Seafood Toxins - ACS Publications - American Chemical Society

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Alaska's Shellfish Industry 1

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RICHARD A. NEVÉ and PAUL B. REICHARDT 1

Alaska Department of Environmental Conservation, Juneau, AK 99811 Department of Chemistry, University of Alaska, Fairbanks, AK 99701

Downloaded by UNIV LAVAL on July 11, 2016 | http://pubs.acs.org Publication Date: September 19, 1984 | doi: 10.1021/bk-1984-0262.ch005

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This is a recounting of the history and a discussion of the potential of the Alaskan shellfish industry. Among the issues addressed are the varieties of clams available for commercial cultivation, the current locale and relative productivity of commercial clam banks, the current efforts at extending commercial harvesting and the contingent technological innovations, the deleterious effect upon the industry by paralytic shellfish poisoning (PSP), and the recent methods of monitoring for PSP. The article concludes with a citing of the difficulties this emerging renewable resource industry is facing. A l o n g A l a s k a ' s 33,000 m i l e s o f a v a i l a b l e a n d r e l a t i v e l y u n p o l l u t e d s h o r e l i n e - e x c e e d i n g t h e c o a s t l i n e o f a l l o t h e r s t a t e s comb i n e d - a r e f o u n d many h a b i t a t s e s p e c i a l l y s u i t a b l e t o a c o m m e r c i a l clam f i s h e r y . From t h e B e r i n g Sea P e n i n s u l a i n t h e n o r t h , along t h e s o u t h c e n t r a l Alaskan coast and throughout t h e southeast p o r t i o n o f t h e s t a t e a r e found s e v e r a l species o f clams o f s u f f i c i e n t s i z e and abundance t o m e r i t commercial m a r k e t i n g . I t i s perhaps the l a r g e s t , untapped f i s h e r i e s resource i n the United States. Along t h e Bering Sea Peninsula alone, i thas been e s t i m a t e d t h a t a n a n n u a l h a r v e s t o f w h o l e c l a m s c o u l d y i e l d 19 t o 25 m i l l i o n p o u n d s o f m e a t . More c o n s e r v a t i v e e s t i m a t e s p l a c e t h e true sustainable harvest f o rthe e n t i r e state i n the neighborhood o f 50 m i l l i o n p o u n d s p e r y e a r i n c l u d i n g s h e l l w e i g h t . In either c a s e , t h i s r e p r e s e n t s c o n s i d e r a b l e u n d e r u t i l i z a t i o n o f a renewable resource (1). Of t h e o v e r one h u n d r e d s p e c i e s o f c l a m s f o u n d i n A l a s k a ' s w a t e r s , t h e r a z o r clam, S i l i g u a p a t u l a , i s g e n e r a l l y t h e most p r i z e d and has a very great commercial p o t e n t i a l . This clam i s f o u n d i n a b u n d a n c e o n many A l a s k a n b e a c h e s , a n d i n t h e p a s t h a s been s u c c e s s f u l l y marketed; however, due t o t h e u n p r e d i c t a b l e p r e s e n c e o f P S P , i t s d u a l u s e now i s a s a b a i t f o r d u n g e n e s s crab, and a r e l a t i v e l y s m a l l consumable commercial market. At the present time, there a r e only three approved beaches f r o m w h i c h r a z o r c l a m s may b e h a r v e s t e d f o r c o m m e r c i a l p u r p o s e s . These a r e Swikshak, P o l l y Creek, and t h e Cordova area. I t i s estimated t h a t these three beaches alone represent a p o t e n t i a l annual h a r v e s t o f one m i l l i o n pounds ( s h e l l weight) and a m i n i mum o f t w o m i l l i o n d o l l a r s o n t h e w h o l e s a l e market. H i s t o r i c a l l y , t h e r a z o r clam has been A l a s k a ' s one r e a l clam f i s h e r y . Commercial h a r v e s t o f r a z o r clams i n Cook I n l e t began i n 1919 w i t h p r o c e s s i n g t a k i n g p l a c e a t Snug H a r b o r o n t h e

0097-6156/ 84/ 0262-0053$06.00/ 0 © 1984 American Chemical Society

Ragelis; Seafood Toxins ACS Symposium Series; American Chemical Society: Washington, DC, 1984.


