Meeting Abstract
Ecological range expansions occur when a species expands its geographic distribution and they are thought to be increasing in frequency due to rapid environmental change. Although shifts in the distribution of species may have important ecological and evolutionary consequences, less is known about the characteristics of individuals leading range expansions in addition to those traits contributing to the success of individuals that disperse to these new areas. Some studies have suggested that specific behavioral attributes may cause some individuals to be more likely to participate in range expansions or be more successful either during the range expansion or after they arrive to the novel area. During a 3-year field study, we characterized the behavior of white-footed mice (Peromyscus leucopus) along a range expansion gradient throughout Michigan by sampling populations of P. leucopus that differ in time since colonization. We used standardized behavioral trials to characterize their behavior (activity, exploration) and stable isotope analyses to quantify their dietary breadth. As a control group, we also quantified the behavior and diet of a congeneric species, deer mice (Peromyscus maniculatus), at each of our study sites along the range expansion gradient where they were available. Using these data, we examined if the behavior and isotopic niche of the range-expanding species (P. leucopus) was affected by time since colonization and if they differed from the resident species (P. maniculatus). We discuss our results in the context of other studies examining if dispersal is dependent upon animal personality and those examining if an “invader behavioral syndrome” exists.
