Air Date: Week of November 30, 2001

Living on Earth's Maggie Villiger reports that in the thieving world of scrub jays, it takes one to know one.

Transcript

CURWOOD: Just ahead, sex and science, on magazine covers and in coral reefs. First, this page from the Animal Notebook, with Maggie Villiger.

VILLIGER: Thieves are said to be among the most paranoid people around. After all, they suspect others of just the sorts of nefarious deeds they themselves carry out. Now, new research on scrub jays shows that thieving birds are also more distrustful than their law-abiding neighbors. Like most animals, scrub jays must compete for limited resources such as food, and one way to deal with the competition is to quickly collect what's available and stash it away for a rainy day. But there's the risk a neighbor might raid your larder before you return to claim its contents. So most birds move their food stash from one location to another, to avoid it being stolen. Scientists designed an experiment to figure out why. They positioned the jays so other jays could watch while they hid their loot. When they took the watcher birds away, the hiders would re-stash their food in new places. It turns out that the birds most intent on re-hiding their caches were the ones that had themselves pilfered in the past. Robber birds seemed to assume others shared their own criminal tendencies. In the thieving world of jay birds, it takes one to know one. That's this week's Animal Note. I'm Maggie Villiger.

CURWOOD: And you're listening to Living on Earth.