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  • Title

    Delta Wetland Resilience and Blue Carbon

    Lead San Francisco Estuary Institute [SFEI]
    Description This project estimates 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 investigates 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 will be 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 13, 2023
  • Title

    Monitoring and Evaluation of the North Delta Food Subsidies and Colusa Basin Drain Study

    Lead California Department of Water Resource [DWR]
    Description The North Delta Food Subsidies – Colusa Basin Drain Study monitors and evaluates the effects of the North Delta Flow Action on the Delta food web.
    Science topics Delta Smelt, Fish, Flows, Water management
    Updated November 17, 2022
  • 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

    Monitoring and Assessment of Suisun Marsh Salinity Control Gates Action

    Lead California Department of Water Resource [DWR]
    Description The Suisun Marsh Salinity Control Gates (SMSCGs) have the potential to provide an increase in low-salinity-zone habitat for endangered Delta Smelt. Operation of the SMSCGs in summer and fall to improve Delta Smelt habitat are called for in the Biological Opinion and Incidental Take permit for the Central Valley Project and State Water Project. To support the adaptive management of the action, DWR is planning to monitor the change in water quality, phytoplankton, zooplankton, fishes, and clams resulting from the action.
    Science topics Delta Smelt, Phytoplankton, Salinity
    Updated November 17, 2022
  • Title

    Suisun Marsh Salinity Control Gates Action Pilot Study

    Lead California Department of Water Resource [DWR]
    Description In summer 2018 we used a unique water control structure in the San Francisco Estuary to direct a managed flow pulse into Suisun Marsh. Field monitoring showed that turbidity and chlorophyll were at higher levels in Suisun Marsh, representing better habitat conditions, than the upstream Sacramento River region throughout the study period. Fish monitoring data suggested that small numbers of Delta Smelt colonized Suisun Marsh from the Sacramento River during the 2018 Flow Action.
    Science topics Delta Smelt, Phytoplankton, Salinity
    Updated September 28, 2023
  • Title

    Delta Aquatic Resource Inventory

    Lead Sacramento-San Joaquin Delta Conservancy
    Description The Delta Aquatic Resources Inventory of surface waters, wetlands and other aquatic resources in the Sacramento-San Joaquin Delta (Delta) will provide a standard regional approach to wetland classification and mapping to support wetland restoration planning, tracking, and reporting. It will faciliate implementation of the California Wetland and Riparian Areas Monitoring Plan (WRAMP) in the Delta.
    Science topics Wetland mapping
    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

    Landscape Visioning Pilot Application for Staten Island

    Lead San Francisco Estuary Institute [SFEI]
    Description A demonstration project to define possible future land use scenarios for Staten island (“visions”) and leverage existing tools/resources to analyze and compare these scenarios.
    Science topics Habitat restoration, Carbon storage
    Updated April 29, 2022
  • Title

    Delta Salmon Rearing Project

    Lead San Francisco Estuary Institute [SFEI]
    Description This project summarizes existing research and knowledge around suitable rearing habitat for Chinook salmon in the Sacramento-San Joaquin Delta;identifies areas of suitability for rearing salmon using a combined suitability analysis of four mapped habitat parameters;and provides recommendations for types of restoration needed to improve or restore rearing habitat, as well as to identify where in the Delta these restoration efforts could be prioritized.
    Science topics Salmon rearing, Salmon migration, Habitat restoration
    Updated April 29, 2022
  • Title

    Delta Regional Monitoring Program Mercury Monitoring

    Lead Delta Regional Monitoring Program [RMP]
    Description Monitoring of sport fish and water was conducted by the Delta Regional Monitoring Program (Delta RMP) from August 2016 to April 2017 to begin to address the highest priority information needs related to implementation of the Sacramento–San Joaquin Delta Estuary Total Maximum Daily Load (TMDL) for Methylmercury (Wood et al. 2010). Two species of sport fish, largemouth bass (Micropterus salmoides) and spotted bass (Micropterus punctulatus), were collected at six sampling locations in August and September 2016. The length-adjusted (350 mm) mean methylmercury (measured as total mercury, which is a routinely used proxy for methylmercury in predator fish) concentration in bass ranged from 0.15 mg/kg or parts per million (ppm) wet weight at Little Potato Slough to 0.61 ppm at the Sacramento River at Freeport. Water samples were collected on four occasions from August 2016 through April 2017. Concentrations of methylmercury in unfiltered water ranged from 0.021 to 0.22 ng/L or parts per trillion. Concentrations of total mercury in unfiltered water ranged from 0.91 to 13 ng/L. Over 99% of the lab results for this project met the requirements of the Delta RMP Quality Assurance Program Plan, and all data were reportable. This data report presents the methods and results for the first year of monitoring. Historic data from the same or nearby monitoring stations from 1998 to 2011 are also presented to provide context. Monitoring results for both sport fish and water were generally comparable to historic observations. For the next several years, annual monitoring of sport fish will be conducted to firmly establish baseline concentrations and interannual variation in support of monitoring of long-term trends as an essential performance measure for the TMDL. Monitoring of water will solidify the linkage analysis (the quantitative relationship between methylmercury in water and methylmercury in sport fish) in the TMDL. Water monitoring will also provide data that will be useful in verifying patterns and trends predicted by numerical models of mercury transport and cycling being developed for the Delta and Yolo Bypass by the California Department of Water Resources (DWR).
    Science topics Biosentinels, Fish, Methylmercury, Restoration, Water
    Updated November 17, 2022
  • Title

    Soil type as a driver of agricultural climate change response in the Sacramento-San Joaquin Delta

    Lead University of California - Berkeley [UC Berkeley]
    Description This research project aims to increase understanding of how iron-rich peatland soils cycle carbon, nitrogen, and phosphorus in the delta and establish how carbon and nitrogen biogeochemistry and greenhouse gas emissions vary with management practices and crop type. It also explores how a drier future climate will influence biogeochemistry and greenhouse gas emissions in iron-rich soils and how to best adapt land management practices. The goal of this research is to identify agricultural practices that can generate a portfolio of climate change adaptation and greenhouse gas mitigation strategies for delta farmers. The greenhouse gas data collected as part of this research also helped to generate increasingly accurate emission offset credits for potential wetland restoration projects in California’s Cap-and-Trade program.
    Science topics Agriculture, Carbon, Nitrogen, Phosphorous, Soil
    Updated November 17, 2022
  • Title

    Operation Baseline Project 2B: Phytoplankton, CSU Maritime Academy

    Lead California State University Maritime Academy
    Description Planned upgrades to the Sacramento Regional wastewater treatment plant (Regional San) between 2019 and 2021 will reduce total nitrogen inputs by >60% and shift the dominant form of nitrogen entering the Delta from ammonium (NH4) to nitrate (NO3). These changes will affect the Delta in ways unforeseeable with existing knowledge. The focus of this project is to quantify the links between wastewater nitrogen and phytoplankton standing stock, community composition and carbon and nitrogen production. Working in collaboration with the other two Operation Baseline projects, we will: 1. validate in situ monitoring approaches for phytoplankton standing stock and community composition (i.e. using size-fractionated chlorophyll-a and diagnostic phytopigments via HPLC) and 2. provide estimates of ambient and nitrogen-saturated phytoplankton NH4 and NO3 uptake rates as well as C uptake. Phytoplankton N and C uptake rates will be made along spatial gradients in nitrogen and water residence time (Task 1) and in three wetland habitats with varying influence from wastewater nitrogen (Task 3). Together with the other proposals, this project will provide much needed baseline characterization of nutrient processes in the Delta prior to Regional San upgrades.
    Science topics Algae, Floating aquatic vegetation, Food webs, Nitrogen / ammonia, Open water, Other discharge contaminants, Phytoplankton, Submerged aquatic vegetation, Wastewater discharge, Water operations / exports, Wetlands, Zooplankton
    Updated December 14, 2022
  • Title

