Olympia Oyster (farmed)

Ostrea lurida

Sometimes known as Native Oyster or Oly.

This species is farm-raised.

Summary

Olympia Oysters are the native oyster in the northwestern U.S. and Canada. Around the turn of the century, populations were devastated by pollution and overfishing; and the hardier Pacific Oyster became the main cultivated oyster species in the region. In recent years, there have been efforts to seed areas with Olympias to reestablish wild beds. Size regulations make it illegal to take Olympia Oysters from the wild, so all Olympias in the market are farmed in origin. As with other bivalves, Olympia Oysters improve the quality of the surrounding water by filtering nutrients out of the water.

Criterion	Points
Inherent Operational Risks	2.50
Feed	3.75
Pollution	4.00
Risk to Other Species	3.00
Ecological Effects	2.75
Final Score (average of criteria)	3.20
Color

Final Score	Color
2.60 - 4.00
2.20 - 2.59
1.80 - 2.19
1.40 - 1.79
0.00 - 1.39

Last updated October 27, 2004.

Inherent Operational Risks

Core Points (only one selection allowed)

General System Design:

An aquaculture system's design is a good overall proxy measure for the likely effect of the operation on the environment. For example, open systems (e.g., net pens and net cages) are more likely to have pollution, disease, and escape issues than closed systems (e.g., recirculating tanks). With shellfish, which don’t require supplemental food input, the more important question is whether they are harvested on or off of the bottom.

1.00

This species is raised in a high risk system (e.g., net pens; net cages).

2.00

This species is raised in a moderate risk system (e.g., most ponds; raceways; bottom culture of mollusks).

Olympia Oysters represent a small portion of the total oysters raised in the United States, with only 1.5 mt reported by NMFS in 2002, compared with over 12,000 mt of American Oysters (Crassostrea virginica) and 4,500 mt of Pacific Oysters (Crassostrea gigas) (NMFS 2004). The Food and Agriculture Organization of the United Nations (FAO) reports 21 mt of farmed Olympia Oysters, and 11 mt of wild-caught Olympia Oysters coming from the United States in 2002 (FAO 2002). The discrepancy between the NMFS and FAO data is unclear, however the FAO estimate still represents a very small percentage of total oyster production in the U.S.

Olympia Oysters are native to the west coasts of the U.S. and Canada. Wild populations of these oysters are vulnerable to overfishing, and chemical and environmental disturbances. Additionally, in the mid to late 1800s, wild Olympia Oysters were overfished. Effluent from pulp mills at the turn of the century continued to decimate populations, and between 1890 and 1915, production decreased by over 90% (Downey 2004; Matthiessen 2001). After this precipitous drop, farmers began planting the hardier Pacific Oyster, which quickly replaced Olympias as the dominant oyster species in the northwest, both in the wild and in aquaculture operations (Matthiessen 2001; Downey 2004; PCSGA undated). In 1998, the Washington Department of Fish and Wildlife set restoration of the Olympia Oyster as a major priority. The Olympia Oyster Restoration Project has since taken over the role of coordinating the funding and volunteer efforts in the restoration of the species. These restoration efforts have seen survival rates from 25-95% depending on location, and are generally considered successful in aiding the recovery of the species (Peabody, pers. comm. 2004).

There is currently no catch of wild Olympia Oysters in public waters, including the wild populations that have been aided by restoration efforts. However, Olympia Oysters farmed on privately owned tidelands are marketed commercially, with Taylor Shellfish and the Olympia Oyster Company being two of the major producers (Peabody, pers. comm., 2004). These producers and most others raise Olympia Oysters on bottom. They also set naturally on farmed Pacific Oyster beds (PCSGA, undated).

3.00

This species is raised in a low risk system (e.g., re-circulating closed system; suspended culture of mollusks; zero-discharge ponds).

Points of Adjustment (multiple selections allowed)

-0.25	Species is raised at a high stocking density; OR there is a high density of sites in the geographic region, with evidence of environmental impact.
-0.25	Operations do not incorporate best-available, cost-effective technology to reduce environmental impact.
-0.25	There are no effective zoning or permitting practices for siting of facilities.
-0.25	Government programs encourage expansion of high-impact systems.

