Environmental Safeguards for Open-Ocean Aquaculture

Expanding aquaculture into federal waters should not be promoted without enforceable national guidelines for the protection of marine ecosystems and fisheries.

Because of continued human pressure on ocean fisheries and ecosystems, aquaculture has become one of the most promising avenues for increasing marine fish production. During the past decade, worldwide aquaculture production of salmon, shrimp, tuna, cod, and other marine species has grown by 10% annually; its value, by 7% annually. These rates will likely persist and even rise in the coming decades because of advances in aquaculture technology and an increasing demand for fish and shellfish. Although aquaculture has the potential to relieve pressure on ocean fisheries, it can also threaten marine ecosystems and wild fish populations through the introduction of exotic species and pathogens, effluent discharge, the use of wild fish to feed farmed fish, and habitat destruction. If the aquaculture industry does not shift to a sustainable path soon, the environmental damage produced by intensive crop and livestock production on land could be repeated in fish farming at sea.

In the United States, aquaculture growth for marine fish and shellfish has been below the world average, rising annually by 4% in volume and 1% in value. The main species farmed in the marine environment are Atlantic salmon, shrimp, oysters, and hard clams; together they account for about one-quarter of total U.S. aquaculture production. Freshwater species, such as catfish, account for the majority of U.S. aquaculture output.

The technology is in place for marine aquaculture development in the United States, but growth remains curtailed by the lack of unpolluted sites for shellfish production, competing uses of coastal waters, environmental concerns, and low market prices for some major commodities such as Atlantic salmon. Meanwhile, the demand for marine fish and shellfish continues to rise more rapidly than domestic production, adding to an increasing U.S. seafood deficit (now about $8 billion annually).

The U.S. Department of Commerce has articulated the need to reverse the seafood deficit, and under the leadership of its subagency, the National Oceanic and Atmospheric Administration (NOAA), has a stated goal of increasing the value of the U.S. aquaculture industry from about $1 billion per year currently to $5 billion by 2025. In order to achieve this goal, the Department of Commerce has set its sights on the federal waters of the Exclusive Economic Zone (EEZ), located between the 3-mile state zone and 200 miles offshore, where the potential for aquaculture development appears almost limitless. The United States has the largest EEZ in the world, amounting to 4.5 million square miles, or roughly 1.5 times the landmass of the lower 48 states. Opening federal waters to aquaculture development could result in substantial commercial benefits, but it also poses significant ecological risks to the ocean—a place many U.S. citizens consider to be the nation’s last frontier.

On June 8, 2005, Commerce Committee Co-Chairmen Sens. Ted Stevens (R-AK) and Daniel Inouye (D-HI) introduced the National Offshore Aquaculture Act of 2005 (S. 1195). The bill, crafted by NOAA, seeks to support offshore aquaculture development within the federal waters of the EEZ; to establish a permitting process that encourages private investment in aquaculture operations, demonstrations, and research; and to promote R&D in marine aquaculture science and technology and related social, economic, legal, and environmental management disciplines. It provides the secretary of Commerce with the authority and broad discretion to open federal waters to aquaculture development, in consultation with other relevant federal agencies but without firm environmental mandates apart from existing laws. The bill’s proponents argue that fish farming in the open ocean will relieve environmental stress near shore and protect wild fisheries by offering an alternative means of meeting the rising demand for seafood. However, because it lacks a clear legal standard for environmental and resource protection, the bill’s enactment would likely lead to a further decline in marine fisheries and ecosystems.

The introduction of S. 1195 came as no surprise to the community of environmental scientists and policy analysts who have followed the development of aquaculture in the United States. In 1980, Congress passed the National Aquaculture Act to promote aquaculture growth, and in the process established the Joint Subcommittee on Aquaculture, an interagency body whose task was to provide coordination and seek ways to reduce regulatory constraints on aquaculture development. Despite these actions, local concerns and associated regulatory burdens have limited the expansion of marine aquaculture within the 3-mile jurisdiction of many states, and regulatory uncertainty has discouraged investment in offshore production between the 3-mile state zone and the 200-mile EEZ. The Bush administration is now prepared to support efforts to streamline regulatory authority within the federal waters of the EEZ, promote open-ocean aquaculture, and make the United States a more competitive producer of marine-farmed fish.

