We have been farming fish and shellfish as a means of sustenance for thousands of years. Yet today’s technologically advanced aquaculture sector, which includes the culture of more than 500 different aquatic animals, is a world away from our earliest beginnings, which were predominantly based on the capture and ranching of wild species.
According to the latest figures from the Food and Agriculture Organization of the United Nations (FAO), total world aquaculture production is in excess of 101 million tonnes with a value exceeding US$165 million. In 2014 a significant milestone was reached, when aquaculture’s contribution to the global seafood supply for human consumption overtook that of wild-caught fish. Aquaculture has, in fact, become the fastest growing food supply sector in the world today.
NEED TO FEED
The reason for the tremendous growth of aquaculture lies in the growing global demand for healthy and delicious seafood products, paired with wild-capture fisheries’ inability to sustainably increase their current yield. And with more than 9 billion people expected to be walking the Earth by 2050, up from the present population of 7.5 billion, aquaculture will be increasingly called upon to bridge the gap between the supply and needs of consumers. In fact, it has been estimated that farmed production will need to double in order to meet the mid-century demand for seafood.
In general, the fish farming sector is well aware of both the challenges and the opportunities brought by these circumstances. Many of the industry’s leading thinkers are already working hard to improve the sector’s performance – making it more responsible, sustainable and innovative, at the same time as providing larger volumes of healthy and delicious protein for us to eat.
It’s fair to say that aquaculture is far different today than it was just 30 or so years ago. It has become a net producer of protein – using about half a tonne of whole wild fish to produce one tonne of farmed seafood. In actual fact, when it comes to livestock production, farmed fish is now the most resource-efficient animal protein available to humans, while salmon has the most efficient feed conversion ratio of all proteins and a carbon footprint that is about one-tenth that of beef. And crucially, the harvested edible yield is higher than all other centre-plate proteins.
Not only has aquaculture embraced technological innovation, but far stricter rules are in now place and the environmental monitoring procedures are much more robust. Indeed, while fish farming of old relied on wild fish, most of today’s aquaculture systems have little or nothing to do with ocean stocks. Predominantly, cultured species are grown from eggs in hatcheries, and then transferred to bigger pens, ponds or tanks, for further growth until they reach the size for harvest.
MODERN DAY FARMING
Different fish are cultured in different ways depending on their needs and the region that they are grown in. Once they’ve reached a certain size, most salmon are grown to harvest size in floating pens or cages in open water that allow seawater to flow through to maintain water quality within the cage, for example. Warmwater shrimp, meanwhile, are mostly raised in brackish water ponds that are not open to any water bodies.
But no matter the species that’s being produced, by far the most expensive cost for farmers is feed. Different species require different diets and these – most commonly provided in the form of dried pellets – are specifically formulated to contain all of the essential nutrients that they need to keep them healthy and growing, and to maintain the human health benefits of seafood consumption. Almost all of these ingredients are from natural sources, with just a small percentage coming from nature-identical products.
As the global population continues to increase, so too will the demand for more protein. It is abundantly clear that to meet our planet’s growing needs, we must establish and maintain protein sustainability. There is no doubt, therefore, that aquaculture will play an ever-increasingly important role in addressing the global food security challenge, as well as making a greater contribution to balanced diets and healthy lifestyles.