Effects of Pollution on Fish Behavior, Personality, and Cognition: Some Research Perspectives

Lisa Jacquin,Quentin Petitjean,Pascal Laffaille,Jessica Côte,Séverine Jean

doi:10.3389/fevo.2020.00086

Abstract

Pollutants, and more generally, environmental stressors, are a neglected source of behavioral and cognitive variations in wild populations. Based on recent literature in fish, we highlight four interesting research perspectives to better understand the effects of pollutants on the links between behavior, cognition and fitness. First, (1) we review the neurotoxic effects of pollutants on fish behavior, personality and cognition. These effects could in turn affect the level of exposure to pollutants, potentially generating feedback loops that may amplify the effects of pollutants on fitness. Second, we propose that (2) the effects of pollutants should be studied in a multistress context, i.e. in realistic environmental conditions in combination with other stressors, because some stressors could amplify the behavioral effects of pollutants on fitness. Third (3), existing studies show that physiological and behavioral traits are often linked in syndromes. Pollutants could lead to syndrome disruption, which could affect the evolutionary trajectories of exposed populations. Future studies should thus focus on the complex links between traits to better understand the consequences of stressors on evolutionary trajectories. Fourth, (4) exposure to chronic pollution could lead to local (mal)adaptation, which could result into high intraspecific variability of sensitivity among populations. In addition, evolutionary responses to pollution could constrain, or be constrained by evolutionary responses to other stressors. We thus encourage future studies to use integrative approaches to bridge the gap between ecotoxicology, cognitive ecology and evolutionary ecology in a multistress framework to improve our ability to predict the effects of anthropogenic stressors on wildlife.

Highlights

Human activities are the sources of many organic and inorganic contaminants such as plastics, pharmaceuticals, pesticides, and metals that have alarming impacts on terrestrial and aquatic ecosystems (Scott and Sloman, 2004; Zala and Penn, 2004; Saaristo et al, 2018)
Direct effects of pollutants on animal physiology and mortality have been included as part of routine ecotoxicology studies (Butcher et al, 2006; Ashauer et al, 2013), but more complex behavioral
We review the existing literature focusing on fish to investigate the behavioral effects of pollutants in a multistress perspective

Summary

INTRODUCTION

Human activities are the sources of many organic and inorganic contaminants such as plastics, pharmaceuticals, pesticides, and metals that have alarming impacts on terrestrial and aquatic ecosystems (Scott and Sloman, 2004; Zala and Penn, 2004; Saaristo et al, 2018). The links between behavioral changes, cognitive performances, and individual fitness are rarely taken into account when studying contaminant effects, which limits our ability to predict the cascading long-term impacts of human activities on population persistence and evolutionary trajectories. Three-spined stickleback Gasterosteus aculeatus exposed to a polymetallic stress were more susceptible to an immune challenge through changes in oxidative responses (Le Guernic et al, 2016) Parasites and their associated immune challenges could act as important biotic constraints altering the effects of pollution on fish behavior and fitness, but few studies experimentally tested this hypothesis, especially in fish. Syndromes resulting from physiological trade-offs resulting from resource allocation could potentially change across environments, so that different trait combinations could be found in natural populations depending on levels of pollution, resource availability and/or other stressors (Bell and Aubin-Horth, 2010; Killen et al, 2013). Pollution-induced behavioral changes could potentially generate maladaptive effects and generate evolutionary traps (Sih et al, 2011; Brady et al, 2019), but this hypothesis remains to be tested

CONCLUSION

DATA AVAILABILITY STATEMENT