Black-billed Magpies

Pica hudsonia
Black-billed Magpies

Magpies are familiar to everyone living on the arid portions of the West. A relative of crows and jays, magpies live in meadows, grasslands and sagebrush plains of the West. Their nesting territories often follow stream courses. Though they like open areas and are not found in dense woods, they stay close to cover for protection from raptors. Magpies don’t avoid human development, often spending time near barnyards, livestock areas and grain elevators where they have ready access to food.

Speaking of food, magpies eat just about anything, a trait that often gets them at cross-purposes with people. They'll eat fruits and grains, grasshoppers and beetles, squirrels and voles. They sometimes find beetles by flipping cow dung. They raid other bird's nests. They steal meat from the kills of coyotes and other hunters. In fact, carrion is a main food source, as are the maggots found in the carrion. Magpies also land atop large animals, such as cows or moose, and pick ticks off them. In short, they'll eat almost anything and employ any sort of methods to find it.

Black-billed magpies mate for life. The pairs seem to choose a nesting site together (though sometimes they disagree and each begin building separate nests in different locations). The female initiates the pair bond by begging for food from the male, which begins courtship feeding. During courtship they also use a tail-spreading display. During breeding, the male stands guard near the female to reduce the chance she’ll mate with another male (which does occur).

Likewise, magpies share the work of nest building. The male gathers sticks for the exterior. The female tends to the interior, forming a mud cup and lining it with grass, in which she will lay anywhere from 1 to 9 eggs. They build their dome-shaped nests in trees, shrubs, utility poles, and even in deserted buildings. They will nest in open woodlands, riparian thickets, farm fields and suburban areas. The nests vary widely in size but are typically about 30 inches high and 20 inches wide.

On the wing, magpies make long, sweeping flights with white flashes of their wing patches and long, trailing tails. They perch at the tops of trees, which is a means of visually establishing their territory, the equivalent of other bird species' songs. Magpies walk with a swaggering strut. They sometimes gather in flocks, even seemingly living communally, and will band together to mob a raptor. In groups, males establish dominance through a stretch display, raising the bill in the air and flashing their white eyelids. They also show aggression with their wings, flickering or quivering them to display the white wing patches; and tails spreading, quivering, or flicking their elongated tail feathers.

One of the most notable black-billed magpie behaviors is the so-called "funeral." When one magpie discovers a dead magpie, it begins calling loudly to attract other magpies. The gathering of raucously calling magpies (up to 40 birds have been observed) may last for 10 to 15 minutes before the birds disperse and fly off silently.

 

Much of the text for this article was taken—often verbatim—from the Cornell Laboratory of Ornithology, with a little help from Wikipedia. 

Facts About Black-billed Magpies

Black-billed magpies are one of only 4 North American birds that have tails making up half (or more) of their body length, the others being the yellow-billed magpie, scissor-tailed flycatcher and fork-tailed flycatcher.

Historical records show that magpies have been associates of people for a long time. They frequently followed hunting parties of Plains Indians and fed on leftovers from bison kills. On their expedition, Lewis and Clark reported magpies boldly entering their tents to steal food.

Like most members of the jay family, black-billed magpies are a nest predator, although eggs and nestlings make up only a tiny portion of the bird’s overall diet.

The magpie makes a large nest that can take 40 days to construct, but only uses about 1% of the pair's daily energy. Laying eggs, on the other hand, takes 23% of the female's daily energy budget.

The magpie frequently picks ticks from the backs of large mammals, such as deer and moose. The magpie eats the ticks or hides some for later use, as members of the crow and jay family often do with excess food. Most of the ticks, however, are cached alive and unharmed, and may live to reproduce later.

The longest-living magpie on record was at least 9 years, 4 months old and lived in Idaho.