House wrens feed primarily on small, terrestrial insects. The independent young and adults consume mostly spiders, beetles, and bugs while the nestlings are fed mostly grasshoppers, crickets, and caterpillars. Adults feed their young and supplement their own diet with sources of calcium such as mollusk shells. House wrens forage primarily in the woodland subcanopy, in shrubs and among herbaceous ground cover.
Animal Foods: insects
Primary Diet: carnivore (Insectivore )
Predators of house wrens include cats, rats, opossums, woodpeckers, foxes, owls, raccoons, squirrels, and various snakes. Adult house wrens respond to predators by chasing and striking at the predator while giving a loud, harsh alarm call.
Known Predators:
House wrens are small, squat birds without bold or characteristic markings. They have long, curved bills and, like other wrens, perch in a characteristic posture with their tail held erect. Their heads, napes, and backs are almost uniformly brown with very fine darker brown stripes. Their throats and chests are light grey, and they may have some black, dark brown, or pinkish spots on their flanks, tails, and wings. There is a faint, white eyebrow-like stripe above their eyes.
House wrens are usually 11 to 13 cm long and weigh 10 to 12 g. Males and females are identical in coloration, but males are slightly larger in some traits.
There are about 30 recognized subspecies of Troglodytes aedon. These subspecies are differentiated by plumage shading, amount of barring on flanks, variation in wing-to-tail proportions, and vocalizations.
Range mass: 10 to 12 g.
Range length: 11 to 13 cm.
Other Physical Features: endothermic ; bilateral symmetry ; polymorphic
Sexual Dimorphism: sexes alike; male larger
The oldest known house wren lived to be at least 7 years old. It is difficult to estimate the lifespan of these birds because they do not return to the same area every year.
Range lifespan
Status: wild: 7 (high) years.
Average lifespan
Status: wild: 108 months.
In the wild, house wrens live in open, shrubby woodlands. However, they were named for their preference for small town and suburban backyards and human-made bird houses. Small wood-lots and forest edges are also common habitats for these birds. Human farming and towns have created more good breeding habitat for the wren by breaking forests up into small chunks. This explains why house wrens have expanded their range and their population in North America has grown. During the winter, wrens live in thickets, shrubby and brushy areas, riparian forests, and savannas in the southern United States. In Mexico, they prefer tropical evergreen and semideciduous forests.
Habitat Regions: temperate ; tropical ; terrestrial
Terrestrial Biomes: forest
Other Habitat Features: urban ; suburban ; agricultural
House wrens are native to the Nearctic region. During the breeding season they live from southern Canada to southern Argentina, Chile and the Falkland Islands. They spend the winter in a narrower range; the southern limits of the United States, southwestern California east to Florida and south throughout the Gulf Coast and Mexico.
Biogeographic Regions: nearctic (Native ); neotropical (Native )
House wrens help to control insect populations. They also supply food for many different animals.
House wrens eat insects that may be considered to be pests by humans.
Positive Impacts: controls pest population
There are no known adverse affects of house wrens on humans.
House wrens are a very successful species because they have benefited from forest fragmentation and other human-induced habitat changes. They are quite tolerant of pesticides, habitat alteration and nest disturbance, allowing them to live and reproduce successfully even in human populated areas. This species is protected under the U.S. Migratory Bird Act.
US Migratory Bird Act: protected
US Federal List: no special status
CITES: no special status
State of Michigan List: no special status
IUCN Red List of Threatened Species: least concern
House wrens are widely known for their songs. While both sexes produce calls and songs, the males' songs are more complex. Altogether, 130 different song types are known from house wrens. Unmated males can sing for up to 10 minutes. Males with a mate often sing a "whispering song", which is very quiet, and is only sung around the time of copulation. The purpose of the quiet song may be to avoid revealing the location of his fertile mate to other males. The female sings during the first days of pairing when she responds to her mate's song.
House wrens also communicate using body language. If a predator approaches, males crouch and drop their wings, raise their back feathers, and lower their fanned-out tail.
Communication Channels: visual ; acoustic
Perception Channels: visual ; tactile ; acoustic ; chemical
House wrens are socially monogamous, meaning that one male and one female mate together and share parental responsibilities. However, some studies have shown that males that have surplus nest sites in their territory advertise for secondary mates. About 10% of the males in one study were polygynous. Adults often switch breeding partners between the first and second brood of a season. Breeding pairs do not last for any more than one season.
