Carolina wren

{{short description|Species of bird}} {{Good article}} {{Use American English|date=April 2026}} {{Speciesbox | name = Carolina wren | image = Carolina wren (14391).jpg | image_caption = Prospect Park, Brooklyn | image2 = Thryothorus ludovicianus song.ogg | image2_caption = Recorded in [[Cape May, New Jersey]], US | status = LC | status_system = IUCN3.1 | status_ref = <ref name=iucn>{{cite iucn |author=BirdLife International |year=2021 |title=''Thryothorus ludovicianus'' |article-number=e.T103887192A139754660 |doi=10.2305/IUCN.UK.2021-3.RLTS.T103887192A139754660.en}}</ref> | genus = Thryothorus | parent_authority = [[Louis Pierre Vieillot|Vieillot]], 1816<ref name=David/> | species = ludovicianus | authority = ([[John Latham (ornithologist)|Latham]], 1790) | subdivision_ranks = Subspecies | subdivision_ref = <ref name="IOC"/><ref name=avilist/> | subdivision = {{collapsible list|bullets = true|title=<small>List</small> |''T. l. albinucha'' |''T. l. berlandieri'' |''T. l. burleighi'' |''T. l. lomitensis'' |''T. l. ludovicianus'' |''T. l. miamensis'' |''T. l. nesophilus'' |''T. l. oberholseri'' |''T. l. tropicalis'' |''T. l. subfulvus''}} | range_map = Thryothorus ludovicianus species distribution map.svg | range_map_caption = Range of the Carolina wren (''T. ludovicianus'') | synonyms = ''Sylvia ludoviciana'' <small>(Latham, 1790)</small> | synonyms_ref = <ref>{{cite book|title=Check-list of birds of the World. Volume IX.|editor=Mayr, E.|editor2=Greenway, J.C. Jr.|year=1960|publisher=Museum of Comparative Zoology|place=Cambridge, Mass. |url=https://archive.org/stream/checklistofbirds91960pete#page/408/mode/2up|pages=409–410}}</ref> }} [[File:Carolina wren (Thryothorus ludovicianus).webm| thumb|''Thryothorus ludovicianus'']] The '''Carolina wren''' ('''''Thryothorus ludovicianus''''') is a species of [[wren]] common in the eastern United States, the extreme south of Ontario, Canada, the northeast and southeast of Mexico, and into northern Central America. Severe winters restrict the northern limits of their range, while favorable weather conditions lead to a northward extension of their breeding range. Their preferred habitat is in dense cover in forest, farm edges, and suburban areas. This wren is the [[List of U.S. state birds|state bird]] of South Carolina.

Ten [[subspecies]] are recognized, occurring across the range of the species; they differ slightly in song and appearance. It is generally inconspicuous, avoiding the open for extended periods of time. When out in the open, they energetically investigate their surroundings and are rarely stationary. After finding a mate, pairs maintain a [[territory (animal)|territory]] and stay together for several years. Both males and females give out alarm calls, but only males sing to advertise territory. Carolina wrens raise multiple broods during the summer breeding season but can fall victim to [[brood parasitism]] by [[brown-headed cowbird]]s, among other species.

==Taxonomy== The Carolina wren was first described under the name of ''Sylvia ludoviciana'' by [[John Latham (ornithologist)|John Latham]] in 1790.<ref name="Brewer15">{{cite book|last=Brewer|first=David|title=Wrens, Dippers, and Thrashers|publisher=Yale University Press|year=2001|pages=132–4|url=https://books.google.com/books?id=-r35SXfm9BYC&pg=PA134|isbn=978-0-300-09059-8}}</ref>{{#tag:ref|Johann Friedrich Gmelin wrongly associated the Carolina wren with the European wrens under the name ''Motacilla troglodytes'' (originally coined by [[Carl Linnaeus]] in [[Systema Naturae]])<ref>{{cite book|last=Linnaeus|first=C.|author-link=Carl Linnaeus|title=Systema Naturae per Regna Tria Naturae, Secundum Classes, Ordines, Genera, Species, cum Characteribus, Differentiis, Synonymis, Locis. Tomus I. Editio Decima, Reformata|volume=v.1| publisher=Laurentius Salvius|location=[[Stockholm|Holmiae]]|language=la| year=1758|page=188|url=https://www.biodiversitylibrary.org/page/727076#page/208/mode/1up}}</ref> in 1788.<ref name="Brewer15"/><ref>{{cite book|last=Harding|first=J.|title=Journal of the Academy of the Sciences of Philadelphia: Volume IV, Part I| publisher=[[Academy of Natural Sciences of Drexel University|Academy of Sciences of Philadelphia]]|location=[[Philadelphia]]|year=1824|pages=28–29|url=https://archive.org/stream/journalofacademy04acaduoft#page/28/mode/2up}}</ref>|group="note"}} [[Louis Pierre Vieillot]] at first considered all wrens under the genus [[Troglodytes (bird)|''Troglodytes'']] and called the Carolina wren ''Troglodytes arundinaceus'', but subsequently placed it in a separate genus ''Thryothorus'' (initially misspelled ''Thriothorus'')<ref name=David /> that he created in 1816.<ref>{{cite journal|journal=Auk|title=A synopsis of the genus commonly called Anorthura|author=Oberholser, Harry C.|year=1902|pages=175–181|url=https://archive.org/stream/jstor-4069309/4069309#page/n1/mode/2up|jstor=4069309|volume=19|issue=2|doi=10.2307/4069309}}</ref>

