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Heckle and Jeckle’s revenge
Q: Why do magpies like shiny things like jewels and
watches? (Lanney, Sandia Park, New Mexico)
European Magpie: a bird about 18 inches (45 cm) long with a tail more than
half its length. [Courtesy of Adrian Pingstone of Gloucestershire, England]
A: It’s a cool spring sunny day in Bellaterra, a small town
near Barcelona in northwest Spain. A black and white magpie strides into a
corner of a walled garden. Long black tail slightly down, black eyes
scrutinizing the ground. Past a small green bush he finds a spot that looks
familiar and pauses. Perhaps he consults his sun-related compass.
Recalling the cache record, he thinks, "I should find a nut here."
He sweeps the ground with his beak. Back and forth like a
broom. The nearby little bush bobs with the motion. Leaves and dirt fly. Aha!
Something. Yellow and round. He pecks at it — cleaning, moving it around. He
seizes the nut with the tip of his beak, hops triumphantly out, and disappears.
Why do magpies like shiny things? Because magpies are
intelligent curious beings that like to explore. Shiny things interest them as
toys, play-pretties, or something to stash away. They like to hoard.
A magpie hoards food as she finds it to stretch good times
into the future. She could risks travel perils and migrate, like swallows, to
lands with plentiful food. She could scrounge on the barest edge of survival
through the winter, like chickadees. But she doesn’t. Instead, she chooses a
frugal life style.
A
magpie, though a loud boisterous animal, takes her livelihood seriously and
hoards right after she learns to fly.
A close-up of a European magpie in Scotland that captures
the bird’s essence. [Courtesy of James Keith Lindsey, © used with permission.]
"In captive magpies, food storing begins at age of about 32
days," reports biopyschologists Bettina Pollok, Helmut Prior, and
Onur Güntürkün
in a recent study at the Ruhr-Universität at
Bochum, Germany.
The researchers found, by 42 days, a magpie retrieves food. By
55 days, she "graduates" with fully developed miserly skills about two weeks
before she leaves her parents (and their food provisions).
By then, she can put a food item into a hole, cleft, or under
a leaf with a fast fluent movement. She can hammer it into the niche with a
couple of rapid beak strokes and cover it swiftly with leaves or debris. She can
retrieve it a day or so later.
Magpies scatter their hoards, deposit a single nut in a cache,
and only store the food for a day or a few days (as opposed to jays and
nutcrackers that save for months). So, an important aspect of the job is
continuously updating their memory record of places that still have food and
those that are empty (robbed or already retrieved).
By the age of parental independence (about 70 days), the
studied magpies easily updated memory records kept on two or three hiding
places.
Not bad for a bird that doesn’t fly until age 27 days. Caching
skills, however, don’t come automatically. Young birds practice. All kinds of
non-food objects attract them — including jewels and watches. Pollok and her
team found that their magpies performed all hoarding and retrieving tasks
equally well regardless whether they used food or non-food objects. It didn’t
matter.
Further Reading:
Bettina Pollock, Helmut Prior, and Onür Güntürkün,
"Development of object permanence in food-storing magpies" Journal
Comparative Psychology. 2000 Jun;114(2):148-57.
James Keith Lindsey, A European magpie, its habitat, and food in pictures
Christopher Perrins, ed. Firefly encyclopedia of birds. Buffalo, NY:
Firefly Books (US), 2003.
Wikipedia:
Magpie
US Geological Survey:
Magpie as observed and commented on by Lewis & Clark
Magpie in
nature and myth by Peter Chou
(Answered Nov. 8, 2005)
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