Carolina Wren

The Carolina wren was first described under the name of Sylvia ludoviciana by John Latham in 1790. in 1788.|group="note"}} Louis Pierre Vieillot considered all wrens under the genus Troglodytes and called the Carolina wren Troglodytes arundinaceus, but placed it subsequently in a separate genus Thryothorus (initially misspelled Thriothorus)

The genus name Thryothorus is of Greek origin from the combination of the noun θρύον : thrýon ("rush, reed") and the adjective θοῦρος : thoũros ("rushing, impetuous"; derivative of verb θρῴσκειν : thrōskein to leap up, spring, jump at). Thus, Thryothorus means 'reed jumper'. Its specific name ludovicianus is a post-classical Latin term for Ludovicus (derivative from Louis XIV) that means 'of Louisiana' that identifies the locality of the specimen collected near New Orleans.

Thryothorus used to be the largest genus in the family Troglodytidae, with 27 species, but molecular phylogenetic studies revealed that it represented a polyphyletic assemblage of at least four independent clades now recognized at the genus level. The Carolina wren is now the only species within this genus. The seven recognized subspecies of the Carolina wren are: *T. l. ludovicianus (Latham, 1790) – southeast Canada (southern Ontario, irregularly in eastern and southern Quebec) and the eastern United States (southern Wisconsin and New England southward to Texas and northern Florida) *T. l. miamensis Florida wren (Ridgway, 1875) – Florida from approximately 30°N (Gainesville) region southward through the rest of the state *T. l. nesophilus Dog Island wren (Stevenson, 1973) – Dog Island in northwestern Florida *T. l. burleighi – Burleigh's Carolina wren (Lowery, 1940) Offshore islands off of the Mississippi coast: Cat Island, Ship Island (Mississippi), and Horn Island *T. l. lomitensis – Lomita wren (Sennett, 1890) southern Texas to the extreme northeast of Mexico (Tamaulipas) *T. l. berlandieri – Berlandier's wren (S. F. Baird, 1858) - northeastern Mexico (eastern Coahuila, Nuevo León, and southwestern Tamaulipas) *T. l. tropicalis – northeastern Mexico (eastern San Luis Potosí and southern Tamaulipas) *T. ludovicianus is traditionally placed within its own genus as its only representative of North America, but recent DNA work suggests it is closely allied with the Bewick's wren. A distinct population in the Yucatán Peninsula of Mexico, Belize, Nicaragua, and in Guatemala is treated as a separate species, either known as Cabot's wren or white-browed wren (Thryothorus albinucha). It is considered a subspecies of T. ludovicianus by some authors, however. |2= }} }} |2= }} |2= |2=Uropsila leucogastra }} |2=Cyphorhinus arada }} |2= }} |2=Thryothorus sinaloa }} }} }} }}

The juvenile T.l. ludovicianus is similar in appearance, but the plumage is generally paler; a softer texture, buff-tipped wing coverts, and a paler superciliary streak. In August and September, the partial plumage molt for the post-juvenile wrens is darker in color and affects the contour plumage, wing coverts, tail and develops a whiter superciliary stripe. The post-nuptial molt for adults in the same time period is more pronounced in color than the spring molt, with both sexes similar in appearance.

Survival rates differ by region. A male captured in Arkansas lived to be at least 73 months old, and in Alabama, the oldest female and male captured were six and ten years old, respectively. In a survival probability mark-and-recapture study conducted within the Southeastern United States from 1992 to 2003, roughly 90 percent of the banded wrens died within 10 years.

The easiest species to confuse with the Carolina wren is Bewick's wren, which differs in being smaller but with a longer tail, grayer-brown above and whiter below. The Carolina and white-browed wrens differ from the house wren in being larger, with a decidedly longer bill and hind toe; their culmen has a notch behind the tip.

These birds are largely resident, and will only disperse beyond their range after mild winters. In certain parts of their range, such as most of Iowa, prolonged periods of snow can curtail potential expansion. Permanent breeding locations range from eastern Nebraska, southern Michigan, southeast Ontario and the New England states to Mexican states such as Coahuila, Nuevo León, San Luis Potosí and Tamaulipas and the Gulf Coast of the United States. Carolina wrens adapt to various habitats. Natural habitats include various types of woodland such as oak hardwoods and mixed oak-pine woodlands, ash and elmwoods, hickory-oak woodlands with a healthy amount of tangled undergrowth. The preferred habitats are riparian forest, brushy edges, swamps, overgrown farmland, and suburban yards with abundant thick shrubs and trees, and parks. It has an affinity for dilapidated buildings and unkempt yards in man-made areas. Subspecies burleighi and neophilus inhabit slash pine and palmettos.

