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  • Title

    Delta Wetland Resilience and Blue Carbon

    Lead San Francisco Estuary Institute [SFEI]
    Description This project estimatee carbon storage for the past, present and future Delta, as well as GHG fluxes and elevation change based on chosen restoration and rice farming scenarios in the future Delta using the Delta Landscape Scenario Planning Tool. The project also investigated how well the current organic matter parameterizations and inorganic sediment parameterization in the Marsh Equilibrium Model (MEM) represent Delta marsh accretion processes. Knowledge of marsh accretion and migration was used to develop a spatial conceptual model of marsh resilience in the Delta.
    Science topics Carbon, Greenhouse gas GHG, Resilience, Sea level rise, Subsidence, Wetlands
    Updated October 24, 2025
  • Title

    Delta Historical Ecology

    Lead San Francisco Estuary Institute [SFEI]
    Description The San Francisco Estuary Institute-Aquatic Science Center, in collaboration with the California Department of Fish and Game, completed a historical ecology study of the Sacramento-San Joaquin Delta. The project improves understanding of what the Delta looked like and how it functioned prior to the significant modification that has occurred over the last 160 years.
    Science topics Historical ecology, Landscape change
    Updated July 29, 2024
  • Title

    Delta Landscapes Project

    Lead San Francisco Estuary Institute [SFEI]
    Description

    The Delta Landscapes Project has developed a body of work to inform landscape-scale restoration of the Sacramento-San Joaquin Delta ecosystem. The project is built on knowledge, first published in 2012's Delta Historical Ecology Investigation, of how the Delta ecosystem functioned in the early 1800s (prior to the California Gold Rush and subsequent landscape-level changes).
    Science topics Fish, Landscape metrics, Marsh wildlife, Restoration planning, Riparian wildlife, Terrestrial wildlife
    Updated November 12, 2025
  • Title

    Hydrodynamic Influences on the Food Webs of Restoring Tidal Wetlands

    Lead California Department of Fish and Wildlife [CDFW]
    Description Funding will be use to implement targeted studies that examine the effect of hydrogeomorphology and biogeochemistry on aquatic habitat and resident fish. Increased knowledge of how physical processess drive fish and trophic interactions is imperative to the success of potential restoration projects in the region. Objectives are to evaluate and map the physical and hydrodynamic characteristics of the study sloughs;evaluate the effects of elevation and sea level rise;create a network of water quality stations to measure differences in slough functions;evaluate the influence of flow and tide on food production in sloughs and tidal wetlands;charaterize differences and evaluate how slough restoration effects food productions;evaluate fish community composition;evaluate fish response to habitat differences;evaluate fish use of wetlands as nursery habitats;develop recommendations for improving design of tidal wetland restoration projects to increase food availability for juvenile native fishes;evaluate the influence of flow and tide on trophic dynamics in sloughs and tidal wetlands;and characterize differences and evaluate how slough condition affects food production.
    Science topics None specified
    Updated April 29, 2022
  • Title

    Mechanisms underlying the flow relationship of longfin smelt: I. Movement and feeding

    Lead San Francisco State University [SFSU]
    Description The project is to apply modern analytical methods, bioacoustic detection and particle tracking models to refine understanding of the vertical and longitudinal distribution of longfin smelt (Spirinchus thaleichthys) and how they are affected by flow and food availability. Funding will be used to conduct the research to protect and maintain the estuary's threatened longfin smelt population.
    Science topics Longfin Smelt
    Updated November 17, 2022
  • Title

    The Effect of Drought on Delta Smelt Vital Rates

    Lead University of California - Davis [UC Davis]
    Description This Project is necessary to obtain a better understanding of the effects of drought and management's response to drought on the Delta Smelt in order to avoid extinction. This study will test predication from other models to evaluate the impact of drought and management measures on Delta Smelt responses in terms of growth, phenotype diversity and survival during the spring and summer, when drought impacts are greatest.
    Science topics Delta Smelt, Drought
    Updated November 18, 2022
  • Title

    The effects of early hypersaline acclimation due to climate change on the toxicity of pyrethroid, an insecticide, in salmonids.

