a very interesting bird
as it name would say it prefers scrub forests and forests. it is found from california to the pacific northewest. it eats acorns,bugs,carrion.it often fights for food with the crows and ravens.this species is very clever..
Regularity: Regularly occurring
Type of Residency: Year-round
Global Range: RESIDENT: southwestern Washington to southwestern Wyoming, Colorado, and central Texas south through the southwestern U.S. to southern Baja California and Oaxaca, Puebla, and west-central Veracruz, Mexico.
Length: 29 cm
Weight: 91 grams
Gray-breasted (Mexican) jay is grayer, lacks strong contrast between throat and breast, lacks white eyebrow. Pinyon jay is more uniformly blue and has a blue throat with white streaks; scrub-jay's tail is much longer than that of the pinyon jay.
Habitat and Ecology
Comments: Scrub (especially oak, pinyon and juniper), brush, chaparral and pine-oak associations; also riparian woodland, gardens, orchards, mangroves (southern Baja California), and tropical deciduous forest (southern Mexico) (Subtropical and Temperate zones, upper Tropical Zone in southern Mexico) (AOU 1983, 1995). Nests usually in low trees or shrubs, 0.5-3.5 m above ground (Terres 1980).
Non-Migrant: Yes. At least some populations of this species do not make significant seasonal migrations. Juvenile dispersal is not considered a migration.
Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).
Locally Migrant: No. No populations of this species make annual migrations of over 200 km.
Comments: Feeds on nuts (acorns, pinyon nuts), grains (corn, oats), fruit, insects (wasps, bees, caterpillars cutworms, grasshoppers, etc.), mollusks, eggs and young of small birds, mice, shrews, frogs, lizards, etc. (Bent 1946).
Known prey organisms
This list may not be complete but is based on published studies.
Travels alone or in small family groups. In Oaxaca, Mexico, occurred in temporally stable groups of 2-6 adults; territories averaged 1.5 ha (Burt and Peterson 1993). In coastal California, territories averaged "about 3 ha" (Verbeek 1973), and in New Mexico, a single territory measured 2.1 ha (Hardy 1961).
Predation impacted by noise
Francis et al. (2009) studied bird communities in woodlands near gas wells in New Mexica, USA. Though noise decreases nesting success and species richness in general, there was an indirect benefit. Where noise was high, western scrub jays were less able to prey on nests of other birds. This is likely because vocalizations of the prey species were less noticeable over the noise of compressors. The effect was particularly beneficial to species such as house finches (Carpodacus mexicanus) and black-chinned hummingbirds (Archilochus alexandri)
- Clinton D. Francis, Catherine P. Ortega, Alexander Cruz, Noise Pollution Changes Avian Communities and Species Interactions, Current Biology, Volume 19, Issue 16, 25 August 2009, Pages 1415-1419, ISSN 0960-9822, DOI: 10.1016/j.cub.2009.06.052.
Life History and Behavior
Lifespan, longevity, and ageing
In Oaxaca, Mexico, nested at least from early April to late July (Burt and Peterson 1993). Clutch size is 2-7 (usually 4-6; 3 in Oaxaca, with reduction to 2 fledglings typical). Incubation lasts about 16 days, by female. Young are tended by parents and (in Oaxaca) young of previous brood. Young leave nest at about 18 days. First breeds as early as 1 year in some areas. Long-term pair bond. High adult survivorship. Breeds only in pairs in most of range (except southern end of range in Mexico). In Oaxaca, helpers aided in predator defense, territorial defense, and feeding fledglings; singular breeding was the norm (Burt and Peterson 1993).
Molecular Biology and Genetics
Barcode data: Aphelocoma californica
Below is a sequence of the barcode region Cytochrome oxidase subunit 1 (COI or COX1) from a member of the species.
See the BOLD taxonomy browser for more complete information about this specimen and other sequences.
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Download FASTA File
Statistics of barcoding coverage: Aphelocoma californica
Public Records: 18
Specimens with Barcodes: 23
Species With Barcodes: 1
IUCN Red List Assessment
Red List Category
Red List Criteria
National NatureServe Conservation Status
Rounded National Status Rank: N5 - Secure
NatureServe Conservation Status
Rounded Global Status Rank: G5 - Secure
Names and Taxonomy
Comments: Formerly considered conspecific with A. COERULESCENS and A. INSULARIS (see AOU 1995). The three groups of this species may represent distinct species: A. CALIFORNICA (California Scrub-Jay), A. WOODHOUSEI (Woodhouse's Scrub-Jay), and A. SUMICHRASTI (Sumichrast's Scrub-Jay) (AOU 1998).