Swainson's Thrush

Bird of the Month: Swainson's Thrush

By Hugh Jennings

PC: Mick Thompson (Swainson’s Thrush)

PC: Mick Thompson (Swainson’s Thrush)

Scientific Name: Catharus ustulatus

Length 5.5 in

Wingspan 14 in

Weight 0.56 oz

AOU Band code NRWS

The Swainson’s Thrush (SWTH) is 7 to 7-1/2 inches long. They are fairly common in the summer, usually arriving in our area from the middle of May to June. They head south in late summer for Mexico and South America. They are found in moist woods, swamps and thickets. The SWTH, both male and female are the same, uniformly brownish above and white below. They have buffy lores and a bold buffy eye ring, bright buffy breast with dark spots, and brownish-gray sides and flanks.

The song is a beautiful ascending series of flute-like notes that seem to disappear in the stratosphere. The call note is an abrupt "whit." The SWTH feeds on the ground and in foliage, and eats a variety of insects, spiders, and berries. Their nests are located from 2-40 ft. above the ground on horizontal branches. The nest is made of twigs, bark, moss, grass, plant fibers, lichens and skeletonized leaves. The female lays 3-5 eggs, light blue with brown spots and about 0.8 inches long. Incubation takes 11-14 days and the young fledge in another 10-14 days.

The Swainson’s Thrush is usually heard more than seen. Locally, it can frequently be heard at Marymoor Park, Farrel-McWhirter Park, Lake Hills Greenbelt, and Redmond Watershed Preserve.