===Etymology=== The genus name ''Thryothorus'' is of [[Ancient Greek|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'.<ref>{{cite book | last=Jobling | first=James A. | year=2010| title=The Helm Dictionary of Scientific Bird Names | publisher=Christopher Helm | location=London | isbn=978-1-4081-2501-4 | page=385 | url=https://archive.org/details/Helm_Dictionary_of_Scientific_Bird_Names_by_James_A._Jobling/page/n385 }}</ref>

Its [[specific name (zoology)|specific name]] ''ludovicianus'' is a post-classical [[Latin]] term for ''Ludovicus'' (derivative from [[Louis XIV]]) meaning 'of [[Louisiana (New France)|Louisiana]]' that identifies the locality of the specimen collected near [[New Orleans]].<ref name="Sandrock">{{cite book|last=Sandrock|first=James|title=The Scientific Nomenclature of Birds in the Upper Midwest|publisher=University of Iowa Press|year=2014|page=144|url=https://books.google.com/books?id=_I3zAgAAQBAJ&pg=PA144|isbn=978-1-60938-225-4}}</ref><ref>{{cite book|url=https://archive.org/stream/coueschecklistof00couerich#page/31/mode/1up|page=31|title=Coues check list of North American Birds|edition=2nd|year=1882|author=Coues, Elliot|publisher=Estes and Lauriat|place=Boston}}</ref>

==Species== ''Thryothorus'' used to be considered 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 [[clade]]s now recognized at generic level, with the other 26 species split off in the genera ''[[Cantorchilus]]'', ''[[Pheugopedius]]'', and ''[[Thryophilus]]''.<ref name=Mann/><ref>{{cite journal |last1=Esteban Lara |first1=Carlos |last2=Cuervo |first2=Andrés M. |last3=Valderrama |first3=Sandra V. |last4=Calderón-F. |first4=Diego |last5=Cadena |first5=Carlos Daniel |title=A New Species of Wren (Troglodytidae: thryophilus) from the Dry Cauca River Canyon, Northwestern Colombia |journal=The Auk |date=2012 |issue=129 |page=537}}</ref> The Carolina wren is now the only species within this genus;<ref name="IOC">{{cite web |title=Dapple-throats, sugarbirds, fairy-bluebirds, kinglets, Elachura, hyliotas, wrens, gnatcatchers – IOC World Bird List |website=IOC World Bird List – Version 15.2 |date=2026-04-13 |url=https://www.worldbirdnames.org/new/bow/sugarbirds/ |access-date=2026-04-30}}</ref><ref name=avilist>{{ cite web | author=AviList Core Team | date=2025 | title=AviList: The Global Avian Checklist, v2025 | doi=10.2173/avilist.v2025 | doi-access=free | url=http://www.avilist.org/checklist/v2025/ | access-date=2026-04-30 }}</ref> DNA work suggests it is most closely allied to [[Bewick's wren]] ''Thryomanes bewickii''.<ref name=Mann/>

===Subspecies=== Ten subspecies of the Carolina wren are currently recognized:<ref name="IOC"/><ref name=avilist/>

*''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'' (Ridgway, 1875) – "Florida wren"; Florida peninsula from approximately 30°N ([[Gainesville, Florida|Gainesville]]) region southward through the rest of the state *''T. l. nesophilus'' (Stevenson, 1973) – "Dog Island wren"; [[Dog Island (Florida)|Dog Island]] in northwestern Florida *''T. l. burleighi'' (Lowery, 1940) – "Burleigh's Carolina wren"; islands off of the Mississippi coast, on [[Cat Island (Mississippi)|Cat Island]], [[Ship Island]], and [[Horn Island (Mississippi)|Horn Island]] *''T. l. lomitensis'' (Sennett, 1890) – "Lomita wren"; southern Texas (lower Rio Grande Valley) to the extreme northeast of Mexico ([[Tamaulipas]]) *''T. l. oberholseri'' Lowery, 1940 – southwestern Texas (south-central USA) and northern Mexico *''T. l. berlandieri'' (S. F. Baird, 1858) – "Berlandier's wren"; tropical northeastern Mexico (eastern [[Coahuila]], [[Nuevo León]], and southwestern Tamaulipas) *''T. l. tropicalis'' Lowery & Newman, 1949 – northeastern Mexico (eastern [[San Luis Potosí]] and southern Tamaulipas) *''T. l. albinucha'' (Cabot, 1847) – southeastern Mexico (Yucatan Peninsula) to northern Guatemala (Petén) *''T. l. subfulvus'' Miller & Griscom, 1925 – arid interior of Guatemala to northwestern Nicaragua

