- 5.1 in
- 0.3–0.4 oz
- Smaller than a House Sparrow; slightly larger than a House Wren
- Troglodyte de Bewick (French)
- Chivirín cola obscura (Spanish)
- The severe declines of Bewick's Wren in the eastern United States coincided with range expansion in the House Wren. It is suspected that the House Wren, which frequently removes eggs from nests in cavities, was directly responsible for the decline. The increased availability of nest boxes may have helped the spread of the House Wren, and therefore the decline of the Bewick's Wren.
- The male Bewick's Wren learns its song while still on the parents' territory. It learns the song not from its father, but rather from the neighboring territorial males. The song repertoire developed before the first winter is retained for life.
- This species is named after British engraver Thomas Bewick—a friend of pioneering bird artist John James Audubon, who collected the first recognized specimen. After collecting a bird in 1821 in Louisiana, Audubon saw another and wrote, "I refrained from killing it, in order to observe its habits.… It moved along the bars of the fences, with its tail generally erect, looking from the bar on which it stood towards the one next above, and caught spiders and other insects, as it ran along from one panel of the fence to another in quick succession."
- Courting Bewick’s Wrens normally form monogamous pairs. While they’re setting up house and even after the female has begun incubating eggs, the male and female often forage together. This may help the male prevent his partner from mating with another bird.
- A young male Bewick’s Wren learns to sing from neighboring adult males while he is coming of age in his parents’ territory. The songs he develops differ from his father’s, with a note changed here, a syllable there. The melodious signature he acquires between the ages of about 30 and 60 days will be his for life.
- A Bewick’s Wren’s life starts off perilously. House Wrens may eject eggs from its nest; both eggs and nestlings can become lunch for rat snakes and milk snakes, and domestic cats go after nestlings. Adulthood isn’t safe either: mature birds can fall prey to roadrunners, rattlesnakes, or hawks.
- At the sound of approaching humans, a female Bewick’s Wren incubating eggs usually flushes quietly from her nest cavity, but remains nearby and scolds. Some females, however, sit tightly on their eggs even when disturbed.
- In his 1889 Ornithology of Illinois, Robert Ridgway attested that “No bird more deserves the protection of man than Bewick’s Wren. He does not need man’s encouragement, for he comes of his own accord and installs himself as a member of the community, wherever it suits his taste. He is found about the cowshed and barn along with the Pewee and Barn Swallow; he investigates the pig-sty; then explores the garden fence, and finally mounts to the roof and pours forth one of the sweetest songs that ever was heard.”
Bewick’s Wrens favor brushy areas, scrub and thickets in open country, or open woodland. Depending on where you live, you may find them in chaparral-covered hillsides, oak woodlands, mixed evergreen forests, desert scrub, stands of prickly pear and other cacti, mesquite and century plant, willows and tamarisk, hedgerows, or suburban plantings. Bewick’s Wrens normally breed in areas that contain a mixture of thick scrubby vegetation and open woodland.
Bewick’s Wrens eat the eggs, larvae, pupae, and adults of insects and other small invertebrates. Common prey animals include bugs, beetles, bees and wasps, caterpillars, butterflies, moths, grasshoppers, crickets, flies, and spiders. Bewick’s Wrens also occasionally eat seeds, fruit, and other plant matter, especially in winter. Bewick’s Wren nestlings receive mostly caterpillars, spiders, grasshoppers, and insect pupae. Adults sometimes consume pebbles and mud, perhaps for nutrients or to help with the grinding digestion of their food.
- Clutch Size
- 3–8 eggs
- Number of Broods
- 1-3 broods
- Egg Length
- 0.6–0.7 in
- Egg Width
- 0.5–0.6 in
- Incubation Period
- 14–16 days
- Nestling Period
- 14–16 days
- Egg Description
- White with reddish-brown or purplish spots.
- Condition at Hatching
- Weight about 1.4 grams (1/20 ounce); eyes tightly closed; skin pink, with sparse down.
