Bewick’s Wren, Thryomanes bewickii

Bewick’s Wren, Thryomanes bewickii eremophilus. Photograph taken within a residential community in Hereford, Arizona, February 2007. Photograph and identification courtesy of Bob Behrstock, Sierra Vista, Arizona (naturewideimages.com).

Bewick’s Wren, Thryomanes bewickii eremophilus. Photograph taken within the greater Palm Springs area of southern California, March 2021. Photography courtesy of Dr. Tom Bartol, Carlsbad, California.

Background and Identification

Bewick’s Wren, Thryomanes bewickii eremophilus, is one of fifteen subspecies of Bewick’s Wren, eight of which are found in Mexico. They are a member of the Troglodytidae Family of Wrens, which has eighty-six members placed in nineteen genera, and the only global species in the Thryomanes Genus. Bewick’s Wrens are known for their sweet and soft songs and can be commonly spotted on farms, in barns and near livestock. They are active foragers, normally found as solitary individuals that glean insect adults, eggs, larvae, and other small invertebrates. They have life spans of up to eight years. In Mexico, they are known as Cucarachero Colinegro.

Bewick’s Wren is a mid-sized songbird. The sexes are monomorphic, meaning they are similar in size and appearance. The average length of the Bewick’s Wren is 13 cm (5.1 inches) and their average mass is 11 g (0.39 oz). They are easily recognized by their white eye-line, white breast, and tail feathers that are barred with black, and tipped with white spots. Their upper parts are brown to grayish brown; the throat and underparts are whitish and washed gray on the sides and flanks. Their upper mandibles are blackish or of a dusky horn color, with a paler tomia. The lower mandible is paler than the upper. Their iris is brown or auburn, and their legs and feet are dull pale brown, drab, or horn (beige) colored. Juveniles have dusky grey edges on their feathers and underparts, forming scalloped-shaped plumage.

Habitat and Geographical Range

Bewick’s Wren is found in arid bushy areas, scrub and thickets in open country, open and riparian woodland, and chaparral away from humans at elevations up to 1,740 m (5,700 ft). A chaparral is any landscape that is dry and dominated by scrubs. Although mainly sedentary, they make some short-distance migrations for food and water.

Bewick’s Wren is a year-round non-migratory resident of Mexico being found within Baja California and Baja California Sur and from northeast Sonora to northern and western Nuevo León south through the interior to central Oaxaca, western Puebla, and west-central Veracruz. The eremophilus subspecies is found in west-central Mexico in the states of northeast Sonora, Chihuahua, and Coahuila south to northern Zacatecas. There are some isolated populations in the Eastern United States, but these have declined significantly in the last few decades.

Common Misidentifications

In North America, the Bewick’s Wren is most similar to the Carolina Wren,  Thryothorus ludovicianusn, but Bewick’s Wren is smaller, more slender, and has more grey in their plumage. Carolina Wrens also do not have white spots on their tail.

Conservation Status

From a conservation perspective, Bewick’s Wren is currently considered to be of Least Concern with stable, widely distributed populations. However, their populations east of the Mississippi River have virtually disappeared and those west of the Mississippi have declined. These declines are due to habitat loss, competition with House Wrens, and environmental changes.