Of the 145 million metric tons of fish harvested annually worldwide, nearly 80 million metric tons come from the oceans. Today, marine fish populations are in serious trouble due to overfishing, ecosystem degradation, and inept fisheries management. Unless significant changes are made to how we harvest and consume seafood, many popular fish species could be commercially extinct by mid-century (FAO, 2010).
According to leading marine fisheries researchers, upward of 85 percent of the world’s wild fisheries either are being fished at the maximum rate that would allow for replenishment, or are already overexploited, depleted, or recovering from depletion (FAO, 2010).
The FAO suggests that “peak fish”—the maximum wild capture fisheries potential from the world’s oceans—was reached in 1996. In short, there are too many boats on the water and too many people going after the same fish. Some estimates place the worldwide fishing fleet at 200-300 percent of current ocean capacity. This overcapacity is difficult to resolve simply, as removing subsidies and revoking fishing rights can result in vast numbers of unemployed fishers with little ability (or local economic opportunities) to switch careers (World Bank, 2008).
Loss of Biodiversity
Overfishing, destructive fishing methods, coastal development, climate change (ocean warming and acidification), and pollution from agricultural and industrial run-off can severely impact ocean habitats and biodiversity. More than 100 species of fish are currently listed as threatened species. Ecosystems with higher naturally occurring biodiversity (i.e., species richness) are more stable and are less likely to experience collapses of commercially important fisheries (UNEP, 2010 [pdf]).
Non-selective fishing gear, like trawlers, gillnets, and some longlines, can result in huge amounts of bycatch—the harvest of untargeted species, including birds, dolphins, sea turtles, and other edible fish. Depending on how and where it is caught, harvesting one pound of shrimp, for example, can result in as much as 62 pounds of non-shrimp bycatch. Estimates of annual bycatch worldwide vary depending on the methodology, but are between 7 million and 38 million metric tons. Not only is this collateral damage a further threat to already vulnerable wild fish populations, but nearly all bycatch goes to waste (Marine Policy, 2009; FAO, 2005).
Illegal, unreported, and unregulated (IUU) fishing is a significant environmental and economic problem. Especially on the high seas and in the developing world where regulation and enforcement are non-existent or where fisheries governance is weak and underfunded, IUU fishing threatens both the sustainable management of marine resources and the livelihoods of local fishing households. The true costs of these illicit practices are unknowable, but estimates are that between $10 billion and $24 billion worth of IUU fish are caught worldwide per year (FAO, 2010).