Conservation status

Most of the 60 species of wren are in no immediate danger of extinction, though with forest destruction the ranges of many have been fragmented and the total population doubtless substantially reduced. In some instances human activity has helped wren populations, notably in the case of the northern and southern house wrens, which do not occur in undisturbed thick woodland but readily take to second growth and bushland, the amount of which greatly increased as European settlement spread across the Americas. Bewick's wren expanded eastward in the nineteenth century for the same reason, but may now be retreating due to competition and egg destruction by the northern house wren.

There are several species of wren for which there is cause for concern. The unique Zapata wren of southwestern Cuba inhabits a very small area at a rather low density. Discovered in 1926, it was feared extinct in the 1970s but appears to have a current population of about 75-100 pairs. The main threats are the burning of its marshland habitat and predation by introduced mongooses. Its current status is Endangered. Nice-foro's wren (Thryothorus nicefori) was discovered in a tiny area of Colombia in 1945 and not seen again until 1989. The population is obviously quite small, and the habitat currently unprotected and at risk; Niceforo's wren was classified as critically Endangered in 2001. Apolinar's wren (Cistothorus apolinari), which is Endangered, also occurs in a very restricted range in Colombia. It has very specific habitat requirements, namely lakeside reed-beds, and much of the habitat lies in well-populated areas; several previously known areas are now lost. The two species of the genus Hylorchilus each occupy very specific and restricted habitat in southern Mexico, being tied to open forest on karst limestone outcrops. Sumichrast's wren (H. sumichrasti) has an overall range of about 2,000 sq mi (5,200 km2), but only occurs in small isolated pockets in that area; Nava's wren (H. navai) occurs in isolated pockets in an even smaller overall range. Some of the range of Nava's wren is protected, but none of that of Sumichrast's wren; they were classified in 2001 as Vulnerable and Near Threatened, respectively.

Although no full species of wren have been lost, several island races have become extinct in recent times. Thus two races of Bewick's wren, formerly found on islands off the Californias, are gone, as is the Martinique race of the southern house wren. Two other West Indian races of the same species, on

St. Lucia and Guadeloupe, are in very parlous states; and finally, an isolated race of the rock wren on San Benedicto in the Revellagigedo islands off western Mexico became extinct in a very spectacular manner in 1952, when its island home erupted catastrophically.

There are several other species or subspecies of wren found only in very small ranges: the Clarion (Troglodytes tanneri), Socorro (Thryomanes sissonii), and Cozumel wrens on the Mexican islands of the same names; the giant wren, occurring only in Chiapas state of Mexico; and the Yucatan wren (Campy-lorhynchus yucatanicus) in the Yucat√°n peninsula. Although the first two are classified as Near Threatened due to their small island range, most recent observers have found them to be fairly common. The other three species seem to be common to abundant in their limited ranges. One further South American species, the bar-winged wood wren (Henicorhina lev-coptera), has a very limited distribution in Ecuador and Peru, where it is probably protected by the remoteness of its mountain habitat.

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