Geoduck aquaculture

Geoduck aquaculture or geoduck farming is the practice of cultivating geoducks (specifically Pacific geoduck, Panopea generosa ) for human consumption . The geoduck is a wide edible saltwater clam , a marine bivalve mollusk , That is native to the Pacific Northwest .

Juvenile geoducks are planted or seeded on the ocean floor or the subtidal and subtidal soft areas, then harvested to marketable size (about 1 kg or 2.2 lbs). [1] They are native to the Pacific region of Baja California , through the Pacific Northwest and Southern Alaska . [2]

Most geoducks are harvested, but because of the state of the art, they may be harvested, [3] the need to grow geoducks to increase the geoduck aquaculture industry, particularly in Puget Sound, Washington . Geoduck meat is a prized delicacy in Asian cuisine; The majority of exports are China ( Shanghai , Shenzhen , Guangzhou , Beijing , are the main Chinese markets), Hong Kong and Japan . [4]


1. Washington State
Wild geoducks had been harvested in Puget Sound, Washington by residents and visitors for hundreds of years, but it was not until 1970 that the Washington Department of Natural Resources (WDNR) auctioned off the first right to commercially harvest wild geoducks. [5] Research into the viability of farming geoducks began in the 1970s. [6] In 1991, the development of hatchery and grow-out methods of brood stock were initiated. By 1996, commercial aquaculture had begun. As of 2011, there were 237 commercial sites operating on 145 ha of privately owned properties (including those owned by other private owners). [7] Commercial geoduck aquaculture has been primarily undertaken within the intertidal zone. [8]

2. British Columbia
Commercial Harvesting of Wild Geoducks Started in 1976. [9] In the early 1990s, the cultivation method was developed in British Columbia by Fan Seafoods Ltd. and the Underwater Harvesters Association (UHA), a group of 55 licensees. Holders for geoduck and horse clamfishery. The UHA used this method to initiate a wild geoduck enhancement program by subtidal areas with cultivated juvenile geoducks and continued supply in the wild. It even invented a mechanical seeder that crops juvenile geoducks on subtidal beds. DFO, Fan Seafoods Ltd., has been working with the provincial government’s Department of Fisheries and Oceans (DFO). and UHA, five pilot sites were selected in 1996 to study the feasibility of a geoduck aquaculture venture. [10] In 2007, the provincial government of UHA licensed to operate the first commercial geoduck farm on 25.3 ha off Hernando Island . [11]

3. Other areas
No geoduck aquaculture industry exists in Southern Alaska [12] and Mexico . [4] In New Zealand , Cawthron recently reported successful attempts at rearing juvenile geoducks. The plan is to plant in subtidal areas in order to supplement wild geoduck harvest. [13]

Geoduck species and their distribution

Panopea generosa is the geoduck that is found in the Pacific Northwest and Alaska . Panopea globosa , which is another species in the same genus, Panopea , is harvested in Mexico ‘s Gulf of California .

A small wild geoduck fishery exists in New Zealand for Panopea zelandica , the “deepwater clam”, and in Argentina for Panopea abbreviata , the “southern geoduck”. A fifth species, Panopea japonica , the Japanese geoduck, is found in Korea and Japan , but there is no viable commercial industry in these countries. [6]

Biomass densities in Southeast Alaska are estimated at various times in the world. [14] This estimate is used to predict the two percent allowed for commercial harvesting. [14]

Predators and diseases

Juvenile geoducks are likely to attack when predicted in their first year when they have not yet burrowed deeply into the substrate. Crabs , sea ​​stars , predatory gastropods , and flatfishes have been observed to feed on them. [6]Adult geoducks, which are already buried deep in the substrate, are out of reach of most predators except for sea ​​otters [12] and humans.

In 2012, no infectious diseases had been observed attacking cultured juvenile geoducks planted in the wild up to that point. [15] Surface abnormalities were observed in adult sex, but the pathogen or pathogens could not be identified. However, a protozoan parasite ( Isonema sp) was believed to be the causal agent of cultured geoduck larvae mortalities at a Washington State experimental hatchery. [16]

Production methods

The Washington Department of Fisheries (WDF) Point Whitney Laboratory pioneered research into the aquaculture of geoducks in 1970. The initial purpose of developing the techniques was to enhance the position of commercial fishing. Their first challenge was inducing spawning; the second challenge was the survival of the resulting larvae. [6] As per 2012, research into improving culture techniques is continuing, however, the basic environmental conditions for growth of geoducks have already been established.

