73 research outputs found

    Interrelationships of Pacific herring, Clupea pallasi, populations and their relation to large-scale environmental and oceanographic variables

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    Thesis (Ph.D.) University of Alaska Fairbanks, 1999Recruitment estimates for Pacific herring, Clupea pallasi, populations in the Bering Sea and Northeast Pacific Ocean are highly variable, difficult to forecast, and crucial for determining optimum harvest levels. Age-structured population models for annual stock assessments of the sac-roe fisheries rely on fishery and survey age composition data tuned to an auxiliary survey of total biomass. In Chapter 1, the first age-structured model for Norton Sound herring was developed similarly to existing models. Estimates of variability from age-structured stock assessment models for Pacific herring are often not calculated. In Chapter 2, a parametric bootstrap procedure using a fit of the Dirichlet distribution to observed age composition data was developed as a quick and easy method for computing error estimates of model estimates. This bootstrap technique was able to capture variability beyond that of the multinomial distribution. This technique can provide estimates of variability for existing population models with age composition data requiring little change to the original model structure. Recruitment time series from Pacific herring stock assessment models for 14 populations in the Bering Sea and Northeast Pacific Ocean were analyzed for links to the environment. For some populations, recruitment series were extended backward in time using cohort analysis. In chapter 3, correlation and multivariate cluster analyses were applied to determine herring population associations. There appear to be four major herring groups: Bering Sea, outer Gulf of Alaska, coastal SE Alaska, and British Columbia. These associations were combined with an exploratory correlation analysis of environmental data in chapter 4. Appropriate time periods for environmental variables were determined for use in Ricker type environmentally dependent spawner-recruit forecasting models. Global and local scale environmental variables were examined in forecasting models, resulting in improvements in recruitment forecasts compared to models without environmental data. The exploratory correlation analysis and best fit models, determined by jackknife error prediction, indicated temperature data corresponding to the year of spawning resulted in the best forecasting models. The Norton Sound age-structured model, parametric bootstrap procedure, and recruitment forecasting models serve as enhancements to the decision process of managing Pacific herring fisheries

    PICES-GLOBEC International Program on Climate Change and Carrying Capacity: Report of 2001 BASS/MODEL, MONITOR and REX Workshops, and the 2002 MODEL/REX Workshop

