Crows Are Bandits, But Know Thier Own Kind

With neither a brilliant plumage nor a melodic song to set it apart from other birds, the crow might seem to have been dealt a low blow.

Instead of whistling a happy tune, crows cackle and squawk in irritating patterns that are about as charming as fingernails on a blackboard.

But animal behaviorists have long believed that the crow has at least one thing in its favor. It is among the most intelligent birds in the world, with some species so advanced that they make and store their own tools to extract food from hard-to-reach sources, such as holes in trees.

So with an IQ roughly equivalent to that of the family pooch, the crow's image should be looking up. But now comes new research that gives the crow another black eye, so to speak.

It turns out that while there is a little gray matter in its head, there is a lot of larceny in its soul.

Stealing, Not Protecting

According to animal behaviorists Renee Robinette Ha and James Ha of the University of Washington, some crows just can't keep their claws out of their neighbor's lunch box.

That may not seem all that surprising to anyone who has watched a flock of crows feeding on a beach and fighting among themselves, but it flies in the face of conventional wisdom about what the crows are really up to. While they are feeding, some crows constantly dash around the area, keeping watch for predators that might want to eat crow.

It is a form of vigilance, according to crow literature, with some crows assigned the task of watching out for enemies.

But the researchers have come up with data that shows that's not what the crows are doing. Instead of watching out for predators, those crows that are flying around and looking so vigilant are really just looking for something that they can steal from another member of the flock.

"It's not to protect them from predators," says James Ha, a research associate professor of psychology. "What we are showing is the vigilance, contrary to many studies, is primarily for food stealing."

"Finding that chance to steal food is a very uniform strategy among these birds," adds Renee Ha.

Those who were "guarding" the flock, for example, often swept down and took food away from other crows instead of watching out for enemies. And during high tide, when the crows were forced closer to a nearby forest where predators abound, no crows were manning battle stations. They just sat around, the researchers conclude, because nobody else had any food to steal.

The first of several studies conducted by the researchers was published in a recent issue of the journal Animal Behavior, but they have since carried their work to a "new level," as James Ha put it.

Good Crows and Bad Crows

It all began a few years ago when a graduate student, Renee Robinette, arrived on the Seattle campus with a yen to study complex behavior among birds. Her faculty adviser, James Ha, suggested they head for the beach. To study birds, of course.

Anyway, over the course of 18 months, Robinette spent about 300 hours sitting on the beach, cloaked in cold-weather gear, watching crows.

Robinette and her adviser captured a bunch of crows by using tranquilizer bait. Blood samples were taken from each bird for DNA research, and the birds were banded with color-coded leg bands so each could be identified during the study.

Robinette focused on one bird for five minutes, logging every activity, and then she moved on to another bird, a process she repeated thousands of times. The beach turned out to be a perfect place for observing the birds, because the forest was some distance away, allowing a clear view of the birds' activities.

Here's what she found:

Some of the birds were honest as Abe, but most were real bandits.

"We discovered that some of the birds never scrounge, and never steal," James Ha says. "They walk along and they find their own food. They may have it stolen from them, but they never steal."

But the bandits had a very different lifestyle, stealing roughly 65 percent of the time.

"We never had a bird that lived only by stealing, but we had birds that spent most of their time trying to steal," he adds. "It's pretty much how they are making their living."

It remains a mystery why some of the birds were honest while other members of the flock were corrupt.

"We have no idea" why that should be the case, Ha says.

"So we have tried to take it to a different level," he adds. "It's the most controversial."

Knowing Their Own Kind

Robinette set out to identify genetic markers in the blood samples taken from the crows in an effort to determine the relationship among the birds. Those markers, she hoped, would tell her if crows were stealing from their immediate relatives, or from their more distant relatives in the flock.

What she learned was quite surprising, and potentially of major importance, if the early findings are correct.

The bandits engaged in two types of theft — passive and aggressive. In some cases, the thief just walked casually up to a bird with a morsel, and the victim dropped the food and walked away. In other cases, however, the bandit squawked and chased its victim until the bird dropped the food.

The crows tended to be passive when stealing from birds to whom they were closely related, and aggressive toward their non-relatives.

"That seems to imply that they can recognize relatives from non-relatives," Ha says.

That would suggest that the birds are engaged in very complex social behavior patterns indeed.

And it would add another footnote to the legacy of the family Corvidae, which includes crows, ravens, jays and magpies. According to Kevin McGowan, a Corvid expert at the Cornell Laboratory of Ornithology, these birds have rivaled monkeys in some psychological tests. Ravens and magpies are believed to be able to count up to seven, and the crows of the Northwest drop shellfish onto hard surfaces to break them.

Perhaps most intriguing, McGowan says, the New Caledonian crow of the South Pacific makes complicated tools out of leaves and twigs to probe holes in trees for food. Then it stores the tools for later use.

The crows studied by the University of Washington team didn't go that far, but it turns out the crows weren't the only ones engaged in complex behaviorial patterns on the beaches north of Seattle over the past few years. Robinette and Ha were married last March.

Lee Dye’s column appears weekly on A former science writer for the Los Angeles Times, he now lives in Juneau, Alaska.