Implementing S. 1195 would involve a two-tiered process: first, the creation of a law authorizing the leasing and permitting of open-ocean aquaculture facilities by the secretary of Commerce; and second, the start of rulemaking procedures within and among federal agencies. If passed, the bill would allow NOAA to issue site and operating permits within federal waters with 10-year leases, renewable for 5year periods. Decisions on permit applications would be granted within 120 days and would not require a lengthy inventory process to assess the state of marine resources at each site. The proposed legislation requires NOAA to “consider” environmental, resource, and other impacts of proposed offshore facilities before issuing permits; however, there is no requirement that NOAA actually identify and address those impacts before the permits and leases are granted. Similarly, the bill does not require that, during the permitting process, NOAA weigh the risks to the marine environment against the commercial benefits of aquaculture development.

The pro–fish-farming language of S. 1195, without commensurate language on the conservation of ocean resources and ecosystems, is extremely worrisome. It is unlikely that ocean resources will be protected in the face of aquaculture development unless the statute requires specific language on environmental mandates—not just “considerations”—for the rulemaking and permitting processes.

Open-ocean aquaculture encompasses a variety of species and infrastructure designs; in the United States, submersible cages are the model used for offshore finfish production. These cages are anchored to the ocean floor but can be moved within the water column; they are tethered to buoys that contain an equipment room and feeding mechanism; and they can be large enough to hold hundreds of thousands of fish in a single cage. Robotics are often used for cage maintenance, inspection, cleaning, and monitoring. Submersible cages have the advantage of avoiding rough water at the surface and reducing interference with navigation. A major disadvantage of offshore operations is that they tend to be expensive to install and operate. They require sturdier infrastructure than near-shore systems, they are more difficult to access, and the labor costs are typically higher than for coastal systems.

The economic requirements of open-ocean aquaculture suggest that firms are likely to target lucrative species for large-scale development or niche markets. In the United States, moi is produced commercially far from shore in Hawaii state waters, and experiments are being conducted with halibut, haddock, cod, flounder, amberjack, red drum, snapper, pompano, and cobia in other parts of the country. Tuna is another likely candidate for offshore development. Altogether, about 500 tons of fish are currently produced each year in submersible cages in the United States, primarily within a few miles of shore. The technology appears to have real promise, even though it is not yet economically viable for commercial use in most locations, and it is not yet deployed widely in federal waters far from shore.

Opening far-offshore waters to aquaculture could lead to substantial commercial benefits, but it also poses significant ecological risks to the ocean—a place many U.S. citizens consider to be our last frontier.

Some of the species now farmed in open-ocean cages, such as bluefin tuna, Atlantic cod, and Atlantic halibut, are becoming increasingly depleted in the wild. Proponents of offshore aquaculture often claim that the expansion of farming into federal waters far from shore will help protect or even revive wild populations. However, there are serious ecological risks associated with farming fish in marine waters that could make this claim untenable. The ecological effects of marine aquaculture have been well documented, particularly for near-shore systems, and are summarized in the 2005 volumes of the Annual Review of Environment and Resources, Frontiers in Ecology (February), and BioScience (May). They include the escape of farmed fish from ocean cages, which can have detrimental effects on wild fish populations through competition and interbreeding; the spread of parasites and diseases between wild and farmed fish; nutrient and chemical effluent discharge from farms, which pollutes the marine environment; and the use of wild pelagic fish for feeds, which can diminish or deplete the low end of the marine food web in certain locations.

