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Thirty Years of Sea Ranching Manila Clams (Venerupisphilippinarum): Successful Techniques and LessonsLearnedPeter Becker a; Carl Barringer a; Dan C. Marelli ba Little Skookum Shellfish Growers LLC, Shelton, Washington, USAb Florida Fish and Wildlife Conservation Commission, Florida Fish and WildlifeResearch Institute, St. Petersburg, Florida, USA

Online Publication Date: 01 January 2008To cite this Article: Becker, Peter, Barringer, Carl and Marelli, Dan C. (2008) 'ThirtyYears of Sea Ranching Manila Clams (Venerupis philippinarum): SuccessfulTechniques and Lessons Learned', Reviews in Fisheries Science, 16:1, 44 - 50To link to this article: DOI: 10.1080/10641260701790259

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Reviews in Fisheries Science, 16(1–3):44–50, 2008Copyright C©© Taylor and Francis Group, LLCISSN: 1064-1262 printDOI: 10.1080/10641260701790259

Thirty Years of Sea Ranching ManilaClams ( Venerupis philippinarum ):Successful Techniques and LessonsLearned

PETER BECKER,1 CARL BARRINGER,1 and DAN C. MARELLI2

1Little Skookum Shellfish Growers LLC, Shelton, Washington, USA2Florida Fish and Wildlife Conservation Commission, Florida Fish and Wildlife Research Institute, St. Petersburg,Florida, USA

Successful intertidal mollusk farming requires a working knowledge of the biology, density, dynamics, and distributionof mollusk populations. Little Skookum Shellfish Growers (LSSG) has operated under economically and environmentallysustainable sea ranching guidelines for Manila clams (Venerupis philippinarum) since 1977 in Little Skookum Inlet nearShelton, Washington, USA. LSSG’s system of benthic surveys and seeding offers a rational approach for establishing andmonitoring standing stocks and biomass dynamics of infaunal mollusk populations, allowing LSSG to sea ranch Manilaclams in excess of 60,000 kg/ha/y in sustainable yield. Until successful acoustical methods for infaunal biomass analysisare established, this approach may be the only cost effective way of achieving economical and sustainable results with a fullworking knowledge of the impacts involved in either intertidal sea ranching or stock enhancement for infaunal mollusks.

Keywords aquaculture, Manila clams, Venerupis phillipanarum, management, sea ranching

INTRODUCTION

Culture of bivalve shellfish is practiced worldwide and has along history both in western and Asian societies. Aquacultureoperations using bivalves, or clam farms, involve a number ofspecies in the general categories of clams, oysters, mussels, andscallops. Reasons for culturing bivalves rather than relying onthe harvest of wild populations include overharvest of traditionalshellfish populations, loss of shellfish grounds to pollution orother human impacts, and greater rates of production in cultureoperations than with wild harvest operations. Other reasons forculturing bivalves include restoration or enhancement of wildpopulations that may be depleted or endangered.

For the clam farmer, the raison d’etre is straightforward: theclam farmer needs to generate enough profit to support his orherself and his or her family and to ensure the continuance ofthe clam farm through upkeep and maintenance of equipment,payment of wages, benefits, and insurance for employees, and

Address correspondence to Peter Becker, Little Skookum Shellfish Grow-ers, 2262 SE Lynch Road, Shelton, WA 98584, USA. E-mail: marketing@skookumshellfish.com

other costs associated with operating a successful business. Aswith any business, there are financial concerns beyond the dailyoperation, including the market value of a business or the abilityto raise capital for investment in the business when warranted.And although artisanal culture operations that rely on naturalprocesses and intensive manual labor are viable in some partsof the world, operations in the United States and other westernnations cannot afford to rely on these methods if they are tosurvive in modern economic climates. For these reasons, clamfarmers in the United States must be actively involved in mak-ing accurate predictions of harvest quantities and taking steps toensure that these predictions are somewhat accurate. This con-cept is very similar to a row-crop farmer who estimates area inproduction, estimated yield, and makes predications based onmarket value of crops. Predictions made by the farmer becomevery important to bankers and insurance professionals as wellas the farmer. Through time, a row-crop farmer can increaseproduction by increasing the area in production or increasingyields through a variety of means, and we suggest that the clamfarmer can address the challenge of maintaining or increasingproduction in a similar manner.

