Photo credit: Hongking International Co. Ltd
Experts agree that as wild fish stocks decline and the world's population grows we will increasingly rely on aquaculture to feed the hungry planet. But many conservationists are concerned about the sustainability of an aquaculture industry that uses 58% of the world's fishmeal supply for feed -- mostly from anchovy and sardine fisheries in South America. They are also concerned about the fish in to fish out ratio, which is alarming for species like farmed salmon that require three to four pounds of protein (typically from fishmeal) to produce one pound of flesh. A number of members of the fishmeal industry are looking at developing alternative feedstuffs from vegetable oil and finding new ways to capture fish waste that is currently thrown away. One example is a Norwegian company called EWOS, which has reduced the proportion of marine ingredients in salmon feed from typical levels of more than 75% in the early 1980's to less than 25% today. EWOS recently spoke on a panel at the Seafood Summit in San Diego.
Another interesting example is an open water yellowtail tuna farm near Kona, Hawaii called Kona Blue, which uses "sustainable feed" comprising approximately 30% fish meal and fish oil from Peruvian anchovies and trimmings from fish processed for human consumption, and 70% sustainable agricultural proteins (like chicken trimmings) and oils.
The International Fishmeal and Fish Oil Organization says that the fish in to fish out ratio can be brought down significantly with more sustainable fish feeds, and this will likely become a key issue as the global aquaculture industry grows to supply most of our fish in the future.
More on Fishmeal and Aquaculture:
Thirty Percent Of Global Fish Catch Wasted On Livestock
Future of Food: Fish Farms in Condos
Review: Bottomfeeder: How To Eat Ethically in a World of Vanishing Seafood
CleanFish: Supplying Sustainable Seafood for All