- 3.1–4.7 in
- 4.7–6.3 in
- 0.3–0.4 oz
- Larger than a Rufous Hummingbird, smaller than a Chestnut-backed Chickadee.
- Male Pacific Wrens build multiple nests within their territory. During courtship, males lead the female around to each nest and the female chooses which nest to use.
- Pacific Wren were considered the same species as Winter Wren until 2010 when researchers found that wrens in the West differed from birds in the East and from birds in Europe. Winter Wren was then split into three different species; the Pacific Wren of the West, the Winter Wren of the East, and the Eurasian Wren in Europe—the only wren species that occurs outside the Americas.
- Pacific Wrens may congregate near streams when salmon are migrating in the Pacific Northwest to cash in on the abundance of insects that are attracted to salmon carcasses.
- Some populations of Pacific Wrens move short distances after the breeding season and others stay in the same place year-round.
- Pacific Wrens sometimes pile into nest boxes to stay warm when the weather turns cold. Thirty-one individuals were found together in one nest box in western Washington.
- The oldest known Pacific Wren was a female and at least 6 years, 6 months old when she was recaptured and rereleased during banding operations in California in 2008. She had been banded in the same state in 2003.
The Pacific Wren lives in forested habitats from sea level to 12,000 feet in the western United States and Canada. They are most common in old-growth evergreen forests, but they also live in deciduous forests, mixed evergreen and deciduous forests, and aspen stands. Within these habitats they often live near water and in areas with fallen logs, dead trees and stumps, brush piles, and thick understory cover of mosses and ferns. During the nonbreeding season, some individuals move to lower elevations and use many habitats including scrub oak, pinyon-juniper forests, and sometimes parks and gardens.
Pacific Wrens are insectivores; they eat insects such as beetles, caterpillars, ants, as well as spiders, mites, ticks, millipedes, flies, and bees. They hop slowly on the ground or just above the ground inspecting crevices, decaying wood, upturned roots, and vegetation for food. They capture prey by picking it off surfaces or by probing in decaying bark. During the nonbreeding season, Pacific Wrens sometimes eat juniper berries.
- Clutch Size
- 1–9 eggs
- Number of Broods
- 1-2 broods
- Egg Length
- 0.6–0.7 in
- Egg Width
- 0.5–0.6 in
- Incubation Period
- 14–17 days
- Nestling Period
- 15–17 days
- Egg Description
- White eggs with small pale to reddish brown spots concentrated on the larger end of the egg.
- Condition at Hatching
- Nestlings are naked with only a few straggly down feathers.
Males build nests out of moss, bark, twigs, rootlets, grass, and other plant material they find close to the nest site to help with camouflage. Males and females line the nest with feathers and animal hair. Nest size varies depending on the size of the cavity and placement of the nest. At times, nests can be the size of a football.
Pacific Wrens build domed-shaped globular nests and also nest inside natural cavities. Males build nests often near streams in roots of upturned trees, under creek banks, in decaying logs, in hanging moss, or in dead trees. Females help line the inside of the nest, but do not build them. Nest height ranges from ground level to 23 feet above the ground.
Pacific Wrens fly short distances with rapid wingbeats in the understory. Their movements are rather mouselike as they scurry and hop along fallen trees and roots. They can also cling to the tree trunks similar to a Brown Creeper. Pacific Wrens are energetic birds that often bob their heads or bodies even when they are standing still. During the breeding season males vigorously sing from prominent perches in the understory. When a female enters a male’s territory, he continues to sing, flutters his wings, and cocks his tail side to side. During courtship, the male leads the female around to each of several nests he has built in his territory. The female then chooses which nest to use. Pacific Wrens maintain territories year-round, although territories often shrink during the nonbreeding season. Pacific Wrens do not form flocks with other species and are normally solitary or paired with their mate.
Pacific Wrens are fairly numerous and their populations were stable between 1966 and 2015, according to the North American Breeding Bird Survey. Partners in Flight estimates the global breeding population is 6 million, with 73% spending some part of the year in the U.S., and 41% in Canada. It is not on the 2016 State of North America’s Birds Watch List, and rates a 10 out of 20 on the Continental Concern Score. Although populations appear stable, their old-growth habitat is threatened by logging and management practices that remove downed logs, slash piles, and upturned roots which are important for nesting and foraging.
- Toews, D.P.L., and D. E. Irwin. 2012. Pacific Wren (Troglodytes pacificus). The Birds of North America (P.G., Rodewald, Ed.). Ithaca: Cornell Lab of Ornithology.
- North American Bird Conservation Initiative, U.S. Committee. 2016. State of North America’s Birds 2016 Report. U.S. Department of Interior, Washington, DC.
- Partners in Flight. 2012. Species assessment database.
- Sauer, J.R., J.E. Hines, J.E. Fallon, K.L. Pardieck, D.J. Ziolkowski, Jr., and W.A. Link. 2016. The North American Breeding Bird Survey, Results and Analysis 1966 – 2015, Version 01.30.2015 . USGS Patuxent Wildlife Research Center, Laurel, MD.
- USGS Patuxent Wildlife Research Center. 2016. Longevity records of North American Birds.
Resident to short-distance migrant. Pacific Wrens are year-round residents along the West Coast from Alaska to central California. They are also resident in some interior western states. Birds that breed in Canada migrate short distances to the south for the winter.
If you live within their breeding range, you may be able to attract one to your yard by installing a nest box. Be sure to have the nest box ready before the breeding season begins complete with a predator guard. Find plans to build your own nest box at NestWatch.
Landscaping with native plants can also attract Pacific Wrens. Maintaining areas with dense vegetation and brush piles can provide foraging and maybe even nesting opportunities. Learn more about landscaping with native plants at Habitat Network.
Find This Bird
Pacific Wrens are very vocal so listen for their rapid series of tumbling and trilling notes in old-growth forests in the West. When you hear their sweet song, patiently look in the understory for mouselike movements along decaying logs and in upturned roots. Early mornings during the breeding season are best times to find them perched in the open shaking as they sing.
Count the number of Pacific Wrens you see in your yard during the Great Backyard Bird Count.
Look for Pacific Wren nests and contribute valuable data about them through NestWatch and eBird.