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Management theme
Delta As Place
Environmental Conditions
Flood Risk And Land Use Management
Governance
Habitat Management
Invasive / Non-native Species Management
Native Species Management
Water Quality
Water Supply Management
Science theme
Amphibians And Reptiles
Aquatic Vegetation
Biological Resource Use
Channelized Habitats
Climate Science
Environmental Conditions
Fish
Floodplain
Food Webs
Habitat Changes
Hydrologic Changes
Hydrology And Hydrodynamics
Invasive / Non-native Species
Invertebrates
Land Use And Human Activities
Landform And Natural Disturbance
Mammals
Nutrients, Energy And Food Web
Riparian Habitats
Sediment
Social Impacts
Social Science
Species
Terrestrial Habitats
Tidal Wetlands
Traditional Knowledge
Vulnerability Assessment
Water Quality
Weather And Climate
Type
Core Monitoring
Status And Trend Monitoring
Synthesis
Targeted Foundational Research
Targeted Immediate Research
Unsure
Delta region
Cache Slough Complex
East Delta
Entire Delta
North Delta
South Delta
Suisun Marsh
Twitchell And Sherman Complex
West Delta
Yolo Bypass
Yolo Bypass And Cache Slough Complex
Status
Awarded / Initiating
Complete
In Progress / Ongoing
Advanced
Science function
Data Application / Analytics
Data Application – Data Analysis
Data Application – Information Management
Data Application – Modeling
Data Application – Science Communication / Knowledge Synthesis
Monitoring – Effectiveness
Monitoring – Implementation
Monitoring – Status And Trends
Planning And Guidance
Research
Management actions
Agricultural Production
Carbon Markets
Climate Change Mitigation
Creation Of Favorable Habitat Conditions For Native Species
Flood Control
Ghg Emissions
Groundwater Protection & Management
Habitat Protection / Enhancement / Restoration
Improving Methods And/or Infrastructure For Science And Monitoring
Invasive Species Control And Management
Land Use Designation
Methylmercury Tmdl
Natural Environmental Flows
Pathways Of Introduction Of Invasives
Pollution Control
Population Enhancement Of Listed Species
Predation
Salinity Gate Management
Sea-level Rise Accommodation
Subsidence Reversal
Wastewater Management
Water Conveyance / Infrastructure
Water Demand
Water Operations
Water Storage
Wetland Resilience
Wetlands
Science topics
Above-highwater Refugia
Agriculture
Air Temperature
Algae
Ammonia
Amphibians And Reptiles
Aquatic Vegetation
Arsenic
Atmosphere
Backwater
Bedload
Benthic
Benthos
Bioaccumulation
Biosentinels
Birds
Bivalve
Brazilian Waterweed
Cadmium
California Tiger Salamander
Carbon
Carbon Storage
Chemistry
Chinook Salmon
Chlorophyll A / B
Climate Change
Conductivity
Constituent Of Emerging Concern Cec
Copper
Corbicula/potamocorbula
Crustaceans
Cyanobacteria
Delta Islands
Delta Smelt
Deposition
Detritus
Direction
Dissolved Oxygen
Docks And Ports
Dredging
Drought
Emergent Macrophytes
Endangered Species
Endocrine Disruptors
Energy And Mines
Environmental Drivers
Epiphytic Algae
Erosion
Estuaries
Evaporation / Evapotranspiration
Extreme Heat
Extreme Storms
Fecal Coliform / E. Coli
Fish
Fishing
Flame Retardants
Floating Aquatic Vegetation
Flood
Flows
Flushing Rates
Food Webs
Forest Harvesting
Forests
Fungicides
Giant Garter Snake
Giant Reed
Green Sturgeon
Greenhouse Gas Ghg
Groundwater
Gulls
Habitat
Habitat Restoration
Harmful Algal Blooms Hab
Herbicides
Hg And Methyl Mercury
Historical Ecology
Hunting
Hydrocarbons / Polycyclic Aromatic Hydrocarbons Pah
Insecticides
Insects
Intertidal / Transition Zones
Invasive / Non Native Species
Invertebrates
Jellyfish
Land Elevation
Landscape Change
Landscape Metrics
Lead
Levees
Light
Longfin Smelt
Main Channels
Mammals
Managed Ponds
Marsh Wildlife
Methylmercury
Microplastics
Mollusks
Mudflats
Mysis
Nitrogen
