Pacific and Winter Wrens

Prior to 2010, "Troglodytes troglodytes", the "Winter Wren", was considered one species.  However, research revealed a genetic split between the wrens found in the western North America, eastern North America, and Eurasia.  They were split into three distinct species in 2010, with the two North American populations named Pacific Wren and Winter Wren.  The Pacific Wren is found in the humid forests of the Pacific Northwest, while the Winter Wren is found in eastern North America.  Research indicates a genetic split between the two species going back at least 4 million years, and evidently the two populations do not commonly interbreed.  They are distinctly separated by geography, and South Dakota is one area where both the Pacific and Winter Wrens may be seen, with Pacific Wrens likely found in the Black Hills, while those birds found in the eastern part of the state are likely Winter Wrens. 

Both birds are fond of dense forest undergrowth, often staying out of sight as they forage along the ground through thickets and fallen logs.  While often difficult to spot, during breeding season the males will sometimes flit up to higher perches to sing extremely long complex songs, lasting 6-8 seconds or more and consisting of over a hundred separate notes.  In addition to genetic differences and differences in range, the males' songs also are distinctly different between the two populations.  Note the photo to the right is of a Pacific Wren, taken along the Oregon Coast, while the photo found below is of a Winter Wren.  All of the "additional photos" found at the bottom of the page are of Pacific Wrens.

Habitat: During the summer breeding season, they are primarily found in moist conifer forests with a dense understory, often near water.  They winter in similar forest habitats with dense understories, although they will use deciduous and mixed forests as well as conifer forests.

Diet: Primarily feeds on insects and spiders, as well as snails, millipedes, tiny fish, and berries.

Behavior: Often forages low in dense thickets and undergrowth, in vegetation and also along the ground.  They may also occasionally forage along streams and pick items from the water's surface.  Unlike some other wren species, both Pacific and Winter Wrens tend to utilize heavy cover even when males are furiously singing their territorial songs.  The birds are often much easier to hear than see.

Breeding: Non-breeder in South Dakota

Song:  A very high-pitched notes with rapid trilling interspersed.  Click here to listen to the Winter Wren's song.  Click here for the Winter Wren's call.

Migration: Even prior to the species split into Pacific and Winter Wrens, major differences were found between migration patterns in western and eastern birds.  Pacific Wrens are primarily permanent residents along much of the Pacific Coast, all the way up to through the southern coast of Alaska, although some movements to lower elevations may occur in the fall.   Winter Wrens summer in the southern half of Canada, the Great Lakes region, and New England, while wintering in the eastern U.S. as far north as Illinois, Ohio, and New York and southward to the Gulf Coast.  Some Winter Wrens are also evidently permanent residents in parts of the Appalachians.

Similar Species: House Wren

Conservation Status: Numbers appear to be stable.

Further Information: 1) Wikipedia - Winter Wren

2) Cornell Lab of Ornithology - Winter Wren

Bottom Photo (Winter Wren) - Out-of-state photo, Courtesy of Norman Smith.