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PB82-23011 M NOAA Technical Memorandum NMIFS F/NWC-29 Data on Fish Species from Bering Sea and Gulf of Alaska Karl Niggol April 1982 SH 11 U.S. DEPARTMENT OF COMMERCE .A2 National Oceanic and Atmospheric Administration N6 National Marine Fisheries Service no. 29 This TIVI series is used for documentation and timely communication of preliminary results, interim reports, or special purpose information, and have not received complete formal review, editorial control, or detailed editing. This document is available to the public through: National Technical Information Service U.S. Department of Commerce 5285 Port Royal Road Springfield,.VA 22161 0 NWAFC Species Data for Ecosystem Simulation DATA ON FISH SPECIES FROM BERING SEA AND GULF OF ALASKA By Karl Niggol PropertY Of CSC.Library U.S. DEPARTMENT OF COMMERCE NOAA COASTAL SERVICES CENTER 2234 SOUTH HOBSON AVE CHARLESTON, SC 29405-2413 Resource Ecology and Fisheries Management Division Northwest and Alaska Fisheries Center National Marine Fisheries Service National Oceanic and Atmospheric Administration 2725 Montlake Boulevard East Seattle, WA 98112 April 1982 TABLE OF CONTENTS Page 1. Purpose of the data summaries ...................................... 1 2. Sources of data and explanation of terms ............................ 1 3. Methods used to compute derived parameters .......................... 4 4. Explanations to tables and graphs ................................... 5 S. Data on commercial species ......................................... 7 5.1 Walleye Pollock (Theragra chalcogramma) ........................ 7 S.2 Pacific cod (Gadus macrocephalus) .............................. 18 S.3 Sablefish (Anaplopoma fimbria) ................................. 29 5.4 Yellowfin sole (Limanda aspera) ................................ 40 5.5 Greenland turbot (Reinhardtius hippoglossoides) ................ Sl 5.6 Flathead sole (Hippoglossoides elassodon ...................... 62 5.7 Rock sole (Lepidopsetta bilineata) ............................. 73 5.8 Pacific ocean perch (Sebastes alutus) .......................... 84 5.9 Atka mackerel (Pleurogrammus monopterygius) .................... 95 5.10 Pacific herring (CLTea harreng!js pallasi ..................... 106 6. References (data sources) ........................................... 117 1. PURPOSE OF THE DATA SUMMARIES The fisheries ecosystem simulation models require large quantities of fisheries and species specific data as input. These data must be "distilled" and evaluated from a rather large number of published reports, and unpublished data sheets. In the process of this data collection and evaluation, it was found that most of the data were not easily available. Moreover, the quality of data varied considerably, thus requiring considerable analysis and evaluation. Therefore, summarization and consolidation of these data served as the reasons for preparation of this species summary. The data presented here are mean values for two regions--the eastern Bering Sea and Gulf of Alaska. Biometric characteristics of most species indicate that separate stocks exist in these two regions, although in some species considerable migrations and intermixing between these two areas occur. 2. SOURCES OF DATA AND EXPLANATION OF TERMS The basic biometric data (age-length, age-weight, and weight-length) were either extracted from published literature, obtained from colleagues in NWAFC, or extracted from Resource Assessment and Conservation Engineering (RACE) Division survey data files or from Resource Ecology and Fisheries M@nagement (REM Division. The biometric data presented in this summary are long-term mean values for two regions: the eastern Bering Sea and the Gulf of Alaska. Length and weight data are mean values for females and males together, assuming a 50-50 sex composition. -2- A long-term mean age composition of exploitable year classes is required for the computation of biomass and mortality distribution with age. A mean age composition of commercial catches was obtained by adding all available age compositions over a number of years, thus eliminating the effects of strong and weak year classes (Fig. 1A). Furthermore, a "knife edge" recruitment was assumed for the youngest, fully exploited year class (Fig. 1B). The "tail end" of older year classes, which constitute only minor contributions to catches., was neglected (Fig. 1B). This "tail" presents, in many cases, the survivors of strong year classes. The younger limits of the exploitable age length and weight given in the species tables depend on the gear used. Further, the oldest exploited age was determined as in Figure 1, neglecting the "tail end." The domestic and foreign catches refer mostly to 1980 data which were taken from various internal reports in NWAFC. No "official" catch statistics exist for the NE Pacific Ocean, which would be comparable to International Council for the Exploration of the Sea statistics in the North Atlantic. Depth distribution of the species and its seasonal limits were taken from available reports and/or obtained from colleagues. Depth distribution of catches refers to present fishing practices. The depth distribution of species varies seasonally and the depths given refer to present knowledge of depth distribution of exploitable stocks. Age of maturity refers to the age when >50% of the population is mature. The age of maturity is not known for many species. It is known to vary with the growth rate of the species. -3- Exploitable age (length, weight) Lower Higher value value Adjustment in some species Long term mean and areas isum) year classes a) .0 E Possible individual year classes Prefishery A juveniles (not fully recruited) CL 0 2 4 6 8 10 Age (years) E B :3 1 "Knife edge" 0 recruitment 100% "Tail" neglected _J 0 2 4 6 8 10 12 Age (years) Figure l.--Scheme for determination of long-term mean age composition of fully exploited year classes. "ea u @_, 1004 -4- The times of spawning and spawning areas and depths, which vary with -locations, are also not known in detail for many species. The fecundity is a function of size/age of the species and varies somewhat from one region to another. At the end of the "species tables" qualitative notes on the food composition are given. Quantitative estimates of food composition have been given in ecosystem model input documentations. Turnover rates refers to the quotient of total annual mortality of biomass by annual mean biomass (standing stock). Growth rates are given in percent of biomass growth (with reference to the previous months biomass, Bt-1). Condition factor (coefficent) is not computed here. Where it is mentioned in the text, it refers to quotient of weight divided by cube of length. This summary indicates many shortcomings in available data. It especially points out the need to obtain accurate measurements on representative samples (i.e., purposefully stratified samples), rather than careless measurements en masse. The Ecosystem Modeling Task would appreciate all comments, corrections, and additions which the users of this memorandum care to make. 3. NETHODS USED TO COMPUTE DERIVED PARANETERS This data summary contains several derived (computed) quantities, such as biomass distribution with age and age specific total mortality, most of which are necessary for the ecosystem simulation. They have other -5- uses in fisheries problems as well. The methods (and formulas) of