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SEAFOOD TOXINS

west side. Very l i t t l e data i s available p r i o r to 1945 other than noting that Polly Creek was the main harvest area. Razor clams are found up to Cape K a s i l o f on the east side and to the Kustatan River on the west side. From 1945 to 1949, production was i n s i g n i f i c a n t , averaging less than 10,000 pounds annually. For 1950 and 1951, production increased to 304,000 and 112,000 pounds, respectively (_2) . There was no production at a l l from 1952 through 1959. In 1954 Alaska was expelled from the National S h e l l f i s h Council, the national regulatory body for s h e l l f i s h , which meant clams could no longer be shipped out of state for human consumption. Operations (2) began again i n 1960, with commercial harvesting being limited to the Polly Creek area. The fishery continued at Polly Creek through 1963 with the harvest declining from approximately 372,000 pounds i n 1960 down to 195,000 pounds in 1962. From 1963 through 1970, no commercial harvest occurred. The annual harvest averaged less than 30,000 pounds from 1971 through 1973, at which time, the State was readmitted to the National S h e l l f i s h Sanitation Program. The Cook Inlet razor clam harvest from 1919 to the present came from Polly Creek exclus i v e l y . The extreme fluctuations i n harvest throughout the history of t h i s fishery are attributed more to fluctuations i n e f f o r t and market conditions than to the abundance of clams. The 1981 razor clam fishery i n Upper Cook Inlet increased substantially i n both harvest and e f f o r t . Early that year the Alaska Department of Environmental Conservation (ADEC), coordinating with the National S h e l l f i s h Council, obtained c e r t i f i c a tion of the Crescent River bar as an extension to the Polly Creek beach. This e f f e c t i v e l y doubled the area available to harvest for human consumption by allowing two processors to operate simultaneously without i n t e r f e r i n g with each other. One processor operated at Polly Creek with 15 to 20 hand-diggers while the other moved into the Crescent River bar area with about 30 individuals hand-digging. Approximately 70 percent of the 1981 harvest, or 315,000 pounds, came from Crescent River bar (2). In 1981, the expanded harvest area and increased e f f o r t combined to y i e l d the highest recorded commercial harvest of razor clams for Upper Cook Inlet since 1922. Over 440,000 pounds of clams in-the-round were harvested from A p r i l through September from the Poly Creek/Crescent River bar area. This equates to roughly one m i l l i o n razor clams. The razor clam fishery i n Cook Inlet has garnered increasing commercial interest i n recent years with the 1982 season r e s u l t i n g i n a noticeable upswing i n requests for information concerning harvesting and processing information; 1983 information i s not yet available. Applications for provisional permits to operate hydraulic clam dredges have been received. On-site inspection of these dredges p r i o r to harvesting i s prescribed i n the permit. One of the more notable operations seeking a provisional permit i s a vessel-mounted subtidal razor clam dredge capable of harvesting clams i n depths up to ten fathoms. This enterprise i n i t i a l l y targeted the b a i t clam area but w i l l s h i f t to the human consumption area ( i . e . , Polly Creek) i f and when b a i t contracts are f i l l e d .



5.

NEV£ AND REICHARDT

Alaska's Shellfish Industry

Presently, the Alaska Department of Fish and Game (ADF&G), (Commercial Fisheries D i v i s i o n , Soldotna o f f i c e ) , carries out biweekly sampling for PSP and water quality as set forth i n the Interagency Memorandum of Agreement. These sampling t r i p s take place A p r i l through September and are the extent of the department's monitoring and data c o l l e c t i o n a c t i v i t i e s directed at razor clams i n Cook Inlet. A monitoring program directed at gathering information on age structure, density, set frequency and other basic b i o l o g i c a l parameters i s being considered, but budgetary constraints leave the i n i t i a t i o n of such a program i n doubt. While i t sounds l i k e t h i s i s a S i l i q u a patula soliloquy, other species have potential also. There has been a new interest (starting i n 1977) i n the commercial u t i l i z a t i o n of geoducks (Panope generosa). Geoducks of acceptable commercial size are approximately 30 years of age, with some old-timers running over 100 years (_3) . A limited exploratory cruise was conducted i n 1980-81 i n the Ketchikan area, and samples were taken to determine levels of PSP. The results of that cruise were s u f f i c i e n t l y encouraging that additional funds were sought to do a more in-depth study. The goal was to establish commercial harvest techniques and to determine areas where commercial quantities of geoducks could be found. This would allow the new industry to be established, s t i l l protect the consuming public from any possible PSP contamination, and delineate areas of commercial concentration. The beds surveyed were chosen as a r e s u l t of previous knowledge and t i p s from fishermen, or favorable-looking bottom conditions. The second part of the study involved test marketing. Samples were market tested after undergoing various levels of processing. Some were shipped l i v e ; some were eviscerated; and others were butchered and shipped separately as necks or bodies. Different grades were also shipped to test the marketability of the lower quality geoducks. Market samples were sent to Japan, Los Angeles, New York, Seattle, Santa Barbara, San Francisco, San Diego, and Korea. A l l products were acceptable to the markets tested. Prices ranged i n 1982 from $.70 per pound to $3 per pound, depending on quality and the degree of processing (3_) - I t i s anticipated that, i n the future, l o c a l processors could buy d i r e c t l y from the fishermen and develop wholesale markets from t h e i r plants. Samples were also taken from the geoduck beds for PSP analysis (_3) . Spot check samples were taken, with results indicating that high l e v e l s existed only i n the viscera of the clam. Of a l l samples taken, only one sample of body meat taken near Gravina Island (Ketchikan, 1980) revealed PSP levels above the quarantine l i m i t of 80 mg/100 g for human consumption. Additional studies were taken to investigate clam abundance and d i s t r i b u t i o n of potential harvest areas and to test for PSP homogeneity i n geoduck beds to determine probable methods f o r product control. (At the same time samples of butter and horse clams were also collected for PSP testing.) Indications are that numerous commercial beds of geoducks



