Perceptual specificity in the alarm calls of Gunnison's prairie dogs

Gunnison's prairie dogs have a complex alarm communication system. We show that the escape responses of prairie dogs to naturally occurring live predators differed depending upon the species of predator. We also show that playbacks of alarm calls that were elicited originally by the live predators produced the same escape responses as the live predators themselves. The escape responses fell into two qualitatively different categories: running to the burrow and diving inside for hawks and humans, and standing upright outside the burrow for coyotes and dogs. Within these two categories there were differences in response. For hawks, only the prairie dogs that were in the direct flight path of a stooping red-tailed hawk ran to their burrows and dove inside, while for humans and human alarm call playbacks there was a colony-wide running to the burrows and diving inside. For coyotes and coyote alarm call playbacks there was a colony-wide running to the burrows and standing alert at the burrow rims, while for domestic dogs and playbacks of alarm calls for domestic dogs the prairie dogs assumed an alert posture wherever they were feeding, but did not run to their burrows. These responses to both the live predators and to predator-elicited alarm calls suggest that the alarm calls of Gunnison's prairie dogs contain meaningful referential information about the categories of predators that approach a colony of prairie dogs.