1 North Pacific Research Board Project Final Report
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1 1 NORTH PACIFIC RESEARCH BOARD PROJECT FINAL REPORT 2 3 4 5 Seasonal Bioenergetics of Pollock, Cod and Arrowtooth Flounder in the Bering Sea 6 7 8 NPRB Project B54 Final Report 9 10 11 Ron Heintz 12 13 14 Recruitment Energetics and Coastal Assessment Program, Alaska Fisheries Science 15 Center, National Marine Fisheries Service, NOAA, Auke Bay Laboratories, Juneau, AK, 16 99801, USA 17 September 2009 2 1 2 Abstract: 3 4 The NPRB funded Bering Sea Integrated Ecosystem Research Program (BSIERP) and NSF funded 5 Bering Ecosystem Study (BEST) provided an unparalleled opportunity to understand how the 6 Bering Sea ecosystem supports the production of commercially valuable species. The seasonal 7 bioenergentics component evaluated the condition of juvenile fish at different ontogenetic 8 stages in an effort to understand the effect of environmental variability on the health of fish 9 populations. The intent was to increase our understanding of the mechanisms underlying 10 recruitment variability in the southeastern Bering Sea so that fishery managers could gain the 11 ability to understand how climate and fishing influence the variability in harvestable biomass. 12 Specifically, the dry mass, lipid, energy density and growth of juvenile gadids and arrowtooth 13 flounder were measured on specimens collected on a series of surveys conducted between May 14 of 2008 and October of 2010. Over 3500 separate analyses were conducted on larvae, young-of- 15 the-year, age-1 juveniles and their zooplankton prey. The results of these analyses were 16 integrated into other findings from the BEST/BSIERP Program to evaluate the health of fish 17 populations under different environmental conditions during different developmental stages. 18 The principle findings of the work are: 19 1. Walleye pollock have a relatively short time window for provisioning themselves with lipid 20 prior to winter after they complete larval development. 21 2. Climatic conditions mediate their ability to provision themselves by influencing the spatial 22 match between young-of-the-year pollock and their prey and the quality of those prey. 23 3. Fish that surpass a critical energy content during this period have the highest probability of 24 surviving winter. This critical level depends on acquiring both a large size and high energy 25 density. 26 4. A mechanistic connection between climate and recruitment has been identified that 27 indicates that under so-called cool conditions in the Bering Sea, high-lipid prey are available 28 to juvenile pollock in fall in sufficient abundance to support rapid growth and energy 29 storage. When these conditions do not exist, recruitment can be expected to be below 30 average. 31 5. Similar results have been found for Pacific cod 32 3 1 2 Key Words: 3 pollock, Pacific cod, arrowthooth flounder, juvenile, larvae, energy, lipid, condition, recruitment 4 5 Citation : 6 Heintz, R. (2014) Seasonal Bioenergetics of Pollock, Cod and Arrowtooth Flounder in the 7 Bering Sea. NPRB Final report for project B54. 8 4 1 2 Table of Contents 3 Contents 4 Abstract: .................................................................................................................... 2 5 Key Words: ................................................................................................................. 3 6 Citation : .................................................................................................................... 3 7 Table of Contents ....................................................................................................... 4 8 Study Chronology: ...................................................................................................... 9 9 Introduction ............................................................................................................... 9 10 Overall Objectives: ................................................................................................... 10 11 Chapter 1 - The Effect of Temperature and Nutrition on RNA/DNA Ratio and Growth of 12 Pacific Cod (Gadus macrocephalus) and Walleye Pollock (Theragra chalcogramma) 13 Larvae ...................................................................................................................... 13 14 1.1 Abstract: .................................................................................................................. 13 15 1.2 Introduction ............................................................................................................. 14 16 1.3 Materials and Methods ........................................................................................... 17 17 1.3.1 Pacific Cod Temperature Experiment ............................................................... 18 18 1.3.2 Pacific Cod Starvation Experiment ................................................................... 19 19 1.3.3 Walleye Pollock Temperature Experiment ....................................................... 20 20 1.3.4 Biochemical Analyses ....................................................................................... 20 21 1.3.5 Statistical Analyses: .......................................................................................... 21 22 1.3.5.1 Pacific Cod Temperature Experiment ............................................................ 22 23 1.3.5.2 Pacific Cod Starvation Experiment ................................................................ 22 24 1.3.5.3 Pacific Cod Growth Model ............................................................................. 23 25 1.3.5.4 Walleye Pollock Temperature Experiment .................................................... 24 26 1.4 Results ..................................................................................................................... 24 27 1.4.1 Pacific Cod Temperature Experiment .................................................................. 24 28 1.4.2 Pacific Cod Starvation Experiment ....................................................................... 25 29 1.4.3 Pacific Cod Growth Model Synthesis ................................................................... 26 30 1.4.4 Walleye Pollock Temperature Experiment .......................................................... 26 31 1.5 Discussion ................................................................................................................ 26 5 1 1.6 Conclusion ............................................................................................................... 32 2 1.7 Acknowledgements ................................................................................................. 33 3 1.8 Literature Cited ....................................................................................................... 33 4 1.9 Figures and Tables .............................................................................................. 46 5 Figure. 1.4a,b ............................................................................................................. 49 6 Chapter 2 - Conceptual model of energy allocation in walleye pollock (Theragra 7 chalcogramma) from larvae to age-1 in the southeastern Bering Sea ........................ 56 8 2.1 Abstract ................................................................................................................... 56 9 2.2 Keywords: ................................................................................................................ 57 10 2.3 Introduction ............................................................................................................. 57 11 2.3.1 Study region ...................................................................................................... 60 12 2.4 Materials and methods .......................................................................................... 61 13 2.4.1. Biological sampling .......................................................................................... 61 14 2.4.2. Chemical Analysis ............................................................................................ 63 15 2.4.3. Statistical analysis ............................................................................................ 66 16 2.5. Results .................................................................................................................... 69 17 2.5.1. Biological sampling .......................................................................................... 69 18 2.5.2. Cohort-specific patterns from age-0 to age- ................................................... 69 19 2.5.3. Seasonal patterns in energy allocation of age-0 fish ...................................... 70 20 2.5.4. Seasonal patterns in length of age-0 fish ........................................................ 71 21 2.6 Discussion ............................................................................................................... 71 22 2.7 Acknowledgements ................................................................................................. 75 23 2.8 References ............................................................................................................... 76 24 2.9 Table legends ........................................................................................................... 84 25 2.10 Figure legends ....................................................................................................... 85 26 Chapter 3 - Correlation between recruitment and fall condition of age-0 pollock 27 (Theragra