Magpies
General Magpie Facts
Identification
Magpies have lived in close association
with humans for centuries. They are
found throughout the Northern Hemisphere
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. Yellow-
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.
Range
Magpies are found in western North
America. Ranges of the two species do
not overlap. Black-billed magpies are
found from coastal and central Alaska
to Saskatchewan, south to Texas, and
west to central California, east of the
Sierra-Cascade range. They migrate in
winter to lower elevations, and in
northern parts of their range, south to
areas within their breeding range.
Occasionally they wander to areas further
east and south of their normal
range.
Yellow-billed magpies are residents of
the Sacramento and San Joaquin valleys
of central California and range
south to Santa Barbara County. They
do not wander outside of their normal
range as often as black-billed magpies,
but they have been found in extreme
northern California.
Habitat
Magpies are associated with the dry,
cool climatic regions of North
America. They are typically found
close to water in relatively open areas
with scattered trees and thickets. The
black-billed magpie inhabits foothills,
ranch and farm shelterbelts, sagebrush,
streamside thickets, parks, and
in Alaska, coastal areas. The yellowbilled
magpie inhabits farmlands,
stream groves, and areas with scattered
oaks or tall trees. Their range
coincides with a few species of mistletoe
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 renest if their first attempt
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 begin
as late as mid-June. The incubation
period is 16 to 18 days and young are
able to fly 3 to 4 weeks after hatching.
Young forage with the adults and then
join other groups in summer to form
loose flocks. Winter congregations
may include more than 50 individuals.
Yellow-billed magpies, though, may
form nightly roosts of 50 or more soon
after nesting.
Magpies are not swift fliers. They
elude predators and danger by flitting
in and out of trees or diving into heavy
cover. They usually stay near cover,
but often forage in open areas on the
ground. Like other corvids, magpies
walk with a strut and hop quickly
when rushed. They are found close
to water, using it for drinking and
bathing.
Damage and Damage Identification
Magpies have come into conflict with
humans in North America for quite
some time. Poisons were used extensively
in the 1920s and 30s to resolve
serious depredations and livestock
predation. During this time, magpie
populations were greatly suppressed.
Today, however, no toxicants are currently
registered and populations have
increased. Magpies cause a variety of
problems, especially where their numbers
are high. Most problems occur in
localized areas where loose colonies
have concentrated in close proximity
to humans.
An ear of corn damaged by a magpie
Magpies can cause substantial damage
locally to crops such as almonds, cherries,
corn, walnuts, melons, grapes,
peaches, wheat, figs, and milo. Their
damage is probably greatest in areas
where insects and wild mast are relatively
unavailable. Typically, other
birds such as blackbirds and robins
cause more damage to growers in fruit
orchards and grain fields because of
their greater abundance.
Magpies are often found near livestock
where they feed on dung- and carrionassociated
insects. They also forage for
ticks and other insects on the backs of
domestic animals. Perhaps the most
notorious magpie behavior is the picking
of open wounds and scabs on the
backs of livestock. If they find an open
wound, such as that from a new
brand, they may pick at it until they
create a much larger wound. The
wound may eventually become infected
and, in some instances, may kill
the animal. Magpies, like ravens, may
peck the eyes out of newborn or sick
livestock.
Magpies rob wild bird and poultry
nests of eggs and hatchlings. Typically,
that does not affect wild bird populations
except in local areas where limited
habitat makes nests easy to find.
They can be very destructive to poultry,
however, especially during the
nesting season when magpie parents
are gathering food for their young.
Magpie roosts can be a nuisance
because of excessive noise and the
odor associated with droppings. During
winter, magpies may congregate in
loose colonies and form nightly roosts
of hundreds after they have migrated
southward and to lower elevations.
They typically roost in dense thickets
or trees.
Legal Status
Magpies are protected as migratory
nongame 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.
Damage Prevention and
Control Methods
Exclusion
Exclusion is generally not feasible to
protect crops from magpie depredation
unless crops are of high value or
the area to protect is relatively small.