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SUCCESSFUL TECHNIQUES AND LESSONS LEARNED 45

It is an unusual artifact of the history of the United Statesof America, Federal Territory of Washington (1853–1898), andlater the United States of America, State of Washington (from1898 to the present) that intertidal, and in some cases subtidal,lands may be privately owned (Revised Code of Washington). In1976, the author (Becker) was given the opportunity to developan aquaculture project on a 3-ha intertidal site of a 95-year-old, privately owned, oyster and clam harvest area. In LittleSkookum Inlet near Shelton, Washington, we (Becker and Bar-ringer) created the Little Skookum Shellfish Growers (LSSG).We developed new guidelines for an economically and envi-ronmentally sustainable sea ranch for Manila clams (Venerupisphilippinarum)∗ and have continued to operate the LSSG underthese guidelines for 30 years.

Venerupis philippinarum is a nonindigenous species that wasaccidentally introduced into Little Skookum Inlet sometime after1937 along with Pacific oyster (Crassostrea gigas). Venerupisphilippinarum became established in the inlet as it has elsewhere,and in Little Skookum this clam appears to exist in an ecologicalniche that compliments that of the most abundant of the nativeclams (Protothaca staminea).

The harvest area is a tidal water body running northwestwardfrom Totten Inlet for about 5 km and has a width of no morethan 1 km. Clams are harvested from the intertidal beach, whichextends from –0.8 ft below mean lower low water (MLLW) to+7.5 ft above MLLW (–0.24 m to +2.29 m). The beach consistsof a mixture of 20% sand, 30% shell hash, and 50% pea gravel.The previous owner had operated the site for 42 years for wildharvest of native littleneck clams (Protothaca staminea) andfor the culture of native Olympia oysters (Ostrea conchaphila,Carpenter, 1857), so the composition of the sediment must beconsidered somewhat altered from a natural condition. Since1937, the area was used as rearing area for cultched seed of thePacific Oyster (Crassostrea gigas) imported from Japan. It wasdetermined that the area encompassed by the LSSG should stayin bivalve culture and that the most economically appropriatespecies should be emphasized.

The goal of the LSSG was to use scientific methods to surveyand monitor the bivalve population in the culture area and toestablish a target density of clams so that a sustainable highyield harvest could be maintained with a combination of naturalrecruitment and stock enhancement using recruits or “seed.” Wereport here on the 30-year experience of the LSSG.

METHODS

We conducted an exploratory survey and a quantitative ben-thic survey of the intertidal portion of the property in 1977. Since

∗Venerupis philippinarum has been variously placed in the genera Venus,Tapes, Ruditapes, and Paphia. It was placed in Venerupis Lamarck, 1818, sub-genus Ruditapes Chiamenti, 1900, by Fisher-Piette and Metivier (1971). Theaquaculture industry continues to use the generic name Tapes, but this is clearlyincorrect.

1977, the area of intensive harvest has increased from approxi-mately 2.2 ha to 6.8 ha, and the total managed area is 40 ha.

LSSG staff conducted the initial surveys with volunteer assis-tance. From 1979 until 1983, the surveys were conducted undersupervision by LSSG staff using paid sampling crews. Samplingwas performed two to three times per year, depending on avail-able daylight low tides because Little Skookum Inlet is subjectto a mixed semi-diurnal tidal regime. While sampling has beenperformed at night, it is inefficient. From 1984 to 1995, the man-ager of LSSG used contracted labor to conduct the surveys. Wereassumed control of the sampling program from 1995 to thepresent.