computations of these parameters are described by Laevastu and Larkins 1981. The weight at age data are used for computations of growth rates (in weight). The annual individual growth rates are given in graphical form and the monthly growth rates of total biomass, juveniles and adults, are given in the table for given annual turnover rate of the biomass. The distribution of biomass with age for a given turnover rate and the corresponding distribution of total mortality with age (expressed as percent of mortality of the mean biomass at a given age) are given in the graphs. Biomass and mortality distributions also depend on the annual turnover rate. The selected turnover rates are close to those found with Prognostic Bulk Biomass (PROBUB) model, 4. EXPLANATIONS TO TABLES AND QWHS The numerical and graphical data for each species are followed by brief notes on the status of the data and indications of some findings during the preparation of the summaries. The first, general tables for each species gives a variety of estimated data for each of the two regions (eastern Bering Sea and Gulf of Alaska); exploitable age, length, and weight; domestic and foreign catches; depths of distribution and fishin ; age and length at maturity; spawning season 9 and areas; and fecundity. -6- The following values are cQInputed at given turnover rate: percentage of exploitable and juvenile biomasses, monthly growth rates (in percent per month of the biomass present) of whole biomass, and of juvenile, adult, and deceased fractions of this biomass. Finally, qualitative notes on principal food components are listed. 0 The first graph is age-length relation (assuming a 50-50 sex composition), followed with tabular data of the same. The second graph is length-weight relation, followed with a table, and the third is 0 age-weight relation, followed again with a table. The fourth graph is the age composition of the fully exploited year classes (number based), normalized to knife-edge recruitment. 0 The following three graphs are derived (computed) quantities: growth rate in percentage per year of the mean biomass of the year class, distribution of total biomass with age (in percentage of total), and 0 total mortality of individual year classes expressed as percentage of mean biomass of the same year class. Obviously this value can exceed 100% in year classes where the growth rate is above 100%. These two 0 last graphs pertain to a given turnover rate, which is indicated on the graph. 0 -7- 5. DATA OF CO"ERCIAL SPECIES 5.1 WALLEYE POLLOCK (Theragra chalcogramma) Due to variability in data, no interannual changes of growth rate can be observed. There is also considerable uncertainty in the meager data available on age and size at maturity. No essential differences in length and weight at age can be observed between the Gulf of Alaska and the Bering Sea. (That the fish in the Bering Sea might grow slightly faster as juveniles, might be due to greater abundance of euphausiids in this area.) The data do not allow any conclusion of separate stocks occurring in the two areas; some data indicate that there is considerable intermixing of pollock between the Gulf of Alaska and the Bering Sea. (There is an accumulation of older specimens in colder areas in the Bering Sea. The higher total mortality in the Gulf of Alaska of fish 5 to 8 years old might indicate emigration to the north.) The fish in the Bering Sea come under full exploitation one year earlier than the fish in the Gulf of Alaska. The relatively long "tail end" in long-term mean age composition of catches indicates that the stock had not been fished heavily in the past, -8- WALLEYE POLLOCK (Theragra chalcogramma) Gulf of Alaska Bering Sea Exploitable - age (years) 4-11 3-11 length (cm) 35-60 30-60 weight (g) 350-1400 200-1400 Catches - domestic (t) 2/ 1100 10,500 foreign (t) - 110,000 1,006,000 Depth - distribution (m) 3/ 30-2000 50-2000 fishing (m) - 100-200 winter 90-300 50-150 summer Maturity - age (years) 3 3 length (cm) 30 30 Spawning - season March to June March to July area Between Kodiak Isl. and All over E. Bering mainland (Shelikof Strait) Sea (major spawning in SE Bering Sea) Fecundity 29,000 to 169,000 186,000 to 600,000 At a turnover rate of .65 Exploitable biomass,% 63.1 74.8 Juvenile biomass,% 36.9 25.2 Growth rate, % per month Whole population 4.0 4.o Juveniles 7.4 8.6 Adults 2.00 2.5 Deceased 5.2 5.1 Notes on food composition: Most important food items - euphausids, copepods, young pollock, shrimp, crab, other fish, and amphipods. Major year classes exploited 2/ Provisional estimates for 1980 (Murai et al. 1981). 3/ Pelagic over deep water -9- AGE-LENGTH-WEIGHT KEY Pollock (Tberagra chalcogramma) Bering Sea Gulf of Alaska l/ 2/ 3/ Age Length= Weight- Length= Weight cm 9 cm 9 1 15.3 32.0 15.0 28.0 2 25.1 130.0 25.0 118.8 3 32.4 252.0 33.0 223.0 4 38.6 425.0 38.8 399.0 5 43.6 614.8 43.1 581.8 6 47.5 781.3 46.4 737.5 7 50.2 911.6 49 .3 873.8 8 52.7 1035.3 52.0 1002.0 9 54.8 1154.3 54.2 1105.0 10 56.5 1265.2 56.4 1205.0 11 58.4 1380.0 58.1 1320.5 12 59.8 1480.5 59.6 1418.4 13 61.2 1565.0 60.6 1505.5 l/ Smith, 1979; Pereyra et al. 1976; Observer Program. 2/ Smith 1979; Pereyra et al. 1976; Observer Program 3/ Ronholt et al. 1978; M/F cruise 1978/3; Observer Program. 4/ Ronholt et al. 1978; Observer Program; Calculated from age-weight data. _10- LENGTH-WEIGHT KEY Pollock (Theragra chalcogramma) (Calculated from age-length and age-weight data) Bering Sea Gulf of Alaska Length Weight Weight cm 9 9 10 12.5 11.9 20 72.5 60.0 30 200.0 198.5 40 475.0 455.0 50 915.0 905.3 60 1475.0 1520.0 70 1950.0 POLLOCK Age - length 70 - 60 - 50 - 40- -c En c a) -J 30- 20 - Bering Sea 10- Gulf of Alaska 2 4 6 8 10 12 14 Age (years) POLLOCK Age - weight 1600 - 1400 - 1200 - 1000- 800 600- 400- Bering Sea 200 - Gulf of Alaska 2 4 6 8 10 12 14 Age (years) POLLOCK Length - weight 2000 - 1600 - 1200- -c 800- Bering Sea 400- Gulf of Alaska 10 20 30 40 50 60 70 Length (cm) POLLOCK Long term mean age composition of fully exploited year classes 50- 40- CU -0 E 30- C 2 9 Bering Sea -0- Gulf of Alaska 20- 10- 2 4 6 8 10 12 Age (years) POLLOCK Growth rate percent per year (weight) 330- 320- 310- 300 100- 80- M, 0 60- Bering Sea 40- Gulf of Alaska 20- 2.5 4.5 6.5 8.5 10.5 12.5 Age (years) POLLOCK Distribution of biomass with age 20 -c 9 Bering Sea 15 -9- Gulf of Alaska E .2 10- c a) 2 0 (L 5 2.5 4.5 6.5 8a5 10.5 12.5 Age (years) POLLOCK Distribution of mortality with age of mean year class biomass 210 - 200 - 170- 160- 0, 'o 100- M M 80 - a) I 0 co W E 0 60- C a) 40- 0 Turnover Rate .65 0 Z> Bering Sea 20- Gulf of Alaska 2 4 6 8 10 12 Age (years) -18- 5.2 PACIFIC COD (Gadus macrocephalus The growth rate of Pacific cod in the Gulf of Alaska (mainly in Kodiak area) is considerably faster than in the Bering Sea, indicating the existence of separate stocks. (However, there might be some mixing of the stock in the western Gulf of Alaska with Bering Sea stock via Aleutian passages. This conclusion is partly supported by the variable age-length, weight data, especially as reported in literature.) The variations in available biometric data might also indicate problems with age determination. The long-term mean age coImposition of fully recruited year classes (based on rather meager data) indicates that younger year classes (3 and 4) are over-represented in the catches compared to expected normal age distribution of slightly fished stock. This might be caused by different depth distribution (and consequent different availability to fishery) of different age groups, as it is known that older cod seek deeper depths. Maximum biomass of cod occurs at medium ages (3.5 to 4.5 years) due to the rapid growth of this species. -19- PACIFIC COD (Gadus macrocephalus Gulf of Alaska Bering Sea Exploitable age (years) 3 to 8 3 to 8 length (cm) 40 to 85 40 to 85 weight 0.75 to 6.5 0.75 to 6.0 Catches - domestic (t) 3/ 500 8,500 foreign (t) - 34,000 37,000 Depth - distribution (m) l/ 100 to 400 100 to 400 M l/ 20 to 400 (S) fishing (m) 80 to 260 80 to 300 Maturity - age (years) 2/ 3 4 ? length.