Catherpes mexicanuscanyon wren

Geographic Range

The Canyon Wren is found from southern British Columbia, throughout the United States, and down into Mexico.

Habitat

The Canyon Wren usually makes its home in arid regions that contain cliffs, steep-sided canyons, rocky outcrops, and boulder piles. Rock crevices and spaces furnish shade, nest sites, and foraging sites. Stream-carrying canyons that provide shelter from the heat and sun with shade are preferred.

Physical Description

The upper parts of the Canyon Wren are rusty brown with a grey head and back. The amount of white spotting on the dorsals varies. The lower face, throat, and and upper breast are white. The underparts of the bird are chestnut and are speckled with black and white. The tail is a brownish color with black barring. The head has a flattened appearance and the bill is long and slender.

Reproduction

Canyon Wrens are monogamous and pairs remain together throughout the year. A pair bond may last for more than one breeding season. There is, however, little information on pair formation. The bird nests in rock caverns, crevices, cliffs, or banks. Nests are often protected by a protruding ledge or shelf covering. The cup-shaped nest is built by both the male and the female. The base is made of coarse material like twigs and grasses and is then lined with lichens, plant down, wool, cobwebs, or feathers. Average clutch size is five elliptical white eggs marked with specks of reddish brown that may not be noticeable. Incubation is performed by the female and begins when the last egg is laid. It lasts from 12-18 days, and the male regularly feeds the female during this period. When the eggs are hatched, both parents care for their young. After ten days the chicks are able to forage with their parents and feed themselves.

Behavior

The Canyon Wren is a sedentary species, although it may make short altitudinal movements. In the winter, some birds withdraw from high elevations and from the eastern and northern portions of their range. These birds may wander in the winter. Mating pairs are often seen foraging together and may sing spontaneously during the winter months.

Communication and Perception

Food Habits

The species' basic diet consists of spiders and insects that are gleaned from rocky surfaces. Ocassionally, the Canyon Wren attempts flycatching. It is well adapted to foraging in rock crevices with its long slender bill and flattened cranium. These features enable it to probe deeply into small crevices.

Conservation Status

The Canyon Wren population is under no current threat. Their secluded habitat protects them from most human activities. The only human threat that has been observed is recreational rock climbing. Climbers may disturb nesting grounds.

Other Comments

The Canyon Wren may have an inconspicuous appearance, but its loud melodious song is often heard echoing throughout the canyons. The male sings daily throughout he breeding season. Female song is rare and is usually in response to males. Due to its inaccessible habitat, the Canyon Wren is one of North America's least studied birds.

Contributors

Marie S. Harris (author), University of Michigan-Ann Arbor.

Glossary

Nearctic

living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

acoustic

uses sound to communicate

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chaparral

Found in coastal areas between 30 and 40 degrees latitude, in areas with a Mediterranean climate. Vegetation is dominated by stands of dense, spiny shrubs with tough (hard or waxy) evergreen leaves. May be maintained by periodic fire. In South America it includes the scrub ecotone between forest and paramo.

chemical

uses smells or other chemicals to communicate

desert or dunes

in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

tactile

uses touch to communicate

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

visual

uses sight to communicate

References

Jones, Stephanie, L.

Dieni, Joseph, Scott. 1995. The Birds of North America. No197.