Aquaculture is defined as the farming of aquatic organisms, including the cultivation of fish, mollusks, crustaceans, and aquatic plants. This method has grown rapidly to meet global demand, providing a substantial portion of the world’s seafood supply. For the first time in history, farmed seafood production has surpassed that sourced from wild capture fishing. Aquaculture now contributes a record 57% of all aquatic animal products destined for direct human consumption globally.
The Global Production Ratio
The rapid expansion of farming aquatic animals marks a significant shift in how the world obtains seafood protein. Data from 2022 showed that global aquatic animal production, including both wild-caught and farmed species, reached a record 185.4 million tonnes. Aquaculture produced 94.4 million tonnes of aquatic animals, officially surpassing the total volume caught by capture fisheries. This milestone establishes aquaculture as the primary source of aquatic animals for human consumption worldwide.
This trend highlights the dramatic growth of farmed seafood, contrasting with wild capture fisheries production, which has remained relatively stable since the late 1980s. The consistent and accelerating growth of aquaculture has closed the production gap over the past few decades. The increased reliance on farming aquatic species demonstrates its increasing importance for global food security. Projections indicate a continued rise in aquaculture output, suggesting the ratio will widen further.
Defining Aquaculture Methods
Aquaculture operations employ different technical systems that vary widely in scale, location, and control over the growing environment.
Land-Based Systems
One of the oldest and most widespread methods is the use of land-based systems, such as ponds and raceways, often constructed as earthen or concrete structures. Pond systems typically use lower stocking densities and rely on natural productivity or supplemental feeding. Raceway systems are long, shallow channels that use a high volume of flowing water. These flow-through systems continuously introduce fresh water from a source and discharge it after a single pass.
Open Systems
Open systems, commonly known as net pens or cages, are moored in natural bodies of water like lakes, sheltered bays, or the open ocean. These floating enclosures allow for the free exchange of water, providing natural oxygen and removing waste. However, the fish are exposed to external environmental conditions and pathogens. The free exchange of water also presents risks of farmed fish escaping and the local accumulation of waste. Species like salmon and sea bass are often raised in these systems due to the cost-effectiveness of utilizing natural water bodies.
Recirculating Aquaculture Systems (RAS)
The most technologically advanced approach is the Recirculating Aquaculture System (RAS), a land-based, closed-loop method. RAS facilities continuously filter, treat, and reuse up to 99% of the water within an enclosed indoor environment. This approach integrates mechanical filters to remove solid waste and biological filters to convert toxic ammonia. The high degree of environmental control in RAS allows for optimal growing conditions, higher stocking densities, and minimal environmental discharge, making it possible to farm fish far from natural water sources.
Key Species and Geographic Dominance
The global aquaculture industry is highly concentrated, both in terms of the species produced and the regions responsible for the output. Freshwater finfish dominate the production landscape, with carps, barbels, and other cyprinids being the largest group by volume globally. Other prominent groups include red and brown seaweeds, which are primarily cultivated for human consumption and industrial uses. Tilapia and marine shrimp and prawns also rank among the top categories of farmed aquatic animals worldwide.
A small number of countries overwhelmingly dominate the world’s aquaculture production. Asia is the undisputed leader, accounting for approximately 70% of all aquatic animal production globally. Specifically, a group of just ten countries, including China, Indonesia, India, and Vietnam, are responsible for nearly 90% of the world’s total farmed aquatic production. China alone is the single largest producer, contributing over a third of the global total.
The massive production from these Asian nations underscores aquaculture’s role in supporting regional diets and economies. The scale of production highlights the sector’s capability to provide high-quality protein to a rapidly expanding global population. This concentration means that trends and practices in these few countries substantially influence the global seafood market and its environmental footprint.