Nitrogen / Ammonia
Non-forested Vegetation
Non-resident / Overwintering Birds
Nutria
Nutrients
Open Water
Other Discharge Contaminants
Other Species
Other Zooplankton
Outflow
Pacific Flyway
Pelagic Fish
Pesticides
Ph
Phosphorous
Phragmites
Phytoplankton
Polychlorinated Biphenyl Pcb
Precipitation
Predation
Primary Production
Rail Lines
Recreation & Tourism
Remote Sensing
Residence Time
Resilience
Restoration
Restoration Planning
Riparian Wildlife
Roads And Bridges
Rodenticides
Sacramento Splittail
Salinity
Salmon Migration
Salmon Rearing
Salt Marsh Harvest Mouse
Saltwater / Freshwater Marshes
Sav/fav
Sea Level Rise
Seasonally Flooded
Sediments
Seismicity
Selenium
Shorebirds
Sloughs
Snowpack / Snow Water Equivalent Swe
Socio-economic Drivers
Soil
Solar Irradiance
Spongeplant
Stage
Steelhead Trout
Stormwater Runoff / Drainage
Striped Bass
Sturgeon
Submerged Aquatic Vegetation
Subsidence
Surface Water / Flow
Suspended Sediment
Temperature
Terrestrial Wildlife
Tidal Wetlands
Tides
Toxicity
Turbidity
Urban Development
Velocity
Vessels And Shipping Channels
Wastewater Discharge
Water
Water Conveyance / Infrastructure
Water Hyacinth
Water Intakes, Fish Screens & Passage
Water Management
Water Operations / Exports
Water Storage
Water Temperature
Water Use / Demand
Waterfowl
Waves
Wetland Mapping
Wetlands
White Sturgeon
Wildfire
Wind
Yellow Star Thistle
Zinc
Zooplankton
Science action area
1a. Establish Publicly Accessible Repositories, Interactive Platforms, And Protocols For Sharing Information, Products, And Tools Associated With Monitoring And Modeling Efforts, In Support Of Forecast And Scenario Development, Timely Decision-making, And
1b. Develop Tools To Assist Adaptive Management In The Delta
1c. Identify And Implement Large-scale Experiments That Can Address Uncertainties In The Outcomes Of Management Actions For Water Supply, Ecosystem Function, And Socioeconomic Conditions In The Delta.
2a. Evaluate And Update Monitoring Programs To Ensure Their Ability To Track And Inform The Management Of Climate Change Impacts, Emerging Stressors, And Changes In Species Distributions.
3a. Conduct Studies To Inform Restoration And Approaches To Protecting Human Communities That Are Resilient To Interannual Hydrologic Variation And Climate Change Impacts.
3b. Develop Integrated Frameworks, Data Visualization Tools, And Models Of The Delta Social-ecological System That Evaluate The Distribution Of Environmental Benefits And Burdens Of Management Actions Alongside Anticipated Climate Change Impacts.
4a. Use Multi-method Approaches (e.g., Surveys, Interviews, Oral Histories, And/or Observations) To Develop An Understanding Of How Human Communities’ Values, And Uses Of Cultural, Recreational, Agricultural, And Natural Resources Vary Across Geography, D
4b. Synthesize Existing Data And Collaboratively Develop Additional Long-term Data Collection And Monitoring Strategies To Address Knowledge Gaps On Human Communities Within The Delta And Those Reliant On The Delta, With The Goal Of Tracking And Modeling
4c. Measure And Evaluate The Effects Of Using Co-production Or Community Science Approaches (in Management And Planning Processes) On Communities' Perceptions Of Governance And On Institutional Outcomes, Such As Implementation Or Innovation.
5b. Identify Thresholds In The Survival And Health Of Managed Fish And Wildlife Species With Respect To Environmental Variables (e.g., Flow, Temperature, Dissolved Oxygen) And Location-specific Survival Probabilities To Develop Strategies That Will Suppor
6a. Evaluate How Climate Change, Sea Level Rise, And More Frequent Extremes Will Impact Habitats, Water Supply, Water Quality, Sediment Supply, Long-term Species Persistence, Primary Productivity, And Food Webs.
