The most farmed fish in the world are carp, tilapia, catfish, and salmon, but aquaculture extends well beyond finfish to include shrimp, oysters, clams, mussels, and seaweed. Global aquaculture produced over 126 million tonnes in 2021, with carp alone accounting for nearly a quarter of all production.
Carp: The World’s Most Farmed Fish
Carp and related species dominate global aquaculture with 31.1 million tonnes produced in 2021, representing about 25% of all farmed aquatic species. The group includes grass carp, silver carp, common carp, bighead carp, catla, and rohu. Carp farming has deep roots, with recorded practices going back 2,500 years, and the industry has grown at an average of 6% per year over the past three decades.
Production is overwhelmingly concentrated in Asia. China alone produces about 65% of the world’s farmed carp, with India contributing another 19%. These fish thrive in freshwater ponds and are highly tolerant of a wide range of temperatures and environmental conditions. Most carp species can feed partly on natural food sources in their environment, which keeps feed costs low and gives carp farming a relatively small carbon footprint compared to other types of aquaculture.
Tilapia
Tilapia is the second most important group of farmed fish by volume, with global production reaching about 6.3 million tonnes in 2021. Nile tilapia is the dominant species, though blue tilapia, Mozambique tilapia, and various hybrids are also widely farmed. Production grew at an average rate of about 10% per year between 1999 and 2018, making it one of the fastest-expanding sectors in aquaculture.
Tilapia are warm-water freshwater fish that grow quickly and tolerate crowded conditions, which makes them well suited to pond farming in tropical and subtropical countries. Indonesia has been a major driver of recent growth, adding over 100,000 tonnes in a single recent year. You’ll find farmed tilapia in grocery stores worldwide, typically sold as mild, white-fleshed fillets at a lower price point than salmon or shrimp.
Catfish
Farmed catfish produced 6.1 million tonnes globally in 2021, making them the third largest group of farmed finfish. The major producing countries are Indonesia, China, India, Nigeria, and Vietnam, though production trends vary by country. Vietnam and Bangladesh have seen recent declines, while Indonesia and China continue to expand.
Catfish are bottom-feeding freshwater fish that adapt well to warm, low-oxygen water, which makes them practical to raise in earthen ponds. In the United States, channel catfish is the primary farmed species, concentrated in the Mississippi Delta region. In Southeast Asia, pangasius (sometimes labeled “swai” or “basa” at the supermarket) is the dominant farmed catfish and one of the world’s most affordable farmed fish.
Salmon and Trout
Salmon, trout, and related species produced 4.2 million tonnes in 2021. Atlantic salmon is the star of this group and one of the highest-value farmed fish in the world. Norway is the largest producer, followed by Chile, the United Kingdom, and Turkey.
Farming Atlantic salmon is more complex than raising warm-water species because salmon are anadromous, meaning they naturally move between freshwater and saltwater during their lives. Farms replicate this cycle in two stages. Eggs are fertilized and raised in on-land freshwater hatcheries for about a year. During that time, the young fish undergo a transformation called smoltification that prepares their bodies for saltwater. They’re then transported to large net pens anchored in coastal waters, where they feed and grow for roughly two more years before harvest.
Farmed Atlantic salmon contains slightly more omega-3 fatty acids than wild salmon, largely because farmed fish carry more fat overall. A 100-gram serving of farmed salmon provides about 500 mg of EPA and 900 mg of DHA (the two omega-3s linked to heart and brain health), compared to about 400 mg and 800 mg respectively in wild salmon. Rainbow trout is also widely farmed, primarily in freshwater raceways and ponds.
Shrimp and Prawns
Marine shrimp and prawns are the fourth largest aquaculture group overall, with 7.3 million tonnes produced in 2021. Farmed shrimp now make up 55% of all shrimp produced globally. Two species dominate: Pacific whiteleg shrimp and giant tiger prawns, which together account for about 80% of farmed shrimp production.
The five largest shrimp farming countries are China, India, Vietnam, Indonesia, and Ecuador, and all five have been expanding production. Pacific whiteleg shrimp are typically harvested within a few months of stocking, while giant tiger prawns are usually harvested within a year. Most shrimp farms use coastal ponds filled with brackish or saltwater, though practices range from low-density traditional ponds to high-intensity operations with aeration and water treatment systems.
Oysters, Clams, and Mussels
Shellfish farming is a massive part of global aquaculture. Oysters produced 6.7 million tonnes in 2021, and clams, cockles, and arkshells added another 5.8 million tonnes. China dominates both categories, accounting for 87% of global oyster farming and 95% of global clam farming.
Bivalve shellfish are filter feeders, meaning they pull nutrients directly from the surrounding water rather than requiring manufactured feed. This makes them one of the most environmentally efficient forms of aquaculture. Common farmed species include the Pacific oyster (the most widely produced oyster worldwide), the Eastern oyster (common in North American farming), and the Northern quahog (hard clam). Mussels are farmed extensively in Europe, China, and Chile, typically grown on ropes or poles suspended in coastal waters.
Sea Bass and Sea Bream
European sea bass and gilthead sea bream are the two species that defined the growth of marine aquaculture in the Mediterranean over the past few decades. Greece and Turkey are the largest producers, followed by Spain, Italy, and Egypt. These fish are raised in offshore net pens or, less commonly, in land-based tanks, and they command a premium price in European markets.
Both species require saltwater throughout their lives, which means farming happens exclusively in coastal or offshore environments. Production volumes are modest compared to carp or tilapia, but sea bass and sea bream are among the most recognizable farmed fish in European restaurants and supermarkets.
Emerging Species
Several newer species are gaining traction in aquaculture. Cobia is considered one of the most promising candidates for warm-water marine fish farming. Cage aquaculture for cobia started in Taiwan in the early 1990s and has since expanded across Asia, including Vietnam, China, and the Philippines. In the Caribbean, trials have shown cobia can grow to about 6 kilograms in a year in submerged ocean cages. Production is also being explored in land-based recirculating systems.
Barramundi is farmed in Australia, Southeast Asia, and increasingly in recirculating indoor tanks in the United States and Europe. Yellowtail species, including amberjack and California yellowtail, are being raised in net pens and evaluated for offshore farming. Red drum (also called redfish) and striped bass are farmed in smaller volumes, primarily in the United States. All of these species are positioned as higher-value alternatives to the established farmed fish, targeting consumers looking for variety beyond salmon and tilapia.
Seaweed
Though not fish, seaweed is worth mentioning because it represents a huge share of what aquaculture farms actually produce. Brown seaweeds (17.6 million tonnes in 2021) and red seaweeds (17.5 million tonnes) together accounted for nearly 28% of all global aquaculture production. China is the largest producer of brown seaweed, particularly Japanese kelp, while Indonesia and the Philippines lead in red seaweed farming. Farmed seaweed is used in food products, cosmetics, animal feed, and as a source of thickening agents in processed foods.