Pinyon Jay

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Image:PinyonJay.JPG

Common Name: Pinyon Jay
Scientific Name: Gymnorhinus cyanocephalus

Size: 10.2-11.4 inches (26-29 cm); Wingspan: 18.1 inches (46 cm)

Habitat: North America; residents from central Oregon to western South Dakota, south to northern Baja California, northwestern and east-central Arizona, central New Mexico, and western Oklahoma. They winter throughout their breeding range and irregularly from southern Washington to northwestern Montana, and south to Mexico and central Texas. When pinyon seed crops are poor, pinyon jays may wander to central Washington, northwestern Oregon, northern Idaho, northwestern Montana, throughout the Great Basin, Nebraska, Kansas, central-western and southwestern California, southeastern Arizona, central Texas, and northern Chihuahua.

It lives in foothills where pinyon-juniper woodland, sagebrush, scrub oak, and chaparral communities occur.

Status: Vulnerable. Global population: Unknown population. This species has undergone a large and statistically significant decrease over the last 40 years in North America (-74.8% decline over 40 years, equating to a -29.1% decline per decade). The major threat to this species is the destruction of its major habitat type, pinyon-juniper woodland. Land managers have followed a policy to eradicate this woodland, with the U.S. Forest Service classifying it as "non-commercial" and placing it in a "no-value" category. During the 1940s-1960s, major programs to eradicate the entire habitat were carried out, during which possibly millions of G. cyanocephalus died owing to habitat destruction. Currently herbicides, mechanical ploughing and fire are used to turn pinyon-juniper woodland into pasture land for cattle. Fire-suppression policies in south-west U.S.A. have led to huge, uncontrolled wildfires that consumed large areas of suitable habitat in the late 1990s. A "catastrophic" drought in the early 2000s also caused considerable mortality. The decline of pinyon pine and associated encroachment of juniper associated with global warming are primary factors restricting habitat and limiting reproductive success.

Diet: Seed, fruit, berries and insects. The seed of the Pinyon pine is the staple food but they supplement their diet with fruits and berries. Insects of many types are also eaten and sometimes caught with its feet.

Nesting: Sexes are alike. Adults are a bluish-grey color with deeper head coloring and whitish throat with black bill, legs and feet. Juvenile are uniformly dull gray in color with lighter beaks.

Pinyon jays appear to form perennial, monogamous pair bonds that last an average of 2.5 years. The nest is always part of a colony but there is never more than one nest in a tree. Sometimes the colony can cover quite extensive areas with a single nest in each tree (usually juniper, live oak or pine).

There are usually 3–4 eggs laid, quite early in the season. Incubation is usually 16 days. The male bird normally brings food near to the nest, and the female flies to him to receive it and take back to the nest to feed the chicks that fledge around 3 weeks later. Young are normally fed only by their parents, but once they reach near-fledging size they can sometimes receive a meal from any passing member of the colony, which can continue for some time after leaving the nest.

Cool Facts: Pinyon Jay social organization is complex, with permanent flocks that may include more than 500 individuals. Many birds spend their entire lives in their natal flocks. Individuals that do disperse, usually females before they are one year of age, generally travel only short distances. Several birds always seem to act as sentries for the flock, watching out for predators while their companions are feeding.

Pinyon jays have a symbiotic relationship with the pinyon. Pinyon trees provide pinyon jays with food, nesting and roosting sites, and breeding stimuli. Pinyon jays influence seed dispersal, establishment, and genetic structure of pinyon populations.

Although omnivorous, the Pinyon Jay is committed to the harvest, transport, caching, and later retrieval of pine seeds. It is aided by a relatively long, strong bill; an expandable esophagus; and long, strong wings. Individuals have excellent spatial memories that allow them to find most of their hidden seeds months after caching, even through snow. Mated pairs of Pinyon Jays appear to coordinate their caching so that their cache locations are known to each other, especially the male. Although this behavior is difficult to observe in the wild, data from aviary observations and experiments confirm this arrangement.

The Pinyon Jay's bill is featherless at its base (hence the name Gymnorhinus = bare nostrils). Nearly all other members of the family Corvidae have feathers covering their nostrils. The Pinyon Jay can probe deep into pitch-laden cones without fouling the feathers that would cover the nostrils of other jays.


Found in Songbird Remix Woodland Jewels

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