Resumen de Fish personality, fisheries, invasive species and the risk of collapse in coastal socialecological systems
Intra-specific variability in fish behaviour (fish personality) has emerged as a key player in many ecological and evolutionary processes. We studied here how fish personality may shape the resilience and the dynamics of a whole social-ecological system; the pearly razorfish (Xyrichthys novacula) fishery. Using underwater-video we first documented an exceptionally high exploitation rate. Using a theoretical approach and acoustic tracking, we subsequently found that individuals showed repeatable behaviours suggesting the presence of fish personality. We examined the survival of the tagged fishes and found that harvesting induced strongly negative selection gradients on fish personality. The exploited population of pearly razorfish was characterized by timid individuals showing only localized and low-intensity movement patterns (timidity syndrome). While we found the timidity syndrome is able to maintain the population of the pearly razorfish stable across years, it may have strong effects on the profitability of the fisheries and stock assessment. In fact, we show how the system is more close to a social collapse, rather than to an ecological collapse, and we demonstrate fish personality is playing a major role on this fact. The behaviourallymediated equilibrium in the social-ecological system studied here has been recently truncated by the invasion of the tropical macroalgae.