Because offshore aquaculture is still largely in the experimental phase, its ecological effects have not been widely documented, yet the potential risks are clear. The most obvious ecological risk of offshore aquaculture results from its use of wild fish in feeds, because most of the species being raised in open-ocean systems are carnivorous. If offshore aquaculture continues to focus on the production of species that require substantial quantities of wild fish for feed—a likely scenario because many carnivorous fish command high market prices—the food web effects on ecosystems that are vastly separated in space could be significant.

In addition, although producers have an incentive to use escape-proof cages, escapes are nonetheless likely to occur as the offshore industry develops commercially. The risks of large-scale escapes are high if cages are located in areas, such as the Gulf of Mexico, that are prone to severe storms capable of destroying oil rigs and other sizeable marine structures. Even without storms, escapes frequently occur. In offshore fish cages in the Bahamas and Hawaii, sharks have torn open cages, letting many fish escape. In addition, farming certain species can lead to large-scale “escapes” from fertilization. For example, cod produce fertilized eggs in ocean enclosures, and although ocean cages are more secure than near-shore net pens, neither pens nor cages will contain fish eggs. The effects of such events on native species could be large, regardless of whether the farmed fish are within or outside of their native range. At least two of the candidate species in the Gulf of Mexico (red drum and red snapper), as well as cod in the North Atlantic, have distinct subpopulations. Escapes of these farmed fish could therefore lead to genetic dilution of wild populations, as wild and farmed fish interbreed.

The main problem with the proposed legislation is the broad discretion given to the secretary of Commerce to promote offshore aquaculture without clear legal standards for environmental protection.

Offshore aquaculture also poses a risk of pathogen and parasite transmission, although there is currently little evidence for disease problems in offshore cages. In general, however, large-scale intensive aquaculture provides opportunities for the emergence of an expanding array of diseases. It removes fish from their natural environment, exposes them to pathogens that they may not naturally encounter, imposes stresses that compromise their ability to resist infection, and provides ideal conditions for the rapid transmission of infectious agents. In addition, the production of high-valued fish often involves trade in live aquatic animals for bait, brood stock, milt, and other breeding and production purposes, which inevitably results in trans-boundary spread of disease. The implications of open-ocean farming for pathogen transmission between farmed and wild organisms thus remains a large and unanswered question. Moreover, pathogen transmission in the oceans is likely to shift in unpredictable ways in response to other human influences, particularly climate change.

Even the claim that open-ocean aquaculture provides “a dilution solution” to effluent discharge may be disputed as the scale of aquaculture operations expands to meet economic profitability criteria. The ability of offshore aquaculture to reduce nutrient pollution and benthic effects will depend on flushing rates and patterns, the depth of cage submersion, the scale and intensity of the farming operations, and the feed efficiency for species under cultivation. Scientific results from an experimental offshore system in New Hampshire indicate no sedimentation or other benthic effects, even when the cages are stocked with more than 30,000 fish. However, commercial farms will likely have 10 or more times this density in order to be economically viable; commercial salmon farms commonly stock 500,000 to a million fish at a site. It is not a stretch to imagine a pattern similar to that of the U.S. industrial livestock sector, with large animal operations concentrated near processing facilities and transportation infrastructure, and in states with more lenient environmental standards.

An essential question in the debate thus remains: What is the vision of the Department of Commerce in developing offshore aquaculture? If the vision is to expand offshore production to a scale sufficient to eliminate the $8 billion seafood deficit, the ecological risks will be extremely high.

In 2003 and 2004, the U.S. Commission on Ocean Policy and the Pew Oceans Commission completed their reports on the state of the oceans and suggested various policy reforms. Both reports acknowledged the rising role of aquaculture in world markets, described its effects on ocean ecosystems, and recommended NOAA as the lead federal agency to oversee marine aquaculture in the United States. The main difference between the reports is captured in the recommendations. Whereas the U.S. Commission recommended that the United States pursue offshore aquaculture, acknowledging the need for environmentally sustainable development, the Pew Commission recommended a moratorium on the establishment of new marine farms until comprehensive national environmental standards and policy are established. The drafting of S. 1195 clearly follows the U.S. Commission approach but uses even weaker environmental language, which allows for multiple interpretations and no clear mandate on marine resource and ecosystem protection.

