What is aquaculture?

Aquaculture is the controlled process of farming seafood (fish, crustaceans, molluscs, seaweed), especially for human consumption. As the demand for seafood has increased, technology has made it possible to rear common fish species in sea cages in coastal marine waters and in the open ocean.

It is the world’s fastest-growing food production sector which is increasingly dwarfing the traditional fishing industry. It now produces more than $263 billion worth of goods annually, and over half of the seafood we consume today is farmed, which may come as a surprise to many consumers.

Aquaculture in numbers

In 2019, 56% (FAOSTAT 2021) of all seafood consumed worldwide was produced in aquaculture facilities. This is expected to grow even further (up to 32%) as wild-caught fishing plateaus, due to overfishing and biological constraints; the fish cannot reproduce fast enough for their populations to recover, and climate change and human interventions are affecting their environments making it more difficult for them to reproduce.

In aquaculture, fish production is generally measured in tonnes rather than individual fish so estimating the number of fish produced in these facilities can be difficult to calculate due to the diversity of species and harvest weights. However, here are some estimates for three of the key farmed fish species (2018 figures):

Atlantic Salmon - up to 674 million fish produced
Sea Bass - up to 955 million fish
Sea Bream – up to 1,035 million fish

Approximately 109 billion fish are farmed each year, which is more than any other terrestrial farmed animal: chickens 66 billion, pigs 1.5 billion, lamb 588 million and beef is 290 million.

Expansion of aquaculture

The increase in demand for seafood products has not only caused rapid growth in the farming of common fish species (like salmon and seabass) but has also led to the development of farming systems for other aquatic species, such as octopus or tuna. However, different species have different biological and behavioural needs and may not be adapted to live in captivity.