Report for Makiv2

Aquaculture also known as fish farming is one of the fastest growing methods of producing food in the world. The most common type of Aquaculture is done in pens or cages anchored to the ocean floor near the coast. There are also systems of tanks or ponds that operate on land or float on water. While being known for their omega-3 fatty acid benefits, fish do not actually produce omega-3s themselves. Microscopic algae produce them. Herbivorous fish and forage fish obtain omega-3s by eating the microalgae. The larger Carnivorous fish such as salmon or sea bass then eat the forage fish because they need the omega-3s to grow. 30-50 percent of the feed traditionally used for these species consists of ground fish and fish oil. Over 50 percent of the world's fish oil is used in feed for farmed fish.

This is one reason that fish farming is considered unsustainable. In 1977 it took 3 tons of forage fish to produce 1 ton of salmon. A third of global fish harvest goes toward making fish oil and fish meal. As a result, forage fish are being overfished, causing some populations to crash.
Most fish farming methods are harmful to ecosystem as well. Fish waste spill out from nets causing nutrient pollution. Which may lead to oxygen depletion from the water, which stresses or kills aquatic creatures. pesticides and antibiotics can also affect marine life or human health.

How Fish Farming is Becoming More Sustainable

One strategy involves moving aquaculture into the open ocean where the current are strong and steady enough to flush out waste and pests.

Some fish farms are using recirculation systems to recycle their water. The water quality can also be monitored continuously, which lessens the risk of disease and the need for antibiotics.

The rising prices of fish feed and the environmental impacts of over-exploiting forage fish for feed and fish oil have led to an increase in the farming of herbivorous fish and omnivorous fish that require much less fishmeal to produce protein. Meanwhile, research is also ongoing to find alternatives to fishmeal feed or ways to make it more sustainable.

New Kinds of Feed

- Kampachi Farm has experimented with fish diets supplemented with soybeans and plant waste, and replacing fish oil with microalgae and yeast products. In 2013, Kampachi tested three feeds containing no fishmeal at all, and found them all comparable to the standard diet. Researchers at the University of Maryland Center for Environmental Science developed fish feed made completely with corn, wheat and soy. The fish oil was replaced by fatty acids from algae, amino acids and soybean or canola oil. PCB and mercury levels in the fish were 100 times less than those in fish eating fishmeal feed. This is because fishmeal and fish oil in feed can transfer environmental pollutants to farmed fish, while feed made of ingredients from vegetation can reduce them.

- British scientists genetically modified camelina sativa, a plant known for its seed oil, with synthesized genes from algae, enabling the plant to produce omega-3s that successfully replaced fish oil in fish feed; the salmon thrived.

- A Texas A&M University scientist is using distillers’ dried grains with solubles, nutrient-rich grains made in ethanol production, as a cheap source of protein in shrimp feed. He has successfully substituted sorghum and corn distillers’ dried grains for 10 percent of the protein in shrimp feed.

-Calysta, a California based company, is developing protein for feed using bacteria that are fermented and fed methane gas, in a process similar to making beer or bread. The product, called FeedKind, is a natural high-quality protein fishmeal replacement.

-Researchers from Wageningen University in the Netherlands are experimenting with insects as a new source of omega-3 fatty acids. The scientists extracted the naturally produced oil from a variety of insects and are researching the breeding, optimal diet and processing of the insects for oil. A 2014 FAO paper concluded that insect meal could replace between 25 and 100 percent of soymeal or fishmeal in fish diets with no adverse effects.

In 2010, only 36 percent of fishmeal came from the trimmings and waste (heads and innards) of fish fillets, which are usually discarded. China increasingly relies on wild-caught fish for fishmeal and fish oil. A Stanford University study found that using the waste from seafood processing plants, and adding algae or ethanol yeast to boost the protein content could replace half to two-thirds of the current fishmeal used in Chinese aquaculture.

How Do We Make Sure Aquaculture is Sustainable?

Because there are a number of different international and national certification schemes for aquaculture, the FAO developed technical guidelines for aquaculture certification and an evaluation framework. But while environmental impact assessments and certification are required for many large fish farms, they are not required for small farms, many of which are unsustainable. Regulations governing responsible aquaculture development in many countries are weak.

In a sign of the ongoing growth of fish farming, NOAA Fisheries recently published a new rule, opening up federal waters from three to 200 miles offshore in the Gulf of Mexico to aquaculture.