Bird burglars listen for loot
Eurasian jays are tricky thieves. They eavesdrop on the noises that other birds make while hiding food in order to steal the stash later, new research shows. Scientists trying to figure out if the jays (Garrulus glandarius) could remember sounds and make use of the information placed trays of two materials—either sand or gravel—in a spot hidden from a listening jay’s view. Other avian participants of the same species, which were given a nut, cached the treat in one of the two trays. Fifteen minutes later, the listening bird was permitted to hunt up the stash (video). When food lay buried in a less noisy material such as sand, jays searched randomly. But if they heard gravel being tossed around as treats were hidden, they headed to the pebbles to pilfer the goods. Previous studies have shown that jays—like crows, ravens, and other bird burglars that belong to the corvid family—can remember where they saw food being hidden and return to the spot to look for the cache. But these new results, published in Animal Cognition this month, provide the first evidence that these corvids can also recollect sounds to locate and steal stashes of food. In their forest homes, where birds are heard more often than they are seen, this sneaky strategy might give eavesdropping jays a better chance at finding hidden feasts.