Table 1. Summary of optimal biophysical parameters for geoduck culture (nursery and grow-out) [17]

Parameter Optimal Value
substrate mud / sand / pea gravel(penetration to 1m)
Depth 3-20 m
Temperature 8-18 C
Salinity 26-31 ppt
Transparency (Secchi) 2-> 10m
Current velocity <1.5 kn (<0.75 cm / s)
Productivity 15-200 mgC / m2 / day

The techniques for culturing geoducks are similar to that of other bivalves. Changes have been made by both academic and private laboratories through the years. [6]

Collection of broodstock

Geoducks spawn from spring to summer in the wild, peaking in June and July. Because of this timing, an equal number of male and female clams are collected starting in the early fall when gametogenesis starts. The clams are placed in milk and maintained in polyethylene with water (10-12 ° C) for several weeks. Microalgae is added as feed and regular cleaning is carried out to remove biodeposits.

Spawning method

Spawning is initiated by changing the seawater and increasing the amount of microalgae to increase the temperature of the water. The higher temperature and abundant supply of microalgal feeds spawning in males first, then in females.

Rearing of larvae

Fertilized geoduck eggs remain in the water column for 16 to 35 days until they metamorphose and settle on the substrate. As larvae, they are kept at a water temperature of 16 ° C and supplied with frequent water changes.

Growing-out method

Larger quantities of metamorphic fluid are collected at 15-17 ° C and supplied with microalgal feed. Metamorphosed larvae are characterized by the development of an attachment mechanism known as byssal threads .

Once byssal threads have developed, the clams are moved to a secondary nursery system that contains sand as the substrate . They are kept here until they are wide enough to be moved outdoors.

Tertiary nursery systems are made of large outdoor tanks or totes which have the same sand substrate and flowing seawater. The clams are kept in these systems until they reach a valve length of 5 mm, at which point they are ready to be planted.

Planting and seeding

Four to five juvenile geoducks are planted in PVC tubes that are “wiggled” into the sandy substrate along the intertidal zone during low tide. The PVC tubes are between 5 and 15 cm in diameter, with lengths from 20 to 30 cm, about 7 cm of which remain above the substrate. The plastic tubes are covered with a mesh net to protect the clams from predators. The tubes also serve to retain seawater at low tide, which prevents dehydration of the clams. [18] The following are some of the most important facts about the growth of these chemicals. Not all tidelands are suitable for geoduck aquaculture. The sand must be deep and clean, and the water must have the right salinityand degree of cleanliness. [19]

It shoulds ce jour restera That in Washington State, the aquaculture of geoducks OCCURS we intertidal lands, whereas in British Columbia, geoducks are cultured in subtidal areas, qui necessitates the growing of juvenile geoducks to at least 12 mm INSTEAD of 5 mm before planting. [17] Once planted in the subtidal bed, the area is covered by prediction (PVC tubes are not stable in subtidal beds due to strong currents ).


Mature geoducks are left to grow out until they are large enough to be marketable (1.0 kg). This can take from five to seven years. Wild and cultured geoducks are harvested by high pressure water. Once loosened, the clams are file Managed by hand and Placed in crates for transport to a processing facility.

Grading and packing

There is no standard grading system for quality, the color of the siphon (the whiter the better) and the size (up to 1 kg) are the main determiners of price. [4] Live geoducks are packed in coolers and shipped on the same day they are harvested.

Economic importance

The geoduck industry produces an estimated 6000 metric tons of clams annually, [4] of which only about 10-13% come from aquaculture. Washington is the largest producer of wild and cultured geoducks.

Table 2. Average Annual Production 2007-2010 [4]

leasing Production(in metric tones)
Wild Washington State 2143
British Columbia 1572
mexico 1094
Culture Washington State 591
British Columbia 75
Total 5823

Table 3. Difference between wild and cultured geoduck [4]

Wild Culture
crunchier whiter
hardier, travels better more uniform size
less water shrinkage thinner shell
may weigh 25% less than average wild geoduck

Major markets

China (Mainland and Hong Kong) is where 95% of geoducks exports are sent. [4] [20] Although the clams are priced at about $ 20 per pound at the point of origin, they can sell for $ 100 to $ 150 per pound at their destination. While exports to Japan have decreased in recent years, the market in China is expected to be soar.