(cm) - 50 50 Spawning - season Jan to March Jan. to May area Along cont. slope of Alaska Penins. ? Fecundity 0.86 to 3 million 1 to 2 million At a turnover rate of .90 Exploitable biomass,% 64.1 67.0 Juvenile biomass,x 35.9 33.0 Growth rate, % per month Whole population 5.2 5.2 Juveniles 10.2 9.4 Adults 1.4 3.1 Deceased 7.0 6.00 Notes on food composition: Most important food items - shrimps, herring, sandlance, .flatfish, crabs, euphausids, and Atka Mackerel (Andreyasheve, 1937). l/ Some cod is assumed to be pelagic over deep water. 2/ Age and length when 50% of the population matures. 3/ Provisional estimates for 1980 (Murai et al. 1981). -20- 0 AGE-LENGTH-WEIGHT KEY Pacific cod (Gadus macrocephalus) 0 Bering Sea Gulf of Alaska l/ 2/ 3/ 4/ Age Length:-- Weight--- Length@- Weight- cm 9 cm 9 1 27.5 185.0 28.5 275.0 2 43.0 600.0 47.0 1050.0 3 53.0 1200.0 58.0 2100.0 4 62.0 2200.0 66.0 3150.0 5 68.5 3150.0 73.0 4370.0 6 74.5 4170.0 78.0 5220.0 441 7 80.0 5150.0 82.0 6050.0 8 84.5 (6075.0) 85.5 (6750.0) is I/ Research and commercial vessel data 1977-80 (Bakkala, 1981, unpublished); Japan-US Summary Report (unpublished) 1980; Pereyra et al, 1976; Kibesaki 1965; Observer Program 1976-1979; RACE data 1981 (sample size 3393). 2/ Calculated from length-weight data. 3/ Ronholt et al. 1978; Observer Program 1977-79; RACE data 1981 (sample size 4886) 4/ Ronholt et al. 1978; Westerheim, 1977. -21- LENGTH-WEIGHT KEY Pacific cod (Gadus macrocephalus) (Calculated from age-length and age-weight data) Bering Sea Gulf of Alaska Length Weight Weight cm 9 9 10 50.0 55.0 20 100.0 115.0 30 225.0 325.0 40 475.0 650.0 50 955.0 1275.0 60 1945.0 2375.0 70 3400.0 3400.0 80 5150.0 5550.0 -22- PACIFIC COD Age - length 90 - 80- 70 - 60- 50- E -c +1 40- 30- 20- 9 Bering Sea 10- - -0- Gulf of Alaska t 2 4 6 8 Age (years) -23- PACIFIC COD Age - weight 7000 - 6000 - Ilk 5000 - 4000- 3000- 2000 - 9 Bering Sea 1000- 0/ -0- Gulf of Alaska 2 4 6 8 Age (years) -24- PACIFIC COD Length - weight 6000 5000 - 4000 - 'a 3000 - T 2000 9 Bering Sea 1000- loe Gulf of Alaska 10 20 30 40 50 60 70 80 Length (cm) A 3 cp -25- IN PAC IF IC COD Long term mean age composition of fully exploited year classes 50 40 E % % 30 - 2 9 Bering Sea --q-- Gulf of Alaska a) 20 ------------ Normal Distribution" 10- I 3 4 5 6 7 Age (years) -26- PACIFIC COD Growth rate percent per year (weight) 290 - 280- 230'- 220- 9 Bering Sea Gulf of Alaska 1101 90 -C H 0 (D 4@ 3: 70- 0 C CL 50- 0 30 Ilk 10- 2.5 4.5 6.5 8.5 Age (years) -27- PACIFIC COD Distribution of biomass with age 20 - 91( 0 .c 15 - cc E .2 -0 10 c 5 Turnover Rate .90 9 Bering Sea Gulf of Alaska 0.8 2.5 4.5 6.5 8.5 10.5 Age (years) -28- PACIFIC COD Distribution of mortality with age 2201 21 0 170" 160 - 100 - cc c- 80 a CD c cc CD fro, E 0 60 c cu 40 Turnover Rate .90 0 Bering Sea 20 Gulf of Alaska 2 4 6 8 Age (years) -29- 5.3 SABLEFISH (Anaplopoma fimbria) There are some uncertainties in age determination of sablefish older than six years. It is known from tagging studies that there is considerable intermingling of the populations in the Bering Sea and in the Gulf of Alaska. It is, therefore, somewhat surprising that slight differences in length and weight at age occur between the two areas. This difference is also dk apparent in condition factor (length-weight relation). It might be caused by differences in availability of food for the more permanent resident fraction of the population in the two areas. -30- SABLEFISH (Anaplopoma fimbria) Gulf of Alaska Bering Sea Exploitable - age (years) (4) 5-12 (4) 6-12 length (cm) 52 to 80 60 to 80 weight (kg) 1.2 to 5.0 1.8 to 5.0 Catches - domestic W 20 40 foreign (t) 6100 2500 Depth - distribution (m) 50 to 1500 100 to 1200 fishing (m) 100 to 500 100 to 500 Maturity - age (years) Male 4 5 to 7 Female 5 length (cm) ? Male 55 ? Female 65 Spawning - season Oct. to March Dec. to April area 350 to 750 m Bowers Ridge and Aleutian Isl. regions Fecundity 100,000 to 1,000,000 100,000 to 1,300,000 At a turnover rate of .65 Exploitable biomass,% 53.9 36.1 Juvenile biomass,% .46.3 63.9 Growth rate,% per month Whole population 3.8 4.1 Juveniles 6.3 5.5 Adults 1.7 1.6 Deceased 5.7 5.7 Notes on food composition: Fish and crustaceans (pollock, herring, sandlance, shrimp, euphausids). l/ Provisional estimates for 1980 (Murai et al. 1981). -31- AGE-LENGTH-WEIGHT KEY Sablefish (Anoplopoma fimbria) Bering Sea Gulf of Alaska 1 2/ 3/ 4/ Age Length Weight7- Length= Weight- cm 9 Cm 9 1 21.0 125.0 22.5 125.0 2 35.0 375.0 37.2 475.0 3 45.0 675.0 47.5 875.0 4 52.0 1050.0 54.0 1375.0 5 56.7 1450.0 59.3 1950.0 6 61.0 1900.0 63.8 2600.0 7 64.5 2355.0 67.7 3250.0 8 68.0 2875.0 71.5 3925.0 9 71.0 3425.0 75.5 4665.0 10 74.0 3975.0 79.0 5375.0 11 77.0 4525.0 - - 12 80.0 5050.0 - 1/ 'Sasaki 1978; Sasaki 1981; Low et al. 1976; Pereyra et al. 1976. .2/ Low et al. 1978; Pereyra et al. 1976. 3/ Sasaki 1978, 1981; Kennedy and Pletcher 1968; Webb and Lockner 1973. 4/ Groundfish cruises 1978-79, 80-81. -32- LENGTH-WEIGHT KEY Sablefish (Anoplopoma fimbria) (Calculated from age-length and age-weight data) Bering Sea Gulf of Alaska Length Weight Weight cm 9- 9 10 35.0 35.0 20 120.0 120.0 30 275.0 300.0 40 502.5 575.0 50 925.0 1050.0 60 1800.0 2050.0 70 3225.0 3650.0 80 5025.0 5505.0 -33- SABLEFISH Age - length 80 W, 70 Jw 60 - fir 50 - 40 - fj 30 - 20 - Gulf of Alaska 10- e Bering Sea 2 4 6 8 10 12 Age (years) -34- SABLEFISH Age - weight 6000 - 5000 - 4000 - 3000 2000 - Bering Sea 1000 - Gulf of Alaska 2 4 6 8 10 12 Age (years) -35- SABLEFISH Length - weight 6000 5000 4000 - 3000 - 2000 - Bering Sea 1000- Gulf of Alaska 10 20 30 40 50 60 70 80 Length (cm) -36- SABLEFISH Long term mean age composition of fully exploited year classes 40- 30 - lei E 2 -C 20 - CO P W CL e - Bering Sea 10 - Gulf of Alaska 2 4 6 8 10 12 Age (years) -37- SABLEFISH Growth rate percent per year (weight) 2 0 8 Oj 27 2001 100 3@ 80 Ca W 60 0 Bering Sea 40 - Gulf of Alaska 20 - 2.5 4.5 6.5 8.5 10.5 12.5 Age (years) -38- SABLEFISH Distribution of biomass with age 15.0 - 12.5 - 10.0- T E 7.5 4@ c CD 5.0 - Bering Sea 2.5 - Gulf of Alaska 2.5 4.5 6.5 8.5 10.5 12.5 Age (years) -39- SABLEFISH Distribution of mortality with age 200 - 190 - 160 - 150 - 100 M 80 - ca a, E 0 0 c 60- 5 40- 0 Bering Sea 20- Gulf of Alaska I 1 1 2 4 6 8 10 12 Age (years) -40- S.4 YELLOWFIN SOLE (Limanda aspera) The biometric data on yellowfin sole is meager for the Gulf of Alaska. The data used in this summary for Gulf of Alaska originates from Auke Bay. The comparison of some older age-length data with the more recent data from the Bering Sea indicates that the growth rate for yellowfin sole might have changed. Yellowfin sole grows considerably faster in the Gulf of Alaska (temperature effect), but has a somewhat lower condition factor than the fish from the Bering Sea. Due to its faster growth in the Gulf of Alaska, the species comes under the fishery at an earlier age than in the Bering Sea. Due to the faster growth and earlier maturation of the yellowfin sole in the Gulf of Alaska, there are considerably fewer older fish in the latter area than in the Bering Sea--the age composition after the maturation being controlled by spawning stress mortality. Data in the literature about the size and age of maturity are controversial. 