The last two subspecies above, forming a disjunct population in the [[Yucatán Peninsula]] of Mexico, Belize, Nicaragua, and in Guatemala, are sometimes treated as a separate species, either known as Cabot's wren or white-browed wren (''Thryothorus albinucha'').<ref name="Brewer15"/><ref name="TAMU"/> They are included in ''T. ludovicianus'' by most authors, however.<ref name="IOC"/><ref name=avilist/><ref name="Carolina or White-browed Wren">{{cite web|title=Carolina or White-browed Wren (Thryothorus [ludovicianus or albinucha])|url=http://avibase.bsc-eoc.org/species.jsp?lang=EN&avibaseid=CB5469E1211E7EFF|publisher=AviBase|access-date=16 February 2015}}</ref>

Relationships of the Carolina wren to selected other wrens:{{citation needed|date=April 2026|reason=Source needed; does not match Brewer ref fully}} {{clade| style=font-size:95%; line-height:95% |1={{clade |1={{clade |1={{clade |1=''[[Grey-barred wren|Campylorhynchus megalopterus]]'' |2=''[[Cactus wren|Campylorhynchus brunneicapillus]]'' }} |2={{clade |1=''[[Bewick's wren|Thryomanes bewicki]]'' |2={{clade |1='''''Thryothorus ludovicianus ludovicianus''''' |2='''''T. l. albinucha''''' }} }} }} |2={{clade |1={{clade |1=''[[Peruvian wren|Cinnycerthia peruana]]'' |2={{clade |1=''[[Fawn-breasted wren|Thryothorus guarayanus]]'' |2=''[[Buff-breasted wren|Thryothorus leucotis]]'' }} }} |2={{clade |1={{clade |1={{clade |1={{clade |1={{clade |1=''[[White-breasted wood wren|Henicorhina leucosticta]]'' |2=''[[Grey-breasted wood wren|Henicorhina leucophrys]]'' }} |2=''[[White-bellied wren|Uropsila leucogastra]]'' }} |2=''[[Musician wren|Cyphorhinus arada]]'' }} |2={{clade |1=''[[Spot-breasted wren|Thryothorus maculipectus]]'' |2=''[[Coraya wren|Thryothorus coraya]]'' }} }} |2=''[[Sinaloa wren|Thryothorus sinaloa]]'' }} }} }} }}

==Description== [[File:CarolinaWren-23SEP2016.jpg|alt=Carolina Wren|left|thumb|335x335px|Carolina wren in [[Greenville, South Carolina]] ]] At {{convert|12.5|to|14|cm|in|abbr=on}} long, with a {{convert|29|cm|in|abbr=on}} wingspan and a weight of about {{convert|18|to|23|g|oz|abbr=on}}, the Carolina wren is a fairly large wren; the second largest in the United States species after the [[cactus wren]]. Among standard measurements, the [[Wing chord (biology)|wing chord]] is {{convert|5.4|to|6.4|cm|in|abbr=on}}, the [[tail]] is {{convert|4.5|to|5.6|cm|in|abbr=on}}, the [[Culmen (bird)|culmen]] is {{convert|1.4|to|1.8|cm|in|abbr=on}} and the [[Tarsus (skeleton)|tarsus]] is {{convert|2|to|2.3|cm|in|abbr=on}}.<ref name="Brewer15"/> [[Sexual dimorphism]] is slight with males being larger than their mates. A study indicated that of 42 mated pairs, every male but one was larger than the female of the pair. The males were on average 11 percent heavier along with having longer wing chords.<ref name="Haggerty">{{cite journal|author=Haggerty, Thomas M.|year=2006|title=Sexual size dimorphism and assortative mating in Carolina Wrens|journal=Journal of Field Ornithology|volume=77|issue=3|pages=259–65|url=http://www.buildingthepride.com/faculty/tmhaggerty/Articles/dimorphism%20article.pdf|doi=10.1111/j.1557-9263.2006.00051.x}}</ref> For ''T. l. ludovicianus'', the [[crown (anatomy)|crown]] is rich brown that appears more chestnut-colored on its [[rump (animal)|rump]] and upper tail coverts. Shoulders and greater [[covert feathers|coverts]] are a rich brown, with a series of small white dots on the lesser primary coverts. The secondary coverts are rich brown with a darker brown barring on both webs; the bars on the primaries are on the outerwebs only, but darker and more noticeable. The [[flight feathers|rectrices]] are brown with 18 to 20 bars that span across the tail. The white [[supercilium|supercilious streak]] borders thinly with a black above and below, and extends above and beyond its shoulders. The ear coverts are speckled gray and grayish-black. Its chin and throat are grey that becomes buff on its chest, flank and belly, though the latter two are of a warmer color. The underwing coverts sport a grayish buff color. Its [[iris (anatomy)|iris]] is reddish-brown, the [[upper mandible]] is dark gray to pinkish-gray, paler at the base and on the [[lower mandible]]. The legs are light pinkish to yellowish-brown color.<ref name="Brewer15"/>

Several differences are seen among the subspecies. In contrast to ''T. l. ludovicianus'', ''T. l. berlandieri'' is of a slightly smaller build, but possesses a larger bill, the upperparts are duller brown with deeper colored underparts, ''T. l. lomitensis'' is of a duller color (than either ''T. l. ludovicianus'' or ''T. l. berlandieri'') with its underparts either pale or almost white, ''T. l. miamensis'' contains darker rusty chestnut upperparts and deeper colored below. ''T. l. burleighi'' is duller and sootier with less distinct tail markings, ''T. l. mesophilus'' has paler underparts and a whiter supercilium, and ''T. l. tropicalis'' is darker than all races, and contains heavier bars than ''T. l. berlandieri''.<ref name="Brewer15"/>

