Steller Sea Lions and Fisheries: Competition at Sea?
نویسندگان
چکیده
.................................................................................................................................. ii PREFACE ..................................................................................................................................... iii TABLE OF CONTENTS ............................................................................................................ iv LIST OF FIGURES .................................................................................................................... vii LIST OF ABBREVIATIONS ................................................................................................... viii ACKNOWLEDGEMENTS ........................................................................................................ ix DEDICATION............................................................................................................................... x CHAPTER 1: GENERAL INTRODUCTION ........................................................................... 1 1.1 Competition between marine mammals and fisheries .......................................................... 1 1.2 Decline of the Steller sea lion ............................................................................................... 2 1.3 Steller sea lion biology ......................................................................................................... 7 1.3.1 Diet and foraging behaviour .......................................................................................... 8 1.3.2 Dispersal patterns and population trends ..................................................................... 10 1.3.3 Proximate causes of the decline ................................................................................... 11 1.4 Fisheries in western Alaska ................................................................................................ 13 1.4.1 Walleye pollock ........................................................................................................... 15 1.4.2 Pacific cod .................................................................................................................... 18 1.4.3 Atka mackerel .............................................................................................................. 20 1.4.4 Fisheries management .................................................................................................. 22 1.5 Thesis aims and objectives ................................................................................................. 23 1.6 Thesis structure ................................................................................................................... 24 CHAPTER 2: STELLER SEA LIONS AND FISHERIES: COMPETITION AT SEA? .... 25 2.
منابع مشابه
Supplemental Environmental Impact Statement
The Gulf of Alaska and Bering Sea Aleutian Islands groundfish fisheries have been managed under fishery management plans since 1978 and 1981, respectively. The range of the Steller sea lion overlaps the waters where the fisheries are conducted. Under the Endangered Species Act, Steller sea lion west of Cape Suckling, Alaska, are listed as endangered; east of Cape Suckling they are listed as thr...
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Over the past three decades, the decline and altered spatial distribution of the western stock of Steller sea lions (Eumetopias jubatus) in Alaska have been attributed to changes in the distribution or abundance of their prey due to the cumulative effects of fisheries and environmental perturbations. During this period, dietary prey occurrence and diet diversity were related to population decli...
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Learning about ecosystem processes and patterns is an essential component of Ecosystem Based Fishery Management and the sustainable use of natural resources. Currently, such learning is usually done through adaptive management (passive or active) or Management Strategy Evaluation, which are explained. An example of adaptive management in northwestern Australia shows the strengths and limitation...
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