    Operation Baseline Project 2C: Zooplankton, Romberg Tiburon Center, SFSU

    Lead San Francisco State University [SFSU]
    Description This project will examine responses of zooplankton (copepods) to variations in the foodweb attributable to nutrient sources. At each wetland site we will determine spatial abundance patterns and rates of reproduction, growth, and mortality. These will be integrated with information on phytoplankton and physical dynamics to determine how population dynamics responds to nutrient conditions. Stable isotopes will be used to assess nutrient source contributions to growth.
    Science topics Algae, Floating aquatic vegetation, Food webs, Nitrogen / ammonia, Open water, Other discharge contaminants, Phytoplankton, Submerged aquatic vegetation, Wastewater discharge, Water operations / exports, Wetlands, Zooplankton
    Updated December 14, 2022
  • Title

    Habitat, hatcheries, and nonnative predators interact to affect juvenile salmon behavior and survival

    Lead University of California - Santa Cruz [UCSC]
    Description Chinook salmon are an iconic part of California’s environment and heritage, and important both economically and culturally. In the Sacramento River, the winter-run Chinook population is endangered, and there is strong interest in restoring these populations. To do so, resource managers need to better understand the pressures on wild populations. Predation by nonnative predators affects survival of young salmon but may also affect the behavior of salmon. Changes to salmon behavior also have costs but are not currently considered in management. Managers need information on how predators affect juvenile salmon behavior, how they might vary under different conditions, and how they scale up to affect populations.
    Science topics Chinook Salmon, Fishing
    Updated November 17, 2022
  • Title

    Investigation of the resilience of the salt marsh harvest mouse and best management practices in response to climate change

    Lead University of California - Davis [UC Davis]
    Description This study aimed to investigate the response of the salt marsh harvest mouse to several threats of climate change, including extreme annual climate cycles and sea level rise. The study was based on ongoing population surveys in the Suisun Marsh, and a study of upland/elevated refuge throughout the species’ range, over the two-year study. It also involved the piloting of advance remote detection technology (camera traps, audio detectors, and digital mouse traps) and effective, affordable high tide refuge (islands and trellises). Finally, ongoing trapping efforts at established survey sites is providing data for ongoing analysis on the effects of weather patterns and space needs of populations.
    Science topics Climate change, Salt marsh harvest mouse, Saltwater / freshwater marshes
    Updated November 17, 2022
  • Title

    Effects of copper exposure on the olfactory response of Delta smelt [Hypomesus transpacificus]: Investigating linkages between morphological and behavioral anti-predator response

    Lead University of California - Davis [UC Davis]
    Description This study aimed to address the question of how water-borne copper can affect the ability of delta smelt to detect predator related odorants and conduct essential behaviors. To do this, the project included a thorough morphological and cytological study of the delta smelt olfactory organ, which had previously not been well-studied. The researchers also characterized the olfactory mediated antipredatory response to alarm cues and assessed the effects of copper exposure on the anti-predator behavior and morphology of the olfactory rosette of delta smelt.
    Science topics Copper, Delta Smelt, Toxicity
    Updated November 17, 2022
  • Title

    Effect of temperature and salinity on physiological performance and growth of longfin smelt: Developing a captive culture for a threatened species in the Sacramento- San Joaquin Delta

    Lead University of California - Berkeley [UC Berkeley]
    Description This research project aimed to improve understanding of the physiological requirements for survival and reproduction across the entire life history of longfin smelt (from egg to larvae to juvenile to reproducing adult). The overall goals of this project were to assist in developing a captive longfin smelt culture and assess longfin smelt responses to multiple stressors across all life stages, which has been difficult because of extremely low (<10%) larval survival of these fish.
    Science topics Delta Smelt, Longfin Smelt, Salinity, Temperature
    Updated November 17, 2022
  • Title

    Yolo Bypass Salmonid Habitat Restoration and Fish Passage

    Lead California Department of Water Resource [DWR]
    Description The Yolo Bypass Salmonid Habitat Restoration Project works to reconnect the floodplain for fish during the winter season and improve connectivity within the bypass and to the Sacramento River. The project provides seasonal inundation that mimics the natural process of the Yolo Bypass floodplain and improves connectivity within the bypass and to the Sacramento River.
    Science topics Chinook Salmon, Endangered species
    Updated April 29, 2022
  • Title

    Yolo Bypass Salmonid Habitat Restoration and Fish Passage: Scenario Analysis of Fremont Weir Notch – Integration of Engineering Designs, Telemetry, and Flow Fields

    Lead U.S. Army Corps of Engineers [USACE]
    Description This study analyzes 12 notch scenarios in the Fremont Weir in terms of entrainment of juvenile salmon. The goal is to quantify the relative entrainment rates (between 0 and 1) across the suite of scenarios and to identify possible strategies for enhancing entrainment outcomes. This study does not predict future entrainment as models generally do not predict future outcomes so much as highlight trends
    Science topics Chinook Salmon, Endangered species, Water conveyance / infrastructure
    Updated April 29, 2022
  • Title

    Reevaluating ecosystem functioning and carbon storage potential of a coastal wetland through integration of lateral and vertical carbon flux estimates

    Lead University of Washington [UW]
    Description This study aims to produce an integrated, net ecosystem carbon budget for Suisun Marsh, a representative ecosystem in the delta. This project combines diverse measurements on land and in the adjacent marine environment to produce the first directly measured, complete carbon budget for a coastal wetland habitat. This work has generated a more complete picture of the potential of wetland preservation for greenhouse gas reduction, as well as the processes that shape wetland accretion and resilience to sea-level rise. The project will provide vital information for understanding the ecosystem services, food webs, and carbon storage potential of the region’s wetlands, as well as provide new methodology that could be used by researchers around the world.
    Science topics Atmosphere, Carbon, Carbon storage, Evaporation / evapotranspiration, Non-forested vegetation, Sea level rise, Sediments, Surface water / flow, Wetlands
    Updated November 17, 2022
  • Title

    Do light, nutrient, and salinity interactions drive the “bad Suisun” phenomenon? A physiological assessment of biological hotspots in the San Francisco Bay-Delta

    Lead University of California - Santa Cruz [UCSC]
    Description This project assessed the physiological basis for reduced phytoplankton growth in Suisun Bay, prior to the major upgrade at the Sacramento Regional Wastewater Treatment Plant (SRWTP), which is responsible for 90% of the nitrogen released into the bay. The work involved analyzing almost three decades of historical eld data from the bay-delta and using it to build a model to evaluate environmental drivers of phytoplankton biomass. Discoveries from the eld data were then tested through laboratory culturing experiments. By illuminating the interacting e ects of bottom- up drivers (light, nutrients, salinity) on phytoplankton, this research helps provide a fundamental understanding of this complex ecosystem.
    Science topics Ammonia, Flushing rates, Light, Open water, Pelagic fish, Phytoplankton, Salinity, Wastewater discharge, Water temperature
    Updated November 17, 2022
  • Title

    Simulating methylmercury production and transport at the sediment-water interface to improve the water quality in the Delta

