The northern house wren (Troglodytes aedon) is a very small passerine bird in the wren family Troglodytidae. It is found in southern Canada, the United States, and Mexico, and occurs in most suburban areas within its range.
Taxonomy
The species was formally described in 1809 by French ornithologist Louis Pierre Vieillot under the binomial name Troglodytes aedon. The specific epithet aedon is from Ancient Greek meaning "nightingale." The genus name troglodytes means "hole dweller," referring to the bird's tendency to disappear into crevices when hunting insects or seeking shelter.
Four subspecies are currently recognized:
- T. a. parkmanii – southwest and central south Canada, west and central USA to northern Mexico
- T. a. aedon – southeast Canada and eastern USA
- T. a. cahooni – southeast Arizona to central Mexico
- T. a. brunneicollis – central and southern Mexico
Several former subspecies resident in South America and the Caribbean are now treated as separate species, including the southern house wren (Troglodytes musculus), Cozumel wren, Kalinago wren, St. Lucia wren, St. Vincent wren, Grenada wren, and Cobb's wren.
Description
Adult northern house wrens are about 11 to 13 cm (4.3–5.1 in) long, with a 15 cm (5.9 in) wingspan, and weigh approximately 10 to 12 g (0.35–0.42 oz). The plumage is generally plain brown, with dark barring on the wings and tail. Upper parts range from dull greyish-brown to rich rufescent-brown, and underparts range from brown through buff and pale grey to white, depending on subspecies. They have a faint eye-ring and eyebrow, a long thin bill with a blackish upper mandible, and a black-tipped yellowish or pale grey lower mandible. The short tail is typically held cocked.
Behavior and Ecology
Diet: The northern house wren forages actively in vegetation, primarily eating insects such as butterfly larvae, beetles, and bugs, as well as spiders and snails.
Breeding: They construct a large cup nest in cavities, made from small dry sticks and lined with feathers, hair, wool, spider cocoons, bark strips, rootlets, moss, and other materials. Nest cavities are usually a few meters above ground and may be natural or man-made, including birdhouses. The clutch is typically between two and eight red-blotched cream-white eggs. Only the female incubates, for approximately 12–19 days, while the male provisions her with food. Young fledge after 15–19 days and are fed by both parents.
Northern house wrens are known for their aggressive behavior despite their small size. They occasionally destroy the eggs of other birds nesting in their territory by puncturing the eggshells, and may fill up other birds' nests with sticks to make them unusable.
Song: The bird's rich, bubbly song is commonly heard during the nesting season. There is marked variation in the song across individuals and populations.
Migration: Populations in the northern parts of the range migrate to the southern United States and Mexico for winter, returning to breeding grounds in late April to May and departing around September to early October.
Conservation Status
The northern house wren is classified as Least Concern on the IUCN Red List. It is common and widespread throughout most of North America and is not considered threatened.
