Updated January 2022
The broad term “aquaculture” refers to the breeding, rearing, and harvesting of plants and animals in all types of water environments, including ponds, rivers, lakes, ocean, and artificial tanks. Using aquaculture techniques and technologies, researchers and the aquaculture industry are “growing", “producing", “culturing", and “farming” all types of freshwater and marine species.
Plants and animals grown via aquaculture are either released into the wild, transferred to ocean pens until grown to market value, or directly harvested for consumption. Aquaculture can be used to support commercial and recreational marine fisheries as well as to enhance or rebuild wild stock populations or coastal habitats, such as oyster reefs. Aquaculture also includes the production of ornamental fish for the aquarium trade and plant species used in a range of food, pharmaceutical, nutritional, and biotechnology products. There are also related industries such as equipment production, feed, and nutrition companies, and aquaculture consulting service firms that provide support to the global aquaculture industry.
Marine aquaculture or “mariculture” refers to the culturing of marine species, while freshwater aquaculture focuses on the culturing of freshwater species. For example, mariculture production includes oysters, clams, mussels, shrimp, and salmon, while freshwater aquaculture operations produce trout, catfish, and tilapia. Mariculture production can occur in the open ocean, an enclosed section of the ocean, or in tanks, ponds or raceways which are filled with seawater. An example of the latter is the farming of marine fish, including finfish, shellfish, and marine plants in saltwater ponds or land-based "closed-loop" circulation tanks.
Aquaculture has been practiced for hundreds of years in such diverse locations as Australia, China, Japan, Italy and Hawaii. In the United States, aquaculture in the form of freshwater fish hatcheries began in New York and Massachusetts in the 1860s.
According to the United Nations Food and Agriculture Organization (FAO), the world caught or produced over 171 million tons of fish in 2016—with more than 80 million tons (some 47 percent) coming from fish farms, including fresh-water operations on land and ocean farming close to shore. Interestingly, 20 million tons came from wild stocks mainly to be processed as feed stocks for fish farms, which is actually a reduction from previous years.
The largest aquaculture producers in the world are all in Asia, with China producing 57.8 of the global catch, Indonesia producing 12.9%, India producing 6.2%, Viet Nam producing 3.6%, and Bangladesh producing 2.1%, according to the 2019 Fisheries of the United States report. As a continent, Asia produced 91% of the global aquaculture catch in 2018.
In 2006, the FAO estimated that 2010 would mark the first year in human history that fish farms provided more seafood than all wild fisheries combined. Although aquaculture growth was not as large as predicted, aquaculture accounted for almost half of total global fish production (46.8 percent) in 2016 and growing. Despite this expansion, the overall industry growth rate has slowed from twelve percent per year to about six percent -- due mostly to a lack of suitable farming sites near shore, where the majority of today’s ocean farms are located. As a consequence, industry is looking farther out to sea. Advancing technologies and husbandry techniques are allowing farmers to grow fish and other seafood in environments that previously inaccessible or unsuitable just 20 years ago. Fish farms situated miles out at sea are viewed as a new frontier.
Open Ocean Aquaculture
Raising marine organisms under controlled conditions in exposed, high-energy ocean environments beyond significant coastal influence is a relatively new approach to mariculture. Open ocean aquaculture uses cages, nets, or long-line arrays that are moored, towed or float freely. Research and commercial open ocean aquaculture facilities are in operation or under development in Australia, Chile, China, France, Ireland, Italy, Japan, Mexico, US, and Norway.
The path to open ocean aquaculture has not been smooth. There have been several well-publicized disasters associated with the worldwide development of open ocean aquaculture. Chile was, until recently, the world’s largest producer of farmed salmon. Over the course of two decades, in the absence of strong environmental standards and national planning, the country massively expanded production of farmed Atlantic salmon. Soon after, the outsized industry was ravaged by disease, which spread rapidly across the pens densely packed with fish. Virtually overnight, production declined by half and thousands of jobs were lost. The consequences for the marine environment are still not known.
In 2017, the largest US based salmon open ocean aquaculture operation, owned by Cooke Aquaculture in WA, had an accidental release of 263,000 Atlantic salmon from one of its farms into the Pacific Ocean. Atlantic salmon is an exotic invasive species to the region, and many feared the potential for colonies to establish and cause severe alterations to the local ecosystem. The release was reportedly due to inadequate infrastructure maintenance by Cooke Aquaculture, and this fail resulted in the state of Washington banning the use of open ocean aquaculture for Atlantic salmon in 2018, phasing out the state's industry by 2025.
