Feather Files: Bird-Brained Criminals

The smarter birds are, the meaner they are

• Hannah Schardt
• Apr 01, 2008

The Findings: Brains, not brawn, determine which birds turn to theft to feed themselves and their young.

The Back Story: Snatching food foraged by others, known as kleptoparasitism, is a well-documented behavior among birds. But some bird families--including falcons and eagles--are far more inclined to steal than others, according to a new analysis published in Animal Behaviour. Researchers in Canada and Spain analyzed 856 reports of avian food theft from the scientific literature and found that, while a large body does not correlate with thieving behavior, a big brain does. Only 197 out of the 9,672 known bird species have been observed swiping food, and those species tend to be criminal masterminds--with big brains for their body size--rather than thugs.

The Big Picture: The association between kleptoparasitism and larger brains indicates that the ability to snag food from rivals may stem from greater cognition, not aggressiveness. In other words, for birds, stealing is the smart thing to do.