Mojave River Valley Museum
Desert Wildlife -
Family: Corvidae Order: Passeriformes Class: Aves
DISTRIBUTION, ABUNDANCE, AND SEASONALITY
A common to very common, yearlong resident throughout much of the state, except
in deserts and higher elevations (Small 1994). Frequents scrub habitats, especially
with oaks; chaparral, coastal scrub, hardwood, hardwood-conifer, valley foothill riparian,
pinyon-juniper, and urban. Occurs irregularly in fall and winter in desert areas (Garrett
and Dunn 1981). Some upslope movement after breeding in foothills (McCaskie et al.
1979). The island scrub-jay (A. insularis), previously a sub-species of western scrub-jay
and resident on Santa Cruz Island (Pitelka 1951, Garrett and Dunn 1981), was
recently elevated to specific level (AOU 1995).
SPECIFIC HABITAT REQUIREMENTS
Feeding: Omnivorous; mostly eats acorns, nuts, seeds, fruits, insects, and other
invertebrates. Also eats small vertebrates, bird eggs and young. Gleans and picks
food from ground, foliage, bark and wood. Hammers nuts open. Often caches nuts
and other food in soil (Bent 1946).
Cover: Generally prefers trees and shrubs in arid woodlands and shrublands; also
frequents riparian woodlands. Common in residential areas.
Reproduction: Nest is a cup of twigs and grasses lined with rootlets and other plant
fibers; built by both sexes (Harrison 1978). Nest usually placed in dense foliage in a
tree or shrub 0.9 to 9 m (3-30 ft) high, often near water (Airola 1980).
Water: Williams and Koenig (1980) reported regular drinking visits to a spring in oak
woodland in coastal California. Drinking water probably essential.
Pattern: Prefers open woodlands and shrublands, especially with oaks.
SPECIES LIFE HISTORY
Activity Patterns: Yearlong, diurnal activity.
Seasonal Movements/Migration: Yearlong, resident in the state. May move upslope
after breeding in lower elevations of mountains. Irregularly found in desert areas and
along the Colorado River in fall and winter (Garrett and Dunn 1981). D. A. Airola
(unpublished data) suggests regular movements across the Sierra Nevada in Plumas
Home Range: Same size as territory (Airola 1980). Erickson (1937) reported
density of 1 pair per 1.6 to 4 ha (4-10 ac.).
Territory: Verbeek (1973) reported territory "about" 3 ha (7.5 ac) in coastal
California, and defended yearlong. Hardy (1961) reported a single territory/home range
of 2.1 ha (5.3 ac) in New Mexico.
Reproduction: Breeds from early March to mid-August. Monogamous; Lays 2-6
eggs, usually 2-3; clutch smaller in arid areas. Incubation 15-18 days, by female only.
Male feeds female during incubation. Altricial young tended by both parents (Harrison
1978). Young leave nest at 18-23 days (Bent 1946, Ehrlich et al. 1988).
Niche: Occasionally preyed upon by hawks, small mammals, and other corvids.
Closely associated with oaks and acorns. Steals acorn woodpecker caches.
American Ornithologists Union. 1995. Fortieth supplement to the American
Ornithologists' Union Check-list of North American Birds. Auk 112:819-830.
Airola, D. A., ed. 1980. California wildlife habitat relationships program: Northeast
Interior Zone. Vol III. Birds. U.S. Dep. Agric., For. Serv., Lassen Natl. For.,
Bent, A. C. 1946. Life histories of North American jays, crows, and titmice. U.S. Natl.
Mus. Bull. 191. 495pp.
Ehrlich, P. R., D. S. Dobkin, and D. Wheye. 1988. The birder's handbook. Simon and
Schuster, New York. 785pp.
Erickson, M. M. 1937. A jay shoot in California. Condor 39:111-115.
Garrett, K., and J. Dunn. 1981. Birds of southern California. Los Angeles Audubon
Hardy, J. W. 1961. Studies in behavior and phylogeny of certain new world jays
(Garrulinae). Univ. Kans. Sci. Bull. 42:13-149.
Harrison, C. 1978. A field guide to the nests, eggs and nestlings of north American
birds. W. Collins Sons and Co., Cleveland, OH. 416pp.
McCaskie, G., P. De Benedictis, R. Erickson, and J. Morlan. 1979. Birds of northern
California, an annotated field list. 2nd ed. Golden Gate Audubon Soc., Berkeley.
Pitelka, F. A. 1951. Speciation and ecological distribution in American jays in the
Genus Aphelocoma. Univ. Calif. Publ. Zool. 50:195-464.
Small, A. 1994. California birds: their status and distribution. Ibis Publishing Co.,
Verbeek, N. A. M. 1973. The exploitation system of the yellow-billed magpie. Univ.
Calif. Publ. Zool. 99:1-58.
Williams, P. L., and W. D. Koenig. 1980. Water dependence of birds in a temperate
oak woodland. Auk 97:339-350.
California Department of Fish and Game. California Interagency
Wildlife Task Group. 2005. California Wildlife Habitat Relationships version 8.1 personal computer program. Sacramento, California.
Western Scrub Jay
Also known as the California Jay, this species of scrub jay native to western North America, from southern Washington,
United States southeast to west Texas and south to central Mexico. The Santa Cruz or Island Scrub Jay (Aphelocoma
insularis) found only on Santa Cruz Island is a closely related species. The Western, Santa Cruz, and Florida Scrub
Jay were once considered sub-species of Scrub Jay. The Western Scrub Jay is nonmigratory.
This species is 27-31 cm (11.5 in) long including its long tail, and weighs about 80 g. Coastal Pacific birds
tend to be brighter in coloration than those of the interior, but all are patterned in blue, white, and gray.
Western Scrub Jays feed on small animals, eggs and young
of other birds, insects, and (particularly in winter) nuts and berries. True to their name, Western Scrub Jays
inhabit areas of low scrub, preferring
forests, oak woods, or sometimes
are known for hoarding and burying brightly colored objects.