Aquaculture in the United States
Though aquaculture in the US is small compared to global operations, for four decades the US federal government has subsidized the development of aquaculture technologies. Starting with the passage of the 1966 National Sea Grant College Program Act, the government has consistently funded aquaculture research and full-time aquaculture staff through the 30 Sea Grant colleges across the US.
In 1998, NOAA began the National Marine Aquaculture Initiative focused on fish and shellfish farming in the ocean. The goals include a quintupling of total US production to $5 billion per year by 2020. In 2009, the Secretary of Commerce accepted a Fishery Management Plan developed by the Gulf of Mexico Fishery Management Council that would expand open-ocean aquaculture in the Gulf under the auspices of the nation’s primary fishery law, the Magnuson-Stevens Fishery Conservation and Management Act. NOAA Fisheries has developed a Gulf Aquaculture Plan that would allow up to 20 offshore aquaculture operations to be permitted in federal waters of the Gulf over a 10-year period. The proposed rule was published on August 28, 2014 and final rule was published on January 13, 2016. To date, almost all U.S. commercial facilities are sited in waters under state or territorial jurisdiction, with only the Catalina Sea Ranch farm growing shellfish and kelp in federal waters.
Additional domestic seafood production would tend to reduce the nation’s dependence on imports. Right now, the United States is a major importer of seafood – importing between 70% and 85% of seafood consumed. To note, some of the imported seafood was actually caught in US waters, but shipped elsewhere for processing before being imported back to the country. Over half of the seafood imported for consumption in the US is from aquaculture operations. Driven by imports, the U.S. seafood trade deficit has grown to over $16.9 billion annually – the highest it’s ever been.
The largest sector of the U.S. marine aquaculture industry is molluscan shellfish (oysters, clams, mussels), which accounts for 58% of total U.S. marine aquaculture production. The largest U.S. marine aquaculture species by weight is oysters, comprising 46% of total US production (~44.7M lb) followed by salmon at 37% (~36.4M lb) and clams at 11% (~10.8 M lb). Current production takes place mainly on land, in ponds, and in coastal waters under state jurisdiction. A smaller, more controversial sector is open ocean fin fish aquaculture, which after a period of growth, has experienced some recent community and political backlash. Alternatively, a fairly new aquaculture type that is growing in the U.S. is seaweed farming, with production growing 132% annually (at least from 2017 to 2018).
Many other countries are investing more heavily in aquaculture than the United States. According to NOAA's Office of Coastal Management, the United States ranked 16th in total aquaculture production in 2017, behind China, India, Vietnam, Thailand, Indonesia, Bangladesh, Japan, Chile, and Norway.
Technical, Scientific and Environmental Barriers to Expansion
With respect to marine aquaculture, the major barriers to expansion include:
- Clarifying the regulatory, enforcement, and environmental requirements for existing as well as new marine aquaculture operations, including uses of federal waters;
- Developing innovative technologies and management practices to ensure protection of marine ecosystems (see below); and
- Reducing costs and improving the efficiency and sustainability of different systems, including production in land-based and marine locations.
Like agriculture on land, the growth of a new aquaculture industry in the US will no doubt come with some degree of environmental impact. At present, much of the global aquaculture industry focuses on carnivorous and omnivorous fish in intensive operations (e.g., salmon). These fish are raised in a fashion analogous to livestock feedlots on land, a practice that has been widely criticized for its poor animal welfare and large environmental footprint: destroying habitat, endangering wild populations, and polluting watersheds.
In the ocean, fish farms are intimately connected to surrounding environments in ways that their counterparts on land are not—water freely flows in and through the net pens that contain the fish.
In reviewing the experience of ocean fish farming internationally, five types of environmental risk have been identified. Each should be addressed if there is to be environmentally responsible industry expansion in the US.