===Plumage=== Juvenile ''T. l. ludovicianus'' is similar in appearance to the adult, but the plumage is generally paler; a softer texture, buff-tipped wing coverts, and a paler superciliary streak.<ref name="Brewer15"/><ref name="Bent"/> 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.<ref name="Bent"/>

===Life span=== [[File:Thryothorus heads.jpg|thumb|right|285px|Sketches of ''Thryothorus ludovicianus'', ''T. l. lomitensis'', and ''Thryomanes bewickii'' (Bewick's wren) and one of its subspecies]] Survival rates differ by region. A male captured in Arkansas lived to be at least 6 years and 1 month old, and in Alabama, the oldest female and male captured were six and ten years old, respectively. In a survival probability [[Mark and recapture|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.<ref name="Demography and Populations"/>

===Similar species=== The easiest species to confuse with the Carolina wren is Bewick's wren,<ref name=Martinez/> 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 [[Northern house wren|house wren]] in being larger, with a much more obvious supercilium, a decidedly longer [[beak|bill]] and hind toe; and the [[Culmen (bird)|culmen]] has a notch behind the tip.<ref name=Brattstrom/>

==Habitat and distribution== [[File:Carolina Wren (4249754138).jpg|thumb|Carolina wren at feeder]] These birds are largely resident, and will only disperse beyond their range after mild winters.<ref name="Brewer15"/> Carolina wrens sporadically breed as far north as Maine and Quebec after mild winters.<ref name="Brewer15"/><ref name="NatGeo">{{cite book|last1=Dunn|first1=John Lloyd|last2=Alderfer|first2=Jonathan K.|title=National Geographic Illustrated Birds of North America|publisher=National Geographic Books|year=2004|page=342|url=https://books.google.com/books?id=1VsvhUl1dyEC&pg=PT343|isbn=978-1-4262-0525-5}}</ref> In certain parts of their range, such as most of Iowa, prolonged periods of snow can curtail potential expansion.<ref name="Jackson">{{cite book|last=Jackson|first=Laura Press|title=The Iowa Breeding Bird Atlas|publisher=University of Iowa Press|year=1996|pages=266–7|url=https://books.google.com/books?id=igp_WugmoX8C&pg=PA266|isbn=978-1-4262-0525-5}}</ref> 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]].<ref name="Demography and Populations"/> Local occurrences with infrequent and likely breeding locations include southeast South Dakota, central Kansas, eastern Colorado, western Oklahoma and Texas as far as Maine and New Brunswick]].<ref name="Demography and Populations"/> There have been occasional vagrants spotted in Colorado, New Mexico]], and Arizona, Wyoming, South Dakota, Manitoba, Nova Scotia, and the [[Gulf of St. Lawrence]].<ref name="Brewer15"/><ref name="NatGeo"/>

The range of the wrens increased northward and westward in several regions over the past few centuries. In Massachusetts, the wrens had expanded westward and northeastward from its former southeastern location in approximately 35 years, in New York the population increased three-fold in roughly 25 years, while in the midwest states of Ohio and Michigan, numbers have increased since the mid-1800s and early 1900s, respectively.<ref name="Demography and Populations"/> Expansion around Ontario occurred since early reports in 1890 and 1905. Explanations given include infrequent winter storms in the 20th century, expanded forest habitats, and the wrens taking advantage of urban areas containing feeders, especially in winter.<ref name="Demography and Populations"/> From 1966 to 2015 the Carolina wren experienced a greater than 1.5% annual population increase throughout most of its northern range, extending from southern Maine to southern Nebraska.<ref>{{cite web |title=Carolina Wren Thryothorus ludovicianus BBS Trend Map, 1966 - 2015 |url=https://www.mbr-pwrc.usgs.gov/bbs/tr2015/trend2015_v3.html |website=USGS |publisher=U.S. Department of the Interior |access-date=2020-12-09}}</ref>

Carolina wrens adapt to various habitats. Natural habitats include various types of woodland such as [[oak]] hardwoods and mixed oak-pine woodlands, [[ash tree|ash]] and [[elm tree|elmwoods]], hickory-oak woodlands with a healthy amount of tangled undergrowth.<ref name="Brewer15"/><ref name="Dunne"/> The preferred habitats are [[riparian forest]], [[shrubland|brushy edges]], [[swamp]]s, overgrown [[farmland]], and suburban yards with abundant thick shrubs and trees, and parks.<ref name="Brewer15"/><ref name="Dunne"/> It has an affinity for dilapidated buildings and unkempt yards in man-made areas.<ref name="Dunne"/> Subspecies ''T. l. burleighi'' and ''T. l. neophilus'' inhabit [[slash pine]] and [[Sabal|palmettos]].<ref name="Brewer15"/><ref name="Dunne"/>

