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Digital Map from Dr. William Bowen California State University Northridge Sacramento- San Joaquin Delta San Joaquin River Sacramento River Suisun Bay San Francisco 2

Most fishes follow salinities Kimmerer 2004 Marine species 3

4 Most fish food follows salinities

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Variability of Freshwater Delta Inflow 6

X2=85 X2=74 7

(DS) All Years High FlowLow Flow Source: Kimmerer 2002MEPS Higher trophic levels show many relationships of abundance to freshwater flow 8 X2 (km)

High FlowLow Flow Lower trophic levels show few relationships of abundance to freshwater flow Source: Kimmerer 2002 MEPS X2 (km)

10 X2=74

11 X2=85

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14 Flows are important but so is geometry

Stationary Habitat ---Geometry Dynamic Habitat --- Hydrodynamics, ocean conditions, weather Environment Biological Conditions 15

Estuarine habitat conceptual model (Peterson 2003) Stationary Habitat Dynamic Habitat Production Area Tidal and River Flow Pelagic Recruitment 16

1873 Delta: Long residence time Marsh connections Two rivers connect to bay Waterways dendritic 17

Modern delta Short residence times Rip-rapped Cross Delta flows Rare San Joaquin connection to bay Waterways web-like 18

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Higher After Wet Springs After Wet Springs, Broad Fall LSZ Overlaps Suisun Region Higher After Wet Springs More Variable, Higher After Wet Springs More Variable, Maybe Lower After Wet Springs Always Low Narrow Fall LSZ In River Channels, Never Overlaps Suisun Region Always Lower Always Less Variable, Lower Less Variable, Maybe Higher Higher Many in South, Fewer in North Fewer Bathymetric Complexity Erodible Sediment Supply Contaminant Sources Entrainment Sites Lower Many More Net Total Delta Fall Outflow San Joaquin River Contribution to Fall Outflow Location and Extent of the Fall LSZ (1-6 psu) Hydrodynamic Complexity in the Fall LSZ Wind speed in the Fall LSZ Turbidity in the Fall LSZ Contaminant Concentrations in the Fall LSZ Stationary Abiotic Habitat Components Suisun RegionRiver Confluence Broad, Westward Higher Better May be Higher Distribution Growth, Survival, Fecundity Health and Condition Recruitment in the next Spring Constricted, Eastward Lower Worse Lower Dynamic Abiotic Habitat Components Variable Fall Outflow RegimeStatic Fall Outflow Regime Dynamic Biotic Habitat Components LSZ Overlaps Suisun RegionLSZ Overlaps River Confluence Higher Variable Food Availability and Quality Predator Abundance Lower Higher Delta Smelt Responses LSZ Overlaps Suisun RegionLSZ Overlaps River Confluence X2=74km X2= 85km

21 Regulatory Approaches FWS and NMFS (with DFG) Biological Opinions to protect smelt and salmon: In place and subject to 11lawsuits from waterusers Bay-Delta Conservation Plan: in development Regional Boards: New discharge permit for Sac Regional TMDLs for salt, boron and Selenium from San Joaquin

22 Regulatory Approaches 2 SWRCB Issued flows report in 2010 Developing new standards for San Joaquin flows and south delta salinity In 2012 will address Delta outflow requirements EPA ANPR in February 2011 What should be done about: Selenium Contaminants Emerging Contaminants Ammonium Wetlands Estuarine Habitat Migratory Corridors

How much water do fish need? 23

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What Changes As Flow Increases? X2 Location of Any Salinity Range LSZLSZ Salinity and X2 FLOW 25 stratification

Floodplains Proportion Diverted What Changes As Flow Increases? Delta Residence Time River Stage, Velocity River stage and velocity Floodplain inundation 26 FLOW Upstream bottom current

Nutrients Contaminants Organic matter Sediment What Changes As Flow Increases? Concentrations Loadings 27 FLOW

What Changes As Flow Increases? Adult spawners move up: Salmon Green and White Sturgeon Longfin smelt Delta smelt Splittail American shad Pacific herring Young Marine fish move up: Starry flounder White croaker Pacific halibut Young fish move down: Salmon Longfin smelt Delta smelt Splittail American shad Striped bass 28

1. Environmental flows are more than just volumes of inflows and outflows 2. Recent flow regimes both harm native species and encourage non-native species 3. Flow is a major determinant of habitat and transport 4. Recent Delta environmental flows are insufficient to support native Delta fishes for today’s habitats 5. A strong science program and a flexible management regime are essential to improving flow criteria Five Key Points 29

+ - Nutrients Organic matter Sediment Fish Floodplains Proportion Diverted What Changes As Flow Increases? X2X2 - Delta Residence Time - River Stage, Velocity + Location of Any Salinity Range - Salinity At a Point LSZLSZ 30

Delta smelt habitat abundance in relation to X2 31

Fish Production Benthic Production Zooplankton Production Microbial Production Phytoplankton Production Nutrient Input Organic Input Inputs Hydrodynamic Forcing : Freshwater inflow Oceanic variability Wind Stratification Transport/ Retention Physical Habitat Physical forcing mechanisms Material flows Direct physical influences Key feedback loop Conceptual Model: Physical effects on estuarine ecosystem 32