Data from: Active crocodiles are less sociable

How animals move and associate with conspecifics is rarely random, with a
population’s spatial structure forming the foundation on which the social
behaviours of individuals form. Studies examining the spatial–social
interface typically measure averaged behavioural differences between
individuals; however, this neglects the inherent variation present within
individuals and how it may impact the spatial-social interface. Here, we
investigated differences in among-individual (co) variance in sociability,
activity, and site fidelity in a population of wild estuarine crocodiles,
Crocodylus porosus, across a 10-year period. By monitoring 118 crocodiles
using coded acoustic transmitters and an array of fixed underwater
receivers, we discovered that not only did individual crocodiles
repeatably differed (among-individual variation) in each behaviour
measured, but also in how consistently they expressed these behaviours
through time (within-individual variation). As expected, crocodile
activity and sociability formed a behavioural syndrome, with more active
individuals being less sociable. Interestingly, we also found that
individuals that were either more sociable or displayed greater site
fidelity were also more specialised (lower within individual variation) in
these behaviours. Together, our results provide important empirical
evidence for the interplay between spatial, temporal and social
individual-level behavioural variation and how these contribute to forming
behavioural niches.