Spatial cognitive abilities of a tide-pool fish show resilience to noise pollution

Abstract

Noise pollution may impair the cognitive performances of several animal species, producing suboptimal behavioral responses. Involuntary shifts in attention from noise pollution (an irrelevant stimulus) may account for this outcome, specifically, by reducing the available cognitive processing capacity to conduct relevant tasks; the ‘distracted prey hypothesis’. Many reef fish mediate predation risks by pairing with conspecifics and using refuges; two crucially important resources that are often heterogeneously distributed in space. In a T-maze, we tested the cognitive performances of wild-caught tide-pool fish, Sergeant Major (Abudefduf saxatilis), exposed to control (45 dBA) or noise playbacks (100 dBA). After exposure to a model predator, fish could reach an area containing a refuge and conspecifics (target area), located in one arm of the maze. We posited that fish exposed to noise playbacks would require additional time to reach this target, because of impaired cognitive performances (i.e., learning, remembering). While fish learned to reach the target, no statistical difference existed between acoustic treatments. However, fish exposed to additional noise increased their time spent under shelter and reduced their exploratory behavior. As tide-pools are inherently noisy and structurally complex, residents of these habitats may have cognitive abilities that are resilient to acoustic disturbances.