CONTENTS

		
	LIST OF FIGURES	

	LIST OF TABLES
	
	EXECUTIVE SUMMARY
		Pacific Herring DPS Delineation	
		Pacific Herring BRT Risk Conclusions
		Consideration of the Puget Sound Ecosystem

	ACKNOWLEDGEMENTS	

	INTRODUCTION	
		Scope and Intent of Present Document	
		Key Questions in ESA Evaluations
			The "Species" Question
			The "Extinction Risk" Question	
		Summary of Information Presented by the Petitioner	
			Stock Structure	
			Risk of Extinction	

	BACKGROUND	
		Environmental History and Features of Puget Sound	
			Introduction	
			Geological and Climatic History	
			Oceanographic and Geomorphological Features	
				Northern Puget Sound
				Main Basin
				Whidbey Basin
				Southern Puget Sound
				Hood Canal			
			Marine Species in Puget Sound 	
		Environmental Features of the Strait of Georgia
		Pacific Herring	
			General Biology	
				Geographical distribution and migrations	
				Reproduction and development	
				Trophic interactions	
				Growth and age distributions	
		Marine Zoogeographic Provinces	

	APPROACHES TO THE SPECIES QUESTION 	
		The "Species" Question	
			Habitat Characteristics	
			Phenotypic and Life-History Traits	
			Mark/Recapture Studies
			Morphological Differentiation
			Genetic Differentiation
			Relationship of DPS and Stock Concepts		
		Pacific Herring DPS Information	
			Phenetic and Genetic Information Relating to the Species Question	
				Genetic information	
				Life-History information	
				Spawning location and spawn timing	
				Tagging and distribution	
				Seasonal migration	
				Larval retention areas
				Parasite incidence
				Growth rate, body size-at-age, and age structure
				Age at maturity
				Fecundity
				Morphological differentiation	
			Herring Stock Discreteness and the Metapopulation Concept	
		Pacific Herring DPS Delineation	
				
	APPROACHES TO EVALUATING RISK OF EXTINCTION	
		The "Extinction Risk" Question	
			Absolute Numbers	
			Historical Abundances and Carrying Capacity	
			Trends in Abundance	
			Factors Influencing Abundance	
			Threats to Genetic Integrity
			Climate Variability	
		Risk-Assessment Methods	
		Risk Factors	
			Overharvesting	
			Predation	
			Climate
			Habitat	
			Effects of Pollution	
				Pollution in Georgia Basin DPS spawning sites	
				Region-wide status and long-term trends in pollution	
			Summary of Risk Factors	
		Pacific Herring Abundance and Productivity	
			Abundance and Trends	
				Abundance		
				Quantitative trend analysis	
			Trends in Productivity 	
			Risk Conclusions
		Summary of Risk Assessment	

	CITATIONS
		
	GLOSSARY	

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