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are available, and that a viable industry could begin throughout the lower half of southeast Alaska. In fact, t h i s summer ADEC has received from the U.S. Food and Drug Administration (FDA), market clearance f o r human consumption of geoducks from beds near Noyes Island, west of Ketchikan. Other areas w i l l l i k e l y open up next season. Butter clams, (Saxidomus gigantea), found throughout southcentral and southeast Alaska, were commercially fished u n t i l the presence of PSP destroyed the industry. There are no plans f o r immediate u t i l i z a t i o n of t h i s clam commercially because of the high PSP content of the meat, and lack of a rapid and suitable depuration procedure. Although not commercially harvested i n the past, the steamer clam, Protothaca staminea, i s also available on some beaches i n commercial quantities. At the present time, steamers are imported from outside the state as a luxury item. Results (4) of a 1976-1977 clam survey (by National Marine Fisheries Services, FDA, the University of Alaska, ADF&G, and ADEC) indicate a potential commercial market f o r the surf clam (Spisula polynema). The beds, found along the Alaskan Peninsula between Port Moller and Port Heiden, can be harvested using an east coast-style hydraulic clam harvester which operated effect i v e l y i n the Bering Sea substrates. A surf clam resource area extends over 1600 square miles at a depth i d e n t i f i e d between 13 to 18 fathoms. While detailed production f i s h i n g tests were not conducted, catch rates obtained with the three-foot wide harvester indicate commercial p o t e n t i a l with a ten-foot wide harvester. The resource biomass has been conservatively calculated at 248,000 to 324,000 metric tons of whole clams, with an annual p o t e n t i a l y i e l d of about 19 to 25 m i l l i o n pounds of meat. The average size of Alaskan surf clams was found to be smaller than the East Coast species; however, the meat y i e l d was considerably higher. Tests have indicated that surf clams can be held l i v e aboard ship, either tanked or dry, without excessive dead loss. B a c t e r i o l o g i c a l tests indicate that clams and the environment meet FDA requirements. No PSP toxins were detected i n the edible portion of surf clams using the mouse bioassay. In 1917 the industry produced f i v e m i l l i o n pounds of s h e l l f i s h products (J5) . Today Alaska's commercial clam fishery i s v i r t u a l l y nonexistent. The destruction of t h i s f l e d g l i n g clam industry i n the 1940s was a d i r e c t r e s u l t of product contamination by PSP. Forty years l a t e r we are s t i l l seeking a sol u t i o n ; but, we are beginning to see a l i g h t at the end of the tunnel. I t i s obvious that there i s great p o t e n t i a l f o r a successful commercial clam fishery i n Alaska - i f several problems can be resolved. F i r s t and foremost are the problems associated with PSP, caused by the presence of toxic metabolites produced by d i n o f l a g e l l a t e s of the genus Protogonyaulax (6^) . In addition the Department of Environmental Conservation has recently contracted with two independent laboratories f o r an improved method for monitoring PSP. One i s an immuno chemical method. Another method under study to determine the presence of PSP i s an on-site monitoring system - a black box, i f you w i l l -