Mating System: monogamous
House wrens breed between late April and early September, with the majority of clutches started in mid-late May. The males are the first to return from migration and establish territory for nesting within a few hours/days of arrival. The females return in time to complete the nest after choosing a male. Females that nest at low latitudes (including most of the U.S.) and/or low altitudes generally raise two broods per season.
House wrens nest in tree cavities, such as old woodpecker holes. They prefer cavities closer to the ground with small entrances. The male begins building the nest by placing sticks in the bottom of the cavity. When the female arrives, she finishes building the nest. The female lays a clutch of 4 to 8 (usually 6) eggs, which she incubates for about 12 days. The chicks are altricial when they hatch, and are brooded by the female. Both parents feed the chicks, which fledge after 15 to 17 days. The chicks all leave the nest within a few hours of each other. After the chicks leave the nest, both parents continue to feed them for about 13 days.
House wrens are able to breed (have reached sexual maturity) when they are 1 year old, but some first time breeders skip the regular breeding time and choose instead to breed alongside the older birds who are attempting a second clutch in a season.
Breeding interval: House wrens may raise up to two broods each breeding season.
Breeding season: House wrens breed between late April and early September.
Range eggs per season: 4 to 8.
Average time to hatching: 12 days.
Range fledging age: 15 to 17 days.
Average time to independence: 13 days.
Average age at sexual or reproductive maturity (female): 1 years.
Average age at sexual or reproductive maturity (male): 1 years.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; oviparous
Average time to hatching: 14 days.
Average eggs per season: 7.
House wren chicks are completely helpless and dependant on their parents, who both care for the young. They fledge after about 15 to 17 days and all leave the nest within a few hours of each other. The parents continue to feed them for about 13 days after they leave the nest.
Parental Investment: altricial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Protecting: Female); pre-weaning/fledging (Provisioning: Male, Female, Protecting: Male, Female); pre-independence (Provisioning: Male, Female)
A small (4 ½ -5 inches) wren, the House Wren is most easily identified by its plain tan-brown back, tan breast, short tail (often held up at an angle), curved bill, and faint white eye-stripes. This species may be distinguished from the similar Carolina Wren (Thryothorus ludovicianus) by that species’ larger size and redder plumage and from Bewick’s Wren (Thryothorus ludovicianus) by that species’ larger size and brighter eye-stripes. Male and female House Wrens are similar to one another in all seasons. The House Wren breeds in southern Canada and the northern half of the United States, with other breeding populations occurring from southern Mexico and the West Indies to southern South America. In winter, populations breeding in North America winter in the southern half of the United States and northern Mexico. By contrast, tropical and South American House Wren populations are non-migratory. House Wrens inhabit a variety of semi-open habitats, including bushy fields, woodland edges, and scrub. This species has also adapted to life in well-vegetated urban and suburban areas, and its habit of nesting in artificial nest-boxes, also known as “bird houses,” has become part of this species’ English-language common name. House Wrens exclusively eat small insects. In appropriate habitat, House Wrens may be seen foraging for food on the ground or in the branches of bushes and shrubs. Birdwatchers may also listen for this species’ song, a rapid series of warbled notes. House Wrens are most active during the day.
A small (4 ½ -5 inches) wren, the House Wren is most easily identified by its plain tan-brown back, tan breast, short tail (often held up at an angle), curved bill, and faint white eye-stripes. This species may be distinguished from the similar Carolina Wren (Thryothorus ludovicianus) by that species’ larger size and redder plumage and from Bewick’s Wren (Thryothorus ludovicianus) by that species’ larger size and brighter eye-stripes. Male and female House Wrens are similar to one another in all seasons. The House Wren breeds in southern Canada and the northern half of the United States, with other breeding populations occurring from southern Mexico and the West Indies to southern South America. In winter, populations breeding in North America winter in the southern half of the United States and northern Mexico. By contrast, tropical and South American House Wren populations are non-migratory. House Wrens inhabit a variety of semi-open habitats, including bushy fields, woodland edges, and scrub. This species has also adapted to life in well-vegetated urban and suburban areas, and its habit of nesting in artificial nest-boxes, also known as “bird houses,” has become part of this species’ English-language common name. House Wrens exclusively eat small insects. In appropriate habitat, House Wrens may be seen foraging for food on the ground or in the branches of bushes and shrubs. Birdwatchers may also listen for this species’ song, a rapid series of warbled notes. House Wrens are most active during the day.