    Lead University of California - Merced [UC Merced]
    Description The aim of this project was to improve basic knowledge of mercury cycling and aid management of net methylmercury production in the delta by developing a kinetic-thermodynamic reaction model that describes and quantifies mercury cycling in delta sediments. The model was used to assess uncertainties and estimate methylation and demethylation rates — the processes by which methylmercury is produced and breaks down. In addition, the project examined coupling of mercury cycling with cycling of iron, sulfur, and manganese.
    Science topics Bioaccumulation, Chemistry, Hg and methyl mercury
    Updated November 17, 2022
  • Title

    Defining habitat quality for young-of-year longfin smelt: Historical otolith-based reconstructions of growth and salinity history in relation to geography, climate, and outflow

    Lead University of California - Davis [UC Davis]
    Description This project aimed to use experiments to develop new otolith-based tools for longfin smelt and to then apply them to an extensive collection of archived wild Longfin Smelt specimens, to build a better understanding of longfin smelt life history, habitat use, and the interactions between stressors and abundance. In addition, the project aims to improve the understanding of how longfin smelt populations are affected by freshwater outflow. The project also aims to provide tools to support and evaluate habitat restoration, and facilitate development of a plan to recover this threatened species.
    Science topics Longfin Smelt, Outflow, Salinity
    Updated November 17, 2022
  • Title

    Operation Baseline Project 1: Conceptual Framework

    Lead Delta Stewardship Council
    Description A multidisciplinary team will develop a thorough conceptual model that will describe current conditions and consider changes from the WWTP upgrade. The model will be used to identify the highest priority science questions and investigations to pursue before, during, and after the plant upgrade.
    Science topics Algae, Floating aquatic vegetation, Food webs, Nitrogen / ammonia, Open water, Other discharge contaminants, Phytoplankton, Submerged aquatic vegetation, Wastewater discharge, Water operations / exports, Wetlands, Zooplankton
    Updated December 14, 2022
  • Title

    Operation Baseline Project 2A1: USGS Pilot Studies

    Lead U.S. Geological Survey [USGS]
    Description Two pilot studies were funded to establish a baseline in open water and shallow wetland habitats prior to the WWTP upgrade. Study 1: Nutrient concentrations, transformation rates, and links to the foodweb. Study 2: Method to improve monitoring using fixed stations coupled with high-speed boat measurements
    Science topics Algae, Floating aquatic vegetation, Food webs, Nitrogen / ammonia, Open water, Other discharge contaminants, Phytoplankton, Submerged aquatic vegetation, Wastewater discharge, Water operations / exports, Wetlands, Zooplankton
    Updated December 14, 2022
  • Title

    Operation Baseline Project 2A2: USGS Pilot Studies - Isotopes

    Lead U.S. Geological Survey [USGS]
    Description Evaluate the usefulness of stable isotopes to trace nutrients form effluent water
    Science topics Algae, Floating aquatic vegetation, Food webs, Nitrogen / ammonia, Open water, Other discharge contaminants, Phytoplankton, Submerged aquatic vegetation, Wastewater discharge, Water operations / exports, Wetlands, Zooplankton
    Updated December 14, 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

    Investigating the Factors that Affect Distribution, Abundance, and Recruitment of Age-0 Longfin Smelt in the upper San Francisco Estuary

    Lead Metropolitan Water District of Southern California
    Description
    Science topics Longfin Smelt
    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 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

    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

    Identifying the Causes of Feminization of Chinook Salmon in the Sacramento and San Joaquin River System

    Lead University of California - Berkeley [UC Berkeley]
    Description Purpose was to assess the potential importance of endocrine-disrupting chemical contaminants to salmon and other resident speices of waters that are discharged into the San Francisco-San Joaquin Delta.
    Science topics Chinook Salmon
    Updated April 29, 2022
  • Title

    How Abiotic Processes, Biotic Processes, and Their Interactions Sustain Habiata Charactersitics and Functions in River Channels and Their Floodplains: An Investigation of How a Reach of the Merced River Responds to Restoration

    Lead University of California - Santa Barbara [UCSB]
    Description The purpose of this project is to determine how river restoration affects the abundance and distribution of salmonid and non-salmonid fishes at critical life stages. The proposal involves field survey of hydraulics, sedimentation processes, channel changes, habitat conditions, invertebrate and fish communities and their interactions.
    Science topics None specified
    Updated April 29, 2022
  • Title

    Review of Four Juvenile Salmon Coded Wire Tag Experiements Conducted in the Delta

    Lead U.S. Fish and Wildlife Service [USFWS]
    Description The US Fish and Wildlife Service, Stockton Fish and Wildlife Office, has since the mid-1980s conducted several multi-year release-recovery experiments with coded-wire-tagged juvenile Chinook salmon. The objectives of the studies were (1) to estimate survival through the lower portions of the Sacramento and San Joaquin river systems, the California Delta, and (2) to quantify the factors affecting survival. Four of these studies, listed more or less by their historical start dates, are the Delta Cross Channel, Interior, Delta Action 8, and VAMP experiments.
    Science topics Chinook Salmon
    Updated April 29, 2022
  • Title

    Predicting the Effects of Invasive Hydrozoa [Jellyfish] on Pelagic Organisms Under Changing Salinity and Temperature Regimes

    Lead University of California - Davis [UC Davis]
    Description The purpose of this project seeks to investigate the potential effects of jellyfish, a devising invader of some ecosystems, on the SFE ecosystem, to determine the key factors allowing successful establishment and spread of these species, and to predict future effects and spread of the invasions.
    Science topics Water temperature, Salinity, Pelagic fish, Jellyfish
    Updated April 29, 2022
  • Title

    Climate change impacts to San Francisco Bay-Delta wetlands: Links to pelagic food webs and predictive responses based on landscape modeling

    Lead San Francisco State University [SFSU]
    Description The purpose of this project is to 1) evaluate the potential impacts of climate change on SF Bay-Delta tidal wetlands, 2) improve our understanding of the linkage between these wetlands and the pelagic food web, especially fish populations, and 3) use this information to make predictions about potential effects of climate change on Bay-Delta fish populations.
    Science topics Pelagic fish, Wetlands
    Updated April 29, 2022
  • Title

    Quantitative Indicators and Life History Implications of Environmental Stress on Sturgeon

    Lead University of California - Davis [UC Davis]
    Description The purpose of this project is to analyze the effects of the pollutants on the overall fitness of different life stages of the green and white sturgeon. This research will significantly enhance our understanding of stressors on sturgeon and allow further development of life history models.
    Science topics Water temperature, Salinity, Pelagic fish, Methylmercury, Sturgeon
    Updated April 29, 2022
  • Title

    Comparison of Nutrient Sources and Phytoplankton Growth and Species Composition in Two Rivers: Their Roles in Determining Productivity and Food Web Conditions in Suisun Bay and the Delta

    Lead San Francisco State University [SFSU]
    Description
    Science topics Phytoplankton, Pelagic fish, Nitrogen / ammonia
    Updated April 29, 2022
  • Title

    The Transport and Dispersion of Rafting Vegetation in the Sacramento-San Joaquin Delta

