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  • Title

    Directed Outflow Project

    Lead U.S. Bureau of Reclamation [USBR]
    Description The U.S. Bureau of Reclamation (USBR) and California Department of Water Resources (DWR), along with collaborators, are continuing efforts to evaluate the hypothesized benefits of outflow and outflow alteration for Delta Smelt. The collective aim of these efforts is to better inform management actions that will bolster and stabilize the Delta Smelt population. The planned five-year Directed Outflow Project (DOP) seeks to assist in evaluating the overarching hypothesis that habitat quality and quantity is improved in the summer/fall when X2 is below 81 km and the LSZ occurs in Suisun Bay and Marsh, and this improvement in habitat conditions will translate into a greater catch density, health, and growth for Delta Smelt using this area
    Science topics Delta Smelt, Fish, Flows, Water management
    Updated November 17, 2022
  • 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 May 23, 2023
  • 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 Landscape metrics, Restoration planning, Marsh wildlife, Riparian wildlife, Terrestrial wildlife, Fish
    Updated April 29, 2022
  • Title

    Delta Landscapes Primary Production Project

    Lead San Francisco Estuary Institute [SFEI]
    Description This project compares first-order estimates of primary production among five major groups of primary producers, historically and today, to better identify the potential food production of different habitat types, and inform restoration actions that could increase food availability for wildlife.
    Science topics Primary production, Phytoplankton, Emergent macrophytes, Epiphytic algae, SAV/FAV
    Updated April 29, 2022
  • Title

    Delta Landscape Scenario Planning Tool

    Lead San Francisco Estuary Institute [SFEI]
    Description The Delta Landscapes Scenario Planning Tool is a set of resources to assist users with developing, analyzing, and evaluating different land use scenarios in the Delta. The tool is designed to inform ongoing and future restoration planning efforts by assessing how proposed projects will affect a suite of landscape metrics relating to desired ecosystem functions.
    Science topics Fish, Landscape metrics, Marsh wildlife, Restoration planning, Riparian wildlife, Sea level rise, Terrestrial wildlife
    Updated November 17, 2022
  • 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

    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 November 19, 2022
  • 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

    An Improved Genomics Tool for Characterizing Life History Diversity and Promoting Resilience in Central Valley Chinook Salmon

    Lead Michigan State University
    Description This study will improve our ability to protect the diversity of traits in Chinook salmon. The diversity of Chinook salmon migration timing is decreasing in the Central Valley. A key roadblock to protecting diversity is the current inability to rapidly and inexpensively identify large numbers of individuals from different populations during their migration to the ocean. This study addresses this information gap by leveraging pre-existing genomic data to develop a new technique that will allow scientists to identify individuals to life history type and location. For example, this study will potentially be able to identify Fall Run Chinook that are from the Sacramento versus the San Joaquin River basins. This information, in combination with data on water temperature and river flows, can determine the relationship between environmental conditions and juvenile salmon life history diversity. The information generated by this work will provide managers with the ability to accurately monitor the effect of key management actions on the different Central Valley Chinook salmon populations.
    Science topics Chinook Salmon, Estuaries, Fish, Habitat restoration, Resilience, Salmon rearing
    Updated November 29, 2022
  • Title

    Changes in Organic Carbon and Food Resources in Response to Historical Events in the Sacramento-San Joaquin Delta: A Synthesis Project

    Lead Virginia Institute of Marine Science
    Description Recent management strategies in the Delta rely on habitat restoration and water quality improvement to restore ecosystem function. However, current monitoring programs have been limited in their ability to measure ecosystem functions such as food webs. This study explores changes to the sources, quantity, and quality of organic carbon that support the Delta food web. Data from fifteen sites selected to represent the dominant sub-habitats in the Delta will identify the available food resources. The project examines how food resources are affected by wastewater treatment and habitat restoration. Information about organic carbon in the historic and current Delta will aid in establishing realistic goals and targets for ongoing and future restoration efforts in the Delta.
    Science topics None specified
    Updated April 29, 2022
  • Title

    Consequences of Phragmites invasion for community function in Suisun Marsh

    Lead University of California - Davis [UC Davis]
    Description This project aims to quantify the impacts of common reed (Phragmites) invasion on community structure and ecosystem function during early stages of tidal restoration in wetlands. The study will focus on the Tule Red Tidal Restoration site in Suisun Marsh. The research aims to produce a conceptual model that will describe habitat structure, invertebrate communities, and predator use of wetlands affected by Phragmites invasion. The conceptual model resulting from this study will guide future predictions of wetland response to invasion and to develop mitigation strategies. Data collected will also support food web models and the understanding of invasive plants as stressors, as well as foster translational science to the management community.
    Science topics Invasive / non native species
    Updated April 29, 2022
  • Title

