IT IS HIGH NOON IN A NO-NAME TOWN. A tall stranger ambles through the deserted streets, aware of watching eyes. He knows what the locals are saying. Yesterday they called him Big Man. Now, though, they have changed their tune. "It's the same dork," they buzz. "He's, like, totally harmless."

All this dialogue is guaranteed verbatim—but only if Prof. Con Slobodchikoff is correct in his translations of the squeaking, chittering sounds that prairie dogs use to communicate. "Here's an animal that is a lowly rodent and yet seems to have language with these complicated structures," says Slobodchikoff, 53, a biology professor at Northern Arizona University who has spent nearly 10 years studying a one-acre prairie dog colony near Flagstaff, observing the residents and recording their sounds. "It is possible that other species have languages of their own."

The son of Russian emigré parents, Slobodchikoff, who was born in Shanghai and moved to San Francisco in 1949, traces his fascination with language to the culture shock of trying to decipher U.S. newspaper headlines as a youngster. "I remember reading one that said, 'Giants Stomp Cincinnati,' " he says. "I wondered what kind of country we had come to." His interest in prairie dogs, on the other hand, started in '86: "They are, after all, right in my backyard."

By converting the prairie dog sounds he records to sonograms, and using a computer to correlate them with observations of events happening at the time, Slobodchikoff claims to have identified about 50 words. Prairie-dog lingo, he says, can distinguish colors, shapes and sizes, as well as tell a coyote from a German shepherd and a man from a woman. "The more dangerous they perceive an animal to be," he says, "the more individuals chime in."

Does Slobodchikoff's work have any real-world use? "With the aid of computers we may one day be able to communicate with other animals," he says. "Like reason with your Jack Russell who pees on the furniture."