==Behavior==

===Song and calls=== [[File:Carolina Wren, Forsyth, Georgia.ogg|right|thumb|Singing of Carolina wren (''Thryothorus ludovicianus'')]] [[File:Carolina Wren.ogg|right|thumb|Carolina Wren, Wilkes County, NC.]] [[File:Carolina Wren Singing.jpg|alt=A Carolina Wren singing in Forest Park.|left|thumb|A Carolina Wren singing in Forest Park.]] Carolina wrens sing year round and at any point during the daytime, except during the most harsh weather conditions.<ref name="Dunne"/> Males alone sing, and have a repertoire of at least twenty different phrase patterns and on average, thirty two.<ref name="Nealen00">{{cite journal|author1=Nealen, Paul M. |author2=Perkel, David J. |year=2000|title=Sexual Dimorphism in the Song System of the Carolina Wren (''Thryothorus ludovicianus'')|journal=The Journal of Comparative Neurology|volume=418|issue=4|pages=346–360|pmid=10701831|doi=10.1002/(sici)1096-9861(20000313)418:3<346::aid-cne8>3.3.co;2-b }}</ref><ref name="Elliott2">{{cite book|last=Elliott|first=Lang|title=Music of the Birds: A Celebration of Bird Song|publisher= Houghton Mifflin Harcourt|year=1999|page=[https://archive.org/details/musicofbirdscele0000elli/page/30 30]|url=https://archive.org/details/musicofbirdscele0000elli|url-access=registration|isbn=978-0-618-00697-7}}</ref> 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 ranges 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''.<ref name="Bent"/><ref name="Dunne"/> Various descriptions of the ''teakettle'' song include ''whee-udel, whee-udel, whee-udel'', ''che-wortel, che-wortel'' and ''túrtee-túrtee-túrtee'' and familiar names and phrases such as ''sweet heart, sweet heart'', ''come to me, come to me'', ''sweet William'', and [[Cardinal Richelieu|''Richelieu, Richelieu'']].<ref name="Bent"/>

Males are capable of increasing their repertoire through song learning, but due to their sedentary nature and territorial defense habits, the song learning must occur within the first three months of life.<ref name="Morton87"/> Geographic barriers affect song repertoire size from male wrens, as one study indicated that distances separated as close as {{convert|3|km|sp=us}} by water barriers can have the same effect as that of a distance of {{convert|145|km|sp=us}} in the mainland with no barriers.<ref name="Morton87">{{cite journal|author=Morton, Eugene S.|year=2005|title=The Effects of Distance and Isolation on Song-type Sharing in the Carolina Wren|journal=Wilson Bulletin|volume=99|issue=4|pages=601–10|url=https://sora.unm.edu/sites/default/files/journals/wilson/v099n04/p0601-p0610.pdf}}</ref>

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.<ref name="Nealen00"/>

[[File:Carolina Wren (7318066894).jpg|thumb|right|Carolina wren on Rutland Township Forest Preserve]] 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.<ref name="Brewer15"/>

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.<ref name="Dunne"/> Other bird species with songs described as akin to the wren are the [[Colaptes|flicker]], [[Baltimore oriole]], [[grey catbird]], and more specifically the ''peto, peto, peto'' call of the [[tufted titmouse]] and the whistle of the [[northern cardinal]].<ref name="Bent"/> Occasionally, the wrens mimic other species; in Pennsylvania this trait has caused the bird to be also known as the 'mocking wren'.<ref name="Brewer15"/>

===Sexual selection=== 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.<ref name="Haggerty"/>

===Territorial and predator defense=== 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.<ref name="Naguib95">{{cite journal|author=Naguib, Marc|year=1995|title=Ranging by Song in Carolina Wrens (''Thryothorus ludovicianus''): Effects of Environmental Acoustics and Strength of Song Degradation|journal=Behaviour|volume=133|issue=7|pages=541–559|url=http://www.unc.edu/home/rhwiley/pdfs/EnvironAcousticsCW.pdf|doi=10.1163/156853996x00206}}</ref> 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.<ref name="Richards">{{cite journal|author=Richards, Douglas G.|year=1981|title=Estimation of the Distance of Singing Conspecifics by the Carolina Wren|journal=The Auk|volume=98|issue=1|pages=127–33|doi=10.1093/auk/98.1.127|url=http://www.unc.edu/home/rhwiley/pdfs/Richards1981Distance.pdf|jstor=4085615}}</ref> Not all birds within their territory are potential enemies. Some species of birds that are neighbors are designated as [[Dear enemy effect|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.<ref name="Hyman">{{cite journal|author=Hyman, Jeremy|year=2005|title=Seasonal Variation in Response to Neighbors and Strangers by a Territorial Songbird|journal=Ethology|volume=111|issue=10|pages=951–61|url=http://www.unc.edu/~rhwiley/pdfs/Hyman2005.pdf|doi=10.1111/j.1439-0310.2005.01104.x|bibcode=2005Ethol.111..951H }}</ref> 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.<ref name="D'Orazio">{{cite journal|author1=D'Orazio, Kelly |author2=Neudorf, Diane L. H. |year=2008|title=Nest Defense by Carolina Wrens|journal=The Wilson Journal of Ornithology|volume=120|issue=3|pages=467–72|jstor=20456180|doi=10.1676/06-149.1 |s2cid=86300589 }}</ref> Countersinging produced by intruder birds is more likely to be taken as an aggressive threat to male Carolina wrens.<ref name="Hyman2">{{cite journal|author=Hyman, Jeremy|year=2003|title=Countersinging as a signal of aggression in a territorial songbird|journal=Animal Behaviour|volume=65|issue=6|pages=1179–85|url=http://www.unc.edu/home/rhwiley/pdfs/Hyman1.pdf|doi=10.1006/anbe.2003.2175|s2cid=38239656}}</ref>