41 -41- YELLOWFIN SOLE (Limanda aspera) SE Alaska Bering Sea Exploitable - age (years) 4-13 6-15 length (cm) 20-30 20-30 weight (g) 100-500 100-375 Catches - domestic W l/ Minor fishery 9,600 foreign (t)-l/ 10 ? 80,000 Depth - distribution (m) 10-200 10-500 fishing (m) <100 <100 in summer 100-300 in winter Maturity - age (years) 3 to 6 4 to 8 length (cm) 17-25 50% female at 20-25 50% male at 16-18 Spawning - season May-June June to August area SE Alaska bays, Bristol Bay and north Kodiak on the shelf to Nunivak Isl. Fecundity Average 800,000 1,300,000 to 3,300,000 At a turnover rate of .65 Exploitable biomass,% 73.8 45.4 Juvenile biomass,%o 26.2 54.6 Growth rate, % per month Whole population 3.3 4.0 Juveniles 6.3 6.9 Adults 2.1 1.6 Deceased 4.9 5.9 Notes on food composition: Most important food items polychaetes, crustaceans, bivalve mollusks, echiuroids, ascidians. l/ Provisional estimates for 1980 (Murai et al. 1981). -42- AGE-LENGTH -WEIGHT KEY Yellowfin sole (Limanda asDera) Bering Sea Gulf of Alaska 4/ 1 2/ 3/ Age Lengtlr-/ Weight- Lengtli-_ Weight- cm R cm 9 1 5.0 6.3 8.3 7.0 2 9.0 17.5 14,8 25.5 3 12.5 31.3 19,5 60.0 4 15.8 51.2 22.7 100.5 5 18.5 75.0 24.8 142.5 6 20.8 98.8 26.2 195,0 7 22.8 126.3 27.7 245.0 8 24.3 158.8 28.8 290.0 9 25.7 186.3 29,7 335.0 10 26.8 213.0 30.8 387.5 11 27.7 242.5 31.5 431.5 da 12 28.5 273.0 32,2 470.0 13 29.0 306.2 32.6 505.0 14 29.5 340.7 15 30.0 375.0 l/ Bakkala et al. 1976; Weber & Shippen 1974; Maeda 1969; Bakkala & Smith 1978. 2/ Bakkala 1979 (79-20); Bakkala et al. 1976; Observer program 1974-79, Weber & Shippen 1975. 3/ Auke Bay data (1,576 fish); M/F Cruise 783. 4/ Auke Bay data. -43- LENGTH-WEIGHT KEY Yellowfin sole (Limanda aspera (Calculated from age-length and age-weight data) Bering Sea Gulf of Alaska Length Weight Weight cm 9 5 6.3 6.5 10 20.2 15.8 15 45.6 28.8 20 86.5 67.5 25 167.5 150.0 30 375.0 345.0 -44- YELLOWFIN SOLE Age - length 40 - 30 - E .C w 20 - /0 Bering Sea 10 - Gulf of Alaska 2 4 6 8 10 12 14 16 Age (years) -4S- YELLOWFIN SOLE Age - weight 500- 400- 300 - T 200- Bering Sea 100- Gulf of Alaska 2 4 6 8 10 12 14 16 Age (years) -46- YELLOWFIN SOLE Length - weight 400 - 300 - 200 - 9 - Bering Sea 100 - 0 - Gulf of Alaska 100, 5 10 15 20 25 30 Length (cm) -47- AL w YELLOWFIN SOLE Long term mean age composition of fully exploited year classes 25 20 - E 15 0 a5 10 CL Bering Sea 5 Gulf of Alaska dft. 2 4 6 8 10 12 14 16 Age (years) -48- YELLOWFIN SOLE Growth rate percent per year (weight) 270 - 260 - 180 140- 120 - 100 - (U -C C2 80 - C a. 60 - 9 Bering Sea 40 - -0- Gulf of Alaska 20 - 2.5 4.5 6.5 8.5 10.5 12.5 14.5 Age (years) -49- all YELLOWFIN SOLE Distribution of biomass with age 15 Bering Sea 10- Gulf of Alaska E c 5 CL 2.5 4.5 6.5 8.5 10.5 12.5 14.5 16.5 Age (years) -50- YELLOWFIN SOLE Distribution of mortality with age 240- 230- 170- 160- 136- E 0 110- cc 90- E 0 (U 70- L) a) CL > M 50- 0 30- Turnover Rate .65 Bering Sea Gulf of Alaska 10 2 4 6 8 10 12 14 16 Age (years) _Sl_ 5.5 GREENLAND TURBOT (Reinhardtius hippoglossoides) Greenland turbot (or Greenland halibut) occurs both in the Bering Sea and in the Gulf of Alaska. However,- no biometric data are available from the Gulf of Alaska. As Greenland turbot is a very minor constituent of U.S. catch and, as concentrations of these species occur in deeper water (200 to 700 m) out of routine resource survey range, only a minimal amount of biometric data on this species exists. The long-term mean age composition of fully exploited year classes indicates that the first fully exploited age (5 years) is probably over-represented because younger fish occur in shallower water and are easily available to resource surveys. The decrease of the frequency of year classes between 6 and 16 years indicates that the species is but slightly exploited. The data on maturity of this species is meager indeed. Judging from the distribution of mortality with age, it seems that 50% maturity occurs at age 10 to 11 whereafter the spawning stress mortality follows a normal path. -52- GREENIAND TURBOT (Reinhardtius hippoglossoides) Gulf of Alaska Bering Sea Exploitable - age (years) No data available (4) 5 to 16 - length (cm) (35) 40-to 75 - weight (cm) for Gulf of Alaska 600 to 4000 Catches - domestic M Minor (5) foreign (t) 30,000 Depth - distribution (m) 60 to 900 fishing (m) 80 to 600 Maturity - age (years) 13-14 length (cm) 50 to 70 Fecundity (15,000 to 215,000) At a turnover rate of .65 Exploitable biomass.,% 61.3 Juvenile biomass,% 38.7 Growth rate, % per month Whole population 3.2 Juveniles 5.7 Adult 1.6 Deceased 5,0 Main food items: fish, squids, shrimps, amphipods. to -53- AGE-LENGTH-WEIGHT KEY Greenland turbot (Reinhardtius hippoglossoides) Bering Sea Lengtlrl/ Weight Age cm 9 0.8 36.0 No data available for 1 11.8 48.0 Gulf of Alaska 2 23.0 152.0 3 31.4 340.0 4 39.5 596.0 5 44.5 904.0 6 50.5 1260.0 7 54.3 1620.0 AL 8 57.9 1980.0 9 61.5 2320.0 10 64.4 2620.0 11 67.0 2920.0 12 69.8 3180.0 13 72.0 3440.0 14 75.5 3632.0 15 76.7 3800.0 16 78.0 3920.0 l/ Pereyra et al. 1976; Bakkala and Smith 1978j Mikava, Masao 1963. -54- LENGTH-WEIGHT KEY Greenland turbot (Reinhardtius hippoglossoides) (Calculated from age-length and age-weight data) Bering Sea Length Weight cm 9 10 44.0 No data available.for 20 120.0 Gulf of Alaska 30 296.0 40 636.0 50 1240.0 60 2136.0 70 3200,0 80 4087.0 0 -55- a GREENLAND TURBOT 9 Age - length 100 - 80 - 60 - -S@ % cn C: Q3 -j 40 - 9 Bering Sea 20- -W I I I I I 1 1 2 4 6 8 10 12 14 1'6 Age (years) I -1 j -56- GREENLAND TURBOT Age - weight 4800 4000 - 3200 - S 2400 - T 1600 - G Bering Sea 800 - 2 4 6 8 10 12 14 16 Age (years) -S7- GREENLAND TURBOT Length - weight 3500 - 3000 - 2500 - 2000 - .C 1500 - 1000 - 500 - Bering Sea I 10 20 30 40 50 60 70 Length (cm) -58- GREENLAND TURBOT Long term mean age composition of fully exploited year classes 30 25 - 20 - E '@6 15 0 C CL 10 - 9 Bering Sea 5 2 4 8 10 12 14 16 Age (years) 5 _S9- -4k GREENLAND TURBOT Growth rate percent per year (weight) 220 200 130 - 0 120 - 100 - L CD 80 - 2 C CL 60 - 40 - Bering Sea 20 - J- 0.8 2.5 4.5 6.5 8.5 10.5 12.5 14.5 16.5 Age (years) -60- GREENLAND TURBOT Distribution of biomass with age 30 25 20 LM cu co E 15 .0 c a) 2 Turnover Rate .65 0- 10 Bering Sea 5 2.5 4.5 6.5 8.5 10.5 12.5 14.5 16.5 Age (years) GREENLAND TURBOT Distribution of mortality with age 200 - 190 130 120 - -C .0 Q) ca IUU 0 CU 0 E 80 0 c W 2 W CL c 60 0 40 Turnover Rate .65 20 - 9 Bering Sea 0.4 2 4 6 8 10 12 14 16 Age (years) -62- 5.6 FLATHEAD SOLE (Hippoglossoides elassodon) The available data indicate that the juveniles of flathead sole grow faster in the Gulf of Alaska than in the Bering Sea. This is expected according to available knowledge of the effect of temperature on the growth. However, the data show that the older fish grow longer and heavier in the Bering Sea. This might arise from questionable data or be caused by the migrations of older, large fish toward northern distribution boundaries. -63- FLATHEAD SOLE (Hippogloss ides