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The Bewick's wren (''Thryomanes bewickii'') is a wren native to North America. At about long, it is grey-brown above, white below, with a long white eyebrow. While similar in appearance to the Carolina wren, it has a long tail that is tipped in white. The song is loud and melodious, much like the song of other wrens. The song is broken into two or three individual parts; one individual male may exhibit up to twenty-two different variations on the song pattern, and may even throw in a little ventriloquism to vary it even further.〔https://books.google.com/books?id=oBYzqOAZHpcC&pg=PA260&lpg=PA260&dq=%22bewick%27s+wren%22+song+variations&source=bl&ots=hL0FAOuSvm&sig=oiEh-gMIwUWOfAhQqcQ02Pi6C0Q&hl=en&sa=X&ei=qXjvVLicJcPZoASik4KADg&ved=0CH8Q6AEwEA#v=snippet&q=two%20dozen&f=false〕 It lives in thickets, brush piles and hedgerows, open woodlands and scrubby areas, often near streams. It eats insects and spiders, which it gleans from vegetation or finds on the ground. Wrens are sometimes observed foraging with chickadees and other birds. Its range is from southern British Columbia, Nebraska, southern Ontario, and southwestern Pennsylvania, Maryland, south to Mexico, Arkansas and the northern Gulf States. The Bewick's wren does not migrate. The nest is cup-shaped and located in a nook or cavity of some kind. It lays 5–7 eggs that are white with brown spots. The Bewick's wren produces two broods in a season. Pairs are more or less monogamous when it comes to breeding, but go solitary throughout the winter.〔 This is currently the only species of its genus, ''Thryomanes''. The Socorro wren, formerly placed here too, is actually a close relative of the house wren complex, as indicated by biogeography and mtDNA NADH dehydrogenase subunit 2 sequence analysis, whereas ''Thryomanes'' seems not too distant from the Carolina wren.〔 ==Subspecies== A list of commonly recognized subspecies follows. Two have gone extinct during the 20th century, mainly due to habitat destruction and cat predation.〔 * ''T. b. bewickii'' – (Audubon, 1827): nominate, Midwestern USA from NE Kansas to Missouri and E Texas. Includes ''T. b. pulichi'' as a junior synonym. * ''T. b. altus'' – Aldrich, 1944: Formerly in Appalachian region; S Ontario to South Carolina, now quite rare. Possibly an endangered subspecies, but possibly not distinct from ''bewickii''. * ''T. b. cryptus'' – Oberholser, 1898: Central Kansas to N Tamaulipas in Mexico. Includes ''T. b. niceae''. Southeastern birds are sometimes separated as ''T. b. sadai''. * ''T. b. eremophilus'' – Oberholser, 1898: E California inland, south to Zacatecas in Mexico. * ''T. b. calophonus'' – Oberholser, 1898: SW British Columbia, Canada, to W Oregon. Includes ''T. b. ariborius'' and ''T. b. hurleyi''. The former name refers to the population found in the area of Seattle and Vancouver; these birds are sometimes called Seattle wren. * ''T. b. marinensis'' – Grinnell, 1910: Coastal NW California to Marin County. * ''T. b. spilurus'' – (Vigors, 1839): Coastal California from San Francisco Bay to Santa Cruz County. * ''T. b. drymoecus'' – Oberholser, 1898: SW Oregon to California Central Valley. * ''T. b. atrestus'' – Oberholser, 1932: S Oregon to W Nevada. Probably not valid. * ''T. b. correctus'' Grinnell. SW coastal California to Mexican border; possibly synonym of ''charienturus''. * ''T. b. charienturus'' – Oberholser, 1898: N Baja California Peninsula to about 30°N. * ''T. b. magdalenensis'' – Huey, 1942: SW Baja California Peninsula from 26 to 24°N. * ''T. b. nesophilus'' Oberholser. Santa Rosa, Santa Cruz, and Anacapa Islands, California; probably also Santa Barbara and San Nicolas; found on the mainland in winter. Possibly synonym of ''charienturus''. * ''T. b. catalinae'' – Grinnell: Santa Catalina Island, California; found on the mainland in winter. Possibly synonym of ''charienturus''. * ''T. b. cerroensis'' – (Anthony, 1897): Cedros Island (Mexico) and W central Baja California. Includes ''T. b. atricauda''. * ''T. b. leucophrys'' † – (Anthony, 1895): San Clemente Bewick's wren. Formerly San Clemente Island, California. ::Extinct since the 1940s due to habitat destruction by feral goats and sheep. Also called ''T. b. anthonyi''. Observations of ''leucophrys'' in 1897〔 refer to ''cerroensis''; at that time, the San Clemente wren was considered a good species which included the Cedros population. * ''T. b. brevicauda'' † – Ridgway, 1876: Guadalupe Bewick's wren. Formerly Guadalupe Island, Mexico. ::This subspecies is extinct since (probably) the late 1890s due to habitat destruction by feral goats and predation by feral cats. Overcollecting by scientists might have hastened its demise.〔 It was last collected (3 specimens) by Anthony and Streator in May 1892〔 and seen but found to be "nearly extinct" on March 22, 1897.〔 It was not found by Anthony in several searches between 1892 and 1901 and considered certainly extinct by 1901;〔 a thorough search in 1906 confirmed the subspecies' extinction.〔〔The often-reported extinction date of 1903 seems to be the first record of its absence rather than the last record of its presence. Actually, there appears to be no post-1897 record. The schedule of Anthony's visits after 1892 is not known; if he visited the island before 1897 he must have overlooked the last remnant of the population and thus his extinction date of 1901 may be called into question. By the balance of evidence, it is likely however that the subspecies became extinct between 1897 and 1901.〕 * ''T. b. murinus'' – (Hartlaub, 1852): Eastern and central Mexico. * ''T. b. bairdi'' – (Salvin and Goodman): SE Mexico to S Puebla. * ''T. b. percnus'' – (Oberholser): Jalisco to Guerrero, Mexico. The last three are sometimes united as ''T. b. mexicanus''. The validity of subspecies needs to be verified using freshly caught birds and/or molecular data, as specimens are prone to foxing quickly.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Bewick's wren」の詳細全文を読む スポンサード リンク
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