Exploration and diet specialization in eastern chipmunks - Québec - Canada

Individual diet specialization (IDS) is widespread and can affect the
ecological and evolutionary dynamics of populations in significant ways.
Extrinsic factors (e.g., food abundance) and individual variation in
energetic needs, morphology, or physiology, have been suggested as drivers
of IDS. Behavioral traits like exploration and boldness can also impact
foraging decisions, although their effects on IDS have not yet been
investigated. Specifically, variation among individuals in exploratory
behavior and their position along the exploration/exploitation trade-off
may affect their foraging behavior, acquisition of food items and
home-range size, which may in turn influence the diversity of their diet.
Here we analyzed stable carbon and nitrogen isotopes in hair of wild
eastern chipmunks, Tamias striatus, to investigate the influence of
individual differences in exploration on IDS. We found that exploration
profile, sex, and yearly fluctuations in food availability explained
differences in the degree of dietary specialization and in plasticity in
stable carbon and stable nitrogen over time. Thus, consistent individual
differences in exploration can be an important driver of within-population
niche specialization and could therefore affect within-species
competition. Our results highlight the need for a more thorough
investigation of the mechanisms underlying the link between individual
behavioral differences and diet specialization in wild animal populations.