The initial surveys were conducted with 0.1-m2 quadratstaken from 40 stratified random, pre-positioned sampling sta-tions established on a surveyed grid that covered the entire 2.5-ha intertidal area. Quadrats were constructed of 1-in (2.54-cm)PVC pipe. The sampling grid consisted of a reference centerlinestaked and marked at 10-m intervals laid out with a survey laserbeam and tape measure over the approximately 350 m lengthof the property. Quadrat sample locations were chosen from apredetermined sampling plan for each survey, based on the dis-tribution of substrate type and height on the beach above theMLLW level. The stratification scheme also incorporated inter-tidal zonation as described by Ricketts and Calvin (1968), basedon tidal height of the shellfish beds above the MLLW. Stationssited away from the centerline were located with a 2.5-m right-angle square and a 50-m tape measure.

Samples were taken at each station using a box corer, a rect-angular device constructed of galvanized steel (Figure 1). Thecore encompasses 0.1 m2 and extends to a depth of 15 cm andtherefore contains a sample of 0.015 m3. The corer was droppednear the sample station mark, and a qualitative surface substratetype was recorded. One of the sampling team then stood on thebox corer to press it into the substratum. Trowels were thenused to remove the contents of the corer, which were placed inscreen boxes, one with a mesh size of 12 mm, nested over ascreen of 6-mm mesh. Substrate type at bottom of the core sam-ple was recorded. Sediment on the 12-mm screen was washedand shaken, and all clams retained by the mesh were removed.Materials that had passed onto the 6-mm screen were washedand shaken, and all clams retained by this mesh were removed.All V. philippinarum retained on the mesh were counted andthen each was measured (shell length [SL]) using a “sizingboard” (Figure 1) to the nearest 5 mm. Clams were assignedto corresponding size categories as juvenile (SL ≤ 25 mm), sub-harvestable (25 mm ≤ SL ≤ 40 mm), and harvestable (SL ≥40 mm). Data were recorded in the field, and then the clamswere returned to the hole after the corer was removed. Sampleswere initially removed from the beds to a remote location andscreened at 12 mm, 6 mm, and 3 mm, but screening to 3 mmwas too time consuming for repeated surveys, so screen sizeswere limited to 6 mm and 12 mm after the first three surveys.Clam measurements were made initially using vernier calipers,but measuring with the calipers took too long so we modifiedour procedure to using the calibrated sizing boards instead.

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Figure 1 Field sampling equipment. Clockwise from top: bucket used for wash water and seat for scribe, 6- and 12-mm screens, sizing board with trowel,0.1-m2galvanized steel box corer.

Field data sheets were examined after each survey. Datawere then entered into a spreadsheet and analyzed. Densityof V. philippinarum and other bivalves was calculated perunit area and for the entire farm. Data have been comparedgraphically since 1995 with those from previous years. Thedata were retained in a database for future comparison andanalysis.

In addition to counting and measuring all V. philippinarum,we identified and counted, but did not measure, other bivalvespecies collected during the surveys. An estimate of V. philip-pinarum biomass (relationship of wet weight to shell length,SL) was generated from a random sample of clams in the farmarea following the initial survey in 1977. The biomass estimatewas revised in the late 1980s because of a change in age andsize structure of the farmed population, caused by continuousharvest of clams above 45 mm, and has been regularly examinedduring the clam surveys. The survey data afforded an estimateof total commercial biomass and standing biomass per m2 foreach commercial bivalve species. In addition, we determinedthe population size structure of each species and, from thesedata, estimated age structure. Following estimates of densityand biomass in 1979 (in the third year of operation), juvenile6–8 mm SL V. philippinarum (seed), obtained from commercialshellfish hatcheries, were broadcast onto the clam bed to pro-duce an estimated biomass of approximately 30 kg/m2. Seedingrates on the intensively harvested portion of the clam farm havebeen managed to achieve a clam density of 800 per m2, althoughrecent experiments using 1,600 and even 3,200 seed per m2 havealso been evaluated.

