Seafood is a growing part of the economy, but its economic value is diminished by marine diseases. Infectious diseases are common in the ocean, and here we tabulate 67 examples that can reduce commercial species' growth and survivorship or decrease seafood quality. These impacts seem most problematic in the stressful and crowded conditions of aquaculture, which increasingly dominates seafood production as wild fishery production plateaus. For instance, marine diseases of farmed oysters, shrimp, abalone, and various fishes, particularly Atlantic salmon, cost billions of dollars each year. In comparison, it is often difficult to accurately estimate disease impacts on wild populations, especially those of pelagic and subtidal species. Farmed species often receive infectious diseases from wild species and can, in turn, export infectious agents to wild species. However, the impact of disease export on wild fisheries is controversial because there are few quantitative data demonstrating that wild species near farms suffer more from infectious diseases than those in other areas. The movement of exotic infectious agents to new areas continues to be the greatest concern.

Efforts to restore the native oyster in the Chesapeake Bay enjoy enormous public support and have consumed and continue to consume vast, some would argue unreasonable and unjustifiable, amounts of funding. Despite this support the stated goals of restoration efforts are poorly defined and consequently provide no realistic measures of success in terms of time, space, or biomass. Quantitative approaches used successfully in management of and rebuilding plans for other marine and estuarine species have not been appropriately applied. Basic information in oyster population dynamics and ecology has been inadequately appreciated in defining the quantitative problem. Given these limitations it is not surprising that little success has been achieved despite the massive investment. We note a lack of ability to predict recruitment, and limit the ingress and impact of disease. Without control of both of these functions, populations cannot be managed in a self-sustaining rebuilding mode within the footprint that they either currently occupy or formerly occupied. Sustained expansion of that footprint through substrate provision is prohibitively expensive, beyond the limits set by availability of substrate material, and futile in the presence of disease and susceptible oysters. Without attaining a substantially increased and rebuilding population, ecological services will be limited. Water quality impacts will, in reality, be modest, local and seasonal, and still subject to being overwhelmed by periodic storm events. Coherent and rational evaluation of biological limitations will lead to more realistic, and indeed very modest goals for ecological restoration. We must accept the fact that efforts to date to restore native oyster populations have failed and the prognosis for improvement of this situation is continued failure. The argument is proffered that stabilizing the present bed footprint with a realistic and sustainable population and the promotion of aquaculture to increase commercial yield is a more predictable and stable economic investment. Each of these options is consistent with the most realistic ecological outcome and should take priority in future efforts.