Social behavior and response to predators in California ground squirrels (Spermophilus Beecheyi)

Seven California ground squirrels (Spermophilus beecheyi) were captured, introduced into a large, outdoor enclosure and observed over one year's time. In addition to observing social behavior, I conducted an experiment to determine the squirrels' responses to two-dimensional models, of varying shapes and sizes, moving above them. Comparing responses of squirrels to all aerial models together and to a control sound, I found that males responded more frequently to models than to noise alone. Females, on the other hand, responded to models and the control sound at about the same frequency. Within the social group males were typically dominant to females. There was an inverse relationship between dominance and frequency of occurrence of alert behaviors. Thus females were more often the sentinels. Nose-to-nose contact and approahces, considered greeting behaviors, occurred primarily between juveniles. Adults did greet other adults, but rarely greeted a juvenile squirrel. During many agonistic encounters tail flicking was commonly seen. Subordinate squirrels usually did the flicking. I conclude from this that tail flicking is an indication of tension, and perhaps a sign of subordination. (See more in text.)