6e. Predict And Test How Water Allocation And Supply Decisions, And Ecological Flow Scenarios Should Change Under Projected Climate Change To Maintain Habitat Conditions, Access Of Target Species To Critical Habitat, And Interactions Among Native And Inva
N/a (project Initiated Prior To 2017)
Saa Action Area 1 (2017-2021): Invest In Assessing The Human Dimensions Of Natural Resource Management Decisions
Saa Action Area 2 (2017-2021): Capitalize On Existing Data Through Increasing Science Synthesis
Saa Action Area 3 (2017-2021): Develop Tools And Methods To Support And Evaluate Habitat Restoration
Saa Action Area 4 (2017-2021): Improve Understanding Of Interactions Between Stressors And Managed Species And Their Communities
Saa Action Area 5 (2017-2021): Modernize Monitoring, Data Management, And Modeling
Saa Need 1 (2022-2026): Improve Coordination And Integration Of Large-scale Experiments, Data Collection, And Evaluation Across Scales And Institutions
Saa Need 2 (2022-2026): Enhance Monitoring And Model Interoperability, Integration, And Forecasting.
Saa Need 3 (2022-2026): Expand Multi-benefit Approaches To Managing The Delta As A Social-ecological System
Saa Need 4 (2022-2026): Build And Integrate Knowledge On Social Processes And Human Behavior To Support Effective And Equitable Management
Saa Need 5 (2022-2026): Acquire New Knowledge And Synthesize Existing Knowledge Of Interacting Stressors To Support Species Recovery
Saa Need 6 (2022-2026): Assess And Anticipate Climate Change Impacts To Support Successful Adaptation Strategies
Unspecified
Start year
End year
Organizations and funding programs
Lead implementing organization
Audubon Canyon Ranch
CALFED Bay-Delta Program
California Department of Conservation [DOC]
California Department of Fish and Wildlife [CDFW]
California Department of Forestry and Fire Protection [CALFIRE]
California Department of Parks and Recreation [PARKS]
California Department of Pesticide Regulation [DPR]
California Department of Transportation [Caltrans]
California Department of Water Resource [DWR]
California Energy Commission [CEC]
California Rice Commission
California Sea Grant
California State Coastal Conservancy
California State University - East Bay
California State University Long Beach
California State University Maritime Academy
California State University [CSU]
California State Water Resources Control Board [SWRCB]
California Water Board - Central Valley Region
Central Valley Regional Water Quality Control Board [Central Valley RWQCB]
Coastal Conservation and Research, Inc.
Contra Costa Water District [CCWD]
Cornell University - Lab of Ornithology
Cramer Fish Sciences
Delta Regional Monitoring Program [RMP]
Delta Stewardship Council
Delta Stewardship Council - Delta Science Program
DigitalGlobe
East Bay Municipal Utilities District
European Space Agency
Goddard Space Flight Center
Hydrofocus Inc.
Land IQ
MarineTraffic
Metropolitan Water District of Southern California
Michigan State University
National Aeronautics and Space Administration [NASA]
National Agricultural Statistics Service [NASS]
National Audubon Society
National Marine Fisheries Service [NMFS]
National Oceanic and Atmospheric Administration [NOAA]
Oregon State University
Pacific Flyway Council
Pacific States Marine Fisheries Commission [PSMFC]
Pardee RAND Graduate School
Point Blue Conservation Science
Port of Stockton Board of Commissioners
Portland State University
R2 Resource Consultants Inc.
