often sings from a high open location.
ID text from Wikipedia, CC BY-SA 4.0
Swainson's Thrush
Catharus ustulatus
This species is 16–20 cm (6.3–7.9 in) in length. The wingspan averages at 30 cm (12 in) and the wing chord is 8.7–10.5 cm (3.4–4.1 in). The bill measures 1.5–1.9 cm (0.59–0.75 in) in length and the tarsus is 2.5 to 3.1 cm (0.98 to 1.22 in) long. This species' body mass can range from 23 to 45 g (0.81 to 1.59 oz). This thrush has the white-dark-white underwing pattern characteristic of Catharus thrushes. Adults are brown on the upperparts. The underparts are white with brown on the flanks; the breast is lighter brown with darker spots. They have pink legs and a light brown eye ring.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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