    Lead University of California - Berkeley [UC Berkeley]
    Description The research we are proposing here is focused on developing a thorough, mechanistic understanding of how rafting vegetation, such as hyacinths or egeria, is transported in the Sacramento-San Joaquin Delta. Our approach is to examine in detail the forces that act on rafts of vegetation, and the resulting raft accelerations, to establish a predictive model of raft pathlines. Our model development will be built around a series of field experiments that include measurements of raft movement using GPS-logging drifters integrated into rafts, tidal and wind-forcing using a boat mounted current profiler and an anemometer, and direct estimation of the water-induced shear stress using a point velocity meter incorporated into the actual rafts. These field observations will be used to critically evaluate a numerical model of both channel (tidal) flows and resulting raft movement. Our initial development will include a highly-resolved channel flow model, which will explicitly capture more lateral variability, including low velocity side “pockets”, than is typically resolved with Delta scale hydrodynamic models. Initially, this will allow us to carefully evaluate the quality of our raft tracking calculations. Once the approach is established to be accurate, however, these high-resolution flows will be used to numerically calculate the effective advection and dispersion of rafts in the Delta channel under consideration. This analysis will be focused on parameterizing the effects on raft transport of structures and processes that are unresolved in typical Delta hydrodynamics models. An example of a process that is likely to be important to parameterize is the trapping and retention of rafts along the perimeter of channels due to off-axis wind forcing, and the resulting along-channel dispersion of rafts. In order to examine the effective advection and dispersion of rafts in Delta channels, we propose to pursue this combination of field and numerical studies of raft transport in locations of increasing complexity: first in idealized, straight channels, then in a natural, sinuous channel and a channel junction, and finally throughout the entire Delta. Our research is strongly motivated by the desire to provide a predictive model of dispersion in the Delta for floating objects that respond to both wind and tidal forcing. Immediate applications involve the movement of hyacinth rafts and egeria to evaluate potential management strategies. Important future applications are likely to include consideration of other biological invasions, due to the potential for rafts to provide a transport pathway, and analysis of the movement of accidental or intentional releases of floating material in the Delta.
    Science topics None specified
    Updated November 29, 2022
  • Title

    The Consequences of Operational Decisions on Water Quality: Reconciling Delta Smelt, Salmon, and Human Needs

    Lead Contra Costa Water District [CCWD]
    Description The purpose of this project is to assess the consequences of actions taken to protect threatened or endangered Chinook salmon species relative to other upstream and in-Delta water management actions that have changed seasonal salinity in the Delta, thus reducing the ability of delta smelt to survive as a species;and, to investigate with modeling scenarios the potential to ameliorate this trade-off with specific operational actions.
    Science topics Delta Smelt, Chinook Salmon
    Updated April 29, 2022
  • Title

    A Calibration-Free Approach to Modeling Delta Flows and Transport

    Lead University of California - Berkeley [UC Berkeley]
    Description The purpose of this project is to develop and evaluate an integrated system for the prediction of Delta flows and transport in real-time that doesn't rely upon historical data sets for calibration and validation. The system consists of observational and computational components, along with real-time communication and coordination.
    Science topics None specified
    Updated April 29, 2022
  • Title

    Pilot Mark-Recapture Study to Estimate Delta Smelt Pre-Screen Loss and Salvage Efficiency

    Lead U.S. Fish and Wildlife Service [USFWS]
    Description The purpose of this project is to perform a study to determine whether it is feasible to quantify entrainment losses of juvenile and adult delta smelt due to water exports. This information is critical to better understanding the movement of Delta smelt in the system.
    Science topics Delta Smelt
    Updated April 29, 2022
  • Title

    Are Apparent Sex Reversed Chinook Salmon a Symptom of Genotoxicity?

    Lead University of California - Davis [UC Davis]
    Description Goal was to test the relative importance of chemical stressors on population viability and genetic diversity for fall-run Chinook salmon (in association with environmental contaminant exposure in the Central Valley delta).
    Science topics Chinook Salmon
    Updated April 29, 2022
  • Title

    Using Flowcam Technology to Measure High Frequency Spatial and Temporal Variation in Phytoplankton and Zooplankton Species Composition and Develop State-of-the-Art Plankton Monitoring

    Lead California Department of Water Resource [DWR]
    Description The purpose of this project is to use the new imaging-in-flow instrument FlowCAM to rapidly and automatically identify, enumerate and estimate biomass for in situ and laboratory phytoplankton and zooplankton species composition samples in the SF Estuary.
    Science topics Phytoplankton, Zooplankton
    Updated April 29, 2022
  • Title

    A Non-Point Source of Contaminants to the Estuarine Food Web: Mobilized Particles from the Intertidal Zone

    Lead California State University [CSU]
    Description The purpose of this research project is to quantify the process of contaminant concentration and resuspension of shallow and intertidal cohesive sediments at sites along the salinity gradient from Prospect Island to San Pablo Bay. This research is important because it helps to understand the pathways by which contaminants are assimilated, which is essential to appropriately manage habitat areas.
    Science topics None specified
    Updated April 29, 2022
  • Title

    Estimating Juvenile Chinook Salmon Spring and Winter Run bundance at Chipps Island

    Lead U.S. Fish and Wildlife Service [USFWS]
    Description The purpose of this project will develop and implement a DNA sampling protocol for juvenile Chinook salmon captured at Chipps Island.
    Science topics Chinook Salmon
    Updated April 29, 2022
  • Title

    Analysis of Archived Samples to Assess Patterns of Historic Invasive Bivalve Biomass

    Lead California Department of Water Resource [DWR]
    Description The purpose of this project is to provide information regarding the effect of bivalves in restored habitat by assessing patterns of invasive bivalve biomass. This research is important because these bivalves are invasive and dominant in the upper SF Bay-Delta system, which are considered to be a major sink of primary productivity in the system.
    Science topics Bivalve
    Updated April 29, 2022
  • Title

    A Statistical Model of Central Valley Chinook Incorporating Uncertainty

    Lead R2 Resource Consultants Inc.
    Description The purpose of this project is to develop a statistical modeling approach to the two Central Valley Chinook Salmon species that incorporates mortality in all phases of salmon life history, and includes the effects of uncertainty in assessing population status, guiding future research, and making management decisions.
    Science topics Chinook Salmon
    Updated April 29, 2022
  • Title

    Quantifying Factors Affecting Migration Routing and Survival of Juvenile Late-Fall Chinook Salmon in the Sacramento-San Joaquin River Delta

    Lead U.S. Geological Survey [USGS]
    Description Juvenile Chinook salmon emigrating from natal tributaries of the Sacramento River must negotiate the Sacramento-San Joaquin River Delta where they disperse among the Delta's complex channel network. Natural processes and water management actions affect the fraction of the population using different migration routes through the Delta and survival within those routes, but quantifying these relationships has proven difficult. Since 2006, acoustic telemetry techniques have been used to quantify both movement among migration routes and survival within routes, providing the first insights into how route-specific survival contributes to population-level survival in the Delta. In this project, we propose to use existing acoustic telemetry data from multiple sources to 1) Quantify factors affecting migration routing of juvenile salmon emigrating from the Sacramento River, 2) Quantify factors affecting survival of juvenile salmon within specific migration routes, and 3) Simulate population-level survival through the Delta under a limited number of historical and operational scenarios. Collating telemetry data from multiple sources over numerous years offers a unique opportunity to identify important relationships that might otherwise be difficult to detect for any particular study in a given year. Quantifying such relationships is critical to informing resource management that seeks to balance use of water resources with recovery of endangered salmon populations.
    Science topics Chinook Salmon
    Updated April 29, 2022
  • Title

    Impact of Urbanization on Chinook Salmon, Steelhead Trout, and Their Prey: a Case Study of the American River