    Lead University of California - Riverside [UC Riverside]
    Description Sea level rise and drought are expected to result in hypersaline waterways in the Delta. Endangered Chinook salmon and Steelhead trout go through smoltification to be able to live and mature in saline environments. However, with salinities and temperatures increasing in historically freshwater areas, these fish may be facing new stressors. Pesticide runoff into the Delta is common due to the urbanization and agriculture of many regions and can adversely affect fish. Additionally, previous research has shown that salinity exposure increases the toxicity of contaminants in anadromous fish, and it is had been demonstrated that bifenthrin, a common insecticide in the Bay, can have endocrine disrupting effects on juvenile salmonids. This project will examine the impacts of hypersaline conditions, various temperatures, and exposure to bifenthrin on the development and survival of juvenile Chinook salmon and Steelhead trout. Specifically, it will: Test the impacts of premature hypersaline acclimation and temperature on the survivial and smoltification process of a range of juvenile salmonids; Test the combined impacts of premature hypersaline acclimation, temperature, and bifenthrin exposure on smoltification, survival and behavior;and Predict the population level effects of drought and pesticide runoff on the health of endangered salmonids Additionally, this research will provide information to CA Department of Pesticide Regulation for potential pesticide management in the Delta, as well as to the CA Department of Fish and Wildlife for conservation practices of endangered juvenile salmonids in the Delta.
    Science topics Salinity
    Updated April 29, 2022
  • Title

    A Next-generation Model of Juvenile Salmon Migration through the Sacramento-San Joaquin Delta

    Lead University of California - Santa Cruz [UCSC]
    Description While migrating through the Delta and its tributaries, Chinook salmon and steelhead move through diverse habitats, encounter predators, interact with highly dynamic flows, and are impacted by a multitude of human-made structures. Funding for this Project will be use to develop integrated system-level models that will effectively manage salmonid populations and other key resources in the California Central Valley.
    Science topics Salmon migration
    Updated November 18, 2022
  • Title

    Quantifying Biogeochemical Processes through Transport Modeling: Pilot Application in the Cache Slough Complex

    Lead University of California - Davis [UC Davis]
    Description Funding for this project will focus on observations and hydrodynamic models of the Cache Slough Complex. To accomplish this, the project implementation will involve making extensive use of models developed in ongoing CDFW-funded projects. These projects have included the development and initial calibration of a two-dimensional hydrodynamic model of the Cache Slough Complex. The model utilizes the Deltares Flexible Mesh numerical model, an open-source hydrodynamic model applied in a growing number of studies in the Bay/Delta system. Work is continuing in that project to refine the model calibration within the Cache Slough Complex and extend the calibrated period. The model is also being applied to study how tidal forcing and channel configuration shape the hydrodynamic connections between parts of the system.
    Science topics None specified
    Updated November 18, 2022
  • Title

    Reconstructing juvenile salmon growth, condition and Delta habitat use in the 2014-15 drought and beyond

    Lead University of California - Davis [UC Davis]
    Description This study uses otolith chemistry and microstructure to monitor how salmon use the Delta as rearing habitat and a migratory corridor, and the mechanisms cuing their outmigration from natal rivers. We will quantify the extent to which Delta-rearing contributes to salmon population resilency under different conditions (including drought and flood conditions) and provide baseline data to assess population responses to future habitat restoration and changing climate. Physical tags are limited to larger fish that are more sea-ready than fry, and are thus ineffective to estimate the full rearing potential of Delta habitats, while abundance surveys provide only a snapshot of information. Otolith reconstructions allow us to estimate “who” is using the Delta (which populations and life history types), for how long, and their growth rates relative to other rearing habitats. This project will generate empirical data that will inform management actions aimed at maximizing salmon abundance, life history diversity, and resilience to future stressors.
    Science topics Drought
    Updated April 29, 2022
  • Title

    Identify environmental drivers influencing habitat attributes and effect on salmonids survival.