The main problem with the proposed legislation is the broad discretion given to the secretary of Commerce to promote offshore aquaculture without clear legal standards for environmental protection. The authority is intended to facilitate a streamlining of regulations, yet it provides minimal checks and balances within the system. The bill states that the secretary “shall consult as appropriate with other federal agencies, the coastal states, and regional fishery councils . . . to identify the environmental requirements applicable to offshore aquaculture under existing laws and regulations.” An implicit assumption of the bill is that most of the needed environmental safeguards are already in place. Additional environmental regulations targeted specifically for offshore aquaculture are to be established in the future “as deemed necessary or prudent by the secretary” in consultation with other groups. Yet timing is everything. If the law is passed without the establishment of comprehensive national guidelines for the protection of marine species and the environment— and the requirement that these guidelines be implemented— such protection may never happen, or it may happen after irreversible damages have occurred.

Are current federal laws sufficient to protect the environment in the EEZ? The answer is no. As a framework, they leave major gaps in environmental protection. The Rivers and Harbors Act gives the Army Corps of Engineers the authority to issue permits for any obstruction in federal waters (including fish cages) but does not provide clear environmental mandates. The Corps has the broad discretion to ensure environmental quality but is not required to do so. The Outer Continental Shelf Lands Act extends this authority farther offshore beyond the territorial waters of the EEZ and applies to any offshore facilities that are anchored on or up to 1 mile from offshore oil rigs; in this case, further permit approval is required from the Department of Interior. The Clean Water Act gives the Environmental Protection Agency (EPA) the authority to regulate waste discharges from aquaculture facilities, but the agency’s recent effluent guidelines for aquaculture net pens, which presumably would be applied to offshore cages, focus simply on the use of best management practices. Aquaculture discharge is not currently regulated through the National Pollution Discharge Elimination System (NPDES), the permitting system used for municipal and industrial point-source discharge to U.S. waters. The Endangered Species Act and the Marine Mammal Protection Act both are applicable in the EEZ and can be used to limit offshore aquaculture operations if they are proven to threaten any listed threatened or endangered species, or if they unlawfully kill marine mammals. In addition, the Lacey Act gives the U.S. Fish and Wildlife Service the authority to regulate the introduction of exotic species in federal waters if they have been listed specifically as “injurious” to other species. The Lacey Act applies to any species that are transported or traded across borders, but not to species that already exist within borders. Finally, all international treaties and protocols would apply to offshore aquaculture in the EEZ.

The only federal law that the proposed bill would explicitly supersede is the Magnuson-Stevens Act (MSA) of 1976, which stipulates a balance between fishing and conservation. S. 1195 does not include any specific balancing requirements between ecosystems and industry. Regional fishery management councils established under the MSA as well as the public would be consulted in the process of environmental rulemaking but would not have a determining effect on the outcome.

Although S. 1195 supersedes only one federal law, existing legislation does not adequately address the major risks of farmed fish escapes and genetic dilution of wild stocks, pathogen transmission from farms to wild organisms, and cumulative effluent discharge. Most existing laws and regulations for marine aquaculture are found at the state level, where current near-shore systems operate. Few states have comprehensive regulatory plans for marine aquaculture, and there are no regional plans that address the risks of biological, chemical, or nutrient pollution that spreads from one coastal state to the next.

The proposed bill gives coastal states an important role in influencing the future development of offshore aquaculture. Indeed, coastal states would be permitted to opt out of offshore aquaculture activities. The bill states that offshore aquaculture permits will not be granted or will be terminated within 30 days if the secretary of Commerce receives written notice from the governor of a coastal state that the state does not wish to have the provisions of the act apply to its seaward portion of the EEZ. The governor can revoke the opt-out provision at any time, thus reinstating NOAA’s authority to issue permits and oversee aquaculture operations in that portion of the EEZ. Although the bill does not grant coastal states any jurisdiction over that part of the EEZ, it does provide them with potential exclusion from offshore aquaculture activities.