    Lead University of California - Berkeley [UC Berkeley]
    Description The American River provides spawning/rearing habitat for Chinook salmon and steelhead, yet passes through 30 miles of dense urban development. Urban runoff contains pyrethroid insecticides that cause the river to become toxic to standard testing species with every storm event. This study will go beyond observed toxicity, and address toxicity to chironomids, caddisflies, and mayflies, key diet components of juvenile fish in the river. A bioenergetic model will be used to evaluate effects of food web changes on young salmonids. Our key approach is the use of river-side systems with flowing river water that allow us to replicate realistic pesticide exposures, while controlling other variables. We will determine sensitivity to pyrethroids and fipronil of salmonid prey taxa, and expose them, as well as standard testing species, in the flow-through systems through six storm events. We will maintain experimental streams containing riverine benthic invertebrate communities, and measure response to the pyrethroid pulses. To supplement analyses of the indirect, food web-mediated effects, we will measure endocrine effects through vitellogenin induction in salmon and steelhead. Finally, one treatment includes river water from which organic contaminants have been removed by activated charcoal, to help establish cause of toxicity. The goal is to determine if known toxicity in the American River is a threat to benthic invertebrates and, through the food web, to salmon and steelhead.
    Science topics Chinook Salmon, Steelhead Trout, Above-highwater refugia, Other discharge contaminants, Food webs
    Updated April 29, 2022
  • Title

    Habitat Values of Native SAV [Submerged Aquatic Vegetation] in the Low Salinity Zone of San Francisco Estuary

    Lead San Francisco State University [SFSU]
    Description We will investigate the importance of native submerged aquatic vegetation (SAV) in providing food web support for native fish species in the low salinity zone of the San Francisco Bay-Delta. These SAV beds, composed primarily of Stuckenia pectinata (sago pondweed), are an extensive feature along many of the islands in Suisun Bay and the west Delta, yet almost nothing is known of their seasonal or interannual patterns, their invertebrate communities, or how their physical structure or food resources influence use by native fishes. We hypothesize that the position of these beds in the shallow subtidal zone along the islands increases habitat options adjacent to wetlands and channels for numerous fish species, including species of concern such as delta smelt and chinook salmon. The objectives of this project are to: 1) characterize patterns in habitat structure, community composition, and productivity of SAV beds in four locations in Suisun Bay and the western Delta over a three year period (with comparisons to non-native Egeria densa beds), 2) document the epifaunal invertebrate community composition and abundance in the Stuckenia beds, 3) assess fish use of these beds through seining and acoustic monitoring of hatchery-tagged fish, 4) utilize stable isotope analyses to evaluate food web relationships within and among the beds, and 5) begin preliminary evaluation of the potential to restore native SAV to subsided lands in this region.
    Science topics Chinook Salmon, Green sturgeon, White Sturgeon, Sacramento Splittail, Delta Smelt, Steelhead Trout
    Updated April 29, 2022
  • Title

    Physiological Mechanisms of Environmental tolerance in Delta Smelt [Hypomesus transpacificus]: From Molecules to Adverse Outcomes

    Lead University of California - Davis [UC Davis]
    Description The proposed project directly addresses priority research detailed by the Delta Science Program to protect native fishes that depend on the Bay-Delta system focusing on adaptations to local habitats and physiological tolerances to key environmental stressors;in delta smelt (Hypomesus transpacificus). Temperature and salinity changes associated with anthropogenic climate change are likely to further exacerbate delta smelt population declines. We hypothesize that delta smelt tolerance to forecasted temperature rises and salinity intrusions into the Bay-Delta system can be assessed at a mechanistic level, and that acclimation thresholds can be established by means of genomic responses. This proposal builds upon successful development of a cDNA microarray for delta smelt containing approximately 2000 individual gene fragments, and the subsequent application of biomarkers for assessing the effects of chemical stressors on larval development with links to swimming behavior. We propose to develop a Next Generation oligonucleotide microarray in delta smelt, with ca. 15K genes, in order to assess mechanistic tolerance to changes in gemperature and salinity. Genomic studies will be conducted integrating effects on energetic activity and swimming performance studies, in an interdisciplinary approach that will permit the establishment of links between tolerance mechanisms and adverse outcomes.
    Science topics Delta Smelt, Water temperature, Salinity, Turbidity
    Updated April 29, 2022
  • Title

    Nutritional Quality of Zooplankton as Prey for Fish in the Sacramento-San Joaquin Dalta

    Lead University of California - Davis [UC Davis]
    Description Primary consumers (zooplankton) are a critical trophic link for energy transfer to upper trophic levels and a key food source for threatened and endangered fish species in the Delta. The zooplankton community was shaped by large spatial and temporal changes in both abundances and species composition that affected quantity of zooplankton carbon. It is also expected that taxonomic shifts affected quality of zooplankton carbon for fish due to altering biomass transfer at the base of the food web that can profoundly influence nutritional quality and population dynamics at higher trophic levels. Yet the biochemical composition of plankton remains largely unstudied in this system despite the fact that the importance of zooplankton nutritional quality for fish is one potential major component for the long-term decline and more recent collapse of pelagic fish species. The proposed research aims to measure essential nutritional status (stoichiometry, fatty acids, sterols) for zooplankton taxa and will calculate food-quality indices for fish. On the basis of nutritional plankton and biomass values, spatial patterns as well as long-term and recent changes in plankton quality associated with compositional shifts will be estimated. We propose that through integrating plankton food-quality into the management and restoration plan for the Delta, the dynamics of the ecosystem can be viewed from a new perspective that has key implications for understanding the decline in pelagic organisms.
    Science topics Zooplankton
    Updated April 29, 2022
  • Title

    Foodweb Support for the Threatened Delta Smelt and Other Estuarine Fishes in Suisun Bay and the Western Sacramento-San Joaquin Delta

    Lead San Francisco State University [SFSU]
    Description The purpose of the project is to increase understanding of the foodweb supporting delta smelt and other estuarine species. This research is important because: 1) it could lead to increased foodweb support for the threatened delta smelt and 2) identify potential mechanisms underlying relationships of abundance or survival of some fish to freshwater flow.
    Science topics Delta Smelt
    Updated April 29, 2022
  • Title

    An Open-Source, Three-Dimensional Unstructured-Grid Model of the Sacramento/San Joaquin Delta: Model Construction and Application to Delta Hydrodynamics and Temperature Variability

    Lead Stanford University
    Description Motivated by the need to predict transport in the Delta, this project will apply the open-source, unstructured-grid computer model, SUNTANS (Stanford Unstructured Nonhydrostatic Terrain following Adaptive Navier Stokes simulator) to the Sacramento/San Joaquin Delta. SUNTANS solves the governing equations of fluid flow on a grid that permits fine detail in areas of particular interest in the Delta, while allowing us to include the entirety of the Bay/Delta system so as to properly model oceanic and estuarine influences on the Delta We have two aims:(1) to carry out the model development needed to apply SUNTANS to the Delta;(2) to apply the model to look at aspects of the physical variability of the Delta that are critical to ecosystem function and to understanding how physical processes in the Delta affect ecosystem function, most notably entrainment of fish and other organisms by the export facilities. In particular, we propose to look at flow behavior at channel junctions, a key aspect of Delta hydrodynamics that influences dispersion in the Delta and thus the transport of biota, nutrients and contaminants. We also will examine the dynamics of spatial and temperature variability in the Delta in response to tides, atmospheric forcing, river flows, and diversions, variability that must be properly calculated to forecast how climate change and altered project operations may affect key species like Delta Smelt. We will carry out new fieldwork to support our modeling.
    Science topics Water temperature
    Updated April 29, 2022
  • Title

    Integrating Ecosystems, Flood Control, Agriculture, and Water Supply Benefits: An Application to the Yolo Bypass

