Boldness and niche width structure spatial interactions in a natural rodent community.

Consistent among-individual differences in behaviour can influence how individuals distribute in and use space, and thus influence competition within and between species, with potential consequences for species coexistence. These behavioural traits help characterize ecological niches, particularly under varying intensities of interspecific competition. While previous work examined behavioural type-dependent spatial interactions between pairs of ecologically similar species, here we extend those analyses to a full multi-species community context, including newly analysed species. In a natural rodent community of four co-occurring species, we tested whether boldness predicts space use and spatial interactions within and across species of varying ecological similarity. Boldness covaried positively with core area and home range size across all species, indicating consistent behavioural type-dependent differences in space use. In contrast, microhabitat use and neighbour density showed little association with boldness. Evidence for personality-dependent spatial structuring emerged primarily in metrics capturing spatial proximity and ecologically similar encounters, suggesting that behavioural effects on interactions are context dependent, being most evident among ecologically similar competitors and in distance-based measures of spatial interactions. Overall, our results suggest that boldness is most clearly linked to how individuals use space, whereas effects on spatial encounter structure within the community are weaker and appear to differ between the relatively more generalist and more specialist species in the community with respect to habitat use and diet. These findings support the idea that behavioural type-dependent space use can contribute to individual niche differentiation and may influence how potential interactions are distributed within ecological communities.