+0.25	Species is raised at a low stocking density OR there is a low density of sites in the geographic region, which results in minimal impact to the natural ecosystem. Olympia Oysters are not raised at high densities (Matthiessen 2001), and there is not a high density of farms. Currently, Olympia Oyster production is at a minimal commercial scale (PCSGA, undated).
+0.25	Operations incorporate innovative culture methods that limit environmental impacts (e.g., polyculture).
+0.25	There are effective zoning or permitting practices for siting and operation of facilities (e.g., mandatory consideration of hydrographic characteristics; requirements for site rotation). Washington, Oregon, California and British Columbia all have licensing controls for leasing land from the state/province. In Washington, most tidelands are privately owned, but aquatic farms must be registered through the State Department of Fish and Wildlife. All states’ shellfish farms are certified through a registered Shellfish Authority, which is usually the state's department of health or agriculture. Depending upon culture operations, shellfish farms may require various shoreline development or use permits through local county ordinances. Most shellfish aquaculture activities are permitted through the Army Corps of Engineers Nation Wide Permit 4 (Downey, pers. comm., 2004).
+0.25	Government programs preferentially encourage the expansion of low-impact systems over high impact systems.

2.50	Points for Inherent Operational Risks

Feed

Core Points (only one selection allowed)

Ecological Footprint of Feed:

"Trash" fish, frequently used in developing countries, is an industry term used to refer to whole fish or fish parts fed to farmed fish without being processed into fish meal and fish oil.

Twenty percent was selected as a cut-off because carnivorous species (e.g., salmon; eel; tuna; cobia; etc.) generally consume greater than twenty percent fish products (fishmeal, fish oil, or trash fish), while omnivorous or herbivorous species (e.g., catfish; tilapia; carps; etc.) consume less than twenty percent fish products.

1.00	Typical aquaculture feed includes high levels of fishmeal, fish oil, or "trash" fish (i.e., >20% of the feed; e.g., salmonid feeds).
2.00	Typical aquaculture feed includes moderate levels of fishmeal, fish oil, or "trash" fish (i.e., <20% of the feed; e.g., tilapia and catfish feeds).
3.00	No feed is used (e.g., mollusks and seaweeds) or typical aquaculture feed includes no fishmeal, fish oil, or "trash" fish (e.g., paddlefish; filter-feeding carps). No feed is used to farm Olympia Oysters, as they are filter-feeders, and get their nutrients from algae and other plankton in the water column (Matthiessen 2001).

Points of Adjustment (multiple selections allowed)

-0.25	When fish products are used, the major sources score low on the Wild-Caught Fisheries Ranking System.
-0.25	Feed contains greater than 10% of fish products and public or private sectors are not working to reduce fish content in feed.
-0.25	Feed conversion ratio (FCR) is high (i.e., >2.0; e.g., eel).
-0.25	Government policy promotes research, development and commercialization of carnivorous or other highly fishmeal-dependent species.

+0.25	When fish products are used, the major sources score high on the Wild-Caught Fisheries Ranking System; OR the source is innovative and ecologically sound (e.g., fisheries byproducts); OR no feed is used. No feed is used to raise farmed oysters(Matthiessen 2001).
+0.25	Feed contains less than 10% of fish products OR public and private sectors are working to reduce the fish content in feed; OR no feed is used. No feed is used to raise farmed oysters (Matthiessen 2001).
+0.25	Feed conversion ratio (FCR) is low (i.e., <1.3; e.g., salmon); OR no feed is used. No feed is used to raise farmed oysters (Matthiessen 2001).
+0.25	Government policy promotes research, development and commercialization of herbivorous species or other species not highly dependent on fishmeal.

3.75	Points for Feed

Pollution

Core Points (only one selection allowed)

Typical effluent treatment procedures:

1.00	Effluent is not treated before discharge (e.g., salmon net pens).
2.00	Effluent is partially treated before discharge (e.g., infrequently discharged effluent from catfish ponds).
3.00	Effluent is substantially treated before discharge (e.g., recirculating shrimp systems; settling ponds; reconstructed wetlands); OR treatment is not necessary because supplemental feed is not used (e.g., molluscs or seaweeds). Treatment of effluent is not necessary because supplemental feed is not used to farm Olympia Oysters (Matthiessen 2001).

Points of Adjustment (multiple selections allowed)

-0.25	Operations have demonstrated negative impacts on water quality or sediment/benthic characteristics (e.g., elevated nutrient levels; algal blooms; altered benthic communities).
-0.25	Pollutants (e.g., pesticides; parasiticides; antibiotics; plastic; nets; dead fish) are frequently discharged into the environment or otherwise not appropriately discarded.
-0.25	Effluent regulations do not exist, are lax, or are poorly enforced, which allows for degradation of the aquatic environment.
-0.25	Available technologies and practices to reduce or recycle waste (e.g., feed sensors; low-pollution feeds) are not used.

