UNIT 20 ALASKA SHELLFISH FISHERIES INTRODUCTION Alaska shellfish catches generated ex-vessel revenues of about $318.7 million in 1992. King and Tanner crab fisheries are currently the most important shellfish fisheries at $305 million. Shrimp resources contributed only about $687,000; their present abundance is too low for significant commercial utilization at this time. There is a fairly large sea snail resource waiting to be utilized that may add a few million dollars to the revenue total. Alaska also harvests the following invertebrate resources, mostly within State waters: Dungeness crab, Korean horsehair crab, sea cucumbers, sea urchins, scallop, abalone, geoduck clam, and octopus. The ex-vessel revenue received for these landings (4,340 t) was $13 million in 1992. The first major domestic king crab fishery off Alaska began in the 1960's off Kodiak Island, later expanding to the Aleutian Islands and Bering Sea. The king and Tanner crab fisheries are managed primarily by the State of Alaska with advice from a Federal FMP for the Bering Sea and Aleutian Island stocks. The snail fishery is managed by a Federal Preliminary Fishery Management Plan (PFMP). Shrimp fisheries and the nearshore rsources are managed by the State of Alaska. SPECIES AND STATUS Crab Three species of king crabs (red, blue, and golden or brown) and two species of Tanner crabs (Chionoecetes bairdi and C. opilio) are harvested commercially off Alaska. Values for RAY, CPY, and LTPY are presented in Table 20-1. Information on CPY and LTPY is lacking for king and Tanner crabs; thus default values were derived from historical average catches. Alaska crabs are all fully utilized. The RAY of king crabs during 1989-91 of 12,710 t has been below the LTPY of 27,070 t. By contrast, RAY for Tanner crabs of 112,510 t during 1989-91 has been above LTPY of 40,900 t. The annual dockside revenue for Alaska king crabs (about 12,000 t) and Tanner crabs (about 157,470 t) in 1992 was $305 million; 26% ($79 million) was attributable to king crabs and the rest to Tanner crabs. Almost all (99%) of the Tanner crab production came from the Bering Sea, where C. opilio comprised 54% of the value. Virtually all king crab landings came from the Bering Sea/Aleutian Islands (BSAI). Red king crab made up 66% and brown king crab contributed 23% of the landed value. About 350 vessels make up the BSAI crab fleet. Over 400 vessels harvest crabs in the Gulf of Alaska, although there was considerable vessel overlap between the areas. Catches are restricted by quotas, seasons, and size and sex limits. Fishing seasons are set at times which avoid molting, mating, and softshell periods, both to protect crab resources and to improve product quality. Only male crabs are permitted to be harvested. Catch and abundance trends for king crabs are shown in Fig. 20-1. After a 1964-66 peak, declines were evident. Until 1967, Japanese and former Soviet Union fisheries dominated Bering Sea landings, but those fisheries were phased out by 1974. In the Bering Sea, domestic catches peaked at 74,000 t in 1980, dropped precipitously in 1981, and hit a low in 1983. Since then, there has been a slight gradual increase in the catch. Gulf catches varied at a relatively low level for a decade before dropping lower yet in 1983. Almost all Gulf of Alaska king crab fisheries have been closed since 1983. Tanner crab catches are largest in the eastern Bering Sea (Fig. 20-2). The 1965-75 period was a developmental phase. During 1975-85, the catch peaked at about 49,000 t in 1979 and then declined. Since 1984, the catch has increased, reaching about 163,500 t in 1991. Abundance trends for the eastern Bering Sea stocks indicate that the C. bairdi stock declined from a relatively high level in the late 1970's to a low in 1985. Since then, the Bering Sea C. bairdi stock has recovered and is currently approaching its former level. From a low in 1985, the C. opilio stock has rebounded sharply and is approaching an all-time high level. The catch in the Gulf of Alaska, composed exclusively of C. bairdi, reached peak levels during the 1970's, following a developmental phase in the late 1960's. Since 1979, the Gulf of Alaska catch has declined. Shrimp and Sea Snail Five species of shrimp contribute substantially to Alaska landings, of which the northern pink shrimp is most important. The U.S. fishery for shrimp in Alaska waters is currently at a low level. The 1992 catch in the Gulf of Alaska was only 900 t, and generated an ex-vessel revenue of about $680,000. Shrimp abundance is too low in the Bering Sea to support a commercial fishery. The western Gulf of Alaska has been the main area of operation. During the 1970's, when the fishery was more productive, 50-100 vessels trawled for shrimp at Kodiak and along the Alaska Peninsula. Shrimp landings in the Gulf of Alaska during 1960-90 (Fig. 20-3) show that catches rose steadily to about 58,000 t in 1976 and then declined precipitously. Since 1988, negligible amounts of shrimp have been landed. During 1960-90, the dockside ex-vessel revenue from the western shrimp fisheries averaged $4 million annually and yielded a peak revenue of $14 million in 1977. Shrimp catches by the former Soviet Union and Japan in the Bering Sea peaked at 32,000 t in 1963, and declined gradually thereafter, until the fishery ended in 1973. As with crabs, the potential yields of Alaska shrimp stocks are not well understood, and they have been equated to recent catches. Shrimp are managed by regulating the catch levels according to the level of the stocks. In addition, spring egg hatch closures are used to protect breeding stocks. The Japanese fishery for snails, conducted from about 1971 until ending in 1987, reached a peak of some 13,000 t in 1974. Catches averaged about 4,800 t during 1971-87. The snail stocks of the Bering Sea are underutilized because they are currently not fished. RAY and CPY equal the 1985-87 average catch and LTPY equals the 1971-87 average. ISSUES Bycatch The bycatch of crabs in trawl and pot fisheries is a major issue. Not only is bycatch an allocation problem, the unknown mortalities associated with trawl and pot gear discards of crabs could have a biological impact on crab stocks. When crab numbers are low, such bycatch mortalities, coupled with directed fishing mortality, could impose unacceptable risks to stock recovery. Bycatch limits for king and Tanner crabs have been placed on groundfish fisheries by the NPFMC.