It's a sure bet that the person who coined the term "birdbrain" never dealt with a magpie.
Tim Birkhead, emeritus professor of zoology in the department of animal and plant sciences at the University of Sheffield, Great Britain, is author of the book "The Magpies: The Ecology and Behaviour of Black-Billed and Yellow-Billed Magpies." Birkhead has studied both species in the field, in Europe and the United States, and notes that people who deal with magpies on a regular basis have a keen understanding of how smart they are.
"Every gamekeeper will tell you how clever magpies are — avoiding people carrying a gun — as if they know," he says, via email. "The magpies' most impressive trait is knowing themselves in a mirror. Very few animals can do this. Magpies can also be taught to speak. They hide food and can relocate hidden food with incredible accuracy."
With regard to their intelligence, magpies are very much like fellow corvids – jays, rooks, ravens and crows, says Walt Koenig, a senior scientist with the Cornell Lab of Ornithology. Koenig has studied magpies in the past and is currently studying the social behavior of acorn woodpeckers and patterns of acorn production in California oaks in the Carmel Valley of California. (It also happens to be the only place in the world where yellow-billed magpies live.)
"For a time, yellow-billed magpies were the only North American bird that was endemic to a single state in the continental United States," says Koenig. "A yellow-billed magpie has never found its way over the Sierras (Sierra Nevada mountain range) into the Great Basin. Any magpie you see on the east side of the Sierras is always a black-billed magpie. And I don't know if there's ever been a black-billed magpie on the west side of the Sierras. Yellow-billed magpies don't make it up past the Cascade Range. They're purely in the Central Valley and they come out here toward the coast in a few of the larger valleys."
The yellow-billed variety is described as a year-round, sociable bird. They nest in pairs by the dozens fairly close to each other — within hundreds of yards. In one colony Koenig and other researchers studied, they found 15 to 20 nests in one canyon.
"We referred to yellow-billed magpies as semi-colonial," says Koenig, "They make big domed stick nests with entrances on the sides that can be a couple of feet across. The nests sometimes end up in mistletoe clumps which made them hard to find sometimes."
It appears that both yellow- and black-billed magpies are monogamous and mate for life. Magpie pairs build their nest together, the male gathering sticks for the exterior while the female works on the interior, lining it with mud and grass. The female lays a clutch of eggs (the number varies according to species), usually one brood per year.
Their plumage is eye-catching — black and white overall with black and blue-green iridescent flashes on their wings and tail. Their wings are short, but their tails are long — as long or slightly longer than the rest of their bodies. Their bills are strongly pronounced, like a crow's and — true to their name — either yellow or black. They are typically between 17 inches (45 centimeters) and 23 inches (60 centimeters) in length and weigh 5 pounds (2 kilograms) to 7 pounds (3 kilograms). The average magpie wingspan is 22 inches (55 centimeters) to 24 inches (61 centimeters).
The Magpie Diet
Magpies are what scientists call opportunistic eaters. In other words, you might see a magpie eating carrion, but it probably makes up only a small amount of their diet.
"They're mostly out there foraging among the grass, eating insects and other stuff they can find," says Koenig. "But they will eat small mammals."
Magpies do have a couple of unique behaviors of note.
"They're one of the few animals that are known to have funerals," says Koenig. "Nobody really knows what's going on but when magpies find even parts of a dead magpie lying around because it got eaten, or died, a bunch will come together and start squawking. They recognize this dead bird as one of their own, and it sends them into this tizzy. They're obviously doing something. The general consensus is that they're social enough that when they see a dead magpie, they want to know who it, was how it affects them and how it affects the social stratification of the group."
The second is a behavior Birkhead calls "testing the locks," a sort of ceremonial gathering in the spring.
"Noisy clusters of up to 20 magpies in the trees chasing and calling," he says. "Our research showed that these are triggered by dominant members of the nonbreeding flock invading the territory of established pairs. Essentially, they are testing the locks — 'could I break in and take over if I push hard enough?' This is how some young magpies get territories and how some old ones lose theirs."
Why the Bad Rap?
Literature, from folktales to nursery rhymes, have demonized magpies as birds that swoop in to steal shiny objects or are harbingers of doom. But Birkhead says it's probably a combination of bad press and familiarity breeding contempt.
"If magpies were rare everyone would rave about their stunning white and 'black' iridescent plumage; their long tail and perky manner," Birkhead says. "They've become more common in the U.K. in the last 50 to 60 years and anything common can be perceived as a pest. Magpies take songbird eggs and nestlings, and understandably, people hate them for this. But sparrowhawks take many more, but do so 'invisibly' so are less maligned. And domestic cats take many more still. Gamekeepers call magpies 'vermin' — and that tag seems to make people think they can be abused with impunity. Gamekeepers catch magpies in Larsen Traps — a pretty inhumane way to control anything.
The increase in magpies coincided with the general decrease in songbirds and people put two and two together and made 10. Our research revealed no causal link between the two. Magpies do take songbird eggs and chicks, but so do lots of other predators, and small birds have evolved to cope with this and produce replacement clutches."