    Lead University of California - Davis [UC Davis]
    Description The Yolo Bypass presents an opportunity to develop mechanisms governing the management of flows across floodplains that balance ecosystem services with economic and recreational functions, and to study the untapped potential of such floodplains to play a role in conjunctive surface and groundwater management. Analysis to the necessary high degree of spatial resolution for such management decisions is generally lacking for the Yolo Bypass. This proposal seeks funding for an interdisciplinary study to better understand the economic, hydrologic, and ecological functioning of land and water across the bypass, and to develop tools that use this knowledge in identifying promising strategies for the timing and configuration of spring inundation. Agronomic, economic, and hydraulic models will be used with formal interviews to study the relationship between flooding and six Yolo Bypass functions: (1) Agricultural Economics, (2) Waterfowl management, (3) Native Fish habitat, (4) Flood Control, (5) Groundwater storage, and (6) Recreation. Data from these first efforts will be incorporated into an optimization model that identifies promising inundation alternatives for ecosystem services which minimize costs to landowners and waterfowl managers, and maximize potential conjunctive use benefits. This synthesis answers the Delta Science Program's request for coupled hydrologic and ecosystem models, and for water and ecosystem management decision support system development.
    Science topics None specified
    Updated April 29, 2022
  • Title

    CASCaDE II: Computational Asessments of Scenarios of Change for the Delta Ecosystem

    Lead U.S. Geological Survey [USGS]
    Description This proposal builds upon an existing model-based effort to develop a holistic view of the Bay-Delta-River-Watershed system. CASCaDE I developed a set of linked models to assess Delta ecosystem response to climate change. In CASCaDE II, we propose to refine and extend those modeling capabilities to assess Delta ecosystem response to changes in climate and physical configuration. With a new state-of-the-art hydrodynamic and sediment model at its core, CASCaDE II will link models of climate, hydrology, hydrodynamics, sediment, geomorphology, phytoplankton, bivalves, contaminants, marsh accretion, and fish. Our goals are to apply these linked models to 1) better understand Delta ecosystem function, 2) assess possible futures of the Delta under scenarios of climate and structural change, and 3) provide science-based information to support the DSC in its co-equal goals of water supply and ecosystem protection. The tools developed will provide an objective basis for anticipating and diagnosing Delta ecosystem responses to planned and unplanned changes. Experiments using the linked models are designed to address questions such as: How will climate change, together with new conveyance structures or increased flooded island habitat, alter water flow and drinking water quality? With projected changes in residence time, turbidity, temperature, and salinity, how will primary productivity, invasive bivalves, marsh processes, contaminant dynamics, and fish populations respond?
    Science topics None specified
    Updated April 29, 2022
  • Title

    Quantifying the contribution of tidal flow variations to survival of juvenile Chinook salmon

    Lead U.S. Geological Survey [USGS]
    Description The purpose of this project is to quantify how tides in the Delta influence survival of juvenile salmon. Juvenile salmon survival increases when there is more flow and the river is less tidally influenced. We hypothesize that the increase in survival is because of reduced travel times causing less exposure to predators. This project will test this hypothesis using multiple models including ones that can predict how management actions that modify tidal patterns affect juvenile salmon survival.
    Science topics Chinook Salmon, Salmon migration, Surface water / flow, Tides, Water management
    Updated January 29, 2024
  • Title

    Assessing Sediment Nutrient Storage and Release in the Delta: Linking Benthic Nutrient Cycling to Resotration, Aquatic Vegetation, Phytoplankton Productivity, and Harmful Algal Blooms

    Lead U.S. Geological Survey [USGS]
    Description Nutrients in sediment play a large role in influencing food webs, harmful algal blooms, aquatic vegetation, and drinking water quality. This study will investigate the amount, types, and dynamics of nutrients in Delta sediments. It will also examine sediment microbial communities that mediate these processes. Results of this study will help determine how the planned reduction in nutrient inputs to the Delta will effect sediment nutrients and microbial communities following the upgrade of the Sacramento Regional County Sanitation District’s wastewater treatment plant. Data will also inform how wetland restoration and invasive aquatic vegetation influence sediment nutrients and microbial communities. These data will contribute to improving computer models that inform large-scale nutrient management actions.
    Science topics Aquatic vegetation, Benthic, Cyanobacteria, Harmful algal blooms HAB, Nitrogen, Nitrogen / ammonia, Nutrients, Phytoplankton, Sediments
    Updated November 28, 2022
  • Title

    Low-Cost Satellite Remote Sensing of the Sacramento-San Joaquin Delta to Enhance Mapping for Invasive and Native Aquatic Vegetation

    Lead University of California - Davis [UC Davis]
    Description Invasive aquatic vegetation (IAV) acts as an ecosystem engineer by changing habitat conditions and water quality. This negatively affects the survival of native species. Over the past 15 years, IAV has more than doubled its footprint in the Sacramento-San Joaquin Delta waterways. The State of California spends millions of dollars each year to control IAV in the Delta-Suisun region and costs are likely to continue to rise. Gaining a better understanding of the spread, life history characteristics, and potential vulnerabilities of these species can lead to more effective control strategies. The recent launch of the Sentinel-2 satellite can fill temporal gaps left by annual airborne surveys. This study will create a data pipeline for sustained, low-cost satellite-based monitoring of aquatic and marsh vegetation year-round. To quantify one of the Delta Plan performance measures, the time and degree of floodplain inundation for the Yolo Bypass will be measured. This study will result in new metrics to measure progress toward habitat goals in several restoration sites.
    Science topics Aquatic vegetation, Invasive / non native species
    Updated November 18, 2022
  • Title

    Resolving Contradictions in Foodweb Support for Native Pelagic Fishes

    Lead San Francisco State University [SFSU]
    Description Much research in the Delta has focused on foodweb dynamics, stimulated by evidence that low productivity of plankton is linked to declines in several fish species including the endangered delta smelt. Pseudodiaptomus forbesi is the most abundant copepod (small crustaceans) in the Delta in summer. It is an important food source for many fishes and makes up about half of the food of delta smelt. This study focuses on the feeding, reproduction, and growth of copepods as essential foodweb support for fishes. This work investigates four diverse habitats including two open-water channels and two shallow habitats. The researchers will measure copepods´ feeding rates on microscopic plants and animals, and relate feeding to their rates of growth and reproduction. Computer models will be used to estimate their movement and death rates. These results will show the sources of nutrition used for growth and reproduction of these key organisms. Results will inform how food webs respond to large scale changes in the Delta ecosystem, for example, restoration and the Sacramento wastewater treatment plant upgrade.
    Science topics None specified
    Updated April 29, 2022
  • Title

    Next Generation Multi-Hazard Levee Risk Assessment

    Lead University of California - Los Angeles [UCLA]
    Description In June 2004, a 350-foot levee section gave way west of Stockton, flooding crops and more than a dozen homes, and challenging state officials to protect the state's water supply. What is the risk of that happening again somewhere in the Delta? In light of agricultural fields sinking, the sea level rising, more frequent and severe floods occurring, and earthquakes looming, improvements are estimated to cost $3.8 - $4.3 billion over the next few decades. This study combines 3-D representations with information on the levee’s structure to analyze how different levees respond to floods, sea level rise, and earthquakes. State officials released the last Delta Risk Management Strategy a decade ago. Since then, scientists have collected significant amounts of data and have developed new procedures to compute the risk of failure. This work will produce new Delta-wide data sets important for characterizing the hazards coming from floods and earthquakes. It will also develop the best method to conduct levee hazard assessments. Applying this new method will ensure wise investments and effective threat mitigation Delta-wide.
    Science topics None specified
    Updated April 29, 2022
  • Title

    Tidal Wetland Restoration in the Bay-Delta Region: Developing Tools to Measure Carbon Sequestration, Subsidence Reversal, and Climate Resiliance 2021

