One Fish, Two Fish, Lots of Fish Come from Aquaculture
Americans annually consume an average of 20.5 pounds of seafood. Fish, both shellfish and finfish, is a good source of protein and fatty fish contains omega-3 fatty acids, making them a part of a healthy diet. Although overfishing remains a risk to sustain this consumption, the growth of aquaculture is helping ensure continued access to seafood without endangering fish populations.
Aquaculture is the breeding, raising, and harvesting of aquatic organisms, including shellfish, seaweed, and finfish. Originally developed in China more than 4,000 years ago, aquaculture, also called aquafarming, has gradually expanded across the globe. Today, it’s the fastest-growing global industry for producing protein. Fifty percent of the world’s seafood comes from aquaculture.
Types of Aquaculture
The three main “crops” of aquafarming are algae, in the form of seaweed and kelp; shellfish, such as oysters, mussels, and clams; and finfish—what we usually think of when we say fish—such as salmon, tuna, catfish, and cod.
Algae: Seaweed and kelp are types of algae that can be cultivated as food sources. According to "What Is Aquaculture" in National Geographic, growing seaweed is not only simple, but it can also be beneficial to the environment. According to Anoushka Concepcion, an assistant extension educator in marine aquaculture at the University of Connecticut, “Seaweed farming, and all marine aquaculture, produces far less carbon emissions when compared to terrestrial farming and livestock production.” Seaweed and kelp are easy to grow because they don’t need much attention once they’re seeded on longlines, horizontal ropes strung underwater. They are fast-growing crops with a two-month harvest window.
Shellfish: Oysters, mussels, and clams are also uncomplicated to farm. Mussel and oyster larvae are placed on longlines and in baskets that are placed in water to grow to full size before harvest, usually about one to two years. Clams are bottom-cultured, burrowing into the ocean floor. These shellfish get what they need from the ocean. In addition, oysters and mussels are beneficial to ocean health. They can filter up to 50 gallons of water a day, which lowers nitrogen levels.
Finfish: Fish like tilapia, salmon, and catfish are more complicated to farm because farmers need to manage ever-changing environments to raise healthy fish. Finfish are started in hatcheries and moved to aquaculture farms when they are fingerlings, about a year old. These farms vary from onshore earthen ponds to floating offshore coastal farms: The fish are raised in the type of water best for their breed, be it warm, cold, fresh, or salt.
The Benefits of Aquaculture
As noted earlier, aquaculture is a low-carbon-emissions enterprise, especially compared to traditional farming and livestock production. As an industry, aquaculture benefits local economies by providing jobs and healthy, accessible food. Shellfish aquaculture can help clean algae blooms and filter waste out of the water. Fish farming produces high-quality, heart-healthy protein, which the Mayo Clinic says helps reduce the risk of heart disease in "Omega-3 in fish: How eating fish helps your heart." All-in-all, the pros of aquaculture far outweigh any disadvantages.
Discussion Questions
- Why is aquaculture of finfish more complex than other types of aquaculture?
- How is aquaculture beneficial to the environment?