The incentive value of a natural and cognitively demanding behaviour: food-caching jays as a model system

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The overall objective of this research is to study how inherently rewarding it is for an animal to perform a natural and cognitively demanding behaviour. The behavior that we will study is one that jays do for a living, namely hiding food for future consumption and relying on memory to find hidden stashes at a later date ('food-caching'). From a welfare perspective, there is increasing interest in using cognitive enrichment for captive animals (i.e. providing them with tasks that are mentally challenging), but there is a lack of scientific evidence as to whether and how cognitive activities are rewarding to animals per se. The proposed studies directly address this issue by investigating what aspects of caching behaviour the jays are most motivated to perform (i.e. the jays value the most), and how these decisions are influenced by the cognitive attributes of the behaviours, such as the jays' knowledge of the likelihood of successful recovery, and the bird's current or anticipated motivational state. To address these issues, we shall develop a decision paradigm for the jays in which the choice between two perches determines access to one of two cages. The jays will be given a choice between differing numbers of cache locations in these cages to find out whether their preference for the opportunity to cache is enhanced by how hungry they are, and whether the value they place on caching also depends on whether or not they have been prevented from caching either recently, or over longer time periods. We shall also investigate whether the birds' choices are also modulated by what happens when they come to recover their caches. This is important because in order for the recovery conditions to affect the jays' caching preferences, the birds must anticipate these conditions on the basis of their past experience of recovering their caches. To test this idea, we shall determine whether or not jays assign a higher value to caching in places from which they have the opportunity to recover and whether they assign a lower value to caching a type of food that has previously been stolen or has become spoiled. We shall also ask whether the opportunity to cache is affected by their feeding motivation at the time when they cache or when they come to recover the caches, and whether they value caching in private more than when others jays are present who could witness the caching event and therefore pose a threat to their caches. Taken together these experiments will provide important information about the caching decisions that jays make and the extent to which these decisions are influenced by cognitive and motivational factors. It will thus reveal how rewarding performance of this natural behavior is under different motivational and cognitive conditions that influence the outcome of caching behavior. By providing new information about the value of performing a cognitively demanding task, the project will allow us to investigate the rationale and potential for using 'cognitive enrichment' in welfare enhancement programmes.