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    Table of Contents [pdf, 0.22 Mb] Executive Summary [pdf, 0.31 Mb] Report of the 2001 BASS/MODEL Workshop [pdf, 0.65 Mb] To review ecosystem models for the subarctic gyres Report of the 2001 MONITOR Workshop [pdf, 0.7 Mb] To review ecosystem models for the subarctic gyres Workshop presentations: Sonia D. Batten PICES Continuous Plankton Recorder pilot project Phillip R. Mundy GEM (Exxon Valdez Oil Spill Trustee Council`s "Gulf Ecosystem Monitoring" initiative) and U.S. GOOS plans in the North Pacific Ron McLaren and Brian O`Donnell A proposal for a North Pacific Action group of the international Data Buoy Cooperation Panel Gilberto Gaxiola-Castrol and Sila Najera-Martinez The Mexican oceanographic North Pacific program: IMECOCAL Sydney Levitus Building global ocean profile and plankton databases for scientific research Report of the 2001 REX Workshop [pdf, 1.73 Mb] On temporal variations in size-at-age for fish species in coastal areas around the Pacific Rim Workshop presentations: Brian J. Pyper, Randall M. Peterman, Michael F. Lapointe and Carl J. Walters [pdf, 0.33 Mb] Spatial patterns of covariation in size-at-age of British Columbia and Alaska sockeye salmon stocks and effects of abundance and ocean temperature R. Bruce MacFarlane, Steven Ralston, Chantell Royer and Elizabeth C. Norton [pdf, 0.4 Mb] Influences of the 1997-1998 El Niño and 1999 La Niña on juvenile Chinook salmon in the Gulf of the Farallones Olga S. Temnykh and Sergey L. Marchenko [pdf, 0.5 Mb] Variability of the pink salmon sizes in relation with abundance of Okhotsk Sea stocks Ludmila A. Chernoivanova, Alexander N. Vdoven and D.V. Antonenko [pdf, 0.3 Mb] The characteristic growth rate of herring in Peter the Great Bay (Japan/East Sea) Nikolay I. Naumenko [pdf, 0.5 Mb] Temporal variations in size-at-age of the western Bering Sea herring Evelyn D. Brown [pdf, 0.45 Mb] Effects of climate on Pacific herring, Clupea pallasii, in the northern Gulf of Alaska and Prince William Sound, Alaska Jake Schweigert, Fritz Funk, Ken Oda and Tom Moore [pdf, 0.6 Mb] Herring size-at-age variation in the North Pacific Ron W. Tanasichuk [pdf, 0.3 Mb] Implications of variation in euphausiid productivity for the growth, production and resilience of Pacific herring (Clupea pallasi) from the southwest coast of Vancouver Island Chikako Watanabe, Ahihiko Yatsu and Yoshiro Watanabe [pdf, 0.3 Mb] Changes in growth with fluctuation of chub mackerel abundance in the Pacific waters off central Japan from 1970 to 1997 Yoshiro Watanabe, Yoshiaki Hiyama, Chikako Watanabe and Shiro Takayana [pdf, 0.35 Mb] Inter-decadal fluctuations in length-at-age of Hokkaido-Sakhalin herring and Japanese sardine in the Sea of Japan Pavel A. Balykin and Alexander V. Buslov [pdf, 0.4 Mb] Long-term variability in length of walley pollock in the western Bering Sea and east Kamchtka Alexander A. Bonk [pdf, 0.4 Mb] Effect of population abundance increase on herring distribution in the western Bering Sea Sergey N. Tarasyuk [pdf, 0.4 Mb] Survival of yellowfin sole (Limanda aspera Pallas) in the northern part of the Tatar Strait (Sea of Japan) during the second half of the 20th century Report of the 2002 MODEL/REX Workshop [pdf, 1.2 Mb] To develop a marine ecosystem model of the North Pacific Ocean including pelagic fishes Summary and Overview [pdf, 0.4 Mb] Workshop presentations: Bernard A. Megrey, Kenny Rose, Francisco E. Werner, Robert A. Klumb and Douglas E. Hay [pdf, 0.47 Mb] A generalized fish bioenergetics/biomass model with an application to Pacific herring Robert A. Klumb [pdf, 0.34 Mb] Review of Clupeid biology with emphasis on energetics Douglas E. Hay [pdf, 0.47 Mb] Reflections of factors affecting size-at-age and strong year classes of herring in the North Pacific Shin-ichi Ito, Yutaka Kurita, Yoshioki Oozeki, Satoshi Suyama, Hiroya Sugisaki and Yongjin Tian [pdf, 0.34 Mb] Review for Pacific saury (Cololabis saira) study under the VENFISH project lexander V. Leonov and Gennady A. Kantakov [pdf, 0.34 Mb] Formalization of interactions between chemical and biological compartments in the mathematical model describing the transformation of nitrogen, phosphorus, silicon and carbon compounds Herring group report and model results [pdf, 0.34 Mb] Saury group report and model results [pdf, 0.46 Mb] Model experiments and hypotheses Recommendations [pdf, 0.4 Mb] Achievements and future steps Acknowledgements [pdf, 0.29 Mb] References [pdf, 0.32 Mb] Appendix 1. List of Participants [pdf, 0.32 Mb] Appendices 2-5. FORTRAN codes [pdf, 0.4 Mb] (Document pdf contains 182 pages

    Stock structure and environmental effects on year class formation and population trends of Pacific herring, Clupea pallasi, in Prince William Sound, Alaska

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    Thesis (Ph.D.) University of Alaska Fairbanks, 2003Fluctuating forage fish populations trigger large ecosystem responses in the North Pacific. A representative species, Pacific herring, Clupea pallasi, was chosen to model environmental effects on population fluctuations and recruitment with a case example in Prince William Sound (PWS), Alaska. A unique approach was used to 1) develop a spatially-explicit, life history-based conceptual stock model, 2) quantify population level effects of climatic trends, and 3) model key environmental factors affecting recruitment. Framed as a simulation model, the stock model was compartmentalized by life-history stages based on shared habitats and environmental forcing. Initial model conditions impacting year-class formation were adult size-at-age, spawn timing, location and spawner density, and conditions during egg incubation, all impacting a two-stage larval mortality rate. Larval survival probably dictates the extremes in year-class strength. Age-1 abundance should reflect recruitment levels 2-3 yrs later, unless a predator pit exists. A metapopulation structure was proposed with at least two local population groupings with spatial complexity required to maintain stock levels. Herring abundance correlated with long-term climate trends supporting hypotheses of bottom up environmental forcing. Adult growth was oscillatory over a 13 yr period in phase with zooplankton production and climatic trends. Spawn timing occurred progressively earlier over the last 30 yr period with a concurrent regional spawn allocation shift and decrease in recruits per spawner. Incorporating local stock structure and local environmental variables into nonlinear herring recruitment models improved explanatory power over traditional models. Best-fit variables were eastern PWS SST, salinity, SST variance, and salinity variance from spring to fall. Eight critical life stage periods were defined based on the season and lag of the best-fitting varibles. Examining other variables in these critical periods led to defining potential key processes affecting year class formation. Allocation of spawn and age-3 recruits to metapopulation regions also impacted recruitment to PWS as a whole and these results supported the metapopulation theory. The results led to formulation of a new theory, entitled 'opposing response', explaining the mechanism producing the observed pattern of alternating strong and week year class strengths in northern Pacific herring

    PICES-GLOBEC International Program on Climate Change and Carrying Capacity: Summary of the 1998 MODEL, MONITOR and REX Workshops, and Task Team Reports.