elassodon) Gulf of Alaska Bering Sea Exploitable - age (years) 6-16 6-16 length (cm) 25-37 25-40 weight (g) 130-625 130-675 Catches - domestic Minor fishery Minor fishery foreign (t) 700 (est) 25,000 (est) Depth - distribution (m) 50-400 In winter on slope and deeper part of shelf; in summer widely distributed 60-450 fishing (m) up to 200 Winter 90-450 Summer 110-140 Maturity - age (years) 3 ? length (cm.) 18 ? Spawning - season April-May June-July area (Not localized) (Not localized) Fecundity 50@000-160,000 50,000-160,000 At a turnover rate of .65 Exploitable biomass,,% 41,1 42.8 Juvenile biomass, @"' 58.9 57.2 Growth rate,% per month Whole population 4.0 4..0 Juveniles 5.9 5.8 Adults 1,2 1.6 Deceased 5.5 5,3 Notes on food composition: Most important food items ophiarids, shrimps, amphipods, fish, mollusks. -64- AGE-LENGTH-WEIGHT KEY Flathead sole (Hip_poglossoides elassodon) Bering Sea Gulf of Alaska 1 2/ 3/ 4/ Agge Lengthil/ Weighv- LengtY- Weight- Cm R cm 9 1 9.3 11.0 9.3 10.5 2 14.1 25.8 14.1 25.0 3 17.5 45.0 18.3 50.0 4 20.2 68.5 22.0 85.0 5 22.7 98.0 24.6 122.5 6 24.8 132.0 26.5 153.5 7 27.0 177.5 28.0 187.0 8 29.2 230.0 29.5 225.0 9 31.3 288.0 30.5 263.0 10 32.8 345.0 32.0 297.0 11 34.5 405.0 33.3 340.0 12 35.5 463.0 34.5 385.0 13 36.7 514.0 35.5 423.0 14 37.8 565.0 36.3 457.0 15 38.9 608.5 37.3 500.0 16 40.0 655.0 38.0 530.0 Pereyra et al. 1976; Crab-Groundfish survey data 1971-78. Pereyra et al. 1976. 3/ Ronholt et al. 1978; M/F cruise 75-1 dSta. 4/ Ronholt et al. 1978; M/F cruise 75-1 data; RACE survey data. -65- LENGTH-WEIGHT KEY Flathead sole (Hippoglossoides elassodon .(Calculated from age-length and age-weight data) Bering Sea Gulf of Alaska Length Weight Weight cm 9 5 5.0 4.5 10 15.0 13.0 15 31.5 27.5 20 67.5 65.0 25 137.5 127.5 30 260.0 240.0 35 435.0 405.0 40 655.0 620.0 -66- FLATHEAD SOLE Age - length 40- 30- E CD c 20- 40 e Bering Sea 10- Gulf of Alaska 2 4 6 8 10 12 14 16 Age (years) AM -67- FLATHEAD SOLE Age - weight 700 600 - 500 - 400 01, eel 300 - 200 Bering Sea 100- Gulf of Alaska 2 4 6 8 10 12 14 16 Age (years) -68- FLATHEAD SOLE Length - weight 700 600 - 500 - 400 - 300 - 200 - e Bering Sea 100- -0- - Gulf of Alaska 5 10 15 .20 25 30 35 40 Length (cm) -69- FLATHEAD SOLE Long term mean age composition of fully exploited year classes 30 - 25 - 20 - -0 E 70- 0 15 - C) Bering Sea 10 Gulf of Alaska N-, 5 6 8 10 12 14 16 Age (years) -70- FLATHEAD SOLE Growth rate percent per year (weight) 140 - 130 - 100 - C 80 0 V) 60- Q CU Turnover Rate .65 9 Bering Sea 40- Gulf of Alaska 20 - 46- 2.5 4.5 6.5 8.5 10.5 12.5 14.5 16.5 Age (years) FLATHEAD SOLE Distribution of biomass with age 15 - Turnover Rate .65 ow Bering Sea 10- --0-- Gulf of Alaska E .2 5 2.5 4.5 6.5 8.5 10.5 12.5 14.5 16.5 Age (years) -4 -72- FLATHEAD SOLE Distribution of mortality with age 150 - 140 - Bering Sea 1200 - Gulf of Alaska c 100 c M W 80 E 0 c a) CO 60 .C: M 0 40 - 20 - 2 4 6 8 10 12 14 16 Age (years) -73- 5.7 ROCK SOLE (Lepidopsetta bilineata) The unpublished length-weight-age data from the Gulf of Alaska (NOAA ship Miller Freeman cruises) are variable and in some cases show even slower growth of the species in the Gulf of Alaska than in the Bering Sea. On the other hand, Levings (1967) gives slightly higher length-at-age values for Bristol Bay and Gulf of Alaska than the data presented in 0 this summary, which are adjusted down with the unpublished data from NWAFC. Furthermore, Levings (1967) and Forrester and Thomson (1969) give considerably higher values of length at age in Northern Hecate Strait. This indicates the presence of a separate local, fast growing (higher temperature) stock in this strait. The data of this stock are excluded from the present summary. The differences in the age of full recruitment to the fishery between the two areas is influenced by the type of fishery and availability (migrations) of the fish as well as the occurrence of this species as bycatch in some fisheries. -74- ROCK SOLE (Lepidopsetta bilineata) Gulf of Alaska Bering Sea Exploitable - age (years) 5-14 6-14 length (cm) 22-35 25-40 weight (g) 100-800 150-900 Catches - domestic (t) Minor fishery Minor fishery foreign (t) 900 36,000 Depth - distribution (m) 20-300 50-400 ? fishing (m) 20-100 winter 39-300 20-50 summer Maturity - age (years) 4-6 5-7 length (cm) male 18 female 28 male 20 ? female 30 ? Spawning - season March to June March to June area Around Kodiak Isl. SW of St. Matthews Isl. on wintering grounds Fecundity Average 200,000 150,000 to 400,000 At a turnover rate of .65 Exploitable biomass,% 56.1 49.0 Juvenile biomass,% 43.9 51.0 Growth rate, % per month Whole population 3.9 3.9 Juveniles 6.4 5.9 Adults 2.0 1.8 Deceased 5.3 5.2 Notes on food composition: Most important food items - po lychaetes, mollusks, crustaceans (mostly shrimp), and occasionally sand lances. -75- AGE-LENGTH-WEIGHT KEY Rock sole (Lepidopsetta bilineata) Bering Sea Gulf of Alaska l/ 2/ 3/ 4/ Age Length= Weight- Length-,-- Weight- CM, 9 cm 9 1 8,3 8.5 6.7 8.5 2 1217 23.5 12.0 23..5 3 16,1 41,5 16.0 38.,5 4 1.8.9- 71...5 2010 61!5 5 21,4 106.0- 2215 94.0 6 2317 148,0- 2413 136,0 7 26.0 198,0. 26,4 19010 8 28,4 26.2.5 27.5 253.5 9 3017 332.0 2819 325'0 10. 32.8 415..0 30, G 40.4.5 11 .34.7 50815 31,4 483fO 12 36-06 61(1,0. 32,5 580.0 13 38.3 70.6.0- 33.15 675.,0 14 3q.8 810.,0 34.4 765.0 15 40,8 897,5 34,9 790.0 l/ Crab@groundfish.survey lq-71-78; Levings 1967; Qbsei@yer Prq@gram 1974-n78, M/F crui@ses 77-1 and 78-3; Pereyra et al, lq76- 3/ Crabgroundfish survey 1971@78; Levings 196.71, Observer Prpglr'7am 1974-78; Forrester and Thompson 1969, Pereyra et al, 1976; 7adeev 19.6.5; Observer Program 1974@78, -76- LENGTH-WEIGHT KEY Rock sole (LepidopseXta bilineata) .(Calculated from age-length and age-weight data) Bering Sea Gulf of Alaska Length Weight Weight cM__ 9 5 5.0 5.0 10 15.0 15.0 15 40.0 40.0 20 75.0 68.0 25 145.0 143.0 30 278.0 403.0 35 500.0 790.0 40 835.0 -77- ROCK SOLE Age - length 50 - 40- 30- -C C W -j 20 Bering Sea Gulf of Alaska 10- N. Hecate Strait 2 4 6 8 10 12 14 16 Age (years) -78- ROCK SOLE Age - weight 1000- 800 - 600- 400- 9 Bering Sea 200- 0 Gulf of Alaska L. e- r J- I 2 4 6 8 10 12 14 16 Age (years) 4i @79- ROCK SOLE Length - weight 1000- 800- Bering Sea 600- Gulf of Alaska 400- 200- 10 20 30 40 50 Length (cm) -80- ROCK SOLE Long term mean age composition of fully exploited year classes 35 - 30 - 25 - -E; 20 - E C 2 C 15 - CL 10- 9 Bering Sea 5- -41- Gulf of Alaska N.. 2 4 6 8 10 12 14 16 Age (years) ROCK SOLE Growth rate percent per year (weight) 180- 170 100- Turnover Rate .65 9 Bering Sea .0 a) 80- -0-- Gulf of Alaska 0 0 60- a. 40- 20- 2.5 4.5 6.5 8.5 10.5 12.5 14.5 Age (years) -82- ROCKSOLE Distribution of biomass with age 10 0 LM co E 5- 0 4@ c Turnover Rate .65 cu 9 Bering Sea CL Gulf of Alaska I 2.5 4.5 6.5 8.5 10.5 12.5 14.5 16.5 Age (years) -83- ROCK SOLE Distribution of mortality with age 170 160 - 100 cu 80- c ca 4) E 0 - 60 W 0 CL E >@ 40- Turnover Rate .65 0 9 Bering Sea 20- Gulf of Alaska 2 4 6 8 10 12 14 16 Age (years) -84- 5.8 PACIFIC OCEAN PERCH (Sebastes alutus) The length and weight at age of this species are nearly identical in the Gulf of Alaska and in the Bering Sea, indicating that the same stock inhabits both regions. (The growth rate of Pacific ocean perch caught off the Canadian coast and southward has, however, considerably higher growth rate, belonging to another stock.) The age (and size) composition of catches from the Bering Sea shows that