Sacramento-San Joaquin Delta Conservancy
San Diego State University
San Francisco Estuary Institute [SFEI]
San Francisco State University [SFSU]
San Francisco State University, Estuary & Ocean Science Center
San Joaquin County and Delta Water Quality Coalition [SJCDWQC]
Santa Clara University
Sierra Streams Institute
Southern California Stormwater Monitoring Coalition [SMC]
Stanford University
State Water Contractors [SWC]
Suisun Resource Conservation District
The Institute for Bird Populations
U.S. Army Corps of Engineers [USACE]
U.S. Bureau of Reclamation [USBR]
U.S. Department of Agriculture [USDA]
U.S. Department of Energy - Office of Biological and Environmental Research [DOE-BER]
U.S. Department of Transportation [DoT]
U.S. Environmental Protection Agency [USEPA]
U.S. Fish and Wildlife Service [USFWS]
U.S. Geological Survey [USGS]
UNAVCO
University of California
University of California - Berkeley [UC Berkeley]
University of California - Davis [UC Davis]
University of California - Los Angeles [UCLA]
University of California - Merced [UC Merced]
University of California - Riverside [UC Riverside]
University of California - San Diego [UCSD]
University of California - Santa Barbara [UCSB]
University of California - Santa Cruz [UCSC]
University of Maryland - Center for Environmental Science
University of Vermont, USGS Vermont Cooperative Fish and Wildlife Research Unit
University of Washington [UW]
Virginia Institute of Marine Science
Westside San Joaquin River Watershed Coalition
Woodland-Davis Clean Water Agency
Partner implementing organizations
Agricultural Coalitions: Landowners membership fees
Anchor QEA
Bachand and Associates
Bureau of Transportation Statistics [BTS]
California Cooperative Anadromous Fish and Habitat Data Program [CalFish]
California Department of Conservation [DOC]
California Department of Fish and Wildlife [CDFW]
California Department of Food and Agriculture [CDFA]
California Department of Forestry and Fire Protection [CALFIRE]
California Department of Parks and Recreation [PARKS]
California Department of Pesticide Regulation [DPR]
California Department of Public Health [CDPH]
California Department of Water Resource [DWR]
California Environmental Protection Agency [CalEPA]
California Heritage: Indigenous Research Project
California Institute of Technology Jet Propulsion Laboratory
California Institute of Technology [Caltech]
California Landscape Conservation Cooperative [CALCC]
California Natural Resources Agency [CNRA]
California Office of Environmental Health Hazard Assessment [OEHHA]
California State Board of Equalization
California State Coastal Conservancy
California State Lands Commission [CSLC]
California State University [CSU]
California State Water Resources Control Board [SWRCB]
Central Valley Flood Protection Board [CVFPB]
Central Valley Joint Venture
Central Washington University [CWU]
Chapman University
Collaborative Adaptive Management Team [CAMT]
Conservation Farms and Ranches
Cramer Fish Sciences
Delta Conservancy
Delta Stewardship Council
Delta Stewardship Council - Delta Science Program
Department of Fish and Game [DFG]
Desert Research Institute [DRI]
Ducks Unlimited
East Bay Municipal Utilities District
EcoMetric Consulting
Environmental Science Associates
Fishery Foundation of California
FloodSAFE Environmental Stewardship and Statewide Resources Office [FESSRO]
Hydrofocus Inc.
ICF International Inc.
International Institute for Applied Systems Analysis
Interstate Council on Water Policy [ICWP]
Koy'o Land Conservancy
Land IQ
Lawrence Berkeley National Laboratory [LBNL]
Lawrence Livermore National Laboratory
Maine Prairie High School
Manomet Inc.
Metropolitan Water District of Southern California
Michigan State University
Moss Landing Marine Laboratories [MLML]
National Aeronautics and Space Administration [NASA]
National Agricultural Statistics Service [NASS]
National Agriculture Imagery Program [NAIP]
National Audubon Society
National Marine Fisheries Service [NMFS]
National Oceanic and Atmospheric Administration [NOAA]
National Science Foundation [NSF]
National Wetlands Inventory - Many Supporting Organizations
NatureServe
Northwest Alliance for Computational Science and Engineering - PRISM Climate Group
Pacific Northwest National Laboratory
Pacific States Marine Fisheries Commission [PSMFC]
Point Blue Conservation Science
Purdue University
RAND Corporation
Resource Management Associates [RMA]
Restore the Delta
Rohde Environmental Consulting, LLC
SUNY College of Envir. Science & Forestry
