Analogous to other top predators foraging on patchy resources, the spatial behaviour of fishers provides information on the spatial organization of fish. Focusing on the Peruvian anchovy purse-seine fishery, vessel monitoring system data are used to describe fishing vessels' trajectories, and acoustic survey data to characterize anchovy spatial distribution. Vessel trajectories were analysed in terms of move-length distribution, whereas fish distribution was characterized by spatial extent, concentration, and fractal dimension. Fishers perform Lévy flights that can be characterized by a single statistic (μ); μ is significantly correlated with the fractal dimension of fish distribution. It is argued that the Lévy statistic is a good candidate for an ecosystem indicator that might contribute to real-time monitoring of ecosystems.