This amendment ensures a role for coastal states that is stronger than that which would apply through the Consistency Provision (section 307) of the Coastal Zone Management Act (CZMA). Section 307 of the CZMA requires that federally permitted projects be consistent with select state laws that safeguard coastal ecosystems, fisheries, and people dependent on those fisheries (collectively called the state’s “coastal zone management program”). To complete the permitting process for an offshore aquaculture project, the project applicant must certify the project’s consistency with the state’s coastal zone management program to NOAA. Even if the state objects to the applicant’s consistency certification, the secretary of Commerce can override the state’s objection and issue the permit simply by determining that the project is consistent with the objectives or purposes of the Federal Coastal Management Act or that the project is necessary in the interest of national security. Thus, the Department of Commerce retains ultimate authority over whether state laws apply to the EEZ.

Although the decision by different coastal states to opt out of the proposed offshore aquaculture bill is yet to be determined, some states have already adopted policies related to aquaculture development within state waters. In Alaska, state law prohibits finfish farming within the 3-mile state zone. In Washington, House Bill 1499 allows the Washington Department of Fish and Wildlife to have more control over environmental damages caused by near-shore salmon farming. In California, salmon farming and the use of genetically modified fish are prohibited by law in marine waters, and a new bill currently being reviewed in the state assembly (SB. 210) requires strict environmental standards for all other forms of marine aquaculture introduced into state waters. The California legislation, in particular, provides an excellent model for a redrafting of the National Offshore Aquaculture Act.

The need for national environmental standards

Whether environmentalists like it or not, marine aquaculture is here to stay and will inevitably expand into new environments as global population and incomes grow. Although the United States is in a position to make itself a global model for sustainable fish production in the open ocean, the proposed bill unfortunately falls far short of this vision. Pursuant to the recommendations of the Pew Commission, an aggressive marine aquaculture policy is needed at the national level to protect ocean resources and ecosystems. Within this policy framework, several specific features are needed:

  • The establishment of national environmental standards for siting and operation that minimize adverse effects on marine resources and ecosystems and that set clear limits on allowable ecological damage.
  • The establishment of national effluent guidelines through the EPA for biological, nutrient, and chemical pollution from coastal and offshore fish farms, using NPDES permits to minimize cumulative effluent impacts.
  • The establishment of substantive liability criteria for firms violating environmental standards, including liability for escaped fish and poorly controlled pathogen outbreaks.
  • The establishment of rules for identifying escaped farm fish by their source and prohibiting the use of genetically modified fish in ocean cages.
  • The establishment of a transparent process that provides meaningful public participation in decisions on leasing and permitting of offshore aquaculture facilities and by which marine aquaculture operations can be monitored and potentially closed if violations occur.
  • The establishment of royalty payments process for offshore aquaculture leases that would compensate society for the use of public federal waters.

At the same time, firms exceeding the minimum standards should be rewarded, for example, through tax breaks or reductions in royalty fees, in order to encourage environmental entrepreneurship and international leadership. By articulating a comprehensive set of environmental standards and incentives within the draft of the law, the bill would gain acceptance by a broad constituency interested in the sustainable use of ocean resources.

Proponents of offshore aquaculture might argue that these recommendations hold the industry to exceedingly high standards. Yes, the standards are high, but also essential. There is now a widespread realization that the ability of the oceans to supply fish, assimilate pollution, and maintain ecosystem integrity is constrained by the proliferation of human activities on land and at sea. Offshore aquaculture could help to alleviate these constraints, but only if it develops under clear and enforceable environmental mandates.

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Cite this Article

Naylor, Rosamond L. “Environmental Safeguards for Open-Ocean Aquaculture.” Issues in Science and Technology 22, no. 3 (Spring 2006).

Vol. XXII, No. 3, Spring 2006