Five life-history scenarios were composed to simulate fish population adaptations for survival under various environmental conditions. The scenarios encompassed differences in stage-specific survival, fecundity and hatch success, number of spawning events, and life-span effect response to chronic toxic impacts. The strategies represent a good survivor/generalist (GS), a species exhibiting high young-of-the-year survival, a species exhibiting high adult survival, a species with no parental care or guarding behavior, and an anadromous salmonid strategy. Although the modeled scenarios were similar in population growth rate and imposed toxic effects, differences concerning the influence of various traits were found. Scenarios characterized by a short life span, short time to reproductive maturity, moderate to high survival to reproductive maturity, large number of spawning events, and parental guarding behaviors experienced less perturbation from the imposed chronic stresses. The GS scenario, modeled after the round goby (Neogobius melanostomus), exemplified these characteristics. Scenarios exhibiting little difference between reproductive effort for younger and older adults recovered quickly from stressors on fecundity and adult survival rates. Greater population decline in response to commensurate impacts was seen for life-history strategies with long life span, no parental guarding behaviors, semelparity and annual iteroparity, high adult survival rates, and moderate to low fecundity.