older and larger specimens occur in this region. This seems to be in conformity with general phenomena that older and larger specimens accumulate at the colder boundaries of general distribution. For this reason the fully exploited year class in the Bering Sea is 11 years old whereas in the Gulf of Alaska 7-year-olds are fully exploited. The data on maturity and spawning areas and times are meager for Pacific ocean perch. -85- PACIFIC OCEAN PERCH (Sebastes alutus) Gulf of Alaska Bering Sea Exploitable - age (years) 7 to 20 11 to 20 length (cm) 25 to 40 30 to 40 weight (g) 250 to 850 500 to 850 Catches - domestic WY 20 50 foreign W Y 12,500 15,000 Depth - distribution (m) 180 to 3000 summer 160 to 3000 summer 275 to 3000 winter 300 to 3000 winter fishing (m) 180 to 300 150 to 350 Maturity - age (years) 4 to 6 4 to 8 length (cm) 20 to 30 20 to 30 Spawning - season March to June March to May area Deep water J>300 m Deep water >300 m Fecundity 10,000 to 68,000 27,000 to 180,000 At a turnover rate of .65 Exploitable biomass,% 44.0 18.5 Juvenile biomass,% 56.0 81.5 Growth rate, % per mos. Whole population 3.7 3.7 Juveniles 5.6 4.4 Adults 1.2 0.7 Deceased 6.4 6.3 Notes on food composition: Most important food items copepods, euphausids, shrimp, squid, smelts, myctophids, other fish. l/ Provisional estimates for 1980 (Murai et al. 1981) 2/ Some parts of Pacific Ocean perch population migrates and feeds over deep water. -86- AGE-LENGTH-WEIGHT KEY Pacific Ocean perch (Sebastes alutus) Bering Sea Gulf of Alaska 1/ 2/ Ir3 4/ Age Length@ Weight- Lengt Weight- Cm 9 Cm 9 1 7.2 5.0 7.1 5.5 2 12.0 20.0 11.8 22.5 3 16.0 51.0 16.0 54.5 4 18.9 85.0 19.1 90.5 5 21.5 130.5 21.7 135.0 6 24.0 178.0 24.2 185.0 7 26.6 230.0 26.7 240.0 8 27.8 295.0 28.1 310.0 9 29.2 353.0 30.2 370.0 10 31.0 420.0 31.5 440.0 11 32.2 393.5 32.4 515.0 12 33.5 555.0 33.9 582.5 13 34.5 620.0 35.0 640.0 14 35.5 670.0 35.8 695.0 15 36.2 725.0 36.7 745.0 16 37.1 767.5 37.5 795.0 17 37.8 802.0 38.2 830.0 18 38.5 824.0 39.0 855.5 19 39.0 843.0 39.6 872.0 20 40.0 852.0 40.6 890.0 Pereyra et al. 1976; Major and Shippen 1970; Paraketsov 1963. Pereyra et al. 1976; Observer Program 1976-79; Major and Shippen 1970: Pautov 1972; Paraketsov 1963. 3/ Groundfish survey 1979-80; Westerheim 1975; Chikuni 1975. Groundfish survey 1979-80; Ronholt, Shippen and Brown 1978. -87- LENGTH-WEIGHT KEY Pacific Ocean perch (Sebastes alutus) (Calculated from age-length and age-weight data) Bering Sea Gulf of Alaska Length Weight Weight cm 9 9 5 2.5 2.5 10 10.0 10.0 15 40.0 42.5 20 94.0 100.0 25 195.0 210.0 30 375.0 382.0 35 635.0 645.0 40 852.0 885.0 -88- PACIFIC OCEAN PERCH Age - length 40- 30- 20- cu Bering Sea 10- Gulf of Alaska 2 4 6 8 10 12 14 16 18 20 Age (years) -89- PACIFIC OCEAN PERCH Age - weight 1000 - 800 - 600 - 400 - 9 Bering Sea 200- - Gulf of Alaska 2 4 6 8 10 12 14 16 18 20 Age (years) -90- PACIFIC OCEAN PERCH Length - weight 1000- 800- 600- T a) 400- 19 Bering Sea 200- 0 Gulf of Alaska -j- 5 10 15 20 25 30 35 40 Length (cm) PACIFIC OCEAN PERCH Long term mean age composition of fully exploited year classes 30 - Bering Sea 25- Gulf of Alaska 20 E :3 -F@ 15 C W CL 10- 5 8 10 12 14 16 18 20 Age (years) -92- PACIFIC OCEAN PERCH Growth rate percent per year (weight) 350 300 160 - 140 - 120 - -C .21 100 - 0 80- EL 60- Turnover Rate .65 0 Bering Sea 40- 0 Gulf of Alaska 20- 2.5 4.5 6.5 8.5 10.5 12.5 14.5 16.5 18.5 20.5 Age (years) -93- PACIFIC OCEAN PERCH Distribution of biomass with age 12.5 - 10.0- LM CD Turnover Rate .65 0 Bering Sea M 0 Gulf of Alaska E 7.5 0 c W p 0- 5.0 - 2.5- 2.5 4.5 6.5 8.5 10.5 12.5 14.5 16.5 18.5 20.5 Age (years) -94- PACIFIC OCEAN PERCH Distribution of mortality with age 260- 250- 230 220 .'-I 140- Turnover Rate .65 19 Bering Sea 17; 120- J_- Gulf of Alaska .21 CL) loo- c M cu E 0 80- c cu 60- > 40- 20- 2 4 6 8 10 12 14 16 18 20 Age (years) -95- 5.9 ATKA M&CKEREL (Pleurogrammus monopterygius) Doubts can be expressed about the age determination of Atka mackerel, especially age 1. The weight at age data of this species are also questionable. Consequently the computed data pose the same questions as the basic input data. -96- ATKA MACKEREL (Pleurogrammus monopterygius) Gulf of Alaska Bering Sea Exploitable - age (years) 2 to 6 2 to 6 length (cm) 25 to 38 20 to 35 weight (g) 300 to 600 200 to 500 Catches - domestic (t)-!/ 3 265 foreign(t) -1/ 13,162 20,255 Depth - distribution (Northern Gulf of Alaska) (Southern part of Bering Sea fishing (m) 110 to 250 70 to 150 Maturity - age (years) 3 3 length (cm) ca 33 ca 33 Spawning - season June, July, August June, July, August area Passes between Atka and Amlia Island, Atka and Adak Islands, Umnak and Unalaska, Shumagin Island. Fecundity 5,000 to 43,000 5,000 to 43,000 At a turnover rate of .65 Exploitable biomass,,% 55.3 51.7 Juvenile biomass.% 44.7 48.3 Growth rate,% per month Whole population 4.1 3.9 Juveniles 6.9 6.4 Adult 1.8 1.6 Deceased 3.8 4.0 Notes on food composition: Plankton, small fish, mollusks, worms, and hydroids. l/ Provisional estimates for 1980 (Murai et al. 1981). -97- AGE-LENGTH-WEIGHT KEY Atka mackerel (Pleurogrammus monopterygius) Bering Sea Gulf of Alaska 1 2/ Ir3/ 4/ Age Lengtlr-/ Weight@ Lengt Weight- cm 9 cm & 1 20.6 150.0 22.8 162.5 2 27.1 275.1 30.0 308.0 3 31.0 374.3 33.5 425. 0 4 32.7 438.5 35.3 502.0 5 33.8 482.0 36.2 550.0 6 34.6 515.0 36.8 580.0 7 35.0 545.0 37.0 602.0 l/ Summary of observer data 1977-79 2/ Summary of observer data 1977-79 3/ Low et al. 1979. Survey cruise data 1981. 4/ Survey cruise data (raw). Survey cruise data 1981. _98- LENGTH-WEIGHT KEY Atka mackerel (Pleurogrammus monopterygius) (Calculated from age-length and age-weight data) Bering Sea Gulf of Alaska Length Weight Weight cm 9 9 5 18.0 18.0 10 45.0 45.0 15 90.0 85.0 20 145.0 132.5 25 226.0 200.0 30 341.5 310.0 35 545.0 490.0 -99- ATKA MACKEREL Age - length 40- 35 - AIV Ole 30 - 25 - 20 - 15 - 10 - Bering Sea 5 Gulf of Alaska 2 3 4 5 6 7 Age (years) -100@ ATKA MACKEREL Age - weight Gulf of Alaska 700 - 600 - 500 400 - -c 300 - 200 - 9 Bering Sea 100 Gulf of Alaska 1 3 4 5 6 7 Age (years) ATKA MACKEREL Length - weight 600- 500- 400- 300- 200- Bering Sea 100 Gulf of Alaska J 5 10 15 20 25 30 35 Length (cm) -102- ATKA MACKEREL Long term mean age composition of fully exploited year classes 60 - 50 - 40- E C 30- 0 9 Bering Sea 20- -0- Gulf of Alaska 10- 3 4 5 6 7 Age (years) -103- ATKA MACKEREL Growth rate percent per year (weight) 100 - 80 - -C 60 - 0 9 Bering Sea (m -C 40- -0- Gulf of Alaska (v 0- 20 1.5 2n5 3!5 4.5 5.5 6.5 Age (years) -104- ATKA MACKEREL Distribution of biomass with age 30 - 25 - 20 - cu cu E 15 c: Turnover Rate .65 cu 9 Bering Sea CL 10 -0- Gulf of Alaska 5 1.5 2.5 3.5 4.5 5.5 6.5 7.5 Age (years) -105- ATKA MACKEREL Distribution of mortality with age 100 101, 80 - sell co c 60 ca Q) E 0 40 cu OL r- Turnover Rate .65 > 9 Bering Sea .t-- '@Z6 20 --0-- Gulf of Alaska t 0 1 2 3 4 5 7 Age (years) -106- 5.,10 PACIFIC HERRING (Clupea harengus pallasi There are local races of herring which have different growth rates. In the Bering Sea there are two races--the slower growing race in Norton Sound and the faster growing Bering Sea herring. The latter seems to undertake considerable seasonal migrations. There are several local races of herring in the Gulf of Alaska which seem to have similar growth rates. Some earlier data from the Kodiak area indicate the presence of faster growth herring which might be a 41 local race or Bering Sea herring which have migrated from Unimak Pass. -107- PACIFIC HERRING (Clupea harengus pallasii) Gulf of Alaska SE Bering Sea Exploitable - age (years) (3) 4-9 (3) 4-9 length (cm) 18-24 22-30 weight (g) 80-220 100-380 Catches - domestic W l/ 9,000 7,000 foreign W l/ ? 