The California thrasher (''Toxostoma redivivum'') is a large member of family Mimidae found primarily in

chaparral Chaparral ( ) is a shrubland plant community and geographical feature found primarily in the U.S. state of California, in southern Oregon, and in the northern portion of the Baja California Peninsula in Mexico. It is shaped by a Mediterranea ...

habitat in

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...

and

Baja California Baja California (; 'Lower California'), officially the Free and Sovereign State of Baja California ( es, Estado Libre y Soberano de Baja California), is a state in Mexico. It is the northernmost and westernmost of the 32 federal entities of Mex ...

. It is the only species of ''Toxostoma'' throughout most of its range.Cody, M. L. (2020). California Thrasher (''Toxostoma redivivum''), version 1.0. In Birds of the World (A. F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.calthr.01 retrieved July 27, 2021

Taxonomy and systematics

The California thrasher is closely related to the

crissal thrasher The crissal thrasher (''Toxostoma crissale'') is a large thrasher found in the Southwestern United States (western Texas, southern New Mexico, southern Arizona, southeastern California, extreme southern Nevada, and extreme southwestern Utah) to ...

(''Toxostoma crissale'') and

LeConte's thrasher LeConte's thrasher (''Toxostoma lecontei'') is a pale bird found in the southwestern United States and northwestern Mexico. It prefers to live in deserts with very little vegetation, where it blends in with the sandy soils. LeConte's thrashers ar ...

(''T. lecontei''), and the three may form a superspecies. It has two subspecies, the nominate ''T. r. redivivum'' and ''T. r. sonomae''.

Description

The California thrasher is about long and weighs up to ; it is the largest thrasher. It has a distinctive long, decurved

beak The beak, bill, or rostrum is an external anatomical structure found mostly in birds, but also in turtles, non-avian dinosaurs and a few mammals. A beak is used for eating, preening, manipulating objects, killing prey, fighting, probing for fo ...

and a long tail. It is generally deep grayish brown above with olive tones on the tail. It has a grayish buff

supercilium The supercilium is a plumage feature found on the heads of some bird species. It is a stripe which runs from the base of the bird's beak above its eye, finishing somewhere towards the rear of the bird's head.Dunn and Alderfer (2006), p. 10 Also k ...

, a dark cheek pattern and eye line, and unlike most thrashers, has dark eyes. The underparts are mostly buffy to tawny brown, with the upper breast and flanks a smoky gray. The two subspecies differ only slightly.

Distribution and habitat

The nominate subspecies of California thrasher is found from Santa Cruz and Placer counties, California, south into northwestern Baja California, Mexico. ''T. r. sonomae'' is found from

Trinity The Christian doctrine of the Trinity (, from 'threefold') is the central dogma concerning the nature of God in most Christian churches, which defines one God existing in three coequal, coeternal, consubstantial divine persons: God th ...

and adjoining counties in northern California southwards to the range of the nominate subspecies. There appears to be slight overlap allowing gene flow between them. The California thrasher is a year round resident of both slopes of the

California Coast Ranges The Coast Ranges of California span from Del Norte or Humboldt County, California, south to Santa Barbara County. The other three coastal California mountain ranges are the Transverse Ranges, Peninsular Ranges and the Klamath Mountains. ...

and the western slope of the

Sierra Nevada The Sierra Nevada () is a mountain range in the Western United States, between the Central Valley of California and the Great Basin. The vast majority of the range lies in the state of California, although the Carson Range spur lies primar ...

. It is only rarely found in the Central Valley between them. Its primary habitat is

. It also inhabits

sagebrush Sagebrush is the common name of several woody and herbaceous species of plants in the genus '' Artemisia''. The best known sagebrush is the shrub '' Artemisia tridentata''. Sagebrushes are native to the North American west. Following is an al ...

, juniper bushland, and

riparian A riparian zone or riparian area is the interface between land and a river or stream. Riparian is also the proper nomenclature for one of the terrestrial biomes of the Earth. Plant habitats and communities along the river margins and banks a ...

and oak woodlands with a dense understory. It is sometimes found in suburban parks and yards that have dense cover. In elevation it ranges generally as high as and as high as in southern California mountains.

Behavior

This species' behavior is difficult to observe because it tends to keep hidden in dense cover. In the open it runs swiftly with its tail raised.

Feeding

The California thrasher forages mostly on the ground, by digging and sweeping leaf litter and soil with its bill. It walks or hops between foraging stops. Its diet in spring is almost exclusively insects and other small invertebrates, to which it adds small soft fruits during the rest of the year. When feeding on fruits it can be in exposed situations, but is often under cover.

Breeding

The California thrasher's core breeding season spans from February into July, though it often begins in January. It often raises two broods. Both sexes build the nest, an open cup of fine twigs and roots lined with finer material such as strips of bark and dried forbs, and placed on a platform of larger twigs. The nest is usually hidden in dense shrubs, typically between above ground. The clutch size is usually three to four. Both parents incubate the eggs and brood and feed the young.

Common raven The common raven (''Corvus corax'') is a large all-black passerine bird. It is the most widely distributed of all corvids, found across the Northern Hemisphere. It is a raven known by many names at the subspecies level; there are at least ...

(''Corvus corax'') and

California scrub jay The California scrub jay (''Aphelocoma californica'') is a species of scrub jay native to western North America. It ranges from southern British Columbia throughout California and western Nevada near Reno to west of the Sierra Nevada. The Calif ...

(''Aphelocoma californica'') are common predators of eggs and nestlings.

Vocalization

The California thrasher is a "striking and exuberant songster". It mimics many of the species that share its habitat, and both sexes sing. It typically sings from elevated and exposed perches, "vigorous and 'cheerful' phrases variously repeated". It also has a wide variety of calls.

Status

The

IUCN The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...

has assessed the California thrasher as being of Least Concern. It has a very large range, and very large population that has shown only a small decrease in recent decades. Habitat fragmentation and conversion appear to be the largest threats.

References

External links

* *
California Thrasher - ''Toxostoma redivivum''
- USGS Patuxent Bird Identification InfoCenter *

- ''"Birds of San Diego coastal scrub"'' * {{Taxonbar, from=Q2225831 California thrasher California thrasher Endemic birds of Southwestern North America Native birds of the West Coast of the United States Birds of Mexico Fauna of the California chaparral and woodlands California thrasher California thrasher Least concern biota of North America