1. Pollution: Fish farms release fish waste, uneaten food, and chemical wastes directly into the ocean with significant potential consequences for the health of the water column and the seafloor below. Like the poultry farms of Maryland’s Eastern Shore, whose wastes flow into the Chesapeake Bay, such “over-enrichment” of coastal ecosystems has emerged as a major environmental problem, occasionally resulting in algal blooms, habitat loss, and the depletion of dissolved oxygen. Aquaculture should proceed only in ways that do not contribute to the problem of coastal eutrophication and nutrient loading (over-enrichment).
Additionally, both fish farms and commercial open ocean fishing can release harmful litter into the marine environment. Debris includes buoys, nets, lines, pots and more. To learn more about derelict fishing gear, check out this Surfrider blog, and this article by Coty Perry, which also includes additional information about the harms of overfishing.
2. Escaped Fish: Farmed fish can also escape from aquaculture operations. In 2017, the largest US based salmon open ocean aquaculture operation had an accidental release of 263,000 Atlantic salmon from one of its farms off Washington into the Pacific Ocean. The release was reportedly due to inadequate infrastructure maintenance by the owner, Cooke Aquaculture. In October 2009, 40,000 adult salmon escaped from Canada’s largest fish farm. From 2004 to 2008, Norwegian authorities reported cod escapes in excess of 800,000 fish. Annual escapes of farmed salmon in Norway ranged from 2 million fish to 10 million fish per year from 1995 to 2005.
Without careful management, the escape of fish species can compromise the genetic fitness of wild fish through interbreeding, competition, and more. In Europe and the US, there are already legitimate concerns that escaped Atlantic salmon could contribute to the eventual extinction of wild salmon populations. If the fish that escape are exotic, or are genetically modified, the risks increase considerably, with the potential to permanently upset ecosystem balance as these newly introduced fish out-compete, displace, or prey on native species, especially if they are able to colonize. Invasive species are listed second only to habitat destruction as a driver of extinction and are classified by the World Conservation Union as one of the four greatest threats to the world’s ocean. The kinds of fish and the ways in which they are farmed should be carefully controlled to ensure ocean ecosystems are not harmed by fish escapes from ocean fish farms.
3. Diseases, Parasites, and Chemicals: Ocean fish farms can amplify and spread deadly diseases and parasites into natural environments. For instance, white spot disease decimated the global shrimp farming industry in the 1990s. To address these threats, farm operators often apply drugs and chemicals, sometimes with subsequent harm to wild animals.
Today, infectious salmon anemia (ISA) is plaguing the salmon farming industry in Chile, leading to the intentional destruction of millions of farmed fish, with impacts confirmed on wild shrimp and likely on wild salmon. Several accounts have linked salmon farms to disease outbreaks in wild fish populations.
In recent years, there has been a dramatic spread of parasitic sea lice from farms to wild salmon at a cost of nearly $5 billion annually. As for chemicals, fish farmers are known to regularly apply pesticides, antibiotics, fungicides, anti-foulants, and other chemicals. These chemicals dissolve in the water and are carried outside the farms, sometimes with marked effects on surrounding ecosystems. Responsible aquaculture management should ensure that farms minimize the use of all drugs and chemicals, and that farms don’t grow to a scale at which they become reliant on regular use of such substances as has happened in other parts of the world.
4. Fish Meal and Fish Oil: Finfish aquaculture as it is currently practiced still consumes more animal protein than it produces as harvestable product. Each year, about 25 million metric tons of fish are “reduced” into fish meal and fish oil—roughly 30 percent of all wild fishery landings. A large portion of this goes to aquaculture, whose claim on global fish meal (68 percent) and fish oil (88 percent) is projected to grow further still. By some estimates, it requires 2-5 pounds of wild fish to produce a single pound of farmed salmon.
Improvements are bringing this ratio closer to one-to-one, but the growth of the global industry is outpacing these improvements. A major concern is that a heavy reliance on wild fish for feed will result in reduced prey for whales, dolphins, sharks, marine birds, and other important parts of marine food webs. For aquaculture to be more sustainable, it must substantially reduce its reliance on wild-caught fish for food and ensure that any remaining use comes from healthy, well-managed fisheries that protect marine food webs.
5. Predator Impacts: Cages full of captive fish will naturally draw predatory fish, marine mammals, diving birds, and other wildlife, and this attraction can lead to harmful consequences. In 2007, the Canadian government reported over 110 sea lions drowned in salmon cages, including one event that claimed over 50 animals. In other instances, farmers may harass or kill predators in an effort to protect their stocks. Responsible aquaculture should employ non-lethal deterrents as a primary course of action and should not unreasonably disrupt wildlife or their use of important marine habitats.
