Magpies

Identification
Magpies
have lived in close association with humans for centuries. They are
found throughout the Northern Hemi-sphere and are a common bird of
tales and superstitions. Magpies and their many brash behaviors are
the basis for the cartoon characters Heckyl and Jeckyl.
Magpies
are members of the corvid family, which also includes ravens, crows,
and jays. They are easily distinguished from other birds by their
size and striking black and white color pattern. They have unusually
long tails (at least half of their body length) and short, rounded
wings. The feathers of the tail and wings are iridescent, reflecting
a bronzy-green to purple. They have white bellies and shoulder
patches and their wings flash white in flight. Like other corvids,
they are very vocal, even boisterous. Typical calls include a
whining “maag” and a series of loud, harsh “chuck” notes. Where
magpies are not harassed, they can be extremely bold. If hunted or
harassed, though, they become elusive and secretive.
Two
distinct species are found in North America, the black-billed and
yellow-billed magpies (Fig. 1). They are easily separated by bill
color, as their names imply, and by geographic location.
Black-billed magpies average 19 inches (47 cm) in length and 1/2
pound (225 g) in weight. They have black beaks and no eye patches.
Yel-low-billed magpies are somewhat smaller (17 inches [42 cm]) and
weigh slightly less than 1/2 pound (225 g). Their bills and bare
skin patches behind their eyes are bright yellow. Their range
coincides with a few species of mistle-toe that are often used in
building their nests.
Food Habits
Magpies
are omnivorous and very opportunistic, a characteristic typical of
other corvids. They have a preference for animal matter, primarily
insects, but readily take anything that is available. Congregations
of magpies can commonly be seen along roadsides feeding on animals
killed by cars or in ripening fruit and nut orchards. They also pick
insects from the backs of large animals and were historically
associated with large herds of bison. Their diet changes during the
year, reflecting the availability of foods during the different
seasons. The black-billed magpie’s diet typically consists of over
80% animal matter: insects, carrion, small mammals, small wild
birds, hatchlings, and eggs. The remainder of its diet consists of
fruits and grains. The yellow-billed magpie’s diet is about 70%
animal matter and 30% fruits, nuts, and grains. Nestling magpies are
fed a diet of mostly animal matter, primarily insects. Magpies often
store or cache food items in shallow pits that they dig in the
ground. This behavior is commonly observed in winter, but can be
seen throughout the year.
General Biology, Reproduction, and Behavior
Magpies,
like other corvids, are intelligent birds. They learn quickly and
seem to sense danger. They are boisterous and curious, but shy and
secretive in the presence of danger. They mimic calls of other birds
and can learn to imitate some human words. They have readily adapted
to the presence of humans and have taken advantage of new food
sources provided. Magpies are gregarious and form loose flocks
throughout the year. Pairs stay together yearlong, but mates are
replaced rapidly if one is lost. Nest building typically begins in
early March for black-billed magpies and earlier for yellow-billed
magpies. Black-billed magpies build large nests, sometimes 48 inches
(125 cm) high by 40 inches (100 cm) wide, made of sticks in low
bushes or in trees usually within 25 feet (7.5 m) from the ground.
The nest chamber is a cup lined with grass and mud, and normally
enclosed by a canopy of sticks. Two entrances are common.
Yellow-billed magpies build similar nests, but theirs often resemble
mistletoe clumps, which are common in trees where they nest.
Magpie
nests are usually found in small colonies. Magpies nest once a year,
but will re-nest if their first at-tempt fails. Other species of
birds and mammals often use magpie nests after they have been
abandoned. Black-billed magpies lay 6 to 9 eggs, whereas
yellow-billed magpies lay 5 to 8. Incubation normally starts in
April, except further north where it may be-gin as late as mid-June.
The incubation period is 16 to 18 days and young are populations
were greatly suppressed.
Legal Status
Magpies
are protected as migratory Non-game birds under the Federal
Migratory Bird Treaty Act. Under the Federal Codes of Regulation (CFR
50, 21.43) it is stated, however, that “a Federal permit shall not
be required to control . . . magpies, when found committing or about
to commit depredations upon ornamental or shade trees, agricultural
crops, livestock, or wildlife, or when concentrated in such numbers
as to constitute a health hazard or other nuisance. . . .” Most
state or local regulations are similar, but consult authorities
before taking any magpies.