    Lead California State University [CSU]
    Description Tidal marshes are important ecosystems in the San Francisco-Bay Delta. They remove carbon from the atmosphere, build up soils that buffer our communities from sea level rise, mitigate excessive nutrients (like nitrogen), and provide critical habitat and food resources for a diversity of species. It is difficult to predict how tidal marshes change naturally over time versus as a response to climate change, restoration and water quality changes. This project provides the first ever multi-year dataset of the complete carbon budget of a tidal marsh. This dataset will be used to predict seasonal and annual carbon budgets in tidal marshes over a range of salinities. The model will assess the sustainability of existing and potential restored tidal wetland benefits over the next 100 years using remote sensing data. The model will be an open-source tool designed for use by wetland managers and decision makers in the Bay-Delta region. This project supports ongoing initiatives to restore tidal wetlands in the Delta and our ability to manage them in a changing world.
    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

    Life History Variation in Steelhead Trout and the Implications for Water Management

    Lead University of California - Santa Cruz [UCSC]
    Description The purpose of this project is to explore the ways in which different stream hydrology and temperature can affect the growth and maturation of steelhead trout. Model examination will incude various stream flow management regimes may affect trout population dynamics region-wide.
    Science topics Steelhead Trout
    Updated April 29, 2022
  • Title

    Recreational Hunting as an Ecosystem Service of Restoration in the Bay-Delta Watershed

    Lead Santa Clara University
    Description Ecological restoration in the Bay-Delta watershed provides increased access to hunting opportunities for recreational hunters in the region in addition to benefitting native flora and fauna. While increased hunting is not always considered an economic benefit, it is a dividend from investments in habitat restoration. This research will quantify in dollars the economic impact of restoring sites and opening them for hunting. The study will survey members of the public at restored sites in the Bay-Delta and Sacramento River regions that have resulted in new and/or improved hunting access. In addition to the economic analysis, the survey will shed light on two other issues: 1) whether there is a tradeoff among recreational usage, carbon storage, and habitat quality for restored sites, and 2) whether current users perceive an unmet need for recreational access in the region. These analyses will be useful in explaining multi-benefit restoration projects to stakeholders and policymakers, and informative to future decision-making.
    Science topics Hunting
    Updated December 7, 2022
  • Title

    Evaluating Juvenile Salmonid Behavioral Responses to Hydrodynamic Conditions in the Sacramento-San Joaquin Delta

    Lead State Water Contractors [SWC]
    Description This study combines detailed model predictions with salmonid tracking data to inform how river flows affect steelhead movement through the Delta. This project leverages an existing 6-year data set to support analysis of salmonid behavioral responses across a broad range of water years. The study will evaluate behavior relative to flow under existing regulatory requirements (Old and Middle River Flow and the Inflow to Export ratio), evaluate five new potential water management metrics identified by the Collaborative Adaptive Management Team Salmonid Scoping Team, and improve the understanding of what conditions affect survival.
    Science topics None specified
    Updated April 29, 2022
  • Title

    Impact of Temperature and Contaminants on Chinook Salmon Survival: A Multi-Stressor Approach

    Lead National Marine Fisheries Service [NMFS]
    Description The decline of native salmon species has resulted in their protection under the U.S. Endangered Species Act and the California Endangered Species Act. Disease and predation are primary drivers of mortality as salmon migrate. Multiple stressors, such as exposure to contaminants and elevated temperature, can impact rates of disease and predation of salmon as they migrate to the ocean. This study examines how contaminant exposures at different temperatures affects salmon health. Specifically, the study investigates the sensitivity of salmon to a contaminant mixture of bifenthrin (a pyrethoid pesticide) and triclosan (an antibacterial added to personal care products). Both contaminants can alter fish swimming behavior and critical physiological functions. Similarly, temperature stress can impact fish physiology and behavior, as well as exacerbate the adverse effects of contaminants.
    Science topics None specified
    Updated April 29, 2022
  • Title

    Synchrony of Native Fish Movements: Synthesis Science Towards Adaptive Water Management in the Central Valley (FishSync)

    Lead University of California - Davis [UC Davis]
    Description Salmon and other native California fishes are in decline and increasingly targeted for enhanced conservation. Acoustic telemetry technologies have emerged, allowing researchers to track fish routes through the Central Valley. Yet while the use of acoustic telemetry has widened, little synthesis has occurred on the large, growing, and expensive datasets that already exist. The main goal of the project is to conduct a synthesis study of existing and high priority telemetry datasets for native and non-native fishes in the Central Valley. Using synchrony of movement rates, through space and time, we will develop a novel behavior-based statistical framework to gain understanding into the environmental conditions that promote movement/passage of diverse native fishes in the Central Valley. The project includes a Technical Advisory Group, composed of members of multiple conservation teams. The group will inform each step of study, strengthen syntheses, and enable rapid communication of results to decision makers. In total, the project will analyze 10 to 15 high-quality telemetry datasets encompassing a range of native fishes and life stages. This synthesis will yield major insights into water management practices that could help improve survival of native fish.
    Science topics Chinook Salmon, Fish, Salmon migration, Steelhead Trout, Sturgeon, White Sturgeon
    Updated December 4, 2022
  • Title

    An Evaluation of Sublethal and Latent Pyrethroid Toxicity Across a Salinity Gradient in Two Delta Fish Species

    Lead Oregon State University
    Description Pyrethroids are a type of insecticide frequently detected in the San Francisco Bay and Delta (SFBD). They are highly toxic to fishes and may contribute to their decline. The Central Valley Water Resources Control Board has adopted regulations for many pyrethroids. These concentration goals for Delta surface waters are quite stringent. However, they do not take into account non-lethal effects in fishes, particularly during the early life stages and at the salinity conditions we see in the SFBD. Understanding non-lethal effects in fish is vital to influencing population health. This study investigates pyrethroid toxicity on Delta smelt and Inland Silverside embryos, while accounting for changing SFBD salinity and other factors such as sediment. Results will inform the development of pesticide regulation criteria and control efforts, furthering the protection of SFBD fishes.
    Science topics None specified
    Updated April 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

    Integrated Science and Management of Nutrient, Salt, and Mercury Export from San Joaquin River Wetland Tributaries to the Delta

    Lead University of California - Merced [UC Merced]
    Description Mercury, salinity, and nutrients such as nitrogen and phosphorus are major contaminants of concern and are an understudied source of water quality impairment to the Delta. This study will (1) examine seasonal variation and transfer of salt, nutrients, and mercury out of managed wetlands;(2) establish and verify whether other routinely monitored water components can serve as reliable alternatives (proxies) for detecting mercury and nutrients;(3) integrate monitoring data and proxy relationships to estimate levels of contaminants;and (4) develop science-based strategies for adaptive co-management of salt, nutrients, and mercury from seasonal wetlands to improve water quality in the Delta. Outcomes from this study will provide improved best practices and guidelines for management of salt, nutrients, and mercury in wetlands. Results will also address key knowledge gaps identified in the Delta Nutrient Research Plan and provide support for the Delta Mercury Control Plan.
    Science topics Nutrients, Salinity, Hg and methyl mercury
    Updated April 29, 2022
  • Title

