Abstract # 2194 Event # 8:

Scheduled for Thursday, June 21, 2007 11:00 AM-11:15 AM: Session 1 (North Main Hall C/D) Oral Presentation

Is Satiation a Factor in Time of Retirement by Callitrichid Groups?

N. G. Caine
California State University San Marcos, Department of Psychology, San Marcos, CA 92096, USA
     Due to their pattern of early entrance to and late exit from the sleeping site, callitrichids go without eating for up to twelve hours or more. They may, therefore, delay entering the sleeping site until they have achieved a certain level of satiation, accounting for some of the variability in retirement times observed in both captive and wild groups. I observed two groups of Geoffroy’s marmosets (Callithrix geoffroyi) living out of doors at the Center for Research for Endangered Species, San Diego Wild Animal Park. For thirty days, all visits to the food pans during three different time periods were recorded. In addition, I recorded instances of eating by marmosets that entered, briefly exited, and then re-entered the sleeping box at retirement. Wilcoxon or resampling tests [a=0.05] were used to compare across conditions. All but one of the fourteen marmosets made more visits to food pans in the hour prior to retirement than they did earlier in the day. Furthermore, marmosets were more likely to eat during brief exits from the sleeping box than they were following resting episodes outside the sleeping box earlier in the day. These results suggest that decisions about where and when to retire may be influenced by satiety. This, in turn, has implications for ranging, foraging, and antipredator decisions by callitrichid groups.