Aquaculture is the fastest growing sector of the world food economy, increasing by more than 10% per year and currently accounts for more than 30% of all fish consumed. While most farmed fish are vegetarian species, such as carp and catfish, farming of carnivorous species, such as salmon, is a booming industry and the number of other farmed carnivorous species is growing rapidly. However, industrialized farming of carnivorous fish such as salmon requires the intensive use of resources and exports problems to the surrounding environment. Detrimental effects include: displacement of wild fish populations; harmful genetic interactions with wild fish; transfer of parasites and disease; discharge of untreated wastes into coastal waters; use of chemicals and antibiotics; and the use of large amounts of wild fish for feed.
The increasing amount of the global commercial catch of small fish, such as anchovies and sardines, going to produce fish feed for farming of carnivorous fish species is becoming a serious sustainability issue. "Many people expect that aquaculture will relieve pressure on ocean fish populations, most of which are now already fished beyond capacity," stated Michael Weber, the report's author. "But it takes approximately three pounds of wild caught fish to produce just one pound of carnivorous fish. Clearly, this is not the way for aquaculture to feed the world."