    Improving Green Sturgeon Population and Migration Monitoring

    Lead University of California - Santa Cruz [UCSC]
    Description Green sturgeon is a listed species under the federal Endangered Species Act. This project supports the recovery and management of the southern distinct population segment of green sturgeon by improving population and migration monitoring. Improved monitoring is recommended in multiple initiatives to help protect this species, such as the Green Sturgeon Recovery Plan. There is some uncertainty on whether the most appropriate green sturgeon monitoring techniques are being used. This project compares the different estimation and monitoring techniques to identify the superior protocol. To compare the effectiveness of different techniques, scientists will monitor green sturgeon in the Sacramento River using sonar technology. Monitoring data will be used to estimate the population size and death rates due to by-catch. This project will also review and synthesize past acoustic telemetry data to determine if the data can be modeled to improve population size estimates.
    Science topics Green sturgeon
    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

    CASCaDE: Computational Asessments of Scenarios of Change for the Delta Ecosystem

    Lead U.S. Geological Survey [USGS]
    Description Agencies of the CALFED Bay-Delta Authority (CBDA) face tough decisions as they search for strategies to meet their programmatic goals of stabilizing water supplies in California, providing safe drinking water to a growing population, and sustaining diverse populations of native species and their supporting ecosystem functions. The challenge of finding balanced solutions to these goals is daunting because of the enormous complexity of the San Francisco Bay-Delta system and its tributary rivers and their watersheds. The challenge grows as we consider the additional layer of complexity imposed by the certainty that all the key forces that drive dynamics of this ecosystem (climate, hydrology, water management, land use, sea level) will change significantly in future decades. This proposal describes a model-based approach for developing a long view of the Bay-Delta-River-Watershed system. The long view will be developed through simulations with linked models to project changes under a range of plausible scenarios of global warming, hydrologic responses, land-use change, reconfigurations of within-Delta habitats, and sea level rise. Our goals are to develop and apply a model-based approach of ecological forecasting to project future states of the Delta ecosystem under prescribed scenarios of change, and to communicate the outcomes of those scenarios to resource managers facing the daunting challenge of meeting CBDP goals in a continually changing world.
    Science topics None specified
    Updated November 18, 2022
  • Title

    Phytoplankton and cyanobacteria growth and response to stressors

    Lead University of California - Davis [UC Davis]
    Description Pesticide and nutrient inputs from human activities are present in the Sacramenot-San Joaquin Bay-Delta, but the impact of these stressors together on algae is not well known. This research will examine the impacts of herbicides and nutrients on the growth and stress responses of phytoplankton and cyanobacteria present in the San Francisco Estuary. The algae in the delta are diverse with critical ecological effects, ranging from toxin-producing cyanobacteria that form hazardous algal blooms to benthic diatoms and green algae that make up the bulk of the aquatic food web. Contaminants and herbicides can cause changes in algae cellular health which may impact population growth. Understanding algal sub-lethal stress responses will improve our understanding of stressors on the bay-delta food web and bloom formation.
    Science topics Phytoplankton, Cyanobacteria
    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

    Estuarine fish community responses to climate, flow, and habitat

    Lead University of California - Berkeley [UC Berkeley]
    Description The goal of this research is to better understand how climate change will affect fishes with different life histories and habitat associations across the San Francisco Estuary. Existing datasets will be incorporated in synthetic analyses and cutting-edge statistical models to identify fish community responses to climate, flows, and habitats along the estuarine salinity gradient. This synthesis-science project will use rich long-term datasets that have been collected by Bay-Delta researchers for decades that will then be analyzed in a reproducible and open science framework. It will also support efforts by the Interagency Ecological Program’s Climate Change Project Work Team.
    Science topics Estuaries
    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

    The effect of temperature on predation of juvenile salmonids

    Lead University of California - Davis [UC Davis]
    Description This study will investigate fish swim performance in response to temperature, using salmon and two of its known predators: largemouth bass and Sacramento pikeminnow. The researcher will assess swim performance metrics and predation risk inside and outside the ideal thermal range of each species to determine if a temperature advantage predicts salmon survival in predation scenarios. This project’s results will provide a mechanistic understanding of how temperature stress may influence mortality risk of juvenile Chinook salmon through predation, which will offer a more holistic perspective on the management of this species
    Science topics Temperature
    Updated April 29, 2022
  • Title

    Pesticide risk analyses and management actions, chemical fate and transport

    Lead University of California - Santa Barbara [UCSB]
    Description This project work will model the risk of pesticide pollution in 225 sub-catchments of the Sacramento-San Joaquin Bay-Delta. The model will account for water management practices, land use, pesticide use rates, and cumulative pesticide stress. Additionally, this work will produce a web-based tool to simulate current and future risks based on the ranking of primary sources of pesticide contribution. This work will provide a framework to predict risk from chemical stressors. Specific objectives are: (1) enhanced pro-active chemical risk assessment, (2) creation of a tool which enables science-based chemical use decisions, (3) improved risk screening for vulnerable areas, and (4) identification of adverse effects of current and future chemical use strategies.
    Science topics Herbicides
    Updated April 29, 2022
  • Title

    Using existing datasets to understand multi-scale changes in and controls on biogeochemistry in the SF Bay-Delta

    Lead University of California - Santa Cruz [UCSC]
    Description In collaboration with the United States Geological Survey, this research will explore temporal and spatial variability of carbon and nitrogen biogeochemistry across the San Francisco Bay-Delta. This science synthesis will capitalize on existing multi-year isotope datasets to gain new insights useful for understanding future changes in the system. The results generated from this two-year data synthesis project will be useful for improving our current understanding of factors driving changes in SF Bay-Delta biogeochemical processes. Results will also be informative for understanding the imminent changes coming to the from the Sacramento Regional Wastewater Treatment Plant upgrade.
    Science topics Nitrogen
    Updated November 17, 2022
  • Title

    Nitrogen cycling and ecosystem metabolism before and after regulatory action

    Lead Stanford University
    Description This project focuses on nitrogen and carbon cycling within the Bay-Delta, both before and after planned 2021 upgrades to the Sacramento Regional Wastewater Treatment Plant (SRWTP). We will measure in situ benthic nitrate (NO3- ) and oxygen (O2) fluxes using a new non-invasive technique, which provides high frequency continuous data over a much larger sediment surface area than traditional methods. The SRTWP currently represents one of the largest point sources of nitrogen to the Bay-Delta, with the upgrades projected to cut nitrogen outputs from the plant by ~65%. This project will help assess the efficacy of this major management action and our results will add to biogeochemical models for the Bay-Delta.
    Science topics Nitrogen / ammonia
    Updated April 29, 2022
  • Title

    Understanding the Scale and Mechanisms of Connectivity between Splittail Populations and the Implications for Management

    Lead U.S. Bureau of Reclamation [USBR]
    Description Our proposal seeks to add four elements, telemetry, genetics, physiology, and modeling, to an existing research effort on splittail. The study addresses the hypothesis that there is no difference in population dynamics between the two distinct splittail populations. To address this hypothesis we are conducting a collaborative, interdisciplinary study that includes an intensive field effort combined with state-of-the-art laboratory tools that can determine the natal origins, historical habitat use, feeding, and general health of adult splittail. With this proposal we seek to leverage additional funds that were not previously available to add the four new elements. The telemetry component will take advantage of the expansive existing array of receivers deployed in the estuary to evaluate the movements and migration of splittail. The genetic component will provide a precise means to assign individuals to their respective population, determine sex ratios, and to estimate the effective size of the populations. The physiology component will determine if the newly discovered Petaluma/Napa population of splittail exhibits different requirements and tolerances than the Central Valley population. The modeling component will apply the cumulative information gained by the overall study to evaluate the sensitivity of splittail persistence to demographic variability in population dynamics. This work will directly address the Priority Research Topics presented in the PSP.
    Science topics Sacramento Splittail
    Updated April 29, 2022
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