The FAO has published the \"Regional Review on Status and Trends in Aquaculture Development in North America,\" which summarizes status and trends of aquaculture development in North America for the period 2010– 2015 and concentrates on activities in Canada and the United States of America.
Differences in coastal habitat (type and extent) and water temperature have produced an aquaculture sector in the United States of America whose species composition is markedly different from Canada’s. A few species (for example trout, Atlantic salmon and oysters) are shared; most are not. Dominance of high-value Atlantic salmon in Canada means that the aquaculture industry is worth more on a per capita basis in Canada, whose population is a tenth of the United States of America’s. More species are cultured in the United States of America, but the contribution from lower value freshwater species is still higher than in Canada. Marine and coastal aquaculture in the United States of America made up only around 50 percent of production in 2014, compared to over 90 percent in Canada. Marine production in 2014 was valued at around US$386 million, and has grown at an annual average of 8 percent between 2009 and 2014, with most gains in marine shellfish. Despite clear potential for significant increases in marine aquaculture production in the United States of America, government policies and public opinion have not been favorable.
The main market for feeds in North America is for finfish. As the largest annual cost associated with culture, feed is a critical area where innovation can bring big dividends. Imports are negligible except for a small amount of specialty feeds imported from Europe. Salmon feeds are manufactured locally or imported; channel catfish feeds are produced in the United States of America.
Reliance on fish meal and fish oil from “forage” fish species such as anchovy is not only vulnerable to declines in meal-fish populations but also viewed as unacceptable. Recent developments have focused on using less fishmeal in feed products, and aquaculture companies are careful to promote advances on this front. The ratio of wild fish input to total farmed fish output fell by more than one-third between 1995 and 2007 (FAO, 2011a).
The “fish in: fish out” ratio varies depending on where the target animal is on the food chain, and its calculation remains a matter of scientific debate. The overall ratio of fish harvested for fish meal and fish oil production to quantities of farm-raised fish and shrimp decreased from 0.7 in 2003 to 0.3 in 2012 (FAO, 2014). Restricting fishmeal and oil to diets used for broodstock, larval and final-stage feeding can reduce the ratio, as can replacement of forage fish sources with trimming wastes, plant or even microbial or algal sources.