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    This volume summarizes the results of three workshops organized by the PICES-GLOBEC Climate Change and Carrying Capacity Program that were held just prior to the PICES Seventh Annual Meeting in Fairbanks, Alaska, in October 1998. These workshops represent the efforts of the REX, MODEL, and MONITOR Task Teams to integrate the results of national GLOBEC and GLOBEC-like programs to arrive at a better understanding of the ways in which climate change affects North Pacific ecosystems. (PDF contains 91 pages

    PICES-GLOBEC International Program on Climate Change and Carrying Capacity: Report of the 1999 MONITOR and REX Workshops, and the 2000 MODEL Workshop on Lower Trophic Level Modelling

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    Table of Contents [pdf, 0.11 Mb] Executive Summary [pdf, 0.07 Mb] MODEL Task Team Workshop Report Final Report of the International Workshop to Develop a Prototype Lower Trophic Level Ecosystem Model for Comparison of Different Marine Ecosystems in the North Pacific [pdf, 11.64 Mb] Report of the 1999 MONITOR Task Team Workshop [pdf, 0.32 Mb] Report of the 1999 REX Task Team Workshop Herring and Euphausiid population dynamics Douglas E. Hay and Bruce McCarter Spatial, temporal and life-stage variation in herring diets in British Columbia [pdf, 0.10 Mb] Augustus J. Paul and J. M. Paul Over winter changes in herring from Prince William Sound, Alaska [pdf, 0.08 Mb] N. G. Chupisheva Qualitative texture characteristic of herring (Clupea pallasi pallasi) pre-larvae developed from the natural and artificial spawning-grounds in Severnaya Bay (Peter the Great Bay) [pdf, 0.07 Mb] Gordon A. McFarlane, Richard J. Beamish and Jake SchweigertPacific herring: Common factors have opposite impacts in adjacent ecosystems [pdf, 0.15 Mb] Tokimasa Kobayashi, Keizou Yabuki, Masayoshi Sasaki and Jun-Ichi Kodama Long-term fluctuation of the catch of Pacific herring in Northern Japan [pdf, 0.39 Mb] Jacqueline M. O’Connell Holocene fish remains from Saanich Inlet, British Columbia, Canada [pdf, 0.40 Mb] Elsa R. Ivshina and Irina Y. Bragina On relationship between crustacean zooplankton (Euphausiidae and Copepods) and Sakhalin-Hokkaido herring (Tatar Strait, Sea of Japan) [pdf, 0.14 Mb] Stein Kaartvbeedt Fish predation on krill and krill antipredator behaviour [pdf, 0.08 Mb] Nikolai I. Naumenko Euphausiids and western Bering Sea herring feeding [pdf, 0.07 Mb] David M. Checkley, Jr. Interactions Between Fish and Euphausiids and Potential Relations to Climate and Recruitment [pdf, 0.08 Mb] Vladimir I. Radchenko and Elena P. Dulepova Shall we expect the Korf-Karaginsky herring migrations into the offshore western Bering Sea? [pdf, 0.75 Mb] Young Shil Kang Euphausiids in the Korean waters and its relationship with major fish resources [pdf, 0.29 Mb] William T. Peterson, Leah Feinberg and Julie Keister Ecological Zonation of euphausiids off central Oregon [pdf, 0.11 Mb] Scott M. Rumsey Environmentally forced variability in larval development and stage-structure: Implications for the recruitment of Euphausia pacifica (Hansen) in the Southern California Bight [pdf, 3.26 Mb] Scott M. Rumsey Inverse modelling of developmental parameters in Euphausia pacifica: The relative importance of spawning history and environmental forcing to larval stage-frequency distributions [pdf, 98.79 Mb] Michio J. Kishi, Hitoshi Motono & Kohji Asahi An ecosystem model with zooplankton vertical migration focused on Oyashio region [pdf, 33.32 Mb] PICES-GLOBEC Implementation Panel on Climate Change and Carrying Capacity Program Executive Committee and Task Team List [pdf, 0.05 Mb] (Document pdf contains 142 pages

    Coastal Pelagic Fishes (Report of Working Group 3); Subarctic Gyre (Report of Working Group 6)

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    This is a report of PICES Working Group 3 (Coastal Pelagic Fishes) for 1993 and the first Annual Report of the Subarctic Gyre Working Group (WG-6). (PDF contains 131 pages