US Federal Government's Role in Aquaculture
To address the growing interest in and the issues related to marine aquaculture, the National Oceanic and Atmospheric Administration (NOAA) Fisheries launched a revived Aquaculture Program in 2004 to integrate and coordinate the agency’s aquaculture policies, research, outreach, and international obligations.
NOAA's aquaculture efforts are administered through a program office at NOAA Fisheries headquarters and encompass activities at NOAA Fisheries science centers and regional offices, NOAA's National Sea Grant program, and NOAA's National Ocean Service.
The vision of NOAA’s program is to foster sustainable aquaculture that will create employment and business opportunities in coastal communities; provide safe, sustainable seafood; and complement NOAA’s comprehensive strategy for maintaining healthy and productive marine populations, species, and ecosystems and vibrant coastal communities.
The program was instrumental in the development of the National Aquatic Animal Health Plan, the NOAA-USDA Alternative Feeds Initiative, the NOAA National Symposium on Shellfish and the Environment (2008), and the Integrated Multi-Trophic Aquaculture Workshop (2010).
NOAA Fisheries has also produced a 4-minute video that provides an overview of aquaculture in the United States.
Goals and Priorities
NOAA's Aquaculture Program addresses coastal and onshore marine aquaculture, as well as enhancement (hatchery) activities that support commercial and recreational fishing and the restoration of some endangered species. The priority areas of the program are Regulation and Policy, Science and Research, Outreach and Education, and International Activities.
The NOAA Aquaculture Program is guided by the policy objectives in the National Aquaculture Act of 1980 and the U.S. Department of Commerce Aquaculture Policy. The program is also guided by national fisheries and ocean legislation, including the Magnuson-Stevens Fishery Conservation and Management Act, the Coastal Zone Management Act, the Endangered Species Act, and the Marine Mammal Protection Act.
NOAA is working to address the technical and scientific issues related to development of marine aquaculture production in a number of ways. Since 1998, NOAA has funded a total of $15 million through the National Marine Aquaculture Initiative (NMAI), a competitive grants program coordinated by the NOAA Aquaculture Program and NOAA’s Office of Oceanic and Atmospheric Research. In the past NMAI has funded studies of candidate species, health and nutrition, best management practices, ecosystems monitoring and management, engineered production systems, and legal and operational frameworks.
NOAA also has marine aquaculture research capabilities at in-house laboratories within the Fisheries Service and the Ocean Service, and research and extension capabilities through state Sea Grant Programs. Research around the country on oysters, shrimp, crab, and other species has also helped to advance the state of marine aquaculture technology. In addition, aquaculture companies have received support for the development of commercial products and services through the Small Business Innovation Program at NOAA and the U.S. Department of Agriculture and, in the past, through the Saltonstall-Kennedy Program.
In February 2011 NOAA released a draft open-ocean aquaculture policy. The final policies from NOAA and the Department of Commerce were released in June 2011.
In July 2011 Representative Lois Capps (Santa Barbara, CA) introduced the National Sustainable Offshore Aquaculture Act of 2011 (House Resolution 2373). This bill would set a regulatory structure for offshore fish farming development while adopting a "balanced approach" to address environmental, social and economic issues. The legislation would also institute a research program to tackle significant data gaps and make sure offshore aquaculture development is ecologically sustainable.
Need for a National Framework
Currently, access to sites in coastal areas is often difficult as aquaculture must compete with many other coastal uses and secure numerous local, state, and federal permits. Resolving these siting issues is a primary driver for Marine Spatial Planning efforts that are currently taking place in several coastal states. Also, currently, there is no way to obtain a permit for aquaculture in federal waters under existing U.S. laws and regulations. Establishing a regulatory framework with rigorous environmental standards for federal waters was a recommendation by both the Pew Oceans Commission in 2003 and the U.S. Commission on Ocean Policy in 2004. In addition, the report Sustainable Marine Aquaculture: Fulfilling The Promise; Managing The Risks (January 2007) concluded:
- "Congress should enact legislation ensuring that strong environmental standards are in place to regulate the siting and conduct of offshore marine aquaculture."