Nylon or plastic mesh netting can be
used to cover crops, but netting is
expensive and labor-intensive, making
it uneconomical to use in most situations.
Netting can be used to protect
individual trees and is most appropriate
in small areas where depredation is
extreme.
Exclusion is an ideal method to keep
magpies from livestock when it is
economical to do so. Poultry nests and
young kept in fenced coops and
feeding areas (maximum 1 1/2-inch
[3.8-cm] mesh) are relatively safe from
magpies. Lambing pens can reduce the
incidence of eye pecking. Livestock
with open wounds or diseases can be
kept in areas that exclude magpies
until they are healthy.
Habitat Modification
Predation on poultry often increases
during magpie breeding season. Raids
of increasing intensity can often be tied
to a few offending breeding pairs with
young. Removal of their nests can effectively
reduce predation. If removal
takes place early in the nesting season,
magpies may renest, often in a completely
new area.
Clear low brush to reduce nesting
habitat in areas where several blackbilled
magpies are regularly concentrated
and cause significant yearly
damage. This method reduces habitat
for all wildlife, however, and should
be carefully considered before undertaken.
Removing or thinning roost trees will
force magpies to find new roost sites.
The primary factor to consider is the
number of trees that need to be
removed to satisfactorily reduce cover
so magpies will relocate. Usually, the
removal of only a few trees will discourage
magpies.
Frightening
Frightening devices are effective for
reducing magpie depredations to
crops and livestock. Several methods
are used to frighten birds and are
explained in greater detail in the chapter
on Bird Dispersal Techniques in
this manual. A combination of human
presence, scarecrows, pyrotechnics
(fireworks), and propane cannons provide
a good frightening or hazing
program and can reduce depredations
significantly. The cost of using each of
these techniques must be compared to
determine the most effective combination
to obtain the greatest benefit-cost
ratio. The success of these devices varies
greatly with location, availability of
alternate food supplies (such as insects
and wild mast), and how the techniques
are used.
In a hazing program, the periodic presence
of a person is important because
it reinforces most techniques. The
mere presence of a person will normally
keep magpies at a distance,
especially where magpies have been
hunted.
Frightening devices such as scarecrows
and other effigies, eye-balloons,
hawk kites, and mylar (reflective) tape
are used to deter magpies. Most are
effective for only a short time, but their
effectiveness can be extended by moving
them regularly. The human scarecrow
is still one of the most effective
frightening devices. Painted eyes on
both front and back of the head and
arms made of flaps that blow in the
wind will increase its effectiveness.
Place scarecrows at regular intervals in
the threatened area (one for every 2 to
10 acres [1 to 4 ha]) along with a combination
of other frightening devices.
Pyrotechnics or fireworks can be used
to repel animals. These explode,
whistle, or scream after being ignited.
Typical pyrotechnics are shellcrackers,
rope firecrackers, and racket and
whistle bombs. These can be purchased
from suppliers, but some states
require a permit from the state fire
marshal. Shellcrackers are probably
the most widely used and are shot
from a 12-gauge shotgun, travel about
75 yards (70 m), and then explode. The
15 mm pistol launcher, however, is
more economical, easier to carry, and
allows reports and whistle and racket
bombs to be shot. The variety seems to
be more effective for magpies. The
projectiles travel from 35 to 70 yards
(30 to 65 m) depending on the style.
These can be shot whenever magpies
are seen in the damage area, but conservative
use will reduce acclimation.
Check state and local laws regarding
pyrotechnics.
Propane cannons fire loud blasts at
timed or random intervals. A variety
of styles are available. Conceal cannons
in threatened areas, move them
every 3 to 5 days, and use sparingly to
avoid habituation. For magpies, the
blast interval should be no greater than
one every 2 minutes and the interval
should be varied. Shooting a few magpies
with a shotgun and using pyrotechnics
will increase the effectiveness
of propane cannons.