Sacramento Regional County Sanitation District [Regional San]
Sacramento-San Joaquin Delta Conservancy
San Francisco Bay Bird Observatory
San Francisco Bay Conservation & Development Commission [BCDC]
San Francisco Estuary Institute [SFEI]
San Francisco State University [SFSU]
San Joaquin County Resource Conservation District
San Joaquin Valley Drainage Authority
Santa Clara University
Shingle Springs Band of Miwok Indians
Solano Land Trust
South Yuba River Citizens League
Southern California Coastal Water Research Project [SCCWRP]
Southern California Stormwater Monitoring Coalition [SMC]
Southwest Climate Adaptation Science Center
State Water Contractors [SWC]
Suisun Resource Conservation District
Texas A&M
The Nature Conservancy
U.S. Army Corps of Engineers [USACE]
U.S. Bureau of Indian Affairs [BIA]
U.S. Bureau of Land Management [BLM]
U.S. Bureau of Reclamation [USBR]
U.S. Census Bureau
U.S. Department of Agriculture [USDA]
U.S. Department of Defense [DoD]
U.S. Department of Energy [DOE]
U.S. Energy Information Administration [EIA]
U.S. Environmental Protection Agency [USEPA]
U.S. Fish and Wildlife Service [USFWS]
U.S. Forestry Service [USFS]
U.S. Geological Survey [USGS]
U.S. National Park Service [NPS]
University of British Columbia [UBC]
University of California - Berkeley [UC Berkeley]
University of California - Davis [UC Davis]
University of California - Irvine [UCI]
University of California - Merced [UC Merced]
University of California - San Diego [UCSD]
University of California - Santa Barbara [UCSB]
University of California - Santa Cruz [UCSC]
University of Kansas
University of South Carolina
University of Washington [UW]
Utah State University
Washington Department of Fish and Wildlife
Western Ecosystems Technology Inc.
Western States Water Council [WSWC]
Wolf Creek Community Alliance
Yuba River Management Team
Primary funding organizations
CALFED Bay-Delta Program
California Department of Fish and Wildlife [CDFW]
California Department of Water Resource [DWR]
Delta Regional Monitoring Program [RMP]
Delta Stewardship Council
Interagency Ecological Program [IEP]
State Water Contractors [SWC]
U.S. Bureau of Reclamation [USBR]
U.S. Environmental Protection Agency [USEPA]
U.S. Fish and Wildlife Service [USFWS]
U.S. Geological Survey [USGS]
Funding programs
California Department of Fish and Wildlife CDFW - Prop 1
Delta Regional Monitoring Program RMP
Delta Science Program - Delta Science Solicitations
Delta Science Program - Operation Baseline
Delta Science Program and California Sea Grant - Delta Science Fellows Program
Interagency Ecological Program IEP
Funding Sources
CalFED Bay Delta Fund CBDF
California Department of Fish and Wildlife CDFW - General Fund
California Department of Fish and Wildlife CDFW - Prop 1
Delta Stewardship Council - General Fund
Proposition 50
Proposition 84
Wetland Program Development Grant
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Records
Currently, sorted by last updated
Last updated
Title
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Title
Identification of environmental conditions driving cyanobacterial multi-species blooms and their toxicity using genome resolved metagenomics
Lead
University of California - Berkeley [UC Berkeley]
Description
In recent years the Sacramento-San Joaquin Delta has seen an increase in toxigenic cyanobacterial diversity and abundance during harmful cyanobacterial bloom events (cyanoHABs). This increased cyanobacterial diversity parallels an increase in the number of detected toxins during cyanoHABs outside of the typical microcystins that have been previously identified. Currently there are critical knowledge gaps around the full toxigenic potential of rising diversity of cyanobacterial species, and how the total microbial community of cyanoHABs interacts within itself and with external abiotic factors in ways that may promote the expansion of new and diverse cyanoHABs. The goal of this study is to use genome-resolved metagenomics to study the genetic diversity and metabolic and toxigenic potential of cyanoHABs to i) identify cyanobacterial taxa composition and their potential for toxins biosynthesis ii) characterize species succession dynamics and metabolic processes of the full microbial community during cyanobacterial bloom phases, iii) correlate environmental factors and toxin titers with biological components of diverse bloom phases to explain the development of cyanobacterial multi-species dominated bloom.