    Lead State Water Contractors [SWC]
    Description
    Science topics None specified
    Updated April 29, 2022
  • Title

    Juvenile salmon distribution, abundance, and growth in restored and relict Delta marsh habitats

    Lead California Department of Fish and Wildlife [CDFW]
    Description Project is to conduct a study that will to determine whether observed salmon responses match the assumptions and expectations of habitat suitability and life-cycle models currently guiding resource management and habitat restoration in the Bay-Delta, while at the same time supplying much-needed quantitative information to improve these models. The broader purpose is to improve these models to allow more objective and accurate predictions of alternative management and restoration actions intended to recover Central Valley salmon populations. The overarching goal of this project is to quantify the distribution, abundance, residence time and growth of juvenile salmon within the Bay-Delta.
    Science topics None specified
    Updated April 29, 2022
  • Title

    Problems and Promise of Restoring Tidal Marsh to Benefit Native Fishes in the North Delta during Drought and Flood

    Lead University of California - Davis [UC Davis]
    Description The Project will improve scientific understanding of the North Delta ecosystem and to improve better basis for management and creation of restoration sites, as well as management of the region to benefit native fishes. The Project will improve scientific understanding of how fish populations are influenced by the interactions between wetlands and hydrology, geomorphology, water quality and food availability. Funding will be use to conduct water quality monitoring;hydrodynamic modeling;and fish and invertebrate surveys.
    Science topics None specified
    Updated April 29, 2022
  • Title

    Application of cutting-edge tools to retrospectively evaluate habitat suitability and flow effects for Longfin Smelt

    Lead University of California - Davis [UC Davis]
    Description The Longfin Smelt (Spirinchus thaleichthys) is a native forage fish, characteristic of the natural biological community of the San Francisco Estuary (SFE). This study will examine variation and interactions among hatch dates, instantaneous and total growth rates, habitat use, and timing of transitions among habitats with different salinities, and variation among years with very different climate and freshwater outflow conditions. This information is crucial for managing freshwater flows and can be used to evaluate the effects of tidal wetland restoration in the San Francisco Estuary.
    Science topics None specified
    Updated June 24, 2025
  • Title

    Contaminant Effects on Two California Fish Species and the Food Web That Supports Them

    Lead University of California - Davis [UC Davis]
    Description Water temperatures are increasing due to global climate change, and are predicted to reach levels that exceed the thermal tolerance of sensitive Delta species such as the Delta Smelt by 2050. Little is directly known about the differences in sensitivity between Inland Silverside and Delta Smelt to such stressors, or how either species responds to multiple stressors. Funding will be use to study how these two species respond to drought-induced stressors (temperature, salinity, and reduced dilution of contaminants) which will provide key insights, given that one is near extinction and the other is thriving under drought conditions.
    Science topics None specified
    Updated November 19, 2022
  • Title

    Defining the fundamental niche of Longfin Smelt [Spirinchus thaleichthys]: Physiological mechanisms of environmental tolerance.

    Lead University of California - Davis [UC Davis]
    Description This Project will evaluate reproductive output, embryo to larval development, and growth and maturation of Longfin Smelt (Spirinchus thaleichthys). This Project is designed to comprehensively assess effects of extreme events and their interaction with contaminant effects, and aims to fill knowledge gaps relating to turbidity (e.g., stress levels associated with predation risk), age-specific fecundity, egg and early larval buoyancy, and other essential requirements for captive rearing conditions that will aid the successful culture.
    Science topics None specified
    Updated April 29, 2022
  • Title

    Impact of Climate Variability on Surface Water Quality: Cyanobacteria and Contaminants

    Lead University of California
    Description
    Science topics Harmful algal blooms HAB
    Updated April 29, 2022
  • Title

