These birds are physically ready to mate after about a year, however, until males are able to defend a territory, females will not mate with them, these males are considered 'floaters'.
They can stay in their 'floating' stage for up to 7 years. Carmen, ; Curry, After a male finds a mate, he builds a nest before mating. Nests are made from plant material and twigs, as well as horse and cow hair. Females cover their chicks after they hatch. Nestlings usually eat moth or butterfly larvae and acorns. Males keep their nest clean by removing waste while the nestlings develop. Curry, In the wild, the longest lifespan for this species is 15 years and 9 months, while in captivity, this species has survived up to 19 years and 8 months.
Clapp, et al. Western scrub-jays use a gliding flight, but move their wings more when they spot a prey item, or when they are trying to avoid a predator. When they are on the ground, western scrub-jays travel by hopping. Like other jays, these birds are diurnal, social, and rather vocal. Males defend territories during the breeding season and form social hierarchies based on the quality of their territory. When western scrub-jays find a dead member of their species, they call other jays to the spot by making loud calls.
Carmen, ; Curry, ; Iglesias, et al. Western scrub-jays keep an average territory size of Curry, ; Sibley, Western scrub-jays communicate in several ways. If they see a dead western scrub-jay on the ground, they react by flying from tree to tree and making loud screams, when they do this, other nearby western scrub-jays also begin vocalizing. They also have a specific vocalization for finding a mate. Western scrub-jays sing to possible mates in a sequence of tones with a soft pitch.
Likewise, western scrub-jays use a specific call to defend their territory from an outsider. While resting on a branch, they make loud, repetitive screams from low to high pitch while raising their bill in the air. By using their sense of sight and smell, they are able to determine the food quality of the seeds they find.
Curry, ; Iglesias, et al. Western scrub-jays are omnivorous. Depending on the time of year, these birds eat plant or animal material. From October to February, they mostly eat acorns and from May to June they mostly eat fruit.
They are most likely to eat animal matter during the month of April. Western scrub-jays eat fruits, mainly cherries and prunes, as well as other grains and vegetables such as oats and corn. These birds also eat insects including beetles , bees , moths , grasshoppers , and planthoppers. Western scrub-jays may prey on animals including small birds and their eggs, amphibians such as California slender salamanders , and reptiles such as western fence lizards.
Depending on where they live, their bills have different shapes to help feeding. Jays found in areas with dense oak trees have deep, hooked bills, which helps them eat nuts. Jays found in areas with dense pinon pines have a more pointed bill, which helps them open pinon cones.
They usually hide seeds in the ground, but they may also hide them under rocks or on top of telephone poles and cover them with leaves. Clayton, ; Curry, ; Dunn and Tessaglia-Hymes, Western scrub-jays use high-pitched vocalizations when they feel threatened by predators such as raccoons , long-tailed weasels , western spotted skunks , striped skunks , western gray squirrels , fox squirrels and a host of snake and bird species.
Common avian predators include American crows , Cooper's hawks , sharp-shinned hawks , golden eagles , red-tailed hawks , and prairie falcons. Clayton, ; Curry, Western scrub-jays help disperse seeds throughout their habitats. They disperse seeds from a variety of oak, pine, and juniper species, specifically Colorado pinon pines , and bury them to eat them later.
If, however, they do not return, the seeds have a chance to germinate. These jays also host lice species including Philopteras cassipes , Brueelia deficiens and Myrsidea species. Western scrub-jays form mutualistic relationships with Columbian black-tailed deer by eating ticks, hippoboscid flies keds or louse flies , and deer flies from the deer's skin. Bush, et al. Western scrub-jays can cause crop damage in fruit and pistachio orchards.
They can also help spread West Nile virus. Curry, ; Ladeau, et al. Humans often provide food for western scrub-jays, especially during winter months when less food is available. Choose a temperature scenario below to see which threats will affect this species as warming increases. The same climate change-driven threats that put birds at risk will affect other wildlife and people, too.
Latin: Cyanocitta cristata. Latin: Perisoreus canadensis. Latin: Nucifraga columbiana. Latin: Aphelocoma coerulescens. Latin: Cyanocorax yncas. Latin: Aphelocoma insularis. Latin: Aphelocoma wollweberi. Latin: Gymnorhinus cyanocephalus. Latin: Cyanocitta stelleri.
Latin: Aphelocoma woodhouseii. Membership benefits include one year of Audubon magazine and the latest on birds and their habitats. Your support helps secure a future for birds at risk. Our email newsletter shares the latest programs and initiatives. This is the "blue jay" of parks, neighborhoods, and riverside woods near the Pacific Coast. Pairs of California Scrub-Jays are often seen swooping across clearings, giving harsh calls, with their long tails flopping in flight.
They readily come to backyard bird feeders. Until recently, this jay was considered part of the same species as the Woodhouse's Scrub-Jay; the two were officially "split" in July Photo gallery. Feeding Behavior Forages on the ground and in trees, singly or in family units during breeding season, sometimes in flocks at other seasons. Eggs , sometimes They move thousands of acorns each fall, often depositing them in damp soil.
Western scrub-jays have been shown to have an ability to plan ahead in choosing food storage sites, remembering the locations of their caches and storing enough food to plan for the future. Jays can also be quite sneaky when it comes to acquiring and storing food. They steal acorns from acorn woodpecker caches and from stores hidden by other jays, and then look around to make sure no one is watching before they hide their prize again.
They have also been observed picking parasites such as ticks from the backs of mule deer. Western scrub-jay pairs make basket-shaped nests of twigs lined with fibers and hair. Nests are built low and concealed behind foliage, generally in an oak or pinyon pine. They have one brood of one to five eggs. The young remain with the parents for about five months. Pairs stay together through the year. They are very territorial during the breeding season. Jays are relatively long-lived birds and can reach over 15 years of age in the wild.
Western scrub-jays are common, and some populations may be increasing. However, one subspecies in southeastern California may be vulnerable to disturbance and is listed as a species of concern in the state. Some populations are being affected by West Nile virus. They will screech over the body, attracting other jays, for as long as 30 minutes and stay near the body for a day or two.
Baughman, M. National Geographic reference atlas to the birds of North America. Washington, D. Western scrub-jay funerals: cacophonous aggregations in response to dead conspecifics, Animal Behaviour. Vol 84 5 , November
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