RESULTS

Venerupis philippinarum is the most abundant infaunal bi-valve on the LSSG managed area. V. philippinarum was initiallyfound at a density of 800–1,200 clams per m2 and occurred inthree size (age) classes: recent recruits, 1-year-old clams, and2+-year-old clams. Native littleneck clam Protothaca stamineaoccurred at a lower density, as did Washington butter clam(Saxidomus gigantea) and bent-nosed clam (Macoma nasuta).These bivalves generally occur in the lower intertidal and thuswere a component of the lower elevation of the clam farm. Alsopresent were Olympia oysters (Ostrea conchaphila) and mus-sels (Mytilus trossulus). Economic analyses determined that V.philippinarum had the most potential for return on investmentbased on density, growth rate (time to harvest), and docksidevalue.

Biomass estimates for V. philippinarum were initially calcu-lated to be:

Wet weight = 0.00026 × SL2.9

Subsequent refinement of this relationship following additionalsampling revised the relationship to:

Wet weight = 0.00018 × SL2.4

Venerupis philippinarum density in LSSG beds, determinedby surveys, has fluctuated from 500 to ≥2 000 clams per m2 since1979 (Figure 2). Harvest rates for three years before the forma-tion of the LSSG were approximately 17,000 kg/ha/y, achieved

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Figure 2 Relationship between seeding history and population density for three sizes of clams on Little Skookum Shellfish Growers tidelands. Seeding startsat the bold arrow (Nov, 1979) and increases to a steady 2 × 106 seed per year (800/m2) spread evenly over the 2.2 ha from 1982 until 1987. After 1994, seedingrates increased steadily to 3200/m2 (with the exception of 2001), and sustained harvest has risen proportionally. Intense harvests in 2003 and 2004 anticipated theincreased seeding to follow. No data is available for the time between the two sets of vertical lines (fine arrows) as surveys were not conducted in those 9 month(1987) and 1 year (1990) intervals.

a mean of 40,000 kg/ha/y during the first 3 y of operation, and38,000 kg/ha/y from 1979 through 1985. Landings have fluc-tuated somewhat interannually but have been maintained at aconsistently high level for 30 years, particularly over the past 12years (Figure 3).

DISCUSSION

The economic analysis following the initial evaluation sur-vey indicated that culture of the Manila clam posed the bestpotential for return on investment based on their natural abun-dance, apparent age-structure, and projected rapid growth rate,relative to either Pacific oysters or native oysters. The returnratio per m2/y, at the market price for 2-year-old Manila clamsof US$1.01/kg, was $7.63 m2/y (1977 dollars), compared to thenext highest value crop, 3- to 4-year-old Pacific oysters, whichwere valued at US$2.63/kg or $0.75 m2/y. Based on those har-vest data, we established a management plan that would allowa sustainable, economically viable harvest of V. philippinarum.The proposed plan for managing the clam farm was presentedat a meeting of the National Shellfisheries Association (Glocket al., 1978). The management plan included a permanent sam-pling grid, aerial photography to map bed changes, and multipleannual sampling for biomass using our initial estimated length-

weight relationship. We also proposed to track the age structureof V. philippinarum from length analysis, the presence of otherbivalve species, and a qualitative monitoring of substrate typeand changes. A strict harvest limit, based on estimates of annualsustainable harvest from measured standing biomass and ageclass density structures, was also proposed. The managementplan also anticipated continued surveys at regular intervals toalert us to declines in commercial species biomass per unit areaor to a catastrophic loss, as well as to provide indemnificationagainst accidental catastrophic loss such as from oil or chemicalspills from nearby waters or highways. Tracking abundance ofthe other bivalve species was considered necessary as an indi-cator of general health of the beds.

