Motivational control of caching behaviour in the scrub jay, Aphelocoma coerulescens

We investigated the motivational control of caching behaviour in scrub jays using a two-stage procedure to examine the effects of prefeeding and/or pr ecaching (stage 1) on subsequent caching behaviour (stage 2). Experiment 1 demonstrated that both prefeeding and precaching reduced the subsequent cac hing of both edible (peanuts) and inedible (stones) items. The reduction in caching was greatest when the items available for storing were the same in the two stages. This item specificity was confirmed in experiment 2 using two food types, peanuts and dog food kibbles. The final experiment demonstr ated that the effect of prefeeding on subsequent caching can also be food s pecific, in that birds that received food in a powdered form that they coul d eat, but not cache in stage 1, showed a reduction in subsequent,caching i n stage 2 only when the food type was the same in the two stages. These res ults suggest that caching behaviour is controlled by both the feeding syste m and an independent caching system, and that this control is mediated by t he incentive value of the specific items rather than by a general motivatio nal state. (C) 1999 The Association for the Study of Animal Behaviour.