Feeding a Hungry World
With the largest coastline on earth and more lakes than the rest of the world combined, it comes as little surprise that fisheries form a large part of Canada’s heritage and natural resource economy. School children are taught the lore of the Portuguese fisherman centuries ago who could dip a basket into the waters off our Atlantic coast and lift it out, full of cod; however, the harrowing reality for thousands of Newfoundlanders in the 1990’s when the cod fisheries collapsed serves as a sharp reminder that sustainable stewardship of our plentiful resources is paramount. Like farming, fisheries have faced rapid change in technologies and policies, propelling the industry into a future fraught with questions of how to feed an exponentially growing human population while safely stewarding a sensitive natural resource.
Leading this charge into the future of fisheries is the practice of fish farming, also known as aquaculture. While providing a source of fish that does not devastate wild fish populations, aquaculture raises its own issues of ethics and cleanliness, making it a divisive topic in public and policy spheres alike. Some farmed fish are kept at high densities and in close proximity to one another making disease transmission easier, and their waste and uneaten food can be sources of contamination to coastal waters surrounding the fish farms.
Bryan Neff and his lab group in the Biology Department at Western University are researching best practices for ethical and sustainable aquaculture by using advanced genetic techniques and collaborating with Canada’s Department of Fisheries and Oceans as well as aquaculture companies.
“We use genetic tools to identify the salmon with the best traits for breeding, much like is done with horses or dogs,” says Bryan Neff. They sequence salmon genes to find individuals with naturally high levels of immunity and growth rates, and then breed those individuals for production.
Farmers can reduce their reliance on antibiotics when fish populations have naturally high immunity, and fish with high growth rates use food efficiently to produce larger quantities of meat for the market. Farmed salmon are fed a diet of fish meal which is made from smaller fish, such as anchovies. These smaller fish are harvested around the world, often off the coasts of countries dumping chemicals in their waters and can be a source of toxins to fish in aquaculture communities. To make matters worse, these feed fish are being harvested to extinction, raising the issue of sustainability in salmon farming. Alongside genetic research, the Neff lab is researching sustainable diets for aquaculture with the goal of replacing fish meal while maintaining high levels of omega fatty acids in the farmed salmons’ diets, benefiting consumers and ultimately the health of our oceans.
Feeding farmed fish represents the largest single cost in aquaculture (up to 50-70% of total costs); Neff’s research into breeding fish with greater growth efficiency reduces feeding costs by up to 25% — on the global scale that would equate to around $25 billion saved annually. Currently, about half of the fish consumed by humans comes from aquaculture and the industry is growing at a greater rate than the
human population. Globally, fish forms a significant (20% or more) part of the diet of over three billion people. Cost savings across the industry, even small percentages, will have massive implications for the ecological sustainability and food security for people around the world, as demand on natural resources, alongside the human population, grows exponentially.