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What caused the Sacramento River fall Chinook stock collapse?

In this paper, we propose an interpretation of these events in which the prospect of a New Economy plays a key role in generating the other events. More specifically, we show that the mere prospect of high future productiv- ity growth can generate sizable gains in current productivity, as well as an economic expansion, a stock market boom and a financing boom for new firms. There are two main ingredients to our story: financing constraints due to limited contract enforceability and firm-level diminishing returns to scale. Financing constraints generate an endogenous size distribution for firms. Diminishing returns make aggregate productivity dependent on the size distribution of firms. In particular,. | What caused the Sacramento River fall Chinook stock collapse S. T. Lindley C. B. Grimes M. S. Mohr W. Peterson J. Stein J. T. Anderson L. W. Botsford D. L. Bottom C. A. Busack T. K. Collier J. Ferguson J. C. Garza A. M. Grover D. G. Hankin R. G. Kope P. W. Lawson A. Low R. B. MacFarlane K. Moore M. Palmer-Zwahlen F. B. Schwing J. Smith C. Tracy R. Webb B. K. Wells T. H. Williams Pre-publication report to the Pacific Fishery Management Council March 18 2009 1 Contents 1 Executive summary 4 2 Introduction 7 3 Analysis of recent broods 10 3.1 Review of the life history of SRFC. 10 3.2 Available data. 11 3.3 Conceptual approach. 11 3.4 Brood year 2004 . 15 3.4.1 Parents. 15 3.4.2 Eggs . 16 3.4.3 Fry parr and smolts. 17 3.4.4 Early ocean . 21 3.4.5 Later ocean . 30 3.4.6 Spawners . 32 3.4.7 Conclusions for the 2004 brood . 32 3.5 Brood year 2005 . 33 3.5.1 Parents . 33 3.5.2 Eggs . 33 3.5.3 Fry parr and smolts . 33 3.5.4 Early ocean . 34 3.5.5 Later ocean . 35 3.5.6 Spawners . 35 3.5.7 Conclusions for the 2005 brood . 35 3.6 Prospects for brood year 2006 . 36 3.7 Is climate change a factor . 36 3.8 Summary. 37 4 The role of anthropogenic impacts 38 4.1 Sacramento River fall Chinook. 38 4.2 Other Chinook stocks in the Central Valley . 43 5 Recommendations 47 5.1 Knowledge Gaps . 47 5.2 Improving resilience . 48 5.3 Synthesis.49 2 List of Figures 1 Sacramento River index. 8 2 Map of the Sacramento River basin and adjacent coastal ocean. . 13 3 Conceptual model of a cohort of fall-run Chinook. 14 4 Discharge in regulated reaches of the Sacramento River Feather River American River and Stanislaus River in 2004-2007. 16 5 Daily export of freshwater from the Delta and the ratio of exports to inflows. 18 6 Releases of hatchery fish. 19 7 Mean annual catch-per-unit effort of fall Chinook juveniles at Chipps Island by USFWS trawl sampling.20 8 Cumulative daily catch per unit effort of fall Chinook juveniles at Chipps Island by USFWS trawl sampling in 2005. 20 9 Relative survival