Swainson's thrush

Swainson's thrush, also known as the olive-backed thrush, is a medium-sized bird from the genus Catharus. Featuring understated colors and a melodious, flute-like song, this bird is a delightful sight and sound for bird watchers. It derives its name from William Swainson, an English ornithologist.

Swainson's thrush breeds in coniferous forests with abundant undergrowth, primarily in Canada, Alaska, and the northern United States. They are also found in deciduous forests along North America's Pacific coast. As winter approaches, these birds migrate to warmer regions, traveling as far south as Argentina and southern Mexico. Notably, there are two main groups: coastal and continental, each with distinct migration patterns. On rare occasions, individuals may even be spotted in western Europe or northeast Asia. In regions where their range overlaps with the hermit thrush, Swainson's thrush can sometimes be displaced.

Measuring about 16-20 cm in length, Swainson's thrush can be identified by its wing patterns and body mass. They primarily consume insects, fruits, and berries, foraging on the forest floor and among trees. For nesting, they construct cup-shaped nests on horizontal branches.

There are four recognized subspecies of Swainson's thrush, each exhibiting distinct genetic differences indicative of a rapid range expansion following the last ice age. Swainson's thrush is the oldest North American member of its genus and has evolved similarly to other North American species. The genetic variations and migratory behaviors of these subspecies suggest historical adaptations that are not yet perfectly aligned with their current locations.