===Song and calls=== Carolina wrens sing year round and at any point during the daytime, with the exception of performing during the most harsh weather conditions. One of these patterns is repeated for several minutes, and although the male's song can be repeated up to twelve times, the general number of songs range from three to five times in repetition. While singing, the tail of the birds is pointed downward. Some general vocalizations have been transcribed as teakettle-teakettle-teakettle and cheery-cheery-cheery. Female Carolina wrens possess song control regions that would appear to make them capable of singing with repertoires like the male. Due to vocalizations that they occasionally make with the male, it has been suggested that song perception plays a role and is of behavioral relevance. Different subspecies have variations in songs and calls, such as miamensis having a more rapid song that contains more notes than the races that are further north. Their songs can be confused with the Kentucky warbler. The song patterns are similar, but the warbler's songs are described as richer, with more ringing and a hurried pace. Other bird species with songs described as akin to the wren are the flicker, Baltimore oriole, grey catbird, and more specifically the peto, peto, peto call of the tufted titmouse and the whistle of the northern cardinal. Occasionally, the wrens mimic other species; in Pennsylvania this trait has caused the bird to be also known as the 'mocking wren'.

A 2006 study suggested that the correlation of tail length and body size in males, wing length in females, and lifespan for both sexes were signs of individual quality, and the wrens of high quality tend to mate with like individuals. The courting and antagonistic encounters that involve the tail fanning and wing drooping was suggested to be a possible signaling use. Age and life experience are not thought of as significant for potential mates due to their relatively short lifespan and sedentary lifestyle. Due to the large size of male wrens and the male's vigor in defending its territory, intrasexual selection was given as a possible explanation for the sexual dimorphism.

Both sexes are involved in defending the territory. One aspect of territorial defense involves identifying the proximity of the threat based on the loudness of bird song as well as the level of degradation of the calls. In experiments involving playback, the wrens are capable of discriminating between degraded and undegraded songs, as well as degraded songs in the same acoustic conditions, and can detect changes of acoustic properties within their territories, such as songs under foliage. Song degradation can also be used to determine the proximity of potential intruders. If the song of a bird appears to be degraded, the wrens will assume that the threat is distant and not respond; if the song is not degraded, they respond by attacking. Not all birds within their territory are potential enemies. Some species of birds that are neighbors are designated as dear enemies by the wrens, and the responses to neighbors and intruders in their territories differ by the season. In spring, the wrens respond more aggressively toward neighbors, though in the fall, no major discrepancy in responses is shown. When protecting their nest, alarm calls are the general response. The wrens judge the size of the potential threat, such as a blue jay and avoid the risk of injury when attacking. Countersinging produced by intruder birds is more likely to be taken as an aggressive threat to male Carolina wrens. Both males and females utilize calls in alarm situations, especially in territorial disputes and encounters with predators. Males alone produce the cheer call, which can sound indistinct. In southern regions of their range, the sound males use in alarm disputes is a ringing pink or p'dink sound. Females are the only ones that can perform the paired dit-dit or chatter sounds. The former can be used in territorial disputes with predators, and with at least northern populations the songs are used in alternation with the males cheer chant. The chatter is used exclusively with territorial encounters with male song, and the song can either follow or overlap her mate's song.

Carolina wrens spend the majority of their time on or near the ground searching for food, or in tangles of vegetation and vines. They also probe bark crevices on lower tree levels, or pick up leaf-litter in order to search for prey. Their diet consists of invertebrates, such as beetles, true bugs, grasshoppers, katydids, spiders, ants, bees, and wasps. Small lizards and tree frogs also make up the carnivorous portion of their diet. Vegetable matter, such as fruit pulp and various seeds, makes up a small percentage of their diet. In the northern portion of their range, they frequent bird feeders.

Carolina wrens are wary, and are more often heard than seen. When on the ground, they move in jerky hops pillaging through various objects, whether man-made or natural. When stationary, they move in twitched motions, jerking their breast around. The wrens also displays a skittish behavior when encountered by humans, as they can be seen thrusting off into cover slowly if approaching is detected. However, they occasionally seek out humans that are near, so long as there is no movement from them.

Carolina wrens are both genetically and socially monogamous and will usually mate for life. Mate changing is rare, Along with thermoregulatory benefits, roosting is thought to reinforce pair-bonding and prevent divorce between mates. The nests are arch-shaped structures with a side entrance and built of dried plants or strips of bark, as well as horsehair, string, wool and snake sloughs. The male obtains nesting materials while the female remains at the site to construct the nest. Nests are located in fragmented or complete cavities in trees, or in man-made structures such as bird-boxes, buildings, tin cans, mailboxes or unorthodox places such as pockets of hanging jackets in sheds or in a tractor in everyday use.

Although Carolina wrens are fairly common, brood parasitism by the brown-headed cowbird is common, with up to 25% of Carolina wren nests being affected in certain regions such as Oklahoma and Alabama. The rate of brood parasitism is thought to be lower in more natural and concealed nesting locations. Fellow species of wren such as Bewick's wren and the winter wren compete for nesting locations and food, respectively. Exposure, and prolonged periods of cold, ice, and snow is thought to affect the wren nestling and adult populations, respectively. Raccoons and black rat snakes also feed on wren eggs and nestlings.

In 1930, the South Carolina Federated Women's club adopted the Carolina wren as the unofficial state bird over the eastern mourning dove and pushed for its official state adoption until 1939, when the South Carolina Legislature named the northern mockingbird as the state bird. In 1948, the legislature repealed their previous decision, and the wren became the official state bird. In 2000, the Carolina wren was featured on the back of the South Carolina edition of the 50 State Quarters.