+0.25	Operations generally improve water quality or sediment/benthic characteristics (e.g., oyster farms). Oysters improve water quality by filtering out algae and other plankton, reducing levels of nitrogen, phosphorous and other nutrients (Downey, pers. comm. 2004).
+0.25	Chemicals (e.g., pesticides; parasiticides; antibiotics) are rarely or never used. Chemicals are not used in Olympia Oyster farming (Peabody, pers. comm. 2004).
+0.25	Robust water quality regulations exist (e.g., permits required; discharge caps; strong enforcement), and regular monitoring occurs. In general, no controls are necessary for effluent from Olympia Oyster operations, as the oysters are biofilters, and contribute to control of excess nutrients in the water column. However, water quality is monitored by the National Shellfish Sanitation Program, and in the event of contamination from harmful algal blooms (such as red tides) or bacteria, growing areas are closed to harvest to protect public health (Downey, pers. comm. 2004).
+0.25	Innovative methods and practices to reduce or recycle wastes are used (e.g., integrated systems; effluent and solid wastes used as terrestrial fertilizer); OR innovative methods and practices are not needed because raising this species does not create waste. Innovative methods and practices are not needed because raising this species does not create waste (Matthiessen 2001).

4.00	Points for Pollution

Risk to Other Species

Core Points (only one selection allowed)

Frequency and Impact of Escapes:

1.00	Farmed species regularly or intermittently escape into the wild AND escapes are non-native to the area or otherwise pose a risk to native populations or ecosystems (e.g., most non-native fish raised in outdoor facilities).
2.00	Escape frequency is not known OR farmed species is native to the area where it is raised and poses minimal risk to native populations or ecosystems (e.g., channel catfish in the US; most native mollusks). Olympia Oysters are native to the areas where they're farmed. Their natural range extends from Alaska to the southern tip of the Baja peninsula (Matthiessen 2001).
3.00	Farmed species never (or virtually never) escape to the wild (e.g., species is raised in bio-secure facilities).

Points of Adjustment (multiple selections allowed)

-0.25	This farmed species has been known to survive in the surrounding ecosystem if it escapes; OR would likely survive given its physiological requirements.
-0.25	This farmed species is known or is likely to compete with wild species for food or habitat if it escapes; OR this species is known or is likely to compromise the genetic integrity of the wild species (e.g., through spawning disruption, genetic introgression or establishment of feral stocks) if it escapes.
-0.25	This farmed species is known or is likely to amplify and transmit disease or parasites to wild populations (e.g., infectious salmon anemia or sea lice infestations) if it escapes.
-0.25	Regulatory authorities are not adequately addressing the risks of escape or spread of disease associated with farming this species.

+0.25	This farmed species has not been known to survive in the surrounding ecosystem if it escapes; OR would not likely survive given its physiological requirements; OR farmed species is a native mollusc. Olympia Oysters are a native mollusc.
+0.25	Operations employ management protocols and techniques to limit the ecological impacts of escaped farmed fish (e.g., triploidy; sterilization); OR it’s unlikely that escaped individuals will either compete with wild species for resources, or compromise the genetic integrity of wild species. It is unlikely that Olympia Oysters would compete with wild populations for resources or compromise the genetic integrity of wild species. First, they are a native species. Second, wild populations are at low levels of abundance and farming operations are at a low level of production (Matthiessen 2001). And third, broodstock for hatcheries or wild seed are collected from the areas where Olympia Oysters are planted, so their genetic makeup is similar to that of the wild populations (Olympia Oyster Company 2004; Peabody, pers. comm. 2004).
+0.25	Operations employ effective disease and parasite management protocols (e.g., fallowing of pens; retaining water when disease outbreak occurs); OR incidence of disease or risk of retransmitting disease is low. Incidence of disease is low (Downey, pers. comm. 2004).
+0.25	Regulatory authorities are addressing the risks of escape and spread of disease associated with farming this species. Several agencies are addressing the risk of escape and disease. Each state in the U.S. has a department of health or agriculture to oversee the transfer of shellfish between states under The National Shellfish Sanitation Program (NSSP) (Kraeuter and Castagna 2001). Agencies responsible for natural resource management (e.g., Washington Department of Fish and Wildlife) oversee the transfer of live animals intended for replanting (such as planting out seed from hatcheries to growing areas). Also, a health program, developed by the Pacific Shellfish Institute, provides stringent guidelines for hatcheries to assure disease-free seed is supplied to industry for grow-out (Downey, pers. comm., 2004).

