Ocean fish are a vital renewable resource for human populations, providing food, employment, and recreation. Many fish stocks worldwide, however, are in a state of serious decline due to overfishing, environmental degradation, climate change, and other stressors. Fishing effort worldwide has remained relatively constant with only slight increases recorded, while the global production of marine fisheries has decreased (Food and Agriculture Organization of the United Nations, 2010). The South Atlantic and Gulf of Mexico regions of the United States have witnessed significant declines in fish stocks that are important to recreational and commercial fisheries. As of 2011, nine fish populations across the two regions were officially classified as "overfished." An additional 12 populations were classified as "subject to overfishing." Biological overfishing occurs when harvest rates from fishing exceed the growth rates of fish stocks. The resulting declines in fish populations can impact the economy at large. This study examines an important component of the costs of overfishing in the South Atlantic and Gulf of Mexico regions -- recreational catch losses from historic overfishing and their associated economic impacts. Our analysis covers nine federally managed overfished stocks in these two regions over the period 2005–2009, the most recent years for which the necessary data were available prior to the 2010 Deepwater Horizon oil spill in the Gulf. Those stocks are black sea bass, red grouper, red porgy, red snapper, and snowy grouper in the South Atlantic; and gag, gray triggerfish, greater amberjack, and red snapper in the Gulf of Mexico. Recreational fishing has long been an important economic activity in these regions. The money spent by recreational fishermen on charter fishing excursions, tackle, bait, fuel, and other expenses supports employment and economic activity across those regions. Our analysis assumes that recreational fisheries could have contributed more to regional economic activity had the stocks been capable of producing greater yields over the study period of 2005–2009. We estimate the size of the recreational catch loss for each species for each year and the economic activity that could have resulted had that catch been available. To arrive at our estimates of recreational catch loss, we compared average annual recreational harvests and effort for each stock for each year over the study period to potential estimated harvests and effort had the stocks been producing at optimum yield. We sourced our measures of optimum yield and maximum sustainable yield for each individual stock from regional stock assessments and fishery management plans. We valued the resulting catch loss by using data on trip expenditures by recreational fishermen in the South Atlantic and Gulf of Mexico. Effort and expenditure data were sourced from the Marine Recreational Fisheries Statistics Survey and includes trips that caught, targeted, or caught and/or targeted the stocks in our analysis.1 Economic multipliers were used to estimate the total direct, indirect, and induced economic activity that could have been generated by those recreational fishing expenditures. Our estimates of catch loss and associated economic impacts are not additive across stocks since trips and their respective expenditures may be associated with multiple stocks. Our analysis finds that recreational fisheries in the South Atlantic and Gulf of Mexico could have contributed millions of dollars more in additional recreational expenditures and associated economic activity had the fish species been producing at optimum yield over the study period. The greatest direct losses were associated with South Atlantic black sea bass and South Atlantic red snapper. Recreational fishermen in the South Atlantic spent $41.7 million on average annually to realize 44% of the total recreational catch that could have been available had the fish population been producing optimally. We estimate that recreational expenditures on South Atlantic black sea bass could have been $52.8 million greater each year over the five-year study period had the stock been producing at optimum yield. An additional $52.8 million in recreational expenditures each year could have generated an additional $138 million in economic output and $40.3 million in income, and supported 896 jobs annually for the region. In the case of South Atlantic red snapper, fishermen spent $9.2 million on average annually over the study period to catch 37% of the recreational catch that could have been available under optimum yield. We estimate that recreational expenditures on South Atlantic red snapper could have been $15.9 million greater each year and could have contributed an additional $41.6 million in economic output and $12.2 million in income, and supported 270 jobs for the region annually between 2005–2009. In the Gulf region, the greatest losses were associated with red snapper, where recreational fishermen spent $22.4 million to realize 64% of the optimal catch that could have been available. We estimate that recreational expenditures on Gulf red snapper could have been $12.7 million greater each year had the stock been producing at optimum yield. An additional $12.7 million in recreational expenditures each year could have generated an additional $33.2 million in economic output and $9.7 million in income, and supported 215 jobs annually for the region. Our findings support the conclusion that overfished stocks can lead to significant economic losses for regional economies through forgone recreational fishing expenditures. This is only one component of the cost of overfishing. Our analysis does not estimate the value of catch losses in commercial fisheries or the broader impacts on ecosystems and biodiversity. The total value of catch losses resulting from historic overfishing would be greater still if other impacts had been considered. Despite these limitations, this study provides strong economic evidence in support of maintaining healthy ocean fish populations and continuing efforts to rebuild stocks currently subject to overfishing or classified as overfished.