It is true that not all aquaculture operations are efficient, environmentally friendly, or sustainable. Just like any industry, there are bad players, and it’s important to know what factors make an aquaculture operation sustainable or not.
The primary concern for the future of aquaculture is what to feed the fish being reared. Exchanging numerous small fish for one larger fish is not an efficient means of producing protein in a world demanding more. This simply shifts the weight of our demand, putting pressure on the wild stocks of small fish as we try to grow the large fish. Luckily, scientific developments are working towards feed recipes that utilize ingredients like algae or methane that would otherwise be considered waste. Recently, researchers at Dartmouth College were able to substitute wild fish oil used in feed with a microalgae that provides equivalent nutritional value. Another possibility is non-animal, non-vegetable pellets created by feeding methane to bacteria. A company in Canada just received national approval to sell insect larvae as a feed ingredient for salmonoids. Fish are now making up a smaller part of most fish meal concoctions, as the importance of smaller fish to the ecosystem is recognized. The true test for these alternative feeds will be that of quantity: can a new source of fishmeal produce enough to keep up with demand from worldwide aquaculture operations. This may in fact be possible for some solutions, while others will have to remain species-specific.
Aquaculture operations are also capable of growing more than carnivorous finfish. As a matter of fact, half of the world’s aquaculture products were realized without feed in 2014 (FAO). Mollusks, as described in our featured article about mussels, are a tasty and profitable seafood that can be grown sustainably in aquaculture due to their filter-feeding nature and minimal space requirements. Oysters, mussels, and clams are some of the most popular. Other farm-raised ocean organisms that do not require fish meal include seaweeds and microalgae. Indonesia is responsible for much of this, and produced 36.9% of the world’s farmed seaweed in 2014 (FAO).
A common argument against aquaculture is its polluting effects on the surrounding environment. While this can be the case in some operations, such as shrimp farming in southeast Asia, it does not mean that every aquaculture facility follows suit. The waste produced from aquaculture depends on the species, the design of a facility, the quality of feed used, and management. Wastewater treatment systems exist to reduce pollution outflow, and the position of an aquaculture site can minimize waste build up. If properly planned, not only can an aquaculture operation reduce the effects of waste, but may even take advantage of those nutrients and recycle the organic matter.
In discussing the environmental concerns it is also important to note the efficiency of aquaculture-raised seafood. Fish have a higher feed conversion ratio, meaning they can convert more nutrients into more protein, and therefore meat, than poultry and other livestock. Because of this, farming fish has a significantly lower carbon footprint than farming chicken, pork, beef, or sheep.
In order to help the consumer determine which seafood products are safe, sustainable, and healthy, numerous organizations have created a variety of certifications. However, this variety can also create confusion. So, which certification is the one you should be looking for? Check out the most common ones below to learn what they mean:
Aquaculture Stewardship Council – a global not for profit founded in 2010 by the WWF and the Dutch Sustainable Trade Initiative that recognizes responsible aquaculture, promotes environmental choice to consumers, and works towards sustainability.
Seafood Watch – Program of the Monterey Bay Aquarium that aims to promote sustainable seafood, that which does not harm sea life or habitat, including both aquaculture and wild caught.
Marine Stewardship Council – Their blue label indicates a fishery that has been certified as sustainable and meets traceability standards. Scientists, the industry, conservationists, and stakeholders are part of the process.
Best Aquaculture Practices – Performs third party audits of aquaculture facilities that assess the entire production chain (farms, processing, hatchery, feed) in order to certify.