Are Cape Ground Squirrels ( Xerus inauris) Sensitive to Variation in the Pay-offs from Their Caches?

For food caching to be adaptive, the benefits of recovery must outweigh the costs of storing an item. One of the costs to cachers is the risk of theft, and therefore, it is predicted that individuals may be sensitive to this theft and show various behavioural strategies to minimise it. In this study, we gave wild Cape ground squirrels ( Xerus inauris) a choice between two different coloured items of the same food type: one item with a specific colour that was always artificially removed when cached and the other item with a different colour that was not removed when cached. During the choice presentations, subjects reduced the amount they consumed and cached of the food items with the colour that was experimentally removed when cached, despite the two items only differing in caching pay-off. This avoidance to choose the food with the colour that was removed occurred over time, which suggests that subjects were using information about the item's pay-off during cache recovery and this then impacted on successive decisions. This study highlights how the sensitivity to a food item's pay-off can affect an individual's choice towards items that offer the greater overall reward. [ABSTRACT FROM AUTHOR]