Management of the industry

British Columbia

Environmental groups and citizens of British Columbia have had concerns about geoduck aquaculture operations in the province, even though the industry is still in its preliminary stages. They will have a lack of peer-reviewed studies on the impact of geoduck aquaculture practices. [11] Most concerned groups point to the situation in Puget Sound, Washington as an example of the environmental harm posed by geoduck farms. [21]Animal diseases, outbreaks of the disease, outbreaks of the disease, wildflies, wildflies, and other diseases of cultured geoducks. This procedure is apparently necessary because of the economics of the industry. [10]

The management of Canada’s aquaculture sector is headed by the Department of Fisheries and Oceans . The department shares this responsibility with 17 other departments and agencies at the federal and provincial levels. [22] The DFO works with these governments to “create the policy and ensure that the aquaculture industry develops in an environmentally responsible manner”. [23] In the case of wild geoduck fishery, the agency co-manages the activity with the Underwater Harvesters Association . [24]

In the Fisheries Act , the Navigable Waters Protection Act , and the Canadian Environmental Assessment Act . Other acts That control aquaculture practices include the Land Act , Health of Animals Act , Food and Drugs Act , Pest Control Products Act , and Species at Risk Act . [22] resulting from a total of 73 rules and regulations for the aquaculture industry; These rules and regulations have been described as being conflicting and contradictory. [25]The rules and regulations have been described as “one of the most heavily regulated in the world”. [26] A recent survey showed that Canadians support the creation of an Aquaculture Act that specifically addresses the needs of the industry. [27]The DFO collects fees from aquaculture licenses and leases, and receives government funding for its research programs. The UHA also funds research on geoduck aquaculture. [28]

To address consumer concerns regarding unsafe aquaculture practices, the DFO launched the Aquaculture Sustainability Reporting Initiative in 2011. [29] This report backs the Federal Sustainable Development Strategy implemented in 2010, and aims to provide its citizens with information on sustainable aquaculture practices that government agencies and the aquaculture industry are undertaking or plan to undertake. There are currently 29 participants in this initiative, coming from different sectors such as academia , the aquaculture industry, government agencies, and environmental organizations .

The Canadian government and the aquaculture industry Demonstrate sustainable practices by means clustering Several Such As federal ( Canadian General Standards Board ) and third-party certification ( International Organization for Standardization for traceability of Produce). [30] The Aquaculture Sustainability Reporting Initiative is modeled after the Global Reporting Initiative , which emphasizes reporting transparency and the accountability of an organization’s sustainability performance.

The DFO also recently released Aquaculture in Canada 2012: A Report on Aquaculture Sustainability in which it outlines its performance in terms of sustainability. The aquaculture industry has also taken steps to develop standards of practice. [31] In the case of geoduck, the UHA has adopted a labeling system (“Market Approved”) to ensure that it is safe to eat, of approved quality, and not illegally harvested. [32]

The DFO plans to undertake geoduck aquaculture in subtidal areas. No geoduck Production Currently OCCURS on private tidelands, ALTHOUGH conversion of other shellfish aquaculture ventures are operating tidelands to geoduck est regarded being white. There is no large-scale commercial production underway yet; ongoing trial farms are currently being studied and assessed. Some of the possible landings have been granted, but they have not been issued, except for the one granted to the UHA. [11]

Marketing and promotion When promoting its products, the Canadian aquaculture industry is responsible for all aspects of fish farming. The Canadian Aquaculture Industry Alliance has been awarded a DFO with a $ 1 M investment to promote awareness of the industry and increase sales. [33] The Aquaculture Innovation and Market Access Program (AIMAP) of the DFO promotes global competitiveness and environmental performance. [34] However, there is no formal marketing and promotion underway. Since its main market is China, this industry has relied on connections betweenVancouver -based export businesses with close ties to Hong Kong and Mainland China . The UHA however has been promoting geoducks in China with support from the federal government. [4]

Washington State

Concerns have also been raised regarding the impact of geoduck aquaculture on the natural habitat, particularly in Puget Sound . Currently, 80,000 acres of privately owned land are occupied by fishers in the United States. [1](Another report on the area at 141 ha [35] ). There are more and more countries in the world. some cases for the courts to arbitrate. The aquaculture companies do their own environmental codes of conduct and best management practices. [36]

The state government is considering leasing public aquatic lands (state-owned) specifically for geoduck aquaculture. [1] It currently leases 849 ha for aquaculture of other shellfish, such as oysters , other kinds of clams, and mussels . Fees are collected from aquaculture companies, and the result is used to manage and protect public waters throughout the state. Since its statehood in 1889, Washington had been selling tidelands to private individuals, initially as a source of revenue for the state. [37] By 1971, when this practice was stopped, the State had already 60% of public tidelands to private ownership. The state currently owns 1 million ha of aquatic lands.

