The tools for effective management of wild fisheries are well established (Beddington et al., 2007; Hilborn, 2007), and there are encouraging examples of success (Safina et al., 2005). Nevertheless, the required actions have rarely been implemented (Rosenberg et al., 2006). In contrast, subsistence overfishing in developing nations is commonly a matter of survival, so that alternative sources of protein and livelihood are required to bring the situation under control (McClanahan et al., 2006; Hilborn, 2007). More fundamentally, however, wild fisheries cannot possibly sustain increasing global demand regardless of how well they are managed. Industrial scale aquaculture of species low on the food chain is the only viable alternative. But this in turn will require strong new regulation to prevent harmful ecosystem consequences such as the destruction of mangroves for shrimp farms and the impacts on wild salmon populations caused by the explosion of parasitic copepods that infect salmon farms in British Columbia (Goldberg and Naylor, 2005; Krkosek et al., 2007). Despite all of these concerns, however, the only thing standing in the way of sustainable fisheries and aquaculture is the lack of political will and the greed of special interests. Simply enforcing the standards of the Magnuson–Stevens Act and the U.S. National Marine Fisheries Service would result in major improvements in United States waters within a decade (Safina et al., 2005; Rosenberg et al., 2006).
Heavily subsidized overuse of chemical fertilizers and pesticides, poor soil management practices, and unregulated animal production systems are the major sources of excess nitrogen and other nutrients in the environment that fuel coastal eutrophication (Jackson et al., 2001; Rabalais et al., 2007; Turner et al., 2008) and severely degrade terrestrial ecosystems (Tilman et al., 2002; Clay, 2004; Galloway et al., 2004; Dale and Polasky, 2007). Manufacture of chemical fertilizers also consumes huge amounts of energy from natural gas (Howarth, 2004). Removal of subsidies and taxation of fertilizers would significantly reduce nutrient loading, eutrophication, and emissions of greenhouse gases with only modest decreases in food production and increased costs.
The rise in greenhouse gases and the resulting global economic, social, and environmental consequences comprise the greatest challenge to humanity today. Moderation of consumption of fossil fuels in a time of rising global aspirations and finding alternative sources of energy will