Trapping
Trapping is effective in reducing local
magpie populations and damage
where they have concentrated in high
numbers because of food availability
or winter conditions. Several trap
designs have been successful in capturing
magpies. Traps made of weathered
materials are most successful, but still
require time for magpies to become
accustomed to them. Traps are most
effective in areas frequented by magpies
or along their flight paths into
damage areas. Consult federal, state,
and local laws before trapping.
An effective trap design commonly
used for capturing magpies is the
modified Australian crow trap (Fig. 2).
This is an inexpensive decoy trap that
becomes more effective after the first
birds (decoys) are caught. The standard
measurements in figure 2 can be
modified to facilitate transportation
and storage, but the dimensions of the
ladder openings or slots must remain
the same. The trap can also be built to
fit onto a trailer for transporting from
one site to another.
 The modified Australian crow trap has
been used effectively in Washington
and Oregon by baiting the trap with a
red-colored, dry dog food. Initially,
place dog food on the middle slat of
the ladder until the first magpies are
caught. Inside under the slots, place 10
pounds of dog food and water. Carrion,
such as a chicken carcass or a
road-killed rabbit, can also be used as
an attractant. Check the trap daily,
remove all but two magpies, and
replace bait and water as needed. Nontarget
birds that are captured should
be immediately released unharmed.
This trap can take several magpies, but
it does require some time and expense
to maintain properly.
Another trap design that has been successful
for trapping magpies in Alberta
is a circular-funnel trap (Fig. 3). Prebait
the area to be trapped. After magpies
start feeding, place the trap nearby
where they can adjust to it. To attract
magpies into the trap, place a line of
bait leading into it. After the first birds
are caught, remove all but one or two
decoys and any remaining prebait.
Keep trapping an area until most magpies
are caught and then move the trap
to a new location. This trap is probably
not as efficient as the crow trap for
catching large numbers of birds, but it
is not as cumbersome and may be
more effective at trapping magpies
prone to feeding on the ground.
Padded-jaw pole traps can also be
used to take a few offending magpies.
These are leghold traps, No. 0 or 1 coil
or jump spring, placed on 5- to 10-foot
poles that are erected in threatened
areas (Fig. 4). They can also be placed
on routinely used perches. Traps do
not have to be covered. The jaws need
to be well padded with foam rubber or
cloth and wrapped with electrician’s
tape to allow the leg to be snugly
caught without breaking it. Run a
heavy-gauge wire through the trap
chain ring and staple the wire to the
top and bottom of the post, allowing
magpies to slide to the ground and
rest. Both sides of the trap should be
anchored with fine wire or thread to
give the trap some stability. Other
perches that cannot have traps placed
on them should be removed or
covered with tack board or porcupine
wire to prevent magpies from landing.
Be sure to
check all laws regarding the use of
pole traps.
Shooting
Shooting can be an effective means to
eliminate a few offending magpies or
to reduce a local population. Shotguns
are recommended for shooting. Magpies
can be stalked or shot from blinds
under flight paths. They also can be
lured with predator calls. Magpies,
though, quickly become wary and
learn to avoid hunters. Shooting in
conjunction with a hazing program
provides greater control of damage
than does shooting alone. Consult
local, state, and federal laws on
shooting.
Economics of Damage
and Control
Magpies benefit agricultural producers
by consuming thousands of insects
and by scavenging, but they can also
have a negative local impact that can
turn severe. Losses are greatest where
nesting magpies are in close proximity
to poultry producers or concentrated
in numbers that constitute a problem.
Damage may increase dramatically
when wild mast and insects are relatively
unavailable.
Each producer in the range of magpies
should develop a management plan
before magpies become a problem.
Preparedness enhances the success in
decreasing depredation. The cost of
the different options for control should
be weighed and compared with the
success in controlling the problem.
Long-term solutions should be implemented
wherever possible, but be prepared
to take remedial control
measures when necessary. Prior to the
depredation season, an estimate of the
magpie population and the availability
of alternate food sources should be
determined to make preparations
accordingly.
*The above information was taken from a University of Nebraska Web site with
express permission of Stephen Vatassel, wildlife damage project coordinator.
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