"researchers who study gray squirrels argue that their subject is far more compelling than most people realize, and that behind the squirrel’s success lies a phenomenal elasticity of body, brain and behavior."
Gray squirrels use their sharp, shaded vision to keep an eye on each other. Michael A. Steele of Wilkes University in Pennsylvania and his colleagues have studied the squirrels’ hoarding behavior, which turns out to be remarkably calculated and rococo. Squirrels may be opportunistic feeders, able to make a meal of a discarded cheeseburger, crickets or a baby sparrow if need be, but in the main they are granivores and seed hoarders. They’ll gather acorns and other nuts, assess which are in danger of germinating and using up stored nutrients, remove the offending tree embryos with a few quick slices of their incisors, and then cache the sterilized treasure for later consumption, one seed per inch-deep hole.
But the squirrels don’t just bury an acorn and come back in winter. They bury the seed, dig it up shortly afterward, rebury it elsewhere, dig it up again. “We’ve seen seeds that were recached as many as five times,” said Dr. Steele. The squirrels recache to deter theft, lest another squirrel spied the burial the first X times. Reporting in the journal Animal Behaviour, the Steele team showed that when squirrels are certain that they are being watched, they will actively seek to deceive the would-be thieves. They’ll dig a hole, pretend to push an acorn in, and then cover it over, all the while keeping the prized seed hidden in their mouth. “Deceptive caching involves some pretty serious decision making,” Dr. Steele said. “It meets the criteria of tactical deception, which previously was thought to only occur in primates.”
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