The Bering Sea Ecosystem -- Copyright -- Preface -- Contents -- Executive Summary -- CHANGES IN THE BERING SEA ECOSYSTEM -- CAUSE AND EFFECT IN THE BERING SEA: THE CASCADE HYPOTHESIS -- DIFFICULTIES IN OBTAINING INFORMATION -- RECOMMENDATIONS -- Research Recommendations -- Management and Institutional Recommendations -- Recommendation to Reverse Declines in Marine Mammals and Birds -- THE FUTURE -- 1 Introduction -- THE PROBLEM -- THIS STUDY -- 2 Marine Ecosystems: A Conceptual Framework -- CONCEPTUAL FRAMEWORK -- Ecosystems and the Concept of Order -- Cascading Trophic Interactions in Ecosystems -- The Effects of Climate on Structuring Marine Ecosystems -- Summary -- OCEANIC AND TERRESTRIAL ECOSYSTEMS -- ENVIRONMENTAL AND ANTHROPOGENIC EFFECTS -- THE CONDITION OF AN ECOSYSTEM -- ECOSYSTEM MANAGEMENT -- THE BERING SEA ECOSYSTEM AND ITS ANALOGS -- DELINEATION OF THE BERING SEA ECOSYSTEM -- 3 The Bering Sea Ecosystem: Geology, Physics, Chemistry, and Biology of Lower Trophic Levels -- MARINE GEOLOGY -- Sediments -- Coastal Geography -- PHYSICAL OCEANOGRAPHIC STRUCTURE -- Physical Characteristics and Bathymetry of the Northern North Pacific and Bering Sea -- The Basins -- Gulf of Alaska Circulation -- Bering Sea Circulation and Hydrographic Structure -- Sea Ice -- Marine Chemistry of the North Pacific and Bering Sea -- Sources and Magnitude of Variability -- Atmospheric Forcing and Ocean Circulation -- Ocean Temperature -- Ice -- Summary -- PRIMARY AND SECONDARY PRODUCTION -- Water Column Primary Production -- Continental Shelf -- Basin -- Shelf Break -- Aleutian Island Arc -- Water Column Secondary Production -- Sources and Magnitude of Variability -- BIOLOGY OF LOWER TROPHIC LEVELS -- Benthic Production -- Sources and Magnitude of Variability -- 4 Biology of Higher Trophic Levels -- INVERTEBRATES -- Life History and Distribution.

Squid (Berryteuthis sp. and Gonatus sp.) -- King Crab (Paralithodes spp. and Lithodes sp.) -- Tanner Crab (Chionoecetes spp.) -- Hair Crab (Erimacrus Isenbeckii) -- Shrimp (Family Pandalidae) -- Scallops (Family Pectinidae) -- FINFISH -- Life History, Distribution, and Variability -- Walleye Pollock (Theragra chalcogramma) -- Pacific Cod (Gadus macrocephalus) -- Sablefish (Anoplopoma fimbria) -- Atka Mackerel (Pleurogrammus monopterygius) -- Yellowfin Sole (Limanda aspera) -- Greenland Turbot (Reinhardtius hippoglossoides) -- Pacific Halibut (Hippoglossus stenolepis) -- Other Flatfishes (Family Pleuronectidae) -- Pacific Ocean Perch (Sebastes alutus) -- Other Rockfishes (Family Scorpaenidae) -- Pacific Herring (Clupea harengus pallasi) -- Pacific Sand Lance (Ammodytes Hexapterus) -- Capelin (Mallotus villosus) -- Pacific Salmon (Oncorhynchus spp.) -- BIRDS -- Life History and Distribution -- Sources and Magnitude of Variability -- Prey Availability -- Productivity -- Die-Offs -- Abundance -- Introduced Mammals -- Gill Net Mortality -- Consumption of Plastic Particles -- Oiling -- Hunting -- MARINE MAMMALS -- Life History and Distribution -- Steller Sea Lion -- Northern Fur Seal -- Harbor Seal -- Baleen Whales -- DISCUSSION OF POPULATION DECLINES -- Disease -- Pollution -- Entanglements -- Human Disturbance and Takings -- Predation -- Direct Climate Effects on Survival -- Life History Patterns -- Food -- Fishery Effects on Pinniped Foods -- Diets and Food Limitation -- Other Evidence of Food Limitation -- Northern Fur Seals -- Steller Sea Lions -- Harbor Seals -- 5 Human Use-Fisheries -- FISH AND INVERTEBRATES -- Eastern Bering Sea, Aleutian Islands, and Aleutian Basin -- Finfish -- Invertebrates -- General Management Issues -- Western Bering Sea -- Finfish -- Summary (Pelagic Fish Community). -- Demersal Communities. -- Invertebrates.

MARINE MAMMALS (AND BIRDS) -- Management Systems -- INTERACTIONS OF INDIGENOUS POPULATIONS WITH MARINE ECOSYSTEMS -- Russia -- United States-Alaska -- Accounts of Harvesting by Species and Species-Groups -- Steller Sea Lion -- Northern Fur Seal -- Harbor Seal -- Ice-Associated Seals -- Walrus -- Sea Otter -- Whales -- 6 Causes and Effects in the Bering Sea Ecosystem -- ENVIRONMENTAL VARIABILITY -- Natural Frequencies in the Environment -- Environmental Effects on Marine Mammals and Birds -- Bering Sea Fish (Invertebrates) and Fisheries -- HUMAN EFFECTS -- Pollution -- Offshore Oil and Gas Development -- Direct Effects of Extractive Resource Use -- Indirect Effects of Extractive Resource Use -- THE "CASCADE HYPOTHESIS" AND THE BERING SEA ECOSYSTEM -- Marine Mammals -- Seabirds -- Fish and Invertebrates -- DISCUSSION -- CONCLUSIONS -- 7 Implications for Management Policy and Institutional Arrangements -- THE BERING SEA ECOSYSTEM AS AN ASSET -- Management Policy and Wise Use of the Ecological Asset -- IMPLICATIONS FOR MANAGEMENT -- 8 Gaps in Knowledge and Recommendations -- RECOMMENDATIONS -- Research -- Adaptive Management -- Research to Improve Understanding of the Ecosystem -- Management and Institutional Recommendations -- Institutions -- Specific Action to Reverse Declines in Marine Mammals and Birds -- THE FUTURE -- References -- Appendix A Biographical Sketches of the Committee Members -- Appendix B Organizations and Individuals that Provided Information to the Committee -- WORKSHOP SEPTEMBER 22-24, 1994 ANCHORAGE, ALASKA -- WORKSHOP DECEMBER 1-3, 1993 SEATTLE, WASHINGTON -- ADDITIONAL PARTICIPANTS -- SPONSORS.