3.00	Points for Risk to Other Species

Ecological Effects

Core Points (only one selection allowed)

Ecological sensitivity of site used for operations:

1.00	Operations are generally located in areas of high ecological sensitivity (e.g., coastal wetlands; mangroves).
2.00	Operations are generally located in areas of moderate ecological sensitivity (e.g., coastal and nearshore waters; rocky intertidal or subtidal zones; river or stream shorelines). Olympia Oyster farms are located in subtidal and intertidal zones, where the oysters can are generally submerged most of the time(Matthiessen 2001; Peabody, pers. comm., 2004). Manmade dikes have been used for about a century to retain seawater at low tide. These dikes create a buffer from extreme temperature variations (Olympia Oyster Company 2004).
3.00	Operations are generally located in areas of low ecological sensitivity (e.g., land that is less susceptible to degradation such as land formerly used for agriculture or land previously developed).

Points of Adjustment (multiple selections allowed)

-0.25	Farming this species causes substantial damage to surrounding habitat, ecosystem or other resources (e.g., groundwater depletion; stream diversion; saltwater intrusion; soil salinization; loss of habitat for juvenile fish; loss of flood control; dredging hard bottoms; etc.).
-0.25	Harmful or lethal predator deterrents are used (e.g., bird/seal shootings; acoustic deterrent devices); OR operation otherwise harms wildlife (e.g., dolphin/seal entanglement; disrupting migration routes; bird/animal shooting).
-0.25	If seed is collected from wild sources, the intensity of collection is high enough to result in depletion of brood stock, wild juveniles, or associated non-target organisms (e.g., collection of postlarvae shrimp).
-0.25	Government policy encourages aquaculture operations to locate or expand in areas of high ecological sensitivity.

+0.25	Operations enhance habitat structure or function (e.g., constructed wetlands). Like other bivalves, oysters enhance habitat function by improving water quality. Oysters filter out algae and other plankton, reducing levels of nitrogen, phosphorous and other nutrients. Farming oysters also enhances habitat structure that is integral in local ecosystems (Downey, pers. comm., 2004).
+0.25	Predator deterrents are not used OR predator deterrents are used but are not harmful or lethal (e.g., predator exclusion nets), AND operation does not otherwise harm wildlife. The major predators of Olympia Oysters include Oyster Drills (a type of snail) and sea stars. Planting above the tideline in tidal pools or where there is seepage minimizes mortality due to freezing and overheating, while reducing predation by sea stars (Peabody, pers. comm. 2004).
+0.25	Seed comes predominantly from hatcheries or on-farm sites (e.g., seed for trout); OR if seed is collected from the wild, it does not deplete brood stock, wild juveniles, or associated non-target organisms (e.g., collection of oyster or mussel spat). Producers use seed from hatcheries and naturally setting seed from wild populations. Where seed is hatchery raised, the broodstock is collected from the area where the oysters will be grown out (Downey, pers. comm. 2004; Peabody, pers. comm., 2004).
+0.25	Government policy encourages the growth of aquaculture operations in areas of low ecological sensitivity; OR protects sensitive habitats from aquaculture operations (e.g., prohibitions on cutting mangroves).

2.75	Points for Ecological Effects

References

Downey, Robin, Executive Director, Pacific Coast Shellfish Growers Association. Personal Communication. May 13, 2004 and September 27, 2004.

FAO Fisheries Department. 2002. Capture Production 1950-2002 and Aquaculture Production 1950-2002. Accessed via: Fishery Information. Data and Statistics Unit. FISHSTAT Plus: Universal software for fishery statistical time series.Version 2.3 (2000). Datasets accessed:

Matthiessen, George C. 2001. Oyster Culture. Fishing News Books, Blackwell Science Ltd. Great Britain.

National Marine Fisheries Service. Fisheries Statistics & Economics Division. Trade Data. Available online at: http://www.st.nmfs.gov/st1/index.html. Accessed September 23, 2004.

Olympia Oyster Company. History. Available online at: http://www.olympiaoyster.com/history.htm. Accessed September 27, 2004.

Pacific Coast Shellfish Growers Association. Undated. Profile of the Pacific Coast Shellfish Farming Industry.

Peabody, Betsy. Olympia Oyster Restoration Project. Personal Communication. September 27, 2004.