Caching at a distance: a cache protection strategy in Eurasian jays

Abstract

A fundamental question about the complexity of corvid social cognition is whether behaviours exhibited when caching in front of potential pilferers represent specific attempts to prevent cache loss (cache protection hypothesis) or whether they are by-products of other behaviours (by-product hypothesis). Here, we demonstrate that Eurasian jays preferentially cache at a distance when observed by conspecifics. This preference for a ‘far’ location could be either a by-product of a general preference for caching at that specific location regardless of the risk of cache loss or a by-product of a general preference to be far away from conspecifics due to low intra-species tolerance. Critically, we found that neither by-product account explains the jays’ behaviour: the preference for the ‘far’ location was not shown when caching in private or when eating in front of a conspecific. In line with the cache protection hypothesis we found that jays preferred the distant location only when caching in front of a conspecific. Thus, it seems likely that for Eurasian jays, caching at a distance from an observer is a specific cache protection strategy.Electronic supplementary materialThe online version of this article (doi:10.1007/s10071-016-0972-7) contains supplementary material, which is available to authorized users.

Eurasian jays do not copy the choices of conspecifics, but they do show evidence of stimulus enhancement

“…Previous experiments have indicated that Eurasian jays do attend to social context in caching and mate provisioning (Shaw & Clayton, 2012; Shaw & Clayton, 2013; Ostojić et al, 2013; Shaw & Clayton, 2014; Ostojić et al, 2014; Legg, Ostojić & Clayton, 2016). It is therefore still possible that jays use social information, but not for copying others’ choices, as none of the previous experiments required the birds to copy a demonstrator.…”

“…They also adjust their behaviour appropriately depending on whether they are caching or pilfering (Shaw & Clayton, 2014), and whether they compete with a dominant or subordinate (Shaw & Clayton, 2012). Furthermore, they prefer to cache out-of-sight behind an opaque barrier and at a distance when observed by conspecifics (Legg & Clayton, 2014; Legg, Ostojić & Clayton, 2016). During the breeding season, males are attentive to which foods their mates might prefer based on how much of which foods she has already eaten (Ostojić et al, 2013; Ostojić et al, 2014).…”

Peer Review #2 of "Eurasian jays do not copy the choices of conspecifics, but they do show evidence of stimulus enhancement (v0.1)"

“…Previous experiments have indicated that Eurasian jays do attend to social context in caching and mate provisioning (Shaw & Clayton, 2012;Ostojić et al, 2013;Ostojić et al, 2014;Legg, Ostojić & Clayton, 2016). It is therefore still possible that jays use social information, but not for copying others' choices, as none of the previous experiments required the birds to copy a demonstrator.…”

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“…Previous studies have indicated that Eurasian jays do attend to social context in caching and mate provisioning (Shaw & Clayton, 2012;Ostojić et al, 2013;Ostojić et al, 2014;Legg, Ostojić & Clayton, 2016). It is therefore still possible that jays use social information, but not for copying others' choices, as none of the previous studies required the birds to copy a demonstrator.…”

“…They also adjust their behaviour appropriately depending on whether they are caching or pilfering , and whether they compete with a dominant or subordinate (Shaw & Clayton 2012). Furthermore, they prefer to cache out-of-sight behind an opaque barrier and at a distance when observed by conspecifics Legg, Ostojić & Clayton, 2016). During the breeding season, males are attentive to which foods their mates might prefer based on how much of which foods she has already eaten (Ostojić et al, 2013;Ostojić et al, 2014).…”