Conrad (1985) provided details on all advances made in theearly years of LSSG. This model has been successful for threedecades at LSSG and is very similar to what aquaculture spe-cialists worldwide have recently been promoting as the model ofthe future (Pellizzato and Da Ros, 2005; Vincenzi et al., 2006;Zhang and Yan, 2006).

Infaunal clams essentially require grow-out in sediment tomaximize growth and minimize mortality (de Valence and Peyre,1990; Spencer et al., 1991). The benefit of this phase is that theclam farmer need not feed the clams during the grow-out phase,but the clams are also subjected to predation, possible harmfulalgal blooms, or third party accidents such as spills, and they

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Figure 3 Annual harvest of Venerupis philippinarum (kg/ha/y) from the 2.2 hectare Little Skookum Shellfish Growers clam farm from 1992 to 2003.

must be harvested after the grow-out phase (Paterson and Nell,1997; Prioli, 2004; Melia and Gatto, 2005). All of these fac-tors have been carefully considered in the LSSG model. Oneof the most potentially troubling aspects of farming the inter-tidal zone is the connection of the clam farm to the economy.While land-based farms have been successfully integrated intobusiness aspects such as loans, real estate and asset valuation,and insurance (Saama et al., 1994; Alvarez and Nuthall, 2006),the aquaculture industry is still young and not consistently wellintegrated (Ling et al., 1999; Prioli, 2004; Engle et al., 2005).As a result, LSSG has developed, as part of the bioeconomicmodel, a system of surveying that maintained an arms-lengthrelationship between the crews doing the sampling, the con-sultant doing the analysis, and farm management. In addition,surveying provided a method of estimating clam densities andpotential harvest yields and led to the practice of enhancing clambeds with hatchery-produced seed.

The initial LSSG management plan anticipated regular nat-ural recruitment of Manila clams based on the age structureobserved in the surveys, anecdotal evidence, and historical har-vest records. Subsequent monitoring indicated that successfulrecruitment of V. philippinarum from observed spawning in thebeds was less frequent than anticipated. During late 1979, lack-ing observations of significant recruitment in early 1979 surveys,we decided to examine whether enhancement of natural recruit-ment with hatchery-produced seed from local broodstock wouldmaintain natural densities on the beds and help in managing sus-tainable production without changing population diversity andage-structure on the beds. We supplemented the natural set withhatchery-produced seed large enough to ensure a high survivalrate. The first commercial Manila clam seed was obtained fromInternational Shellfish Enterprises of Moss Landing, CA, was

planted in Little Skookum Inlet in November 1979, and con-sisted of approximately 100,000clams of SL 2–25 mm. A privatecontractor subsequently determined that production of 6–8 mmSL seed was feasible for enhancement on the clam beds. Whenwe began in 1979 to examine enhancing the local recruitmentwith commercially produced seed, no hatchery was producingthe numbers required for the seeding program. LSSG contractedwith Ted Kuiper of Arcata, CA, to produce 2 million 6–8 mmSL seed annually. As the area being farmed by LSSG has grown,the volume of seed purchased has grown concomitantly from 2million to a mean of 80 million annually. This increased seedinglevel is carefully monitored through the annual surveys, and har-vest levels have been increased accordingly following a one-yearinterval to allow juveniles to grow into sub-harvestable clams.Seeding was constant between 1980 and 1987, somewhat erraticbetween 1988 and 1994, and was intensified from 1998 to 2005.The results of enhancing the natural recruitment are revealedin increased and consistent harvests from the LSSG (Figure 3).Although anecdotal, the increase in recruit density has had noobservable effect on either biodiversity or substrate structure inthe farmed beds.

