Department of Psychology, University of California, Davis, California 95616, U.S.A.
Alarm Calls of California Ground Squirrels (Spermophilus beecheyi)
Article first published online: 26 APR 2010
1978 Blackwell Verlag GmbH
Zeitschrift für Tierpsychologie
Volume 46, Issue 1, pages 58–70, January-December 1978
How to Cite
Owings, D. H. and Virginia, R. A. (1978), Alarm Calls of California Ground Squirrels (Spermophilus beecheyi). Zeitschrift für Tierpsychologie, 46: 58–70. doi: 10.1111/j.1439-0310.1978.tb01438.x
- Issue published online: 26 APR 2010
- Article first published online: 26 APR 2010
- April 4, 1977; May 6, 1977
California ground squirrel alarm vocalizations were recorded in field and laboratory, and sonagraphically analysed. The contexts of both naturally occurring and experimentally elicited calls were noted in the field. The components of this graded system are chatters, chats and whistles. Chatters and chats are often elicited by terrestrial predators, whistles commonly by low flying raptors. Whistles are more commonly associated with cryptic behavior and flight than chatter-chats, but both call types usually elicit bipedal alert postures. These calls grade along a number of dimensions which may signal redundantly the level of excitation of the caller. We propose that the chatter-chat calls of highly aroused squirrels are composed of more and longer notes, occur at a higher rate, are less noisy and contain more frequency modulation. Whistles, however, are single-note calls that contain no frequency modulation, even though they are emitted by highly aroused squirrels and are long and noise free. Preliminary data suggest that: 1) chats are easier for a human ♀ to localize than whistles; 2) elevation of the head, by adopting bipedal postures and mounting promontories, enhances the audibility of alarms.