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.<ref name="Nealen00"/><ref name="Elliott">{{cite book|last=Elliott|first=Lang|title=Know Your Bird Sounds: Songs and calls of yard, garden, and city birds|publisher=Stackpole Books|year=2004|page=29|url=https://books.google.com/books?id=ChyiBZr6GU8C&pg=PA28|isbn=978-0-8117-2963-5}}</ref>

===Feeding=== 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 [[Invertebrate|invertebrates]], such as beetles, [[Hemiptera|true bugs]], [[grasshopper]]s, [[katydid]]s, spiders, ants, bees, and wasps. Small lizards and [[tree frog]]s 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 feeder]]s.<ref name="Brewer15"/><ref name="Dunne"/>

===Movement=== 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.<ref name="Dunne"/> While moving abruptly, they pause momentarily for chattering or singing.<ref name="Bent">{{cite journal|author=Bent, Arthur C.|year=1948|title=Life Histories of North American Nuthatches, Wrens, Thrashers, and their Allies: Order Passeriformes|journal=Bulletin of the United States National Museum|issue=195|pages=205–16|doi=10.5479/si.03629236.195.1|hdl=10088/10012|url=https://digitalcommons.unl.edu/biosciornithology/99 |hdl-access=free}}</ref> When stationary, they move in twitched motions, jerking their breast around.<ref name="Dunne"/> They also sun- or sand-bathe.<ref name="Hauser">{{cite journal|author=Hauser, Doris C.|year=1957|title=Some Obversations of Sun-bathing in Birds|journal=The Wilson Bulletin|volume=69|issue=1|pages=259–65|url=https://sora.unm.edu/sites/default/files/journals/wilson/v069n01/p0078-p0090.pdf}}</ref> The wrens also displays a skittish behavior when encountered by humans, 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.<ref name="Bent"/> Other movements include crawling like a [[Treecreeper|creeper]] and hanging upside-down like a [[nuthatch]].<ref name="Dunne"/>

Flights are generally of short duration, rapid, low-leveled, and wavelike. The wings during flight are flapped rapidly, and are frequently used during foraging. They are also capable of flying vertically from the base of a tree to the top in a single wing assisted bound.<ref name="Brewer15"/><ref name="Dunne">{{cite book|last=Dunne|first=Pete|title=Pete Dunne's Essential Field Guide Companion: A Comprehensive Resource for Identifying North American Birds|publisher=Houghton Mifflin Harcourt|year=2006|page=479|url=https://books.google.com/books?id=ISgKT2ehj7oC&pg=PA511|isbn=978-0-300-09059-8}}</ref>

===Breeding=== [[File:Carolina Wren nesting in a duck box - Flickr - Andrea Westmoreland.jpg|thumb|Carolina wren nesting in a duck nestbox]] Carolina wrens are both genetically and socially [[monogamy in animals|monogamous]] and will usually mate for life. Mate changing is rare,<ref name="Haggerty"/> and there has been one possible observation of polygamy.<ref name="Brewer15"/> During the winter season, males are more responsible for guarding the territory. Females vary in succeeding to maintain winter territories without a mate.<ref name="Brewer15"/> It has been suggested that the possibility of desertion and decline in care-taking from males along with the need for security in resources year-round prevent extra pair copulations from females, as the mortality rate for Carolina wrens peaks during the winter.<ref name="Haggerty&Morton">{{cite journal|author1=Haggerty, Thomas M. |author2=Morton, Eugene M. |author3=Fleischer, Robert C. |year=2001|title=Genetic Monogamy in Carolina Wrens (''Thryothorus ludovicianus'')|jstor=4089770|journal=The Auk|volume=118|issue=1|pages=215–19|url=https://sora.unm.edu/sites/default/files/journals/auk/v118n01/p00215-p00219.pdf|doi=10.1093/auk/118.1.215|doi-access=free}}</ref> Along with thermoregulatory benefits, [[Bird#Resting and roosting|roosting]] is thought to reinforce pair-bonding and prevent divorce between mates.<ref name="Labinsky">{{cite journal|author1=Labinsky, Ronald F. |author2=Arnett Jr., John E. |year=2006|title=Pair Roosting of Carolina Wrens (''Thryothorus ludovicianus'')|journal=The Wilson Journal of Ornithology|volume=118|issue=4|pages=566–569|doi=10.1676/05-109.1|jstor=20455927|s2cid=86234353 }}</ref>

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.<ref name="Brewer15"/><ref name="Bent"/> Nests are from {{convert|1|-|3|m|ft|abbr=on}} from the ground and are rarely higher. They occasionally can be built in sloping locations or at ground level.<ref name="Brewer15"/>