The majority of seed planted on our beds to the presentcome from Kuiper Mariculture; however, after 1986, com-mercial Manila clam seed was also planted from the LummiTribal Hatchery, Lummi Island, WA, and after 1993 from CoastOyster Company, Quilcene, WA, and Taylor Shellfish Hatchery,Brinnon, WA. Broodstock for all seed for the first 10 years washand selected from our beds in Little Skookum Inlet. After thatperiod, concerns about inbreeding were raised by both the author(Becker) and outside consultants, and alternative seed sourceswith potentially different broodstock were sought to avoid in-breeding problems. Consultation with Dr. Anya Robinson at

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Oregon State University Marine Laboratory had previously as-sured us that the broodstock we were supplying to Whisky CreekHatchery in Tillamook, OR, the source of Manila clam larvaeto Kuiper Mariculture at the time, seemed to still be robust andshowed no inbreeding difficulty. Since 1995, we have sourcedour seed from as many different broodstocks as possible. A selec-tive broodstock program for Manila Clams, like the existing one,for Pacific oysters (Crassostrea sp.) is projected to begin in 2007.

Future plans are to continue to survey and enhance the densityof V. philippinarum in the intensive harvest area to maintain pre-dictable and profitable harvests. Survey data are currently usedto establish seeding levels and harvest rates through comparisonwith past years and experience-driven estimates of projected for-ward survival from climate observations and beach conditions.The implementation of a GIS-based system to more accuratelytrack clam densities through time and space on the clam bedswill allow more precise manipulation of densities and yields andshould improve on the experience-driven estimates. Recent ap-plication of this and other technologies on bivalve aquacultureoperations in other parts of the world suggest that bivalve cultureis on the verge of becoming much more sophisticated (Melia andGatto, 2005; Vincenzi et al., 2006; Zhang and Yan, 2006).

In addition, we plan to implement in 2007 cooperative re-search experiments with acoustic sub-bottom sediment profilersand neural network analysis of the acoustic backscatter signal toquantify infaunal mollusk populations and characterize the ben-thic habitat, much as Kendall et al. (2005) and Smith et al. (2006)have done. Since we have essentially “calibrated” our beds forclam populations, age/size structures, and biomass density withour precision benthic surveys, immediately after the surveys wecan provide a test area for acoustic sub-bottom survey tech-nology and use that data to ground truth the acoustic systemsfor other similar areas. With enough data, we may be able tocreate exportable systems to survey similar natural areas andpopulations.

Our next goal is to institute some of the principles of “preci-sion agriculture” as practiced in the farming industry to Manilaclam and Pacific oyster farming. Through these techniques wehope to decrease the footprint of shellfish farming by movingfrom extensive aquaculture practices to intensive aquaculture,and to fallowing areas less appropriate to culture while maintain-ing required food supply in more appropriate areas. This man-agement approach seeks to minimize environmental impacts andmaximize food production and maintenance of water quality.

The survey technology LSSG instituted allows demonstrabletracking of Manila clam size frequency and biomass on our beds.In addition, the practice of supplementation with hatchery seedat recruitment size allows manipulation of the size frequency dis-tribution to maintain a given biomass. Thus, surveys combinedwith supplemental seeding present sea ranchers and managerswith a powerful tool to manage populations of infaunal mollusks.

The goal of surveying LSSG’s clam beds is to establish morerational approaches to management with advanced graphicalanalysis of density distribution of biomass and age structure.This should complement the experience-driven system currently

in use and make the technology more transferable and quantifi-able. It will also allow hind casting and modeling of popula-tion dynamics with improved environmental monitoring fromthe weather and the water quality monitoring station we haveestablished in Little Skookum Inlet. Parameters measured in-clude rainfall, air and water temperature, salinity profile andtidal height, and duration.

LSSG seeks to maximize production on the area we farmwhile minimizing the environmental effects, or footprint, of ourfarming. To do this, we began with extensive biological and en-vironmental surveys of the area we were to farm and have con-tinued to the present as discussed under the sections on surveys,seeding, and harvesting. These practices are at the core of thevery high sustainable production we realize from the 6.8 ha wecurrently intensively harvest out of the 40 ha we manage. Thisincludes the 2.19 ha discussed here that produce about 40% ofthe harvest. Total production of V. philippinarum from the above6.8 ha currently averages over 450,000 kg/y, and there is an addi-tional and significant production of Pacific oysters and Olympiaoysters of at least 25% more biomass from the same area.

