Shrimp Research Aboard Soviet Ship in Gulf of Alaska

Shrimp Research Aboard Soviet Ship in Gulf of Alaska

,SHRIMP RESEARCH ABOARD SOVIET SHIP IN GULF OF ALASKA Robert J . Wolotira Jr. One r esult of the 1970 meeting of U.S. and Soviet fishery scientis tsinMos cowwas a joi nt research program to investi­ gate the shrimp resources in the Gulf of Alaska. The Soviet res earch vess e l 'Krill' surveyed offshore areas sout h of the Alaska P eninsula and near Kodiak Isl and from January through March 1971. U.S. scientists were permitted to go aboard and participate in the Soviet part of the research. Fishery scientists from the United States coastline. Because the data gathered during and the Soviet Union have met annually since the Soviet research cruise contained informa­ 1966 to discuss resources of mutual interest tion of considerable interest to U.S. scien­ and the results of their research. During the tists and f ish i n g industry, two biologists Moscow meetinginDecember 1970, they dis­ from the NMFS Kodiak Laboratory- - Perry A. cussed the shrimp species from south of the Thompson Jr. and I --were invited to ac­ Alaska Peninsula near Kodiak Island. In 1970, company the Krill during the remainder of this area yielded a combined U.S. -Soviet the Soviet research operation. The follow­ catch of over 92 million pounds of shrimp. ing photos and text describe our observa­ tions (Figures 1-12). Both countries presented program outlines that had similar objectives: (1) to assess the VESSEL, CREW, AND OPERATIONS standing stock of shrimp offshore along the southeast coast of Kodiak Island and the Alaska Peninsula from Portlock Bank to The Krill was built in the USSR in 1968. Unimak Pass; and (2) to collect biological It is a typical Mayak -class side trawler. data to determine if catches taken both off­ Overall length is 178 ft, beam 30 ft, and draft shore and inshore are from one large homo­ 10 ft; gross displacement is 929 metric tons. geneous shrimp population or from distinct Propulsion is p r ovided by low-speed diesel stocks. Pink shrimp (Pandalus borealis) was engine driving a single variable pitch pro­ the primary species of interest. peller. Cruising speed is approximately 12 knots. Minor modifications for scientific The Research Vessels work inc 1 u de d a hydrographic winch for oceanographic casts, and a wet lab area in Vessels assigned to the research effort the forepeak where samples were processed. were the 'Krill' of the USSR Pacific Scientif­ ic Research Institute of Marine Fisheries Electronic gear on the bridge included and O.::eanography (TINRO), and the NMFS two medium range radars; magnetic and gyro ' Oregon' . The Krill was to sample offshore compasses; radio direction finder; automatic areas during January through March, the pilot; and two multirange, dry paper fatho­ Ore gon adjacent areas during April and May. meters with maximum depth ranges to 600 fathoms. On March 11, Soviet and U .S. scientists met aboard the Krill in Chiniak Bay near The Crew Kodiak, Alaska, to discuss plans for the re­ mainder of the cruise. The Krill had been The Krill's crew numbered 27, including and would continue to operate outside the 12- four women: vessel captain, 3 mates, about m ile contiguous zone bordering the Alaska 8 engineers, 6 fishermen, an electronics Mr . Wolotira is with NMFS Northwest Fisheries Center, 2725 Montlake Boulevard East, Seattle, Washington 98112. MARINE FISHERIES REVIEW Reprint No. 948 45 ~ en o. I I ,­ / , I , , - _.I BRISTOL BAY 5( AoQ r' if tID \ \ \ \..­ ..... ) I / !:-:; t" ..... ",' cS I ,,- ./ ~~. - d;"'i;~f~) " r ~/··i, - 55' U,.., . ~Jl> ;~~~~%J)q:; p "'rr,Ok I / I 0 c:;;,.:::::J Pass <) ~ ..... ./ -, 0 155 0 150 ~ ,0 160 /, '" "., - ~ - I Fig. 1 -Sh aded portion of the chart indicates the area surveyed by the Soviet research vessel Krill during the Joint U . S . -USSR shrimp surveys in the Gulf of Alaska, January­ Ma rch 1971. .. Fig. 2 - Soviet research vessel Krill In ChwlJ.k BJ.Y ""IIt1ng to r nd« ous signifies .. scientific vessel for the Soviet Union's f'aclh I nt.II I tlt,t F19. A 2,OOO-lb ~atch of pink shrimp being dumped on deck. The :t-inch mesh liner inside the cod nd ~an be seen extending past the puckering rings. t bo .. rd, fish and lInertebr te • .ir" separated b~ species, .. nd weight eSll- 49 Fig. 6 - In the vessel laboratory , Chief !>cientist Yuri Skilarof and a technician gather biological data from a shrimp sample. Fig. 7 - Soviet fishermen prepare the net for the next sampling station. The large metal ball in fore­ ground is attached to the center of the headrope. Approximately 40 smaller floats were fastened to the headrope on each side of the large float. 50 Fig . 