Campylorhynchus brunneicapillus
The Cactus Wren is a resident of the brush lands of southwestern Texas. It is usually seen singly or in pairs, but near the end of the breeding season occurs in small family groups (Oberholser 1974). Those birds that forage and nest around human habitations become accustomed to people and show little fear in their presence. Cactus Wrens are extremely curious and closely inspect everything within their domain, often entering sheds and parked cars when the doors or windows are left open. They often sing from an exposed perch and on the ground they may run swiftly but usually fly if going any distance. Flights are usually short, direct, and close to the ground.
Cactus Wrens forage in shrubs and trees for insects or on the ground where they diligently search for food. Small debris is often lifted with the bill while the wren peers beneath for hidden prey. Food items include beetles, ants,
wasps, weevils, grasshoppers, bugs and spiders, as well as the fruits of various cacti, elderberry, hackberry and cascara buckthorn. In southern Texas the facial feathers of those wrens eating the tunas of prickly pear are often stained reddish by the juice. Cactus Wrens are also fond of sweet corn and will even eat dry cornmeal from a gravity feeder (Bent 1948, Casto 1973). Most of their water requirement is apparently derived from the insects and cactus fruits that are eaten (Bent 1948, Anderson and Anderson 1973). Dust bathing is performed each evening before going to roost but water bathing is seldom observed (Anderson and Anderson 1973).
DISTRIBUTION: The Cactus Wren is a permanent resident in southwestern Texas but is notably absent as a breeding species in most of the Panhandle, eastern Texas, and the middle and upper Texas coast. Cactus wrens occur from near sea level to altitudes of 1829 meters (6000 feet).
SEASONAL OCCURRENCE: Cactus Wrens are permanent residents throughout their range in Texas. Nest building normally begins in early February. Although 3-7 eggs may be laid with 4-5 being cited as the usual number (Harrison 1978, Oberholser 1974), studies in Arizona and New Mexico have shown the usual number to be 3 or 4 (Anderson and Anderson 1973, Marr and Raitt 1983).
The TBBA data document a nest with eggs as early as 21 March in Latilong 26098, Quad Cl and a nest with young as late as 21 June in Latilong 28099 Quad Bl.. Oberholser (1974) gives a range of egg dates from 12 March to 6 August with recently fledged young being seen as late as 11 September. An early egg date of 2 January has been recorded in Arizona (Anderson and Anderson 1973).
Wrens in New Mexico initiate egg-laying when high temperatures predict favorable conditions for the emergence of band-winged grasshoppers during the time they will be feeding their nestlings (Marr and Raitt 1983)
BREEDING HABITAT: Cactus Wrens build roosting, breeding, and secondary nests. The roosting nest is built at the end of the breeding season and is used during the winter.
If it is still intact in the spring the roosting nest may be reworked and used for breeding, or a completely new nest may be built. Secondary nests are built by the male in the vicinity of the breeding nest and are used for roosting by the male, recently fledged birds, or as breeding nests for subsequent broods (Anderson and Anderson 1973).
The exterior of the breeding nest is pouch-shaped with an opening at one end. The nest is about 30.5 cm (12 inches) long. The entrance is about 3.8 cm (1.5 inches) in diameter and opens into a passageway leading to a cavity about 7.5 cm (3 inches) in diameter. A twig or branch growing below or at the side of the entrance serves as a “doorstep” The first breeding nest of the season is constructed by both sexes. The materials used are mainly grasses and the small, flexible stems of annuals. The nest chamber is lined with feathers. Around human habitations nests often include bits of paper, string, cloth and other materials (Bent 1948, Anderson and Anderson 1973)
Nests are usually placed at heights of 0.6 to 2.7 meters (2-9 feet) in plants such as prickly pear, cholla, mesquite, granjeno, yucca, sumac, catclaw and red-flowered mistletoe. Nests are occasionally placed on structures of human construction and Cactus Wrens have even been induced to use nest boxes.
Curve-billed Thrashers often destroy the roosting nests but apparently do not attack breeding nests that are in use (Bent 1948, Anderson and Anderson 1973).
Eggs are incubated by the female for about 16 (range 15-8) days. Both parents feed the young who leave the nest at about 21 (range 19-23) days of age. As many as six broods may be produced and the young of earlier broods sometimes help tend the young of later broods (Anderson and Anderson 1973, Harrison 1978).
STATUS: With the exception of possible or probable breeding in north-central Texas, there has been no major change in the breeding distribution of the Cactus Wren since the publication of Oberholser’s account in 1974. Lockwood and Freeman (2000) consider Cactus Wren to be an uncommon to locally common resident from the Lower Rio Grande Valley, north through the Edwards Plateau to the southeastern Panhandle, and throughout the Trans-Pecos.
Text by Stan D. Casto (Posted with updates 2006)
Literature cited.
Anderson, A. H. and Anderson, A. 1973. The Cactus Wren. University of Arizona Press, Tucson
Bent, A. C. 1948. Life histories of North American nuthatches, wrens, thrashers, and their allies. U. S. Nat. Nus. Bull. 195 (1964 Dover Reprint).
Casto, S. D. 1973. Cornmeal as food of the Cactus Wren and Golden-fronted Woodpecker. Bull. Tex. Ornithol. Soc. 6:7.
Harrison, C. 1978. A field guide to the nests, eggs and nestlings of North American birds. Wm. Collins Sons & Co., Glasgow.
Lockwood, M. W. and B. Freeman. 2004. The TOS handbook of Texas birds. Texas A&M University Press, College Station.
Marr, T. B. and R. J. Raitt. 1983. Annual variations in patterns of reproduction of the Cactus Wren (Campylorhynchus brunneicapillus). Southwest. Nat. 28: 149-156.
Oberholser, H. C. 1974. The bird life of Texas. University of Texas Press, Austin.