    Year class variations as determined from pre-recruit investigations

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    PART II :: Proceedings from the second workshop under the cooperative programme of fisheries research between the institutions in Seattle, Nanaimo and Bergen, held in Bergen 28. - 30. September 1988. Compiled by Svein Sundby

    PICES-GLOBEC International Program On Climate Change And Carrying Capacity: Report of the 2000 BASS, MODEL, MONITOR and REX workshops, and the 2001 BASS/MODEL workshop

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    Table of Contents [pdf, 0.07 Mb] Executive Summary [pdf, 0.05 Mb] Report of the 2000 BASS Workshop on The Development of a conceptual model of the Subarctic Pacific basin ecosystems [pdf, 0.71 Mb] Report of the 2000 MODEL Workshop on Strategies for coupling higher and lower trophic level marine ecosystem models [pdf, 3.62 Mb] Report of the 2000 MONITOR Workshop on Progress in monitoring the North Pacific [pdf, 1.21 Mb] Report of the 2000 REX Workshop on Trends in herring populations and trophodynamics [pdf, 4.22 Mb] Report of the 2001 BASS/MODEL Workshop on Higher trophic level modeling [pdf, 0.29 Mb] (Document pdf contains 119 pages

    Threshold management strategies for exploited fish populations

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    Thesis (Ph.D.) University of Alaska Fairbanks, 1994Under a threshold management strategy, harvesting occurs at a constant rate but ceases when a population drops below a threshold. The threshold approach seeks to enhance long-term yield of a population and to maintain population renewability. I evaluated threshold management strategies for selected herring and pollock stocks in Alaska. First, I examined stock-recruitment data from 19 major herring stocks worldwide to provide the basis for evaluating threshold management strategies. Seventy-three percent of these stocks exhibited statistically significant density-dependence. Most stocks have compensatory, dome-shaped stock-recruitment curves. Then, I simulated threshold management strategies for eastern Bering Sea (EBS) pollock and herring and Prince William Sound (PWS) herring using a single-species model. I further examined seven alternative threshold estimation methods. Cohort analysis, catch-at-age analysis, and catch and population sampling yielded estimates of population parameters. The objective function was a weighted function of increased average yield and decreased standard deviation of yield over a planning horizon. Compared to a non-threshold approach, threshold management strategies increase the long-term average yields, stabilize population abundances, shorten rebuilding times, and increase management flexibility. For a maximum yield criterion and Ricker stock-recruitment models, optimal fishing mortalities are slightly above fishing mortalities at maximum sustained yield (MSY), and optimal threshold levels range from 40% to 60% of pristine biomass for EBS pollock, from 40% to 50% for EBS herring and from 30% to 60% for PWS herring. With fishing mortality at MSY and the criterion of equal trade-off between yield and its variation, optimal thresholds range from 20% to 30% of pristine biomass for pollock. With the status quo exploitation rate of 20%, optimal thresholds range from 10% to 25% of pristine biomass for EBS herring, and from 5% to 25% for PWS herring. Of the threshold estimation methods evaluated, default percentage of pristine biomass usually performs best. Loss of yield due to errors in threshold estimation is small, generally under 10%. A bout 15 to 20 years of data are required to obtain a reliable estimate of thresholds. With single-species dynamics, the form of the stock-recruitment curve, exploitation rate and management objective are the most important factors affecting optimal thresholds

    Pacific Hake, Merluccius productus, Autecology: A Timely Review

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    Pacific hake, Merluccius productus, the most abundant groundfish in the California Current Large Marine Ecosystem (CCLME), is a species of both commercial significance, supporting a large international fishery, and ecological importance, connecting other species as both predator and prey. Coastal Pacific hake migrations are characterized by movements between northern summer feeding areas and southern winter spawning areas, with variations in annual abundance, distribution, and the extent of these movements associated with varying climate-ocean conditions. In general, warm (cool) years with enhanced (reduced) stratification and poleward (equatorward) transport are often related to good (poor) recruitment, increased (decreased) northward distribution, and reduced (enhanced) growth. However, the classic periodic pattern of annual migration and distribution may no longer be fully representative. Based on recent advances in the understanding of climate-ocean variability off the U.S. west coast, we hypothesize that the annual movements of Pacific hake are more responsive to climate-ocean variability than previously thought, and further, that changes observed in Pacific hake distributions may reflect long-term changes in climate-ocean conditions in the CCLME. Therefore, an updated model of these relations is key to effective monitoring and management of this stock, as well as to devising scenarios of future change in the CCLME as a result of climate variations. The current state of knowledge of the relationship between the Pacific hake and its environment is reviewed, highlighting emerging ideas compared to those of the past, and priorities for future research are suggested
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