Near but not neighbours: juvenile white sharks move together but stay apart

Context White sharks (Carcharodon carcharias) have traditionally been viewed as solitary apex predators. However, recent research suggests that they exhibit more nuanced social behaviors, including non-random co-occurrence (spatial associations) and potential social structuring, across ontogenetic stages. Aim This study aimed to investigate the movement behaviors and spatial dynamics of juvenile white sharks (JWS) at an aggregation hotspot in Southern California, to examine whether their co-occurrence is socially or environmentally driven. Methods Using high-resolution acoustic telemetry data from 20 tagged juvenile white sharks, we analyzed their movements to assess home-range overlap, proximity, encounter rates, and movement correlation patterns. Correlated movement was evaluated using drift and diffusive correlation metrics. Additionally, generalized linear mixed models were applied to identify environmental variables influencing correlated movement. Key results Juvenile white sharks exhibited extensive home-range overlap, frequently (simultaneously) occupying the monitored habitat, and generally maintained closer proximities to each other than would be expected from random movement. However, despite this shared space use, direct shark–shark encounters were infrequent. Drift correlation was detected among all individual pairs, whereas only 66% of pairs showed diffusive (turning/following component) correlation, indicating limited direct following behavior. Factors such as separation distance, diel period, lunar phase, tide height, and chlorophyll-a concentrations significantly influenced movement correlation. Conclusion Juvenile white sharks at aggregation sites demonstrate non-independent movement patterns, but these behaviors are predominantly shaped by environmental conditions rather a need for direct social interactions. This suggests that aggregations may arise from a collective response to favorable environmental features rather than from social cohesion, highlighting the importance of habitat characteristics in driving the spatial ecology of this species. Implications From a management perspective, our results suggest white shark occurrence and short term clustering within nursery habitat may be more reliably predicted from abiotic contexts than from social attraction. Thus, management decisions regarding monitoring design, adaptive beach safety considerations and information communication may be best informed through habitat and habitat-condition based modeling andforecasting of residency and movement likelihoods, especially during periods where combinations of biotic and abiotic cues are associated with stronger shared directional movement.