- "Decisions about siting and permitting of marine aquaculture facilities should give priority to protection of the health of the marine environment in the face of uncertainty about effects on this public resource."
Despite the lack of such a regulatory framework, a Fishery Management Plan for Regulating Offshore Marine Aquaculture in the Gulf of Mexico was released by NOAA in February 2009.
The Environmental Law Institute (ELI), in collaboration with the Harvard Law School Emmett Environmental Law and Policy Clinic and The Ocean Foundation, has completed a comprehensive analysis of the application of the Clean Water Act to aquaculture in federal ocean waters. The resulting white paper reviews whether all offshore aquaculture facilities are or should be point sources requiring a discharge permit; considers EPA’s current Effluent Limitation Guidelines for aquaculture, including whether escaped fish are “pollutants;” and discusses how EPA may apply its Ocean Discharge Criteria to offshore aquaculture. Based on this analysis, the study makes recommendations for how EPA can improve its regulation of offshore aquaculture to ensure that it is effective, comprehensive, and predictable. Access the full report and accompanying fact sheet. More info.
Conclusions and A Path Forward
Aquaculture has the potential to play a significant role in meeting our growing demand for seafood. However, it is important that the US establish policies to ensure that the aquaculture industry grows sensibly and safely. In order for the US to be a leader in environmentally responsible open-ocean aquaculture, it should craft a unified national vision rather than accept the current fragmented regulatory arena.
Over the last decade, a number of high-level commissions and advisory bodies have made a range of recommendations concerning the principles and provisions of a coordinated, federal regulatory system for open-ocean aquaculture. The general consensus recommendations are for the United States to establish a comprehensive framework for open-ocean aquaculture that is rooted in the precautionary approach. Further, that framework should establish strong, legally-binding environmental standards for the development of the industry, while effectively protecting the broader public interest, preserving wild fish stocks and protecting ecosystems.
As articulated in Right from the Start, a recent report by Ocean Conservancy, four overarching principles of a responsible national open-ocean aquaculture policy can be summarized as follows:
Principle 1 – A Comprehensive Structure
Open-ocean aquaculture should proceed only under a comprehensive national framework, including new federal legislation, to guide the industry’s development. This framework should integrate with relevant national and state laws and regional ocean planning and management efforts. NOAA should be the primary regulatory agency enforcing Congress’s vision—with the duty of ensuring environmental protection while deciding whether, where and under what conditions to permit aquaculture in federal waters.
Principle 2 – A Precautionary Approach
Precaution must be the core operating principle for this new use of US ocean waters. Given the inherent risks and uncertainties, and the natural tension between economic development and preservation of public trust resources, the national framework must ensure vibrant marine ecosystems are protected to the maximum extent possible. The governing structure should permit open-ocean aquaculture only when independent, peer-reviewed science provides reasonable assurances that it will avoid negative impacts, including cumulative effects, on marine ecosystems.
Principle 3 – Rigorous Environmental Standards
The national framework must establish rigorous environmental standards to guide federal rulemaking and industry performance. These standards must address fish escapes, disease, pollution, chemicals, impacts on wildlife and predators, and reliance on wild fish for aquaculture feed. Standards should be performance-based and should regulate facility siting, permitting, monitoring, and enforcement. For maximum effectiveness, the standards should provide incentives to facilities for performance beyond permit requirements and significantly penalize facilities that fall short.
Principle 4 – Protect the Commons
The marine environment is a public trust resource held by the government for the benefit of all its citizens. In every respect, the development of open-ocean aquaculture should be subject to a full, meaningful public process. Expansion of fish farming into this environment should not proceed unless public resources are adequately protected, the public is fairly compensated for the use of its resources, and facility owners are held liable for damages to the marine environment.
The scientists who are working on an Ocean Health Index have published several articles concerning aquaculture, including Fish in, Fish Out--A Red Herring!, Aquaculture: (Not) Half the Fish We Eat, Inside the Mariculture Sub-Goal and Top Ten Amazing Aquaculture Facts.
- National Marine Fisheries Service. 2017. Fisheries of the United States, 2016. U.S. Department of Commerce, NOAA Current Fishery Statistics No. 2016. Available at: https://www.st.nmfs.noaa.gov/commercial-fisheries/ fus/fus16/index