The Bewick’s Wren’s cup-shaped nest has a base of sticks, grasses, rootlets, leaves, moss, or other plant materials, depending on what the local environment provides. Many contain spider egg cases. The open cup may be lined with feathers, wool, hair, or plant down, with a final inner lining of snakeskin. The male initiates nest building; both sexes participate. The construction process usually takes less than 8 days, though sometimes it can stall for long periods and require weeks to complete. The nest is about 2.5 to 3 inches high and 4 or 5 inches in diameter, the cup about 1-2 inches deep and 2-2.5 inches in diameter.
Bewick’s Wrens usually build their nests in cavities or on ledges within 30 feet of the ground. Males often begin the process, with the female contributing equally by the end. Common sites include rock crevices and ledges, brush piles, abandoned woodpecker nest cavities, outbuildings, nest boxes, and abandoned automobiles.
Nimble and acrobatic, Bewick’s Wrens often hang upside down as they glean insects and spiders from trunks, branches, and leaves. They usually forage in the undergrowth less than 10 feet up, or peck at the ground between short hops. Occasionally they’ll catch insects on the wing. Seizing a prey animal in its bill, a Bewick’s Wren crushes it, shakes it, or bashes it against a branch. Having thus subdued its food, the wren swallows it whole. After a meal, this bird like many others may use its twig perch as a napkin, wiping its bill as many as 100 times. When it leaves the cover of vegetation, a Bewick’s Wren typically darts straight for its destination in a quick, level flight. A male’s weapon of choice for year-round territorial defense is his singing voice. Dueling crooners perch within about 20 feet of each other to trade a barrage of competing songs and harsh calls. Males may also give chase to fellow Bewick’s Wrens or House Wrens that impinge on their territory. (The House Wren usually wins.) During courtship, the male may feed the female, or spread his tail and turn from side to side; the female utters hoarse begging calls or a high clear note. The Bewick’s Wren often cocks its long tail and wags it from side to side, sometimes fanning the feathers.
Bewick Wren populations slightly declined from 1966–2011, according to the North American Breeding Bird Survey. Partners in Flight estimates the global breeding population at 5.6 million, with 71 percent spending part of the year in the U.S., 30 percent in Mexico, and 1 percent in Canada. They rate a 10 out of 20 on the Continental Concern Score and are not on the 2012 Watch List. Once common across the Midwest and eastern mountains, the Bewick’s Wren saw its population begin to plummet in the early twentieth century. The bird has now all but disappeared east of the Mississippi River, and has also declined in western parts of its range. The House Wren is a likely culprit. Drawn to the same nesting sites as Bewick’s, this widespread wren doesn’t hesitate to appropriate the other birds’ real estate, ejecting eggs and destroying nests. Humans may be inadvertently helping House Wrens usurp the Bewick’s Wren by allowing the reforestation of former farm fields, and also by providing nest boxes that get snapped up by House Wrens. Bewick’s Wren populations may also be falling prey to agricultural pesticide use, and to competition with the European Starling, House Sparrow, Carolina Wren, and Song Sparrow.
- Kennedy, E. D., and D. W. White. 1997. Bewick's Wren (Thryomanes bewickii). In The Birds of North America, No. 315 (A. Poole and F. Gill, eds.). The Birds of North America Online, Ithaca, New York.
- Dunne, P. 2006. Pete Dunne’s Essential Field Guide Companion. Houghton Mifflin, New York.
- Partners in Flight. 2012. Species assessment database.
- Sibley, D. A. 2003. The Sibley Field Guide to the Birds of Western North America. Knopf, New York.
- USGS Patuxent Wildlife Research Center. 2012. North American Breeding Bird Survey 1966–2010 analysis.
Primarily a year-round resident, with some short movements reported within Western states. Before eastern populations disappeared, some migration was reported from northern parts of the range south to Texas, the Gulf Coast, and northern Florida
If you live within the Bewick’s Wren’s range, you might attract this bird to your yard by landscaping with native shrubs such as willow, mesquite, elderberry, and chaparral plants, or by keeping a brush pile in your yard.
Find This Bird
Listen and watch for Bewick’s Wrens in dry, brushy or scrubby environments in western North America. These birds don't spend a lot of time in the open, so listen for the male's loud song during summer, or for raspy calls coming from tangles of shrubs.