8,500 Depth - distribution Continental shelf Continental slope and shelf fishing Coastal areas Coastal areas Maturity - age (years) 3 3 length (cm) 18 20 Spawning - season March - April May - July area Coastal zone, bays Bristol Bay to Kotzebue Sound, protected areas Fecundity 12,000 to 80,000 26,000 to 70,000 At a turnover rate of .90 Exploitable biomass,% 35.14 44.3 Juvenile biomass@% 64.6 55.7 Growth rate, % per month Whole population 5.2 5.1 Juveniles 7.3 7.5 Adults 1,5 2,0 Deceased 6,6 6,4 Notes on food composition: Plankton, fish larvae, amphipods, decapods, sagittae, euphausiids, juvenile fish. I/ Provisional estimates for 1980 (Murai et al. 1981). -108- AGE-LENGTH-WEIGHT KEY Pacific herring (Clupea harengus pallasii S.E. Bering Sea Norton Sound Gulf of Alaska 1 2/ 3 4/ 15 6/ Length-/ Weight- Lengt Weight- Lengt r_/ Weight--;- Age cm 9 cm 9 cm 9 1 9.8 11.3 9.8 11.3 8.9 11.8 2 15.8 37.5 14.6 34.5 14.3 37.5 3 19.5 73.0 17.5 60.5 17.5 66.3 4 22.3 113.8 19.4 88.8 19.5 96.3 5 24.5 158.8 20.9 115.3 20.8 125.0 6 26.2 205.0 21.7 141.3 21.6 151.3 7 27.5 253.3 22.3 167'."5 22.4 170.0 8 28.6 301.3 22.6 193.2 22.9 185.3 9 29.5 343.8 22.9 216.5 23.2 197.5 10 30.4 377.5 23.0 237.0 23.4 207.5 I/ Barton, 1978; Shaboneev, 1965; Skud, 1963. 2/ Rumyantsev and Darda, 1970, Shaboneev, 1965 3/ Barton, 1978. 4/ Barton, 1978. 5/ Barton, 1978; Skud, 1963. 6/ Reid, 1971; Skud, 1963. _109- LENGTH-WEIGHT KEY Pacific herring (CLi@ea harengus pallasii) (Calculated from age-length and age-weight data) S.E. Bering Sea Norton Sound Gulf of Alaska Length Weight Weight Weight cm 9 9 9 5 3.8 3.8 3.8 10 12.3 13.8 12.5 15 33.0 41.5 41.0 20 77.5 112.0 114.0 22.5 117.5 175.0 176.0 25 170.0 - - 30 360.0 PACIFIC HERRING Age - length 35 - 30- 25 - 20 - ie .49 c 15- 10 - 9 S.E. Bering Sea ......... ........ Norton Sound 5- Gulf of Alaska 2 4 6 8 10 Age (years) PACIFIC HERRING Age - weight 400 350 - 300 - 250 - -a -c 200 - T J3 cu 150 100 0 S.E. Bering Sea ......... ........ Norton Sound 50- Gulf of Alaska 2 4 6 8 10 Age (years) X PACIFIC HERRING Length - weight 400- 350 - 300- 9 S.E. Bering Sea ......... ........ Norton Sound 250 - Gulf of Alaska 200- 150- 100- 50- 5 10 15 20 22.5 25 30 Length (cm) PACIFIC HERRING Long term mean age composition of fully exploited year classes 50 40 - 30- E 20 - CU P CU Turnover Rate .90 CL 9 S.E. Bering Sea io- Gulf of Alaska 2 4 6 8 10 Age (years) PACIFIC HERRING Growth rate percent per year (weight) 240 - 230 - 220 - 210 100 - S.E. Bering Sea 80- Gulf of Alaska 0 C 60 CL 40 20 2.5 4.5 6.5 8.5 10.5 Age (years) PACIFIC HERRING Distribution of biomass with age 20 - Turnover Rate .90 S.E. Bering Sea LM Gulf of Alaska lu 15 co E .2 10- c cu CL 5 2.5 4.5 6.5 8.5 10.5 Age (years) PACIFIC HERRING Distribution of mortality with age 190 180 100 - LM CL) M 80 - c M E 4e @O 60 - C cl 40 0 Turnover Rate .90 S.E. Bering Sea 20 Gulf of Alaska 2 4 6 8 10 Age (years) 6. REFERENCES (data sources) And-riyashev, A. P. 1937. K poznaniyu ikhtiofauny Beringova i Chukotskogo morei (A contribution to the knowledge of the fishes from the Bering and Chukchi Seas). Akad. Y I Nauk SSSR, Zool. Inst., Issled. Morel 25 (Issled. Dal'nevost. Morei 5): 292-355. In Russian. (Transl. 1955, U.S. Fish Wildl. Serv., Spec. Sci. Rep. Fish. 145.) Bakkala, R. G. 1979. Population characteristics and ecology of yellowfin sole. In Fisheries oceanography - eastern Bering Sea shelf, NWAFC Processed Rep. 79-20, p. 280-329. Northwest and Alaska Fish. Cent., Natl. Mar. Fish. Serv., NOAA, 272S Montlake Blvd. E., Seattle, WA 98112. Bakkala., R., L. Low, and V. Wespestad. 1979. Condition of groundfish resources in the Bering Sea and Aleutian area. Unpubl. manuscr., 107 p. Northwest and Alaska Fish. Cent., Natl. Mar. Fish. Serv., NCAA, 2725 Montlake Blvd. E., Seattle, WA 98112. Bakkala, R. G., and G. B. Smith. 1978. Demersal fish resources of the eastern Bering Sea: spring 1976. Processed Rep., 234 p. Northwest and Alaska Fish. Cent., Natl. Mar. Fish. Serv., NCAA, 2725 %ntlake Blvd. E., Seattle, WA 98112. Bakkala, R., and G. Hirschhorn. 1976. Status of yellowfin sole (Limanda aspera in the eastern Bering Sea through 1976. Unpubl. manuscr., 20 p. Northwest and Alaska Fish. Cent., Natl. Mar. Fish. Serv., NCAA, 2725 Montlake Blvd. E., Seattle, WA 98112. -118- Barton., L. H. 1978. Finfish resource surveys in Norton Sound and Kotzebue Sound. In Environmental assessment of the Alaskan continental shelf, Final Reports, Biological Studies 4:75-313. U.S. Dep. Commer., Natl. Oceanic Atmos. Admin., Off. Mar. Pollut. Assess., Boulder, Colo. Chikuni., S. 1975. Biological study of the population of the Pacific ocean perch in the North Pacific. Bull. Far Seas Fish. Res. Lab. 12:1-119. OF Dudnik., Y. I., and E. A. Usol'tsev. 1964. 0 selldi vostochnol chasti Beringova morya (The herrings of the eastern part of the Bering Sea). Tr. Vses. Nauchno-issled. Inst. Morsk. Rybn. Khoz. Okeanogr. 49 (Izv. Tikhookean. Nauchno-issled. Inst. Morsk. Rybn. Khoz. Okeanogr. 51):225-229. In Russian. (Transl. by Israel Program Sci. Transl., 1968, p. 236-240 in P. A. Moiseev (editor), Soviet fisheries investigations in the northeast Pacific, Pt. 2, avail. U.S. Dep. Comer., Natl. Tech. Inf. Serv., Springfield, Va., as TT 67-51204.) Fadeev, N. S. 196S. Sravnitellnyi ocherk biologii kambal iugo-vostochnoi, chosti Beringova moria i sostoianie ikh zapasov (Comparative outline of the biology of flatfishes in the southeastern part of the Bering Sea and condition of their resources). Tr. Vses. Nauchno-issled. Inst. Morsk. Rybn. Khoz. Okeanogr. S8 (Izv. Tikhookean. Nauchno-issled. Inst. Morsk. Rybn. Khoz. Okeanogr. 53): 121-138. In Russian. (Transl. by Israel Program Sci. Transl., 1968, p. 112-129 in P. A. Moiseev (editor), Soviet fisheries investigations in the northeast Pacific, Pt. 4, avail. U.S. Dep. Comer., Natl. Tech. Inf. Serv., Springfield, Va., as TT 67-S1206.) _119- Forrester, C. R., and J. A. Thomson. 1969. Population studies on the rock sole (Lepidopsetta bilineata) of northern Hecate Strait, British Columbia. Fish. Res. Board Can. Tech. Rep. 108, 104 p. Kainmer, S., and D. Gunderson. 1976. Weight-length relationships for six species of demersal. fish collected in the Bering Sea during late summer and early fall, 1975, Unpubl. manuscr, 16 p. Northwest and Alaska Fish. Cent., Natl. Mar. Fish. Serv., NOAA, 2725 Montlake Blvd. E., Seattle, WA 98112. Kennedy, W. A., and F. T. Pletcher. 1968. The 1964-65 sablefish study. Fish. Res. Board Can. Tech. Rep. 74, 74 p. Kibesake, 0. 1965. Demersal fish resources in the northern Pacific. Jpn. Fish. Res. Conserv. Assoc., Fish. Res. Serv. 11:1-45. Kobayaski, K. 19S8. Larvae and young of the Atka mackerel, Pleurogrammus monopterygius (Pallas) in the North Pacific. Bull. Fac. Fish. Hokkaido Univ. 8(4):297-303. Kolloen, L. N. 1947. The decline and rehabilitation of the southeastern Alaska herring fishery. U.S. Fish Wildl. Serv., Fish. Leafl. 252, 13 p. Laevastu, T., and H. A. Larkins. 1981. Marine fisheries ecosystem. Fishing News Books Ltd., Farnham, Surrey, England, 162 p. Lear, W. 1970. Catch statistics, length and age composition of Greenland halibut in the Newfoundland area. Fish. Res. Board Can. Tech. Rep. 79, 27 p. -120- Levings, C. D. 1967. A comparison of the growth rates of the rock sole, Lep dopsetta bilineata Ayres, in northeast Pacific waters. Fish. Res. Board Can. Tech. Rep. 36, 43 p. Low, L., M. Alton, V. Wespestad, and E. Brown. 