The house wren (Troglodytes aedon) is a very small bird of the wren family, Troglodytidae. It occurs from Canada to southernmost South America, and is thus the most widely distributed native bird in the Americas.[2] It occurs in most suburban areas in its range and it is the single most common wren. Its taxonomy is highly complex and some subspecies groups are often considered separate species. The name troglodytes means "hole dweller", and is a reference to the bird's tendency to disappear into crevices when hunting insects or to seek shelter.
The house wren was formally described in 1809 by the French ornithologist Louis Jean Pierre Vieillot under the current binomial name Troglodytes aedon.[3] The specific epithet is from the Ancient Greek aēdōn meaning "nightingale".[4] The type locality was designated as New York City by Harry Oberholser in 1934.[5][6]
There are 32 recognised subspecies.[7] These are sometimes divided into three distinct groups and one or several distinct island-endemic subspecies. Some or all of these are sometimes considered as distinct species.
It has also been suggested that the taxa from the Lesser Antilles represent one or more separate species, but there is less agreement as to their subdivision, because as far as they have been studied to date, there is little clear biogeographical structure among these populations.[8]
Three additional taxa from more oceanic islands have traditionally been included in the house wren, but are now considered as separate species:[7]
Adult house wrens are about 11 to 13 cm (4.3 to 5.1 in) long, with a 15 cm (5.9 in) wingspan and weigh about 10 to 12 g (0.35 to 0.42 oz).[9] Among standard measurements, the wing chord is 4.7 to 5.3 cm (1.9 to 2.1 in), the tail is 3.9 to 4.4 cm (1.5 to 1.7 in), the culmen is 1.1 to 1.3 cm (0.43 to 0.51 in) and the tarsus is 1.6 to 1.8 cm (0.63 to 0.71 in).[2] The subspecies vary greatly, with upper parts ranging from dull greyish-brown to rich rufescent-brown, and the underparts ranging from brown, over buff and pale grey, to pure white. All subspecies have blackish barring to the wings and tail, and some also to the flanks. All subspecies show a faint eye-ring and eyebrow and have a long, thin bill with a blackish upper mandible, and a black-tipped yellowish or pale grey lower mandible. The legs are pinkish or grey. The short tail is typically held cocked.[10]
This bird's rich bubbly song is commonly heard during the nesting season but rarely afterwards. There is marked geographical variation in the song, though somewhat more gradual than in the bird's outward appearance that can strikingly differ, e.g., on neighboring islands in the Caribbean.[8] Birds from far north and south of the species' range nonetheless have songs that differ markedly.[11]
Northern house wren song recorded in Rondeau Provincial Park (Ontario, Canada)
Southern house wren, São Paulo Botanic Garden (Brazil)
Southern house wren song recorded in Petropolis (Rio de Janeiro, Brazil)
Northern house wren
San Luis Obispo (California, USA)
Northern house wren recorded at Richardson Nature Center, Bloomington, Minnesota
In North America, the house wren is thought to achieve the highest density in floodplain forests in the western great plains where it uses woodpecker holes as nesting sites. In South and Central America it can be found in virtually any habitat and is, as indicated by its common name, often associated with humans. North American birds migrate to the southern United States and Mexico for winter. Most return to the breeding grounds in late April to May, and leave for winter quarters again around September to early October.[12] These birds forage actively in vegetation. They mainly eat insects such as butterfly larvae, beetles and bugs,[13] also spiders and snails. Southern house wrens rarely attend mixed-species feeding flocks.[14]
The nesting habits do not seem to differ significantly between the northern and southern house wrens. They usually construct a large cup nest in various sorts of cavities, taking about a week to build. The nest is made from small dry sticks and is usually lined with a variety of different materials. These include: feather, hair, wool, spider cocoons, strips of bark, rootlets, moss, and trash. The male wren finds dry sticks, which he adds to the nest. Once he is done, the female inspects the nest; but if she does not approve of the construction, she will throw any unwanted sticks to the ground. After this process, the female lines the nest. Nest cavities are usually a few meters above ground at most,[15][16] but occasionally on cliffs as high up as 15 m (49 ft) and more at least in southern populations; they may be natural or man-made, often using bird houses.