Science topics
Cyanobacteria
,
Harmful algal blooms HAB
Updated
February 27, 2025
Title
Fish out of breath: Assessing, developing, and validating physiological bioindicators of hypoxia across the Delta
Lead
University of California - San Diego [UCSD]
Description
This proposal seeks to generate two management tools to optimize ongoing conservation efforts (e.g. wetland restoration, fish supplementation) by accomplishing the following 4 objectives: Objective 1) use controlled laboratory experiments to identify temperature-dependent hypoxia tolerance data (Pcrit) for ChinookSalmon smolts and juvenile Delta Smelt. Objective 2) compile existing temperature and DO monitoring data across the SFE. Objective 3) generate metabolic indices using the newly-generated physiological data (Obj. 1) and existing environmentalinformation (Obj. 2) to examine spatial and temporal patterns in metabolic stress for each species. Objective 4) explore and develop an otolith-based bioindicator to identify past hypoxia exposure.
Science topics
Chinook Salmon
,
Delta Smelt
,
Dissolved oxygen
,
Temperature
Updated
February 28, 2025
Title
Restoring tidal marsh foodwebs: assessing restoration effects on trophic interactions and energy flows in the San Francisco Bay-Delta
Lead
University of California - Berkeley [UC Berkeley]
Description
The objective of this research on tidal marsh food webs is to examine whether and how restoration (via breaching dikes) may translate into recovery of diverse energy pathways and trophic interactions between basal resources, primary consumers, and predators. By comparing food webs at several tidal marshes, I will answer the following questions: (1) How does food web structure vary between reference and restored tidal marshes over time (seasons and years) and across a salinity gradient? (2)What mechanisms explain variation in food web structure within and between reference and restored tidal marshes–are they related to energy flows (food quantity, quality, transfer efficiency), community composition, or both? (3) What role do non-native species play in potentially shifting food web structure–e.g., changing community membership, sequestering energy from natives? This project builds on a large breadth of research that has used stable isotopes to characterize tidal marsh food webs in the Bay-Delta and other regions.
Science topics
Food webs
,
Wetlands
Updated
February 27, 2025
Title
Harmonizing pesticide risk management of the Bay Delta watershed
Lead
University of California - Santa Barbara [UCSB]
Description
Objective One: Employ high-resolution irrigation data to predict pesticide risks in the Bay Delta Watershed (BDW). This effort will enable more accurate prediction of health hazards given irrigation is a key driver of pesticide transport to surface and ground water. The effects of irrigation methods to pesticide transport vary significantly in their contribution of pesticides to runoff/leachate due to effects on pesticide build-up/wash-off and soil moisture conditions antecedent to precipitation. Objective Two: Provide harmonized species indicators of pesticide toxic burden releases for the Bay Delta which consider diverse resident taxa and human health. California benefits from a plethora of academic researchers, environmental advocacy groups, municipalities, and government groups working to protect the environment. Due to the complexities of this work, efforts often focus on a particular taxa or environmental compartment. This introduces a significant challenge in evaluating the pros and cons of any particular pesticide use. Currently, 79 of the 208 watersheds near the Delta which receive agricultural pesticide applications have increasing pesticide toxic burdens to aquatic taxa. Enabling evaluation of chemical alternatives which reduce toxic burdens across taxa is important to restoring ecosystem health. Objective Three. Quantify the variability of pesticide degradation and the significance to pesticide risk in the BDW. The degree to which pesticides remain in the soils of the BDW increases their probability for accumulation, transport, and nontarget affects. Degradation is highly variable in soils; an investigation of 10 pesticides in 8 soil types under equivalent conditions demonstrated a mean difference of 540% in the minimum and maximum rate of degradation for pesticides evaluated. Yet, researchers and regulators often only employ the median observed rate of degradation which may under predict risks to waterbodies of the BDW.
Science topics
Pesticides
Updated
February 27, 2025
Title
Examining the relationship between Longfin Smelt and flow in the San Francisco Bay Delta
Lead
University of California - Berkeley [UC Berkeley]
Description
The number of longfin smelt in the San Francisco Estuary has been in decline for the past several decades. While decreased freshwater flow reaching the estuary has been identified as a contributing factor, the relationship between flow and smelt populations has proven complex and appears to be changing over time. This study examined how water flow affects longfin smelt populations across different habitats in the San Francisco Estuary, analyzing decades of monitoring data from state and federal agencies. The research explored both where smelt live in the estuary and how their populations change over time in response to varying water flows. The findings show that more freshwater flow generally helps smelt populations, especially young fish in shallow waters. However, this beneficial effect appears to be weakening over time in some areas, particularly in open waters away from the shore. This suggests that smelt may be adapting to changing conditions by moving to different parts of the estuary. To help protect this threatened species, conservation efforts may need to focus on both restoring natural water flows and improving habitat conditions throughout the estuary.