1979. Condition of groundfish resources in the Gulf of Alaska. Unpubl. manuscr., 43 p. Northwest and Alaska Fish. Cent., Natl. Mar. Fish. Serv., NOAA, 2725 Montlake Blvd. E., Seattle, WA 98112. (Submitted to Int. North Pac. Fish. Comm. by the U.S. Natl. Section.) Low, L., R. Bakkala, H. Larkins, S. Mizroch, V. Wespestad, and J. Akada. 1978. Information on groundfish resources in the Bering Sea and Aleutian Region. Unpubl. manuscr., 92 p. Northwest and Alaska Fish. Cent., Natl. May. Fish. Serv., NOAA, 2725 Montlake Blvd. E., Seattle, IVA 98112. (Submitted to Int. North Pac. Fish. Comm. by the U.S. Natl. Section.) Low., L. L., G. K. Tanonaka, and H. H. Shippen. 1976. Sablefish of the northeastern Pacific Ocean and Bering Sea. NWAFC Processed Rep., 115 p. Northwest and Alaska Fish Cent., Natl. Mar. Fish. Serv., NOAA, 272S Montlake Blvd. E., Seattle, WA 98112. Lubimova, T. G. 1963. Osnovnye cherty biologii raspredeleniya Tikhookeanskogo morskogo okunya (Sebastodes alutus Gilbert) v zalive Alyaska (Some essential features of the biology and distribution of Pacific ocean perch (Sebastodes alutus Gilbert) in the Gulf of Alaska). Tr. Vses. Nauchno-issled. Inst. Morsk. Rybn. Khoz. Okeanogr. 50):293-303. In Russian. (Transl. by Israel Program Sci. Transl., 1968, p. 308-318 in P. A. Moiseev (,editor), Soviet fisheries investigations in the northeast Pacific, Pt. 1, avail. U.S. Dep. Commer., Natl. Tech. Inf. Serv., Springfield, Va., as TT67-S1203.) Maeda, T. 1969. Studies on the trawl fishing grounds in Eastern Bering Sea - III. On the age and length composition of yellowfin sole. Bull. Jpn. Soc, Sci, Fish. 35(3):251-257. -121- Major, R. L., and H. H. Shippen. 1970. Synopsis of biological data on Pacific ocean perch, Sebastodes alutus. U.S. Fish Wildl. Serv., Circ. 347 (FAO Fish. Synopsis 79), 38 p. Mikawa, M. 1967. Ecology of the lesser halibut Reinhardtius hippoglossoides Maesurae Jordan and Snyder. Tahoku Reg. Fish. Lab. Bull. 23:1-41. In Japanese. (Fish. Res. Board Can., Transl. 1260, 106 p.). Moberly, S. A. 1974. Age, sex and size composition of Pacific herring (Clupea pallasii from southeastern Alaska during winter and spring, 1970-1971. Alaska Dep. Fish Game, Tech. Data Rep. 11, 20 p, Murai, S., H. Gangmark, and R. French. 1981. All nation removals of groundfish, herring, and shrimp from the Eastern Bering Sea and Northeast Pacific Ocean 1964-80. U.S. Dep. Commer., NOAA Tech. Memo. NMFS F/NWC-14, 40 p. (Avail. Natl. Tech. Inf. Serv., Springfield, VA as PB82-148693.) North Pacific Fishery Management Council. 1979. Bering-Chukchi Sea herring, draft fishery management plan. North Pac. Fish. Manage. Counc., P. 0. Box 31361, Anchorage, AK 99510. Paraketsov, I. A. 1963. Obiologii Sebastodes alutus Beringova morya (On the biology of Sebastodes alutus of the Bering Sea). Tr. Vses. Nauchno-issled. Inst. @brsk. Rybn. Khoz. .04 Okeanogr. 48 (Izv. Tikhookean. Nauchno-issled. Inst, Morsk. Rybn. Khoz. Okeanogr. SO):305-312. In Russian. (Transl. by Israel Program Sci. Transl., 1968, p. 319-327 in P. A. Moiseev (editor), Soviet fisheries investigations in the northeast Pacific, Pt, 1, avail. U.S. Dep. Comer., Natl. Tech. Inf. Serv., Springfield, VA., as TT67-51203.) -122- Pautov, G. B. 1972. Neketorye osobennosti biologii tikhookeanskogo morskogo okunia (Sebastodes alutus Gilbert) Beringova moria (Some characteristic features of the biology of the Pacific ocean perch (Sebastodes alutus Gilbert) in the Bering Sea). Izv. Tikhookean. Nauchno-issled. Inst. Morsk. Rybn. Khoz. Okeanogr. 81:91-117. (Transl. 1973, 62 p, Transl. Bur. Dep. Sec. State, Can., Transl. Ser. 2828.) Pereyra, W. T., J. E. Reeves, and R. G. Bakkala. 1976. Demersal fish and shellfish resources of the eastern Bering Sea in the baseline year 1975. Processed Rep., 619 p. Northwest and Alaska Fish. Cent., Natl, Mar. Fish. @ Serv. , NOAA, 2 7 2 5 Montlake Blvd. E. , Seattle, WA 98112. Reid, G. M. 1971a. Alaska's fishery resources, the Pacific herring (Qlupea pallasii Unpubl. rep., 20 p. Auke Bay Lab., Northwest and Alaska Fish. Cent., Natl. Mar. Fish. Serv., NOAA, P. 0. Box 155, Auke Bay, AK 99821. 1971b. Age composition, weight, length and sex of herring (Clupea pallasii used for reduction in Alaska, 1926-66. U.S. Dep. Commer., Spec. Sci. Rep.- Fish. 634, 25 p. Ronholt, L. L., H. H. Shippen, and E. S. Brown. 1978. Demersal fish and shellfish resources of the Gulf of Alaska from Cape Spencer to Unimak Pass 1948-1976 (a historical review). 4 Volumes. Unpubl. manuscr., various pagination. Northwest and Alaska Fish. Cent., Natl. Mar. Fish, Serv., NOAA, 2725 Montlake Blvd. E., Seattle, WA 98112. -123- Runyantsev, A. I. , and M. A. Darda. 1970. Letniaia seld vostochnoi chasti Beringova moria (Sumer herring in the eastern Bering Sea). Tr. Vses. Nauchno-issled. Inst. Morsk. Rybn. Khoz. Okeanogr. 70 (Izv. Tikhookean. Nauchno-issled. Inst. Rybn. Khoz. Okeanogr. 72):402-432. In Russian. (Transl. by Israel Program Sci. Transl., 1972, p. 409-441 in P. A. Moiseev (editor), Soviet fisheries investigations in the northeastern Pacific, Pt. S, avail. U.S. Dep. Commer., Natl. Tech. Inf. Serv., Springfield, VA., as TT71-50127.) Sasaki, T. 1978. Preliminary report on sablefish and Pacific coast stock by Hatsue Maru No. 55 in the Gulf of Alaska in the summer of 1978. Unpubl. manuscr., 31 p. Far Seas Fish. Res. Lab., Fish. Agency Jpn., 1000 Orido, Shimizu 424, Jpn. 1981. Trends in sablefish stocks in.the Aleutian Region and the Gulf of Alaska. Unpubl. manuscr.,34 p. Far Seas Fish. Res. 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Alaska Marine Environmental Assessment Project Forage Fish Spawning Surveys - Southern Bering Sea. Unpubl. manuscr., 104 p. Alaska-Dep. Fish Game, Comer. Fish. Div., P. 0. Box 686, Kodiak, Ak. Warner, L M., and P. M. Shafford. 1976. Forage fish spawning surveys, Unimak Pass to Ugashik River. In Environ- mental assessment of the Alaskan continental shelf, Quarterly Reports, July-Septenber 2:63-102. U.S. Dep. Commer., Natl. Oceanic Atmos. Admin., Off. Mar. Pollut. Assess., Boulder, Colo. -125- Webb, L. A.,and B. J. Lockner. 1974. Trap fishing black cod (Anaplopoma. fimbria) in British Columbia waters. Can. Dep. Environ., Fish. Mar. Serv., Ind. Dev. Branch Tech. Rep. Ser. 81, 70 p. Weber, D. D., and H. H. Shippen. 1975. Age-length-weight and distribution of Alaska plaice, rock soleY and yellowfin sole collected from the southeastern Bering Sea in 1961. Fish. Bull., U.S. 73(4):919-924. Wespestad, V. G., and L. H. Barton. 1979. Distribution and migration and status of Pacific herring. In Fisheries oceanography-eastern Bering Sea Shelf, NWAFC Processed Rep. 79-20, p. 166-212. Northwest and Alaska Fish. Cent., Natl. Mar. Fish. Serv., NOAA, 272S Montlake Blvd. E.) Seattle, WA 98112. Westerheim, S. J. 1977. Length-weight and length-girth relationships, maturity, spawning season, and diet of Pacific cod (@adus macrocephalus) collected in British Columbia waters during April 1975-February 1976. Fish. Res. Board Can. Manuscr. Rep. Ser. 1420, 68 p. Westerheim, S. J., and W. R. Harling. 1975. Age-length relationships for 26 scorpaenids in the northeast Pacific Ocean. Can. Dep. Environ., Fish. Mar. Serv., Res. Dev. Tech. Rep. 565, 12 p. DATE DUE 3AYLORDINO. 2333 PRINTED N U S A 3 6668 14106 8793