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Listen
for the pinyon jay's call which has been described as a rhythmic
krawk-kraw-krawk repeated two or three times.
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Our local pinyon forests are ravaged by drought
and an explosion of ips beetles. The beetles have weakened the trees by
feeding on the living tissue beneath the bark. Desiccated by drought, the
trees are unable to produce enough sap to fill the beetles’ tunnels
and therefore "pitch them out." The end result of this dual threat
is miles of forest filled with dead and dying pinyon trees, facing further
challenge by impending wildfire.
Many of us have gained a newfound appreciation for healthy
pinyon pines, and are left wondering how our desert woodlands will ever
regenerate following this harsh turn of events. Enter our feathered friend
the pinyon jay. This distinctive blue bird is dependent upon the pinyon
pine for its survival, with 90% of its winter diet consisting of pinyon
pine seeds. The pine in turn, is equally dependent upon the bird, who inadvertently
plants pinyon seeds while storing winter food.
The pinyon jay is a completely blue, robin-sized bird whose
Latin name, Gymnorhinus cyanocephalus, aptly translates as "Naked-nose
blue-head." (See its photo at www.nhptv.org/natureworks/pinyonjay.htm
.) Most other jay species have bristled feathers surrounding their nostrils.
The pinyon jay’s “nose” is naked because it lacks these
feathers- a critical adaptation for a bird that uses its beak to extract
seeds from cones full of pine sap. Another pinyon jay adaptation is its
expandable esophagus, which holds 50 pinyon seeds.
With its throat filled with seeds, the jay will fly up
to seven miles, cough up the seeds, and bury (or cache, pronounced “cash”)
them beneath soil and forest litter. Seeds are intentionally buried in sunny
areas where the snow melts off during warmer winter periods, making them
easier to dig up during winter’s famine. A pinyon jay can cache as
many as 20,000 seeds in one season! This winter food supply allows the jay
to remain in its territory year round, rather than migrating to find food.
Yet stored food is only half the battle. In winter, the jay must relocate
its cached supplies. It is remarkably adept at remembering seed locations,
recovering about 75% of the cached seeds, thanks to the use of landmarks
and visual cues.
What happens to the seeds that are left behind? They have
a high probability of germinating, thanks to the soil depth and sunny location
in which the jays cache them. And so the pinyon pine benefits from its symbiotic
relationship with the jay. Pinyon jays plant pinyon trees.
Keep close watch over the healthy pinyon pines that remain.
Should they produce a good cone crop this autumn, expect to see flocks of
noisy pinyon jays harvesting the seeds, and ensuring the slow but steady
return of our pinyon forests.
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