Asocial free-ranging squirrels: Bolder individuals maintained larger core areas than shyer individuals; more proactive and sociable personality types had greater access to a preferred resource

Bridging animal personality with space use and resource use in a free-ranging population of an asocial ground squirrel. Jaclyn R. Aliperti et al. Animal Behaviour, September 10 2021. https://doi.org/10.1016/j.anbehav.2021.07.019

Highlights

• Bolder individuals maintained larger core areas than shyer individuals.

• More active and bolder individuals moved faster under natural conditions.

• More proactive and sociable personality types had greater access to a preferred resource.

• Among-individual variation in activity and sociability was positively correlated.

• Our data support personality-dependent use of space and resources in nature.

Abstract: Consistent individual differences in behaviour, or personality, likely influence patterns of space use and resource use in wild animals. However, studies on personality-dependent space use in natural ecosystems remain rare due to the difficulty of obtaining paired data sets on spatial dynamics and repeated personality measures from marked animals. We used repeated standardized assays (open field, mirror image stimulation, flight initiation distance and behaviour in trap) to perform the first characterization of personality in a free-ranging population of golden-mantled ground squirrels, Callospermophilus lateralis. We then used multilevel modelling to determine whether personality influenced 95% home range size, 50% core area size, movement speed or use of a preferred resource (‘perches’, vision-enhancing prominences such as rocks, which enhance survival) in nature. Data collected over 3 years showed that individual squirrels consistently differed in activity, sociability, boldness and aggressiveness (adjusted repeatability 0.16–0.44) and that activity was correlated with sociability (posterior mean correlation [95% credible interval] = 0.65 [0.39, 0.87]). We did not find an effect of personality on home range size, but bolder individuals maintained larger core areas than shyer individuals. More active and bolder individuals moved faster under natural conditions compared to their less active and shyer conspecifics. Individuals that scored higher for all four personality traits had more perches in both their home ranges and core areas compared to individuals with lower personality scores. Our results are indicative of personality-dependent space use and resource use in this study system. We hope our study will inspire future research that links animal personality with spatial ecology to inform wildlife management in natural ecosystems.

Keywords: animal personalityanimal temperamentbehavioural typeCallospermophilus lateralisground squirrelmovementrepeatabilityresource usesociabilityspace use