    Impact of Spatial and Temporal Dynamics of Water Flows on Migratory Behavior of Chinook Salmon Smolts in the South Delta

    Lead University of California - Davis [UC Davis]
    Description Funding for this study project will be use track the swimming movements of salmon smolts during migration using acoustic transmitters and detection arrays near the confluence of Old River and the San Joaquin River. Analyses will be carried out to determine swimming velocity relative to current velocity. Modeling will estimate fish distribution; fish transit times; entrainment of fish into channels of the south Delta; and alternative water export management scenarios that may result in reduced entrainment.
    Science topics None specified
    Updated November 19, 2022
  • Title

    Impacts of climate change on pesticide bioavailability and sublethal effects on juvenile Chinook salmon in the Delta: Potential benefits of floodplain rearing

    Lead University of California - Riverside [UC Riverside]
    Description The Project will include field studies to estimate loadings and bioavailability of pesticides, concentrations of pesticide residues in salmonid prey, and the trophic basis of juvenile Chinook salmon growth (benthic vs. pelagic food web pathways) and how each of these differ between floodplain and river channel habitats in the Delta. Data from the field studies will inform development of laboratory studies that will assess the potential effects of exposure to environmentally-relevant pesticide types and concentrations in prey on swimming performance, olfaction and neuroendocrinology of juvenile Chinook salmon. Laboratory studies will also evaluate how water temperature (including increased water temperatures predicted with climate change) influences these sub-lethal effects of pesticides on juvenile salmon.
    Science topics None specified
    Updated November 29, 2022
  • Title

    High-Frequency Monitoring of Delta Island Drainage Waters to inform carbon budgets and contaminant export

    Lead University of California - Santa Cruz [UCSC]
    Description This Proposition 1 funded study aims to use high-frequency measurements and paired grab samples to document water quality and carbon exports in relation to land use change on Delta Islands. The project involves monitoring one station on Twitchell Island and two on Staten Island.
    Science topics Landscape change
    Updated August 25, 2024
  • Title

    Ecosystem Engineering Impacts of Water Primrose in the Delta

    Lead University of California - Merced [UC Merced]
    Description

    Water primrose (Ludwigia spp.) is a highly invasive, non-native floating macrophyte in the Delta. In recent years, water primrose has extended its niche into marsh habitat, causing extensive mortality of marsh macrophytes including tules and cattails. The goal of this project is to determine whether the growth strategy of water primrose, its allelopathic properties, or factors related to plant community structure are the cause of marsh loss following water primrose invasion in the Delta. Part of this study will identify and map the marshes most vulnerable to loss and quantify the spatial trajectory of marsh loss during the past 15 years. The ultimate benefit will be an improved understanding of the water primrose invasion processes in the Delta, which can be used to prioritize herbicide treatment of this highly invasive plant in marshes most vulnerable to invasion and with the highest habitat value.

    Objectives:

    1. Determine which water primrose functional traits are the likely cause of marsh loss in the Delta.
    2. Determine the effect(s) of community structure on water primrose invasion success and occurrence of marsh loss.
    3. Quantify the amount and spatial trajectory of marsh loss due to primrose invasion from 2004 - 2019.
    4. Identify and map the marshes that are most vulnerable to loss due to water primrose invasion in the Delta.
    5. Disseminate findings to relevant state agencies and additional stakeholders to ensure habitat restoration success and sustainability, and to focus resources on controlling water primrose in marshes most vulnerable to loss and of highest habitat value.

     
    Science topics Aquatic vegetation, Emergent macrophytes, Environmental drivers, Floating aquatic vegetation, Habitat, Habitat restoration, Intertidal and transition zones, Invasive and non native species, Landscape change, Landscape metrics, Remote sensing, Residence time, Resilience, Restoration, SAV and FAV, Submerged aquatic vegetation, Tidal wetlands, Wetlands
    Updated December 11, 2025