Science topics
Fish
,
Flows
,
Longfin Smelt
,
Zooplankton
Updated
February 27, 2025
Title
Science for adaptive management of juvenile spring-run Chinook salmon in the San Joaquin River
Lead
University of California - Davis [UC Davis]
Description
Spring-run Chinook salmon rehabilitation efforts are intensifying on the San Joaquin River. Over the last three years, UC Davis has successfully tracked movement, behavior, reach-specific survival, and route selection for reintroduced juvenile spring-run Chinook salmon in this ecosystem. In 2019, information on salmon tracking was combined with state-of-art habitat (fast limnological automated measurements or “FLAMe”) and physiological (e.g. fish condition, survival and transcriptomic) approaches. Results from this work are ongoing but have yielded actionable information on key habitats and management strategies for promoting salmon life-cycles in the San Joaquin River and central Delta. Now UC Davis will further explore promising recent findings. First, the analysis of an additional year of juvenile salmon tracking will occur to glean more survival information across different water year conditions. This information would be married with expanded FLAMe surveys in space and time along with a second year of physiological assays using caged fish. UC Davis will also evaluate the ‘transport effect’ on salmon, in an attempt to explain consistently high losses of JSATS-tagged salmon through the restoration area. Numerous other synergies exist with new and ongoing telemetry work that will be benefitted by a continuation of this work. The goal is to provide actionable science, and open access data, with a high potential to facilitate adaptive management in the San Joaquin River and central Delta.
Science topics
Chinook Salmon
,
Endangered species
,
Estuaries
,
Fish
,
Habitat restoration
Updated
October 3, 2023
Title
Impacts of predation and habitat on Central Valley Chinook smolt survival
Lead
University of Vermont, USGS Vermont Cooperative Fish and Wildlife Research Unit
Description
The Sacramento River in California’s Central Valley has been highly modified over the past 150 years due to mining, urbanization, and impoundment/diversion of river flow to provide water for municipal, industrial, and agricultural needs. Land use changes combined with high levels of harvest have been accompanied by drastic declines in native salmon populations, including the once abundant Chinook salmon (Oncorhynchus tshawytscha). Further, the region has been subject to the introduction and widespread establishment of non-native fish species, some of which are predators of juvenile salmon. Of the four historic ecotypes of Chinook salmon (fall, late-fall, winter, and spring runs), winter- and spring-runs have been most impacted and are currently listed as endangered and threatened respectively under the US Endangered Species act. Past research has illustrated how smoltification of juvenile salmon and outmigration from freshwater to the ocean is a time of increased mortality, and reduced survival at this life stage can impact the number of reproducing adults returning to the system in subsequent years. While these studies have provided valuable information on how habitat and environmental conditions experienced by migrating Chinook salmon smolts can affect survival, they have primarily focused on individual ecotypes during the portion of the year where downstream migrations occur. However, variation in smolt size and migration timing among ecotypes can expose migrating fish to differing environmental conditions and levels of exposure to predation, which can present distinct risks for outmigration survival. To identify the areas and environmental conditions which have the greatest relative impact on juvenile survival for each ecotype, this project will use over ten years of data (2012-2022) from acoustically tagged smolts representing all four Chinook salmon ecotypes in the Sacramento River/Central Valley. Combining these data will increase sample size relative to previous studies, the range of environmental conditions (e.g., temperature, flow, and predator abundance) modeled, the range of fish sizes, and thus, the statistical power of our analyses. We hypothesize that each ecotype will have different factors that will be the primary drivers of mortality experienced during outmigration. To test our hypotheses, we will implement Cormack-Jolly-Seber (CJS) mark-recapture models to estimate both the probability of survival through reaches of the Sacramento River delineated by acoustic receivers, and the detection probability in each reach. Survival will be modeled as a function of individual, release group, reach-specific, and time-varying covariates. Further, to examine the relative impact of predation on smolt survival, we will include an additional covariate representing predator-prey encounter rates using the Mean Free-path Length model. Finally, model selection will be applied to a series of CJS models to assess the relative impact of each covariate on smolt survival for each of the four Chinook ecotypes.
