Assessment and prediction of the impact of pollution on animal populations are required to improve waste management strategies. This information is not easy to obtain in the marine environment because of the large natural fluctuations in abundance of organisms. Use of information on commercial fishery populations in impact assessment is advised for three reasons: (1) pollution-related effects on marine fishery populations will have direct economic consequences, (2) many major fish stocks that already are overfished should be more vulnerable to additional stresses than nonexploited populations, and (3) long-term data bases that reflect population changes are available.

The Atlantic menhaden, Brevoortia tyrannus, an economically and ecologically important fish, inhabits coastal and estuarine waters along the mid-Atlantic coast of the United States. Within its range, we have identified a number of man-related activities that could potentially affect its population size. Adverse impacts in coastal waters could result from an increase in the ocean dumping of sewage sludge and industrial wastes and oil spilled during the development of offshore oil reserves. In estuaries, adverse impacts could result from a slow but steady decline in water quality associated with human population growth and industrialization of coastal areas.

Scenarios were developed using a density-independent Leslie matrix model and data from the Atlantic menhaden fishery to simulate population responses to both catastrophic and chronic mortalities. These simulations demonstrate that a fish population which is heavily fished may have limited compensatory reserve and thus may be particularly sensitive to pollution.

Improvement in our capacity to predict the effects of pollution on fisheries requires an understanding of the environmental factors that control variability in fish populations and the effect of multiple stresses on these stocks over their entire geographical range. Increased predictive capability can be gained most cost-effectively through closer integration of the disciplines of population dynamics and toxicology.