Maintaining the described level of production for 30 yearscould not be accomplished without significant cooperation fromadjacent landowners, the consultants who help monitor the envi-ronmental and biomass aspects of the production, and the work-ers who cultivate and harvest the shellfish we farm. At the outset,we consulted nearby landowners, local, state and federal gov-ernment, as well as our own workers, so that we maximized oureffort and were never in an adversarial position.

We are required by state statute to harvest our shellfish byhand. However, the profession of hand clam harvesting neededto go from part-time or temporary employment to full-time em-ployment, capable of supporting a family, for LSSG to accom-plish its goal of sustainable high yields. A successful agriculturebusiness model from the grain farming industry was adopted,where approximately one-third of the revenue from the opera-tion of the farm went into salary and benefits to the harvesters andother workers. The remaining two-thirds were divided betweenthe landowner (where it was different from the farm manage-ment) and the farm business entity and profits. At the outset,workers were included in state-supported industrial insuranceplans, and, more recently, the private farm paid full medical in-surance on each employee. Retirement, paid vacation, and otherworker benefit plans have been instituted, and we recently addedEnglish-as-a-second-language programs for both laborers andstaff. Middle- and upper-level management work directly withthe harvesters and must have prior harvesting experience. Thissystem has evolved steadily, and its increasing worker benefitsprogram ensures a steady and reliable supply of labor and en-ables continued high productivity.

To maintain continuity of management, adherence to a suc-cessful business philosophy, seeding, and a rigorous monitoringprogram over such a long period has been challenging. From1978 through 1987, following the initial start up period and com-mencement of Manila clam seeding, the initial business plan,management philosophy, seeding system, and survey program

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led to sustained growth and productivity, as has been demon-strated. Between 1988 and 1994, departures from the previouslyinstituted and successful business plan led to decreased produc-tion and productivity. However, in 1995 we returned to the pri-mary management philosophy, seeding system, and survey pro-tocols, and reestablished increased production of the operation.

CONCLUSIONS

This paper describes only briefly the process that has ledto three decades of sustained high yields, good stewardship ofthe local environment, and socioeconomic benefits to the localworkforce, community, and the clam farm. The following arewhat we define as the keys to the success of LSSG:

1. Obtaining cooperation from many groups to be impacted bychanges in the environment and community and satisfyingall legal requirements before changes are implemented, i.e.,give stakeholders an opportunity for ownership of ideas andconcepts.

2. Detailed surveying of the ecology of the environmental sys-tem to be entered and explicit knowledge of the existing biota,its biomass, diversity, and distribution is a key to successfulsupplementation and enhancement and must be researchedbefore making proposed changes.

3. Biological time constants are long, and it may take 5–10 yearsof surveying after a 2-5 year pre-change baseline study toensure that changes made in an ecosystem are sustainable.Both stock enhancement and sea ranching appear to requirethis level of diligence.

ACKNOWLEDGEMENTS

Many people participated in the time series of surveys thatsupport our conclusions on the sustainability of LSSG and itsproduction system. The authors would like to thank the key peo-ple who have helped keep the process going and contributed ma-terially to the surveys for the last 30 years: Michael Kyte, JamesP Glock, Erik Hurlburt, Daniel P. Cheney, Greg Bonacker, ElaineA. Bishop, Andrew Surbier and the students of The EvergreenState College, The Lakeside School, Seattle, and North MasonHigh School. We also would like to acknowledge the long-timeinterest, advice, encouragement, as well as the thoughtful re-view of this paper from Dr. Kenneth Chew. Finally, the authorsalso wish to thank the anonymous reviewers who contributedsignificantly to the clarity and readability of the paper.

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