Effects of experience and social context on prospective caching strategiesby scrub jays

Social life has costs associated with competition for resources such as foo d(1). Food storing may reduce this competition as the food can be collected quickly and hidden elsewhere(2-4); however, it is a risky strategy because caches can be pilfered by others(5-9). Scrub jays (Aphelocoma coerulescens ) remember 'what', 'where' and 'when' they cached(10-13). Like other corvid s(6-9,14), they remember where conspecifics have cached, pilfering them whe n given the opportunity, but may also adjust their own caching strategies t o minimize potential pilfering. To test this, jays were allowed to cache ei ther in private (when the other bird's view was obscured) or while a conspe cific was watching, and then recover their caches in private. Here we show that jays with prior experience of pilfering another bird's caches subseque ntly re-cached food in new cache sites during recovery trials, but only whe n they had been observed caching. Jays without pilfering experience did not , even though they had observed other jays caching. Our results suggest tha t jays relate information about their previous experience as a pilferer to the possibility of future stealing by another bird, and modify their cachin g strategy accordingly.