House wrens are feisty and pugnacious animals considering their tiny size. They are known to occasionally destroy the eggs of other birds nesting in their territory by puncturing the eggshell. Females that sang more songs to conspecifics that were simulated by playback lost fewer eggs to ovicide by other wrens. Female bird song in this species is, therefore, thought to have a function in competition and is not only displayed by males.[17] They are also known to fill up other birds' nests within its territory with sticks to make them unusable.[18]
Depending on the exact population, the house wrens' clutch is usually between two and eight red-blotched cream-white eggs,[19] weighing about 1.4 g (0.05 oz) each and measuring c.17 and 13.4 mm (0.67 and 0.53 in) at the widest points. Only the female incubates these, for around 12–19 days,[19] and she will every now and then leave the nest for various reasons. While she is on the nest, the male provisions her with food. The young, which like all passerines hatch almost naked and helpless, take another 15–19 days or so to fledge[20]. They are being fed by both parents, and need plenty of food given their tiny size (see also Bergmann's Rule). As the young near fledging, the parents spend much of their time procuring food for them. Brood loss due to predation was found to be light in the Southern Andean Yungas, with predation of nestling young being almost insignificant.[21] Known predators of house wrens at the nest include cats, rats, opossums, woodpeckers, foxes, raccoons, squirrels, snakes and owls. Adults away from the nests can usually avoid these predators although both small hawks and owls occasionally take free-flying adult wrens.[22]
Migrant populations are nesting within 6 weeks of returning from winter quarters, leaving theoretically time for a second brood.[12][23] In the subtropical montane forest of northwestern Argentina and similar habitat, the southern house wren breeds in the rainy summer months from late October to late December.[21]
In Washington, D.C. area, house wren parents made significantly more feeding trips per hour in suburban backyards compared to rural backyards. Yet rural nestlings grew at a faster rate than their suburban counterparts. In addition, suburban parents spent less time brooding (sitting on the nest) compared to rural parents. Such results suggest that suburban backyard habitats offer house wrens food for nestlings that is inferior in either quality or quantity to what rural habitats offer. Food items may, for example, be smaller in suburban habitats, and force adults to make more trips to the box.[24]
In South Temperate Argentina, southern house wrens dispersed more frequently between-seasons than within a season, with females dispersing more often than males. Widowed and single males dispersed more frequently than paired males, whilst within-season divorce increased the breeding success of females but not males.[25]
The house wren may have been displaced somewhat in some northern parts of its range by the introduction of the house sparrow, but is still common and widespread throughout most of the Americas. It is not considered threatened by the IUCN,[1] though this would certainly not hold true for several of the island population if they turn out to be true species.
Some taxa, especially from the Lesser Antilles, are rare and highly endangered or possibly already extinct. Several factors seem to have contributed to a varying degree to the decline of these birds, namely habitat destruction, predation by introduced mongooses, and hurricanes:
The Saint Vincent house wren (Troglodytes aedon musicus) of Saint Vincent was close to extinction in the mid-late 20th century; it has since recovered and today is not uncommon.[8]
As remarked above, these are variously placed in T. musculus if that is considered distinct, or as one or several distinct species.
John James Audubon illustrates the house wren in Birds of America (published, London 1827–38) as Plate 83. The image was engraved and colored by the Robert Havell, London workshops. The limited 1985 edition by Audubon is available for purchase at the New York History Society.[26]
Troglodytes Aedon was one of the two pets of King Friday the XIII in Mister Rogers' Neighborhood. Trog, as the King called him, was a wooden wren on a stick, and Trog had his own song. King Friday's other pet was a mockingbird (a wooden mockingbird on a stick) named Mimus Polyglottos (see Neighborhood of Make-Believe).
Brazilian footballer Garrincha earned his nickname from one of the names the house wren has in Rio de Janeiro.[27]
The house wren (Troglodytes aedon) is a very small bird of the wren family, Troglodytidae. It occurs from Canada to southernmost South America, and is thus the most widely distributed native bird in the Americas. It occurs in most suburban areas in its range and it is the single most common wren. Its taxonomy is highly complex and some subspecies groups are often considered separate species. The name troglodytes means "hole dweller", and is a reference to the bird's tendency to disappear into crevices when hunting insects or to seek shelter.