Friends of Salter Grove logo
Menu

Swainson's Thrush

Catharus ustulatus
Turdidae
Buffy eye ring, large dark spots on breast, ...
... and brown upperparts
Uniformly brown back of Swainson's Thrush versus ...
... Hermit Thrush with rufous tail
Also a thrush, American Robin has conspicuous plumage
Hermit Thrush usually undetected in forest except when ...
... singing its haunting flutelike notes during mating season
Many insects consumed for producing eggs ...
... usually 1 to 5 eggs per clutch
Insects also needed to feed ...
... juvenile from this stage ...
... to near adult size
Fruits are added to diet when available
Russet-backed population winters in Central America
Olive-backed form winters in South America
While on wintering grounds, feeds on fruits ond ...
... mooches on insects fleeing from Army Ants
Rests with fellow night migrants by day

Bird sightings for Salter Grove date back to 2002, but the Swainson's Thrush was only first recorded in late April 2024, along the Upland Trail.  It is a regular spring and fall migrant throughout Southern New England but is very easy to miss because its olive-brown plumage blends well with its preferred habitat in dense understory 

It breeds in coniferous forests across Canada, Alaska and the northern United States as well as in forested areas along the Pacific coast and in the Rockies, always favoring areas of dense vegetation.  Pacific coastal populations have russet brown backs and winter in Central America.  The olive-brown back of the Swainson's Thrush observed at Salter Grove is representative of the continental populations that winter in South America.

Even when it is on its breeding grounds and is relatively abundant, the Swainson's thrush is more likely heard than seen.  The haunting flute-like notes of its song is unforgettable and is used to both attract females and repel males from a territory during the breeding season.

The Swainson's Thrush is in the same family as the American Robin.  Like other thrushes, it mostly feeds on insects during the breeding season and adds fruits and berries in fall and winter.  While on its South American wintering grounds, it joins resident birds that feed on the swarms of insects fleeing from advancing hordes of army ants.

Many birds die during migration because of starvation, predation or bad weather.  Being a night migrant, the Swainson's Thrush additionally suffers mortality from crashing into windows, buildings, and communication towers.  It is consistently near the top of the list of such fatalities.  Unfortunately, a recent study further revealed that even birds that manage to fly away after collision probably die shortly thereafter due to sustained injuries.