Egg laying dates and clutch size vary by region; in Texas the time period is from late February to late August, while in Iowa it ranges from late April to June.<ref name="TAMU">{{cite web|title=''Thryothorus ludovicianus''|url=http://txtbba.tamu.edu/species-accounts/carolina-wren/|year=2006|work=Texas A&M AgriLifeExtension|publisher=Texas A&M University|access-date=31 January 2015}}</ref><ref name="Jackson"/> The clutch size is generally three to six eggs, but can reach as high as seven in Texas.<ref name="Brewer15"/><ref name="TAMU"/> The eggs are creamy white with brown or reddish-brown spots, and are more heavily marked at the broad end.<ref name="Brewer15"/> They are incubated by the female for 12–16 days. After the young hatch, they are fed exclusively on invertebrates and fledge in 12–14 days. As many as three broods may be raised by a pair in a single breeding season.<ref name="Brewer15"/> In one study, three of the 70 fledglings remained in or defended territory adjacent to the natal area.<ref name="Demography and Populations"/>

Male and females are involved in the process of provisioning at similar rates throughout most nest stages, with the males providing slightly more in the nestling stages. Both sexes increase their provision rates as the nestlings grow in age.<ref name="Neudorf">{{cite journal|author1=Neudorf, Diane L. H. |author2=Broddick, Mallory J. |author3=Cureton II |author4=James C. |year=2013|title=Parental Provisioning by Carolina Wrens|journal=The Wilson Journal of Ornithology|volume=125|issue=1|pages=179–184|doi=10.1676/12-009.1|s2cid=85033300 }}</ref>

==Predation and threats== 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.<ref name="Brewer15"/><ref name="Demography and Populations"/> Cowbird parasitism peaks in April at 41%, and is as low as 8% and 0% in July and August, respectively. Female cowbirds sometimes eject Carolina wren eggs before laying their own, and even if host eggs are retained, the size of cowbird eggs negatively affect the hatching success of wren eggs. As a result, cowbirds may have a significant impact on the reproductive success of wrens.<ref name="Brewer15"/><ref name="Demography and Populations"/> The feeding rate for cowbird nestlings is higher than wren feeding rates, and some have been raised to independence.<ref name="Demography and Populations"/> This also can be detrimental to the survival of wren nestlings.<ref name="Demography and Populations"/> A rare instance of brood-parasitism by a [[house finch]] has been recorded.<ref name="Demography and Populations"/><ref>{{Cite journal|journal=The Wilson Journal of Ornithology|volume= 118|issue=3|pages=413–415|year=2006|doi=10.1676/05-102.1 |title=Carolina Wren Nest Successfully Parasitized by House Finch |author1=Wood, Douglas R. |author2=William A. Carter|s2cid= 86802925|url= https://www.biodiversitylibrary.org/part/240808}}</ref> The rate of brood parasitism is thought to be lower in more natural and concealed nesting locations.<ref name="Demography and Populations"/> Body parasites such as the larvae of [[blowflies]] feed on nestlings and the blood loss weakens nestlings.<ref name="Demography and Populations">{{cite web|url=https://bna.birds.cornell.edu/bna/species/188/articles/introduction|title=The Birds of North America Online: Carolina Wren}}</ref> Fellow species of wren such as Bewick's wren and the [[winter wren]] compete for nesting locations and food, respectively.<ref name="Demography and Populations"/>

In Virginia, some Carolina wren populations show high levels of [[mercury (element)|mercury]] in their blood and this is acquired from feeding all-year-round on spiders.<ref name="JacksonEvers"/>{{#tag:ref|The [[Holston River|North Folk Holston]] and [[Shenandoah River#South Fork Shenandoah River|South River]]s were used in the study and were both contaminated by industrial activity.|group="note"}} Spiders being at a higher [[trophic level]] contain a higher concentrations of mercury (through [[biomagnification]]) than herbivorous invertebrates. As these wrens are year-round residents, they are at a higher risk than other species to acquire mercury in their blood. Nest abandonment and failure to raise young are more common with higher mercury content.<ref name="JacksonEvers">{{cite journal|author1=Jackson, Alison K. |author2=Evers, David C. |author3=Etterson, Matthew A. |author4=Condon, Anne M. |author5=Folsom, Sarah B. |author6=Detweiler, Jennifer |author7=Schmerfeld, John |author8=Cristol, Daniel A. |year=2011|title=Mercury Exposure Affects the Reproductive Success of a Free-Living Terrestrial Songbird, The Carolina Wren (''Thryothorus ludovicianus'')|journal=The Auk|volume=128|issue=4|pages=759–769|doi=10.1525/auk.2011.11106|s2cid=51840097 |doi-access=free }}</ref> Exposure, and prolonged periods of cold, ice, and snow is thought to affect the wren nestling and adult populations, respectively.<ref name="Demography and Populations"/> Wrens that outlast those winters reside in sheltered areas during the season.<ref name="Bent"/>

