Modeling effects of toxin exposure in fish on long-term population size, with an application to selenium toxicity in bluegill (Lepomis macrochirus)

► We quantified effect on equilibrium population size as a means of assessing toxicity. ► Simulation model used to assess effects of environmental stochasticity. ► Individual-level effects are typically greater than population-level effects. ► Population-level effects are sensitive to the low-density first-year survival rate. ► Simulations showed extinctions at much lower toxin concentrations than predicted.