Fig. 5

Diel changes in average displacement from the central place by blacktip reef (a, n = 20) and grey reef sharks (c, n = 20). Grey and light green backgrounds show night and day respectively. Probabilities of sharks being in state 2 (high activity) are shown as dark green lines (redrawn from Fig. 2). There were diel differences in number of detections (b, d) so daytime estimates of distance are based on larger sample sizes. Blacktip reef shark nocturnal displacements averaged 1 km, while grey reef sharks averaged 3 km from the central place