Among the top predators of adult Carolina wrens are [[Cat predation on wildlife|domestic cats]], and snakes such as the [[timber rattlesnake]].<ref name="VJoS">{{cite journal|author1=Mitchell, Joseph C. |author2=Beck, Ruth A. |year=1992|title=Free-Ranging Domestic Cat Predation on Native Vertebrates in Rural and Native Virginia|journal=Virginia Journal of Science|volume=43|issue=1B|pages=197–208|url=http://www.vacadsci.org/vjsArchives/V43/43-1B/43-197.pdf}}</ref><ref name="GJoS">{{cite journal|author1=Parmley, Dennis |author2=Parmley, Amanda M. |year=2001 |title=Food Habits of the Canebrake Rattlesnake (''Crotalus horridus atricaudatus'') in Central Georgia |journal=Georgia Journal of Science |volume=59 |issue=4 |pages=172–80 |url=http://facstaff.gpc.edu/~jaliff/GA%20Sci%2059-4.pdf#page=16 |archive-url=https://web.archive.org/web/20131014054644/http://facstaff.gpc.edu/~jaliff/GA%20Sci%2059-4.pdf |archive-date=2013-10-14 }}</ref> [[Raccoon]]s and [[black rat snake]]s also feed on wren eggs and nestlings.<ref name="Demography and Populations"/>

==In culture== [[File:2000 SC Proof.png|thumb|right|140px|South Carolina state quarter]] In 1930, the South Carolina Federated Women's club adopted the Carolina wren as the unofficial state bird over the [[Mourning dove|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.<ref name="SouthCarolina">{{cite web|title=South Carolina State Bird – Thryrothorus ludovicianus|url=http://www.netstate.com/states/symb/birds/sc_carolina_wren.htm|publisher=NetState|access-date=31 January 2015}}</ref>

In 2000, the Carolina wren was featured on the back of the South Carolina edition of the [[50 State Quarters]].<ref name="TheUS50">{{cite web|title=The Official South Carolina State Quarter|url=http://www.theus50.com/southcarolina/quarter.php|publisher=TheUS50|access-date=31 January 2015}}</ref>

==Notes== {{Reflist|1|group=note}}

==References== {{Reflist|refs= <ref name=Brattstrom>{{cite journal|author1=Brattstrom, Bayard H. |author2=Howell, Thomas R. |year=1956|title= The Birds of the Revilla Gigedo Islands, Mexico|journal=[[Condor (journal)|Condor]]|volume=58|issue=2|pages= 107–120|doi=10.2307/1364977|url=http://sora.unm.edu/sites/default/files/journals/condor/v058n02/p0107-p0120.pdf|jstor=1364977 }}</ref>

<ref name=David>{{cite journal|author1=David, Normand |author2=Dubois, Alain |year=2011|title= The original spellings of ''Thryothorus'' Vieillot, 1816 (Vertebrata, Aves): a correction|url=http://www.mapress.com/zootaxa/2011/f/z02918p068f.pdf |journal=[[Zootaxa]]|volume= 2918|page= 68|doi=10.11646/zootaxa.2918.1.6 }}</ref>

<ref name=Mann>{{cite journal|author1=Mann, Nigel I.|author2=Barker, F. Keith|author3=Graves, Jeff A.|author4=Dingess-Mann, Kimberly A.|author5=Slater, Peter J.B.|title=Molecular data delineate four genera of "''Thryothorus''" wrens|doi=10.1016/j.ympev.2006.04.014|url=http://www.tc.umn.edu/~barke042/pdfs/Mann.et.al06.pdf|year=2006|journal=Molecular Phylogenetics and Evolution|volume=40|issue=3|pages=750–9|pmid=16750640|access-date=2007-11-22|archive-url=https://web.archive.org/web/20071202114315/http://www.tc.umn.edu/~barke042/pdfs/Mann.et.al06.pdf|archive-date=2007-12-02}}</ref>

<ref name=Martinez>{{cite journal|author1=Martínez Gómez |author2=Juan E. |author3=Barber, Bruian R. |author4=Peterson, A. Townsend |title=Phylogenetic position and generic placement of the Socorro Wren (''Thryomanes sissonii'') |doi=10.1642/0004-8038(2005)122[0050:PPAGPO]2.0.CO;2 |url=http://www.specifysoftware.org/Informatics/bios/biostownpeterson/MBP_A_2005.pdf |year=2005 |volume=122 |page=50 |journal=The Auk |archive-url=https://web.archive.org/web/20081217114932/http://www.specifysoftware.org/Informatics/bios/biostownpeterson/MBP_A_2005.pdf |archive-date=2008-12-17 |hdl=1808/16612 |s2cid=20879561 |hdl-access=free }}</ref> }}

== External links == *[https://www.mbr-pwrc.usgs.gov/id/framlst/i7180id.html Identification tips] – USGS Patuxent Bird Identification InfoCenter *[http://www.birdhouses101.com/carolina-wren.asp About] – Bird Houses 101 *{{usurped|1=[https://web.archive.org/web/20001029192001/http://www.bird-stamps.org/cspecies/13504200.htm Stamps]}} – BirdLife International * {{EBirdSpecies|carwre|Carolina Wren}} * {{VIREO|Carolina+Wren|Carolina wren}} * [https://www.floridamuseum.ufl.edu/birds/florida-bird-sounds/ Sound] – Florida Museum of Natural History

[[Category:Troglodytidae]] [[Category:Native birds of Eastern Canada]] [[Category:Native birds of the Eastern United States]] [[Category:Birds of Mexico]] [[Category:Birds of the Yucatán Peninsula]] [[Category:Birds described in 1790]] [[Category:Taxa named by John Latham (ornithologist)]] [[Category:Birds of the United States]] [[Category:Least concern biota of the United States]] [[Category: Symbols of South Carolina]]