5. NEV£ A N D R E I C H A R D T

Alaska's Shellfish Industry

whose operating p r i n c i p l e i s of a proprietary nature. It cannot be revealed u n t i l the patent i s secure. I t i s s u f f i c e to say that ADEC has invested $60,000 i n each study. Additional research i s directed toward a method of neutralizing the toxin. Second, i n addition to the PSP problem, the commercialization of Alaska's s h e l l f i s h industry i s hampered by high labor and transportation costs along with a scarcity of readily a v a i l able c a p i t a l . However, these problems lend themselves to solutions through innovation, mechanization and some forms of low interest state loans. A t h i r d concern i s the industry's a b i l i t y to compete with clam products harvested from the East Coast, Canada, Japan and Korea. To successfully compete, we must e s t a b l i s h a reputation for a safe and wholesome quality product. To t h i s end, Alaska has become a member of the National S h e l l f i s h Sanitation Program which allows us to p a r t i c i p a t e i n interstate marketing. In addition, the state has i n s t i t u t e d a seafood c e r t i f i c a t i o n program. Fourth, technological innovations (such as the use of dredges) to increase harvest y i e l d s and reduce labor costs w i l l be necessary i f a successful commercial industry i s to be established. F i n a l l y , i f Alaska's clam industry i s to grow, i t w i l l be necessary to devote more resources to beach c e r t i f i c a t i o n and monitoring. I f clam b a i t harvesting i s transferred to presently noncertified beaches, i t w i l l serve to a s s i s t i n the i d e n t i f i c a tion of the most productive new clam beaches. At a time when the available resources are decreasing due to p o l l u t i o n and overfishing elsewhere i n the United States, a consumer demand for s h e l l f i s h products has created the conditions for an expanding and p r o f i t a b l e market. Alaska, with i t s r e l a t i v e l y uninhabited and unpolluted shoreline, with i t s many species of commercially harvestable s h e l l f i s h , has a great p o t e n t i a l f o r economic growth, i f a renewed s h e l l f i s h industry can be established. Here i s what we now know about the prevalence of PSP i n Alaskan waters (7_) . We have recently conducted surveys i n southeast Alaska and the Bering Sea - the two regions of most obvious economic potential - on the presence of PSP-producing dinoflagellates. Our method consisted p r i n c i p a l l y of incubating sediment from s h e l l f i s h beds and observing the growth of Protogonyaulax. In many cases we subsequently grew cultures of clonal i s o l a t e s and demonstrated t h e i r t o x i c i t i e s . In southeast Alaska we extensively surveyed the Icy S t r a i t s cross sound areas and - to a lesser extent - the Ketchikan area. B a s i c a l l y we found toxic d i n o f l a g e l l a t e s everywhere we looked. Although quantitative results were not as clear cut as we may have hoped, i t appears that toxic d i n o f l a g e l l a t e cysts are widespread and tend to concentrate i n the fine sediment found i n "holes" or "pockets" i n the ocean bottom. Unfortunately, t h i s appears to be the case even i n the v i c i n i t y of supposedly "safe" beaches where s h e l l f i s h seem to be protected only by serendipitous hydrology and/or environmental conditions. Thus the


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prognosis for commercial s h e l l f i s h development i s not good i n southeast Alaska. Things, however, appear to be quite different i n the Bering Sea. The f i r s t thing we discovered i s that t h i s area i s an expensive and d i f f i c u l t one to sample. The limited sediment samples collected near shore in the Port Moller/Port Heiden study area consisted mostly of coarse materials which contained few, i f any, viable dinoflagellate cysts. Sediments which could be cultured to produce toxic dinoflagellates were, however, found i n areas having h i s t o r i c a l and recent PSP episodes - e.g. Lost Harbor and Dutch Harbor. In addition, a near uniculture of a toxic Protogonyaulax species was found i n waters over the Middle Shelf in the Spring of 1981 (8). While PSP-producing organisms are present i n t h i s area, they appear to be less widespread than in southeast Alaskan waters, a finding consistent with the commercial s h e l l f i s h survey findings in the late 70's. Although the potential for PSP problems i n these centers c l e a r l y e x i s t s , i t seems that - unlike southeast Alaska - PSP w i l l not preclude commercial exploitation of the Bering Sea s h e l l f i s h resource.

Literature Cited 1. Feder, H.M.; Paul, A.J. Alaska Seas and Coasts 1974, 2, 1-7. 2. Reusch, P.; Browning, J. "Upper Cook Inlet Razor Clam Report"; Alaska Department of Fish and Game, Division of Commercial Fisheries, 1982; pp 1-6. 3. Blankenbeckler, D.; Koeneman, T.; Gunstrom, G. "A Research and Management Approach to an Exploratory Fishery on Geoducks in S.E. Alaska"; Alaska Department of Fish and Game, Division Commercial Fisheries, 1982; pp 1-15. 4. Hughes, S.E. "Abundance, Quality and Production Fishing Studies on the Surf Clam, Spisula polynyma, in the S.E. Bering Sea", 1978, NW Alaska Fisheries Center Report. 5. Orth, F.L.; Smeller, C.; Feder, H.M; Williams, J. "Alaska Clam Fishery: A Survey and Analysis of Economic Potential"; Alaska Sea Grant Report 75-5, 1975; pp 1-148. 6. Hall, S.; Reichardt, P.B.; Neve', R.A. Biochem. Biophys. Res. Commun. 1980, 97, 649. 7. Hall, S. Ph.D. Thesis, University of Alaska, 1982. 8. Sambrotto, R. Institute of Marine Science, University of Alaska, personal communication, 1981. RECEIVED May 21, 1984


Seafood Toxins - ACS Publications - American Chemical Society

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