Several states of aquatic life statutes [38] enacted under the Shoreline Management Act of 1971, entitled “Food and Commercial Use of the Aquatic Environment for Food Production, Fiber, Income, and Public Recreation of State-Owned Aquatic”. lands under its jurisdiction, and to this end of the world and the production and harvesting of seaweeds and sealife

Aquaculture is given priority in Washington: “The legislature finds that many areas of the state of Washington are scientifically and biologically suitable for aquaculture development, and therefore the legislature encourages the promotion of aquaculture activities, programs, and development. , programs, and development within the state “. [39] The National Oceanic and Atmospheric Administration (NOAA) is the lead agency for aquaculture. In February 2011, this agency released a draft of the National Policy for Sustainable Marine Aquaculture in the United States of Americathat aims to protect purpose, at the same time, utilize the nation’s aquatic resources in a sustainable way and encourages the growth of a sustainable aquaculture industry. [40]

Commercial aquaculture in Washington is regulated by local, state, and federal government entities, with each tasked with different responsibilities. Some of the agencies involved are the US Environmental Protection Agency , Department of Fisheries and Wildlife , US Army Corps of Engineers , and the Food and Drug Administration . The decisions of These agencies are by-governed Several federal acts, Such As the Clean Water Act , the Lacey Act , Federal Water Pollution Control Act , and Animal Health Protection Act . [36]

Because of the concerns raised by residents and environmental groups regarding the ecological impact of geoduck aquaculture, the WDNR has adopted a more comprehensive approach to leasing state-owned aquatic lands for geoduck aquaculture. In 2003, the state legislature instructed the WDNR to explore the feasibility of a geoduck aquaculture program on state-owned tidelands. [1] In 2007, the state passed House Bill 2220 on Shellfish Aquaculture [41]which, among other things, commissions the Washington Sea Grant (WSG) of the University of Washingtonto conduct “a series of scientific research studies that examine the potential effects, including the cumulative effects, of the current prevalent geoduck aquaculture techniques and practices on the natural environment in and around Puget Sound, including the Strait of Juan de Fuca”. The report is expected to end on December 1, 2013. The report is expected to be published on April 1, 2014. It also created the Shellfish Aquaculture Regulatory Committee , [42] ]which is composed of government agencies, aquaculture producers (2), concerned environmental organizations (2), and landowners (2). The role of the committee is to recommend guidelines and policies for shellfish aquaculture operations. In 2010, the WDNR tok a further step further by opening a dialogue with stakeholders and the public. They created an online forum on geoduck aquaculture to elicit concerns from residents, environmental groups and geoduck farm owners. [43]

Marketing and promotional Half of the geoducks Produced in Washington is Exported to Vancouver, BC . before being re-exported to the final markets in China and Hong Kong. The remaining half are exported to Seattle, WA and Anchorage, AK . [4] These three cities have the best connections to China and Hong Kong. Even though China is Washington’s biggest market for geoduck, there is little promotion from the state’s geoduck producers there. [4]

Washington Sea Grant studies

In the Washington State legislature, the WSG is conducting research

1. Geochemical and Ecological Consequences of Disturbances Associated with Geoduck Aquaculture Operations in Washington.

2. Cultured-Wild Interactions: Disease Prevalence in Wild Geoduck Populations.

3. Resilience of Soft-Sediment Communities after Geoduck Harvest in Samish Bay, Washington State.

The WSG released its most recent progress report in February 2012 on the possible effects of geoduck aquaculture on the environment. [44] The preliminary results of some of the studies appear to show that geoduck aquaculture does not negatively affect the natural habitat. One of the studies has been completed, and the results seemingly disruptive nature of harvesting geodesy has no effect on the infaunal benthic community . The report suggests that because of the effects of climate change and the effects of climate change, it does not affect them any differently. [45]This report, however, has some serious implications for which studies are not long-term, so the effect of geoduck aquaculture practices over many years can not be ascertained. [46]


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