    Risk of fish predation within and across tidal wetland complexes

    Lead University of California - Davis [UC Davis]
    Description This study focuses on understanding how restored tidal wetlands with different physical configurations function as refuge and rearing habitat for fishes, including native and imperiled species such as delta smelt and juvenile Chinook salmon. This research will assess the spatial distribution of predation risk as it varies within and across tidal wetlands. The proposed research will generate a statistical model that helps predict predation outcomes from various restored tidal wetland designs and channel configurations. This will be a powerful tool for managers to forecast how proposed habitat restoration or water management actions may impact native fish populations.
    Science topics Tidal wetlands
    Updated April 29, 2022
  • Title

    Wetland carbon sequestration and impacts of climate change

    Lead California State University [CSU]
    Description This project aims to improve understanding of atmospheric and hydrologic carbon fluxes in a restored tidal salt marsh in the South San Francisco Bay. I will use soil chambers to measure how much carbon dioxide and methane is taken in and emitted from the marsh. The project will also examine how spatial variability in marsh surface cover impact these exchanges. Shahan will use the data collected in this study to create a biogeochemical model that estimates the carbon budgets of wetlands in the Bay-Delta. A complete carbon budget will illuminate relationships between carbon fluxes and environmental variables. This information can support more informed management of wetlands, as well as allow researchers and decision makers to more effectively plan wetland restoration to be effective in managing carbon fluxes in the face of possible impacts due to climate change.
    Science topics Wetlands
    Updated April 29, 2022
  • Title

    Environmental geochemistry and tidal wetland support of pelagic food webs

    Lead University of California - Davis [UC Davis]
    Description This project aims to characterize and quantify where detrital material (decaying plant matter) originates within wetlands, the composition of that material, and how export of detrital particles occurs. This project will combine powerful characterization tools and techniques that scale from molecules to ecosystems to assess spatial and temporal trends in particle sources, species and composition. Because restoration in the Sacramento-San Joaquin Delta will fundamentally alter particle distribution and food availability for aquatic organisms, this study will inform habitat restoration efforts and the revival of native fish populations. The tools developed and adapted for this project may inform management response during extreme conditions and climate events by helping to identify areas that may act as refugia for species.
    Science topics Wetlands
    Updated April 29, 2022
  • 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

    From Microbes to Zooplankton, What Defines a Beneficial Wetland?

    Lead San Francisco State University, Estuary & Ocean Science Center
    Description Our study will characterize species diversity at multiple levels of biological organization in the water column of restoring wetlands in the upper San Francisco Estuary and Delta (SFE), from bacteria to fishes. In doing so, we will also describe the foodweb benefits being provided to larval fishes, including longfin smelt, through additional dietary DNA analysis. We will use the species diversity we find in the water column to identify a subset of biota that are indicative of the conditions present in wetlands in different stages of restoration (early, intermediate, and mature) and identify connections between those indicators to the foodweb resources being provided to higher trophic levels. We will study 3-4 wetlands in each of 3 stages: early (unvegetated), intermediate (partially vegetated and partially channelized), and mature (fully vegetated and channelized) wetlands.
    Science topics Crustaceans, Cyanobacteria, Estuaries, Fish, Food webs, Habitat, Habitat restoration, Insects, Invertebrates, Longfin Smelt, Other species, Other zooplankton, Pelagic fish, Phytoplankton, Predation, Restoration, Salinity, Saltwater / freshwater marshes, Tidal wetlands, Wetlands, Zooplankton
    Updated January 31, 2024
  • Title

    Analysis of Delta Salinity during Extended Drought – Pilot Project

    Lead California Department of Water Resource [DWR]
    Description Managing California water operations for multiple priorities under long term drought conditions is becoming an increasing challenge which is compounded by potential sea level rise. This project is a pilot exercise to demonstrate the utility of hydrodynamic and salinity transport models in to understand options for salinity management under extended drought combined with climate change and sea level rise. The project will also consider how to make model outputs available and relevant to other modeling and environmental management decision making efforts. The full range of potential sea level rise, restoration and operational actions is extensive, involving many potential combinations of individual actions. Therefore, it is difficult to fully explore potential actions with high resolution multi-dimensional models. The proposed approach is to use high resolution multi-dimensional flow and transport models to evaluate changes in transport in the Delta under sea level rise, restoration, and operational scenarios. The predicted changes to salinity for a given scenario will inform operations modeling in CALSIM through re-calibration of an ANN to approximately account for the changed salinity response of the estuary. Operations modeling incorporating the revised ANN will then estimate Delta inflows and overall water cost to meet Delta standards for the scenario. “Round-trip” modeling will be performed using the detailed Delta models to verify that the predicted hydrologic inputs allow appropriate compliance with water quality standards and will provide other metrics related to Delta transport.
    Science topics Conductivity, Drought, Landscape change, Restoration planning, Sea level rise, Water operations / exports
    Updated January 29, 2024