Research Awards

2025 Awards

The 2025 Delta Research Awards provide $5.9 million to fund eight projects that respond to one or more of the priority Science Action(s) identified in the 2022-2026 Science Action Agenda. Following the proposal reviews, selection process, and coordination with the Council, the State Water Contractors provided funding support for the projects; “Fit for the Wild: Cultivating Release-Ready Delta Smelt in Impoundments” and “Uncovering Genetic and Life History Resilience in Spring-Run Chinook Salmon,” bringing the funding total to $7.8 million. The projects cover a range of topics, including harmful algal blooms, eco-cultural restoration, Tribal Knowledge, subsidence, hