Crows by Candace Savage

often in snow or dirt, and only the bird that hid the food knows where to find it—with one critical exception. If another raven happens to be watching, it too will mentally map the spot, intent on sneaking back and stealing the reward.

    ➣ Nature red in tooth and claw—a raven pecks at a moose that was injured by a pack of wolves in Denali National Park, Alaska.

    SILVERSPOT’S TREASURES

    FROM WILD ANIMALS I HAVE KNOWN, BY ERNEST THOMPSON SETON, 1898
     
    O ne day while watching I saw a crow crossing the Don Valley [in Toronto] with something white in his beak. He flew to the mouth of the Rosedale Brook, then took a short flight to the Beaver Elm. There he dropped the white object, and looking about gave me a chance to recognize my old friend Silverspot [an old crow that could be recognized by a white patch on the side of his face]. After a minute he picked up the white thing—a shell—and walked over past the spring, and here, among the docks and the skunk-cabbages, he unearthed a pile of shells and other white, shiny things. He spread them out in the sun, turned them over, lifted them one by one in his beak, dropped them, nesting on them as though they were eggs, toyed with them and gloated over them like a miser. This was his hobby, his weakness.... His pleasure in them was very real, and after half an hour he covered them all, including the new one, with earth and leaves, and flew off. I went at once to the spot and examined the hoard; there was about a hatful in all, chiefly white pebbles, clamshells, and some bits of tin, but there was also the handle of a china cup, which must have been the gem of the collection. That was the last time I saw them. Silverspot knew that I had found his treasures, and he removed them at once; where I never knew.

    This interaction, in which the parties stand to profit by deceiving one another, provides a perfect natural laboratory for studying the mind of the trickster. If ravens really do attempt to outwit one another in this game of hide-and-seek, then both parties should be expected to behave strategically. On one side of the equation, for instance, a bird with food to hide might fly away from the crowd before burying its treasure or slip behind a boulder, where it knows it can’t be observed. And if, despite these maneuvers, it happens to catch another raven looking, it should dig up its cache and relocate it to a new and more secure location. Sure enough, in experiments by Heinrich and his colleagues—notably, Austrian zoologist Thomas Bugnyar—caching ravens have been found to employ all these tactics. What’s more, ravens have also been known to make “false caches” by going through all the motions of caching in front of other birds and then, when the would-be thieves rush in, carrying the food away to hide it in private.
    On the other side of the equation, the larcenous observers have a trick or two of their own. Rather than rushing up to see what the cacher is doing, they act casually and keep a little distance apart, as if they had no interest in what was going on. All the while, however, they are surreptitiously maneuvering to keep their sightlines clear and pinpoint the location of the hidden food. And even after the cache has been completed and the cacher leaves (with many an anxious backward glance), the observers maintain their undercover surveillance. A minute passes, two minutes. Finally, when the cacher seems to have cleared the area, the would-be thieves dash in, in an attempt to empty the cache before its rightful owner can come rushing back.

    ➣ Crows feast on the remains of the unfortunate John Stevens, who in 1635 was hanged, drawn, and quartered for treason.

    When Thomas Bugnyar published these findings in Animal Behaviour in 2002, he suggested that, based on his observations of caching both in the laboratory and the field, ravens appear to mislead each other intentionally. Yet he still couldn’t entirely exclude the possibility that the birds