8 - Large electric winches are used to payout and retrieve the trawl cables. Fig. 9 - Forward portion of the shrimp trawl being brought aboard the RV Krill. Relative size of the net can be detennined by noting the crewman partially obscured by floats at the lower margin of the photo­ graph . 51 Fig . 10 - Perry Thompson (left) of the NMFS Kodiak Laboratory discusses sexual characteristics of Panda.­ lid shrimp with Soviet chief scientist aboard the USSR RV Krill. Fig. 11 - Soviet master fisherman repairing the net. Damage to the fishing gear was commoOlplace while exploring the offshore areas. 52 I Fig. 12 - The RV Knll underway and heading for another sampling station. 53 technician, radioman, cook, and 2 stewards. A systematic sampling pattern started at The women worked as cook, stewardesses, the outer edge of the 12-mile contiguous fish­ and oceanographer. The scientific staff con­ ingzone and extended to about the 120-fathom sisted of a chief scientist (ichthyologist), two contour, with sampling stations every 12 oceanographers, and a fishery technician. miles. At the 120 -fathom contour, the ves­ sel made a 90 0 turn, traveled 12 miles Workdays began at G:00 AM and ended at parallel to shore, made another 90 0 turn back 10:00 PM Alaska S tan dar d Time. The toward shore, and resumed sampling. crew operated in two watches; captain and scientific crew worked the entire 16 -hr At each sampling station, sounding tran­ day. Although the area surveyed was several sects were used to locate trawlable bottom. time zones from home port, clocks aboard Occasionally 2 to 3 hours were spent search­ the vessel always were set to Kamchatka ing before bottom suitable for a 30 -min tow Time, the nearest Soviet time zone across was located. When the net was alongside the Inter national Date Line. vessel at completion of a tow, reversing thermometer-Nansenbottle casts were made. Temperature and water samples were taken GEAR at the surface, and at 25-fathom depth inter­ vals to the ocean floor. Standard fishing gear was a trawl with a liner in the cod end. The trawl had an 89-ft Samples Taken headrope and an overall length (center of headrope to tip of cod end) of 130 ft. An 89- After the catch was taken aboard and ft mud line of cable wrapped with rope (over­ dumped on deck, a sample of approximately all diameter about 5 inches) was attached to 250 shrimp was taken from the center of the the footrope and hung about 12 to 18 inches pile. Then the remainder of the catch was below it. Vertical height at tips of the wings examined and a weight estimate made for was 16 ft, and 20 to 23 ft at the center of the each species. If there were few roundfish, mouth. Eighty floats, approximately 8 inches each individual was counted. in diameter, were attached to the headrope. A subsample of 100 pink shrimp was taken Mesh sizes (stretched measure) in the net fr om the original sample of 250. Each shrimp were: was weighed to 0.1 g on a small balance and measured for total length tothe nearest milli­ Wings and mouth - -5i-inch mesh. meter. Carapace length was measured to the nearest 0.1 mm, and grouped in I-mm in­ Bosom--4-inch mesh. crements for length -frequency analysis. Sex was determined by examination of the endo­ Intermediate and cod end --2 inch mesh. podite of the first pair of pleopods, a method employed by Rasmussen (1953). Sex determi­ Liner in posterior 33 ft of net--i-inch nations were classed into five categories: mesh. juvenile, male, transitional, gravid females, and nongravid females. The trawl was equipped with 137 -ft dandy­ line sand 6 x 9 -ft oval doors. After all samples were taken, the remain­ der of the catch of shrimp and edible fish was Oceanographic data, including salinity and frozen. Fish were eviserated before freez­ temperature measurements, were obtained ing. by a surface thermometer, reversing ther­ mometers, and Nansen bottles. Pink shrimp was the predominant species. Other shrimp and fish species most frequent­ ly captured included sidestripe shrimp METHODS (Pandalopsis dispar), pollock (Theragra c hal cog ram m us), Pacific Ocean perch The sampling techniques were those de­ (Sebastes alutus), and Pacific cod (Gadus veloped during previous Soviet shrimp work. macrocephalus) . 54 SHRL\IP DAT A GATHE RED BY Length- freque ncy (c arapace length) and U.S. SCIENTISTS s ex composition data were obtained by us from s amples at 11 stations--one at Alba­ \Vhile aboard the Krill, we obt ained s am­ tross Bank, 10 fr om a dja cent Portlock Bank-­ pIes from trawl c atches and used a method between M arch 12 and 22. Sex was classi­ developed by Allen (1 959) t o determine the fied into fou r c ategor ies: male, transitional, sex of pink shrimp.

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