Wrens: Troglodytidae

Physical characteristics: The house wren can range in length from 4.6 to 5 inches (11.5 to 12.5 centimeters) with a weight of 0.3 to 0.4 ounces (8 to 11 grams). The bird is plain, mostly gray-brown on its upperparts. It has pale gray underparts, narrow black bars on the sides and lower belly, with wings and tail that have a narrow black barring. Its brown eyes have a pale streak above them, and a narrow pale eye ring. The bill is thin and slightly curved downward. Both sexes are similar, and the young have a dusky mottling on their breasts.

Geographic range: The house wren can be found across North America from the Canadian province of New Brunswick all the way The house wren is found throughout North America, in northern areas during the breeding season and farther south during the winter. (Joe McDonald/Bruce Coleman Inc. Reproduced by permission.) south to California and west to central Alberta and southern British Columbia. It migrates in winter south of its breeding grounds to areas that include South Carolina west to southern Arizona and south to the Mexican state of Oaxaca (wah-HAH-kah).

Habitat: The house wren prefers to dwell in open country with brushy areas, and among abandoned farmland, forest edges, and in well-vegetated suburban areas, as well as open deciduous and coniferous forests in the western part of North America.

Diet: The house wren forages in tangled vegetation and is primarily a carnivore, eating invertebrates that include spiders, caterpillars, and other bugs; it also eats small amounts of vegetation.

Behavior and reproduction: House wrens are either found by themselves or in pairs. They are loud and obvious in their behavior, easily noticeable. They can be bold. When males are beginning to mate, they create "dummy" nests as a part of the courtship ritual. The female eventually joins him, inspecting the nests and making the decision about which one is best for the breeding nest. The bird is a cavity nester, mostly building their nests in such places as abandoned woodpecker holes or tree cavities, or even hornets' nests that are no longer being used. They have also adapted to human-made nest boxes and other artificial nesting sites. The female lays four to eight eggs, which are whitish with small reddish brown spots. Eggs are incubated for thirteen to fifteen days, and done by the female. The young are born helpless, blind, and naked, and stay in the nest for twelve to eighteen days after hatching. The house wren has two to three broods a year.

Cactus wrens and people: This common bird is popular with humans due to being so familiar and so adaptable to artificial nests; as a result it is one of the best-studied birds in America.

Conservation status: These wrens are not threatened. ∎