Abstract
Behavioral plasticity can be described as the ability to adjust behavior depending on environmental information. We used a food-storing (caching) paradigm, during which individuals either ate or cached food under different conditions, to investigate whether they could adjust their caching behavior when observed by conspecifics and heterospecifics, and which cues they used to elicit these behavioral changes. We examined the location and number of caches made by two corvid species differing in sociality, highly social pinyon jays (Gymnorhinus cyanocephalus) and less social Clark’s nutcrackers (Nucifraga columbiana). Although pinyon jays cached a similar amount of food across conditions, they allocated more caches to areas less accessible to the observer. Nutcrackers, however, reduced the number of seeds cached when another nutcracker was present in comparison to when they cached alone. Both species relied on different social cues to elicit re-caching: pinyon jays responded to the amount of time the observer spent close to the caching locations, whereas nutcrackers responded to the amount of time the observer spent pilfering their caches. The differences in cache protection behaviors and the social cues eliciting them may be explained by the species’ social organization. Pinyon jays may only adjust their caching behavior when necessary, as they are often surrounded by other individuals. Clark’s nutcrackers reduce their caching when observed, as they have more opportunities to cache alone, and may resort to additional cache protection when experiencing pilferage. Overall, our results provide insight into understanding how pressures associated with the social environment may influence foraging behaviors.
Competing Interest Statement
The authors have declared no competing interest.
Footnotes
Author Note Alizée Vernouillet is now a Postdoctoral Researcher at the Department of Experimental Psychology at Ghent University.
AV and DMK developed the study; AV conducted the experiments and analyzed the data; AV wrote the manuscript with comments from DC and DMK.
Research support was provided by a University of Manitoba Graduate Fellowship and by a BOF postdoc fellowship (#BOF.PDO.2021.0035.01) to AV, and by a Natural Science and Engineering Research Council Discovery grant (#RGPIN/4944-2017) and Canada Research Chair to DMK. The authors are grateful to Iroshini Gunasekara, Thomas Rawliuk, and Nicole Tongol for helping with video scoring, and to Ben Farrar for his comments. Data are available as supplementary material. The experiment was not preregistered.
Previous analyses encompassed two approaches of model comparisons. New analyses only use a LRT approach. Focus of the paper has shift on a more ecological approach. Supplemental files also updated