Measurements
Both Sexes
- Length
- 6.3–7.5 in
16–19 cm - Wingspan
- 11.4–12.2 in
29–31 cm - Weight
- 0.8–1.6 oz
23–45 g
Other Names
- Grive à dos olive (French)
- Zorzal de Swainson (Spanish)
Cool Facts
- The "russet-backed" Pacific population has more reddish plumage and a slightly different song than the "olive-backed" birds in the rest of the range. The russet-backed birds winter in Central America while the olive-backed ones winter in South America.
- The Swainson's Thrush is the only woodland thrush whose song goes up in pitch.
Habitat
Forest
- Breeds primarily in coniferous forests, especially spruce and fir. Also in riparian woodlands in California.
- Winters in mature tropical forest and secondary forest.
Food
Insects
Berries and insects.
Nesting
Nesting Facts
- Clutch Size
- 1–5 eggs
- Egg Description
- Blue to greenish blue with reddish or brown speckles.
- Condition at Hatching
- Helpless with some sparse down.
Nest Description
Nests in shrubs in forest understory. Nest an open cup of grasses, plant stems, moss, and small twigs, lined with skeletonized leaves, rootlets, lichens, or moss.
Nest Placement
Shrub
Behavior
Foliage Gleaner
Forages near ground, but higher in understory than other thrushes. Occasionally fly-catches. In winter follows army ant swarms.
Conservation
Least Concern
Not listed nationally; populations appear to be declining.
Credits
- Mack, D. E., and W. Yong. 2000. Swainson's Thrush (Catharus ustulatus). In The Birds of North America, No. 540 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.