Science topics
Chinook Salmon
,
Environmental drivers
,
Fish
,
Flows
,
Habitat
,
Predation
,
Salmon migration
,
Water temperature
Updated
February 2, 2024
Title
Monitoring Sacramento River winter-run Chinook salmon life history diversity, growth, and habitat use among varying hydroclimatic regimes
Lead
University of California - Berkeley [UC Berkeley]
Description
Sacramento River winter-run Chinook salmon have been endangered since 1994. Historically, the fish spawned during summer in cool tributaries upstream of Sacramento, but dams have limited spawning habitat to a small reach of the river. Today, survival of their offspring is heavily dependent on cool summer water releases from reservoirs, which also provide critical water supplies for irrigation, municipal, and industrial needs, as well as providing flood control and hydropower generation. During drought, this can lead to difficult management decisions. Understanding how winter run Chinook salmon respond to drought and water temperature is therefore vital to the management of this endangered population. This project tackled two outstanding questions about winter-run salmon ecology. The first was how winter-run Chinook use different rearing habitats during drought and non-drought periods, and the second was to explore which habitats provide enhanced growth during drought and non-drought periods. To answer these questions, UC Berkeley post-doc Pedro Morais used isotopic analysis of otoliths, or fish ear bones, which grow continuously throughout their lives and therefore carry a record of their environment and growth. Using otoliths, researchers can reconstruct details of fishes’ lives, including water temperature and migration patterns.
Science topics
None specified
Updated
February 1, 2024
Title
Evaluating contributions of hatchery-origin fish to conservation of endangered Sacramento River winter run Chinook salmon during a drought
Lead
University of California - Davis [UC Davis]
Description
Hatchery-reared fish have been used to supplement endangered winter-run Chinook salmon in the upper Sacramento River since 1989. Intense drought in the past five years has led fisheries managers to substantially modify their hatchery protocols, increasing the total number of fish released and using hatchery-origin adults for producing juveniles. However, the impact of these practices is not fully understood. This project evaluated multiple aspects of how hatchery–reared fish contribute to natural production of winter-run Chinook salmon in the upper Sacramento River. The researchers assessed whether hatchery-reared fish are spawning in the wild and producing natural-origin offspring using a novel panel of genetic markers developed during the study. The study also assessed if inadvertent domestication selection was occurring in the hatchery during the drought years and if more highly related hatchery broodstock pairings returned fewer offspring than less related pairs.
Science topics
Drought
Updated
February 1, 2024
Title
In search of refuge: Investigating the thermal life history of Delta Smelt through in-situ oxygen isotope ratio analysis of otoliths.
Lead
University of California - Davis [UC Davis]
Description
The inner ear bones of fish, or otoliths, grow continuously and their chemistry reflects the water conditions that a fish has experienced throughout its life. In this project, researchers used in-situ chemical analysis to determine the oxygen isotopic composition of otoliths, which can reflect the water temperature that a fish has experienced. They applied this method to archived adult Delta Smelt otoliths from multiple different water years spanning the time from before and during the recent drought. Using these data, they investigated the relationship between delta smelt abundance and environmental parameters, such as water temperature. More specifically they investigated whether delta smelt are able to find temperature refuges, even in drought years.
Science topics
Climate change
,
Delta Smelt
,
Endangered species
,
Fish
,
Temperature
Updated
February 26, 2024
Title
Revealing the invisible contributors to the diets of larval longfin smelt and striped bass in the San Francisco Estuary.
Lead
San Francisco State University [SFSU]
Description
To better understand why the longfn smelt is threatened, the project compared the diet of larval longfn smelt to a thriving fsh with overlapping natal habitat and of similar size and morphology— the Pacifc herring. Using new genetic analysis methods, the project aimed to elucidate species composition of fsh diets in greater detail than has been done before and to measure diferences in composition and frequency of prey across habitats. In particular, the project aimed to identify prey items that were not previously seen using traditional diet analysis methods and assess whether any prey are indicative of natal habitats
Science topics
Fish
,
Longfin Smelt
Updated
February 26, 2024