Scatterhoarding is a time‐ and energy‐intensive behavior where animals store food in their home ranges for consumption in a season of scarcity, typically winter. Due to the costs of this behavior, scatterhoarders should hoard the food that they need to survive during an extreme period of food‐scarcity to benefit from at a later date. We used a citizen science program to examine geographic patterns in the scatterhoarding behavior of eastern gray squirrels Sciurus carolinensis . We hypothesized that squirrels would exhibit variation in scatterhoarding behavior due to the differing winter conditions experienced at different latitudes, which should impact the demand for stored food over winter, and hence the necessity and benefit of hoarded food. This should result in more scatterhoarding behavior in regions with harsher winters. We recruited over 750 volunteers throughout the eastern United States to collect observational data on scatterhoarding activity of eastern gray squirrels during 4 years (2019–2022). We used the United States Department of Agriculture Plant Hardiness Zones as an index of winter conditions experienced by eastern gray squirrel populations in different parts of the species' range. Volunteers conducted 4540 10‐min observations of squirrel behavior across 12 plant zones. We applied hurdle models to estimate the effect of period of the year and plant zone on scatterhoarding behavior. We found that the frequency of scatterhoarding behaviors (including caching, recaching, and eating recovered food) observed during the fall increased significantly as plant zone decreased, indicating that squirrels in areas with harsher winter conditions invested more time in building a supply of hoarded food. However, we found that even in areas with virtually no winter conditions (e.g. south Florida, USA), squirrels still engaged in some scatterhoarding behavior. Our findings suggest that scatterhoarding may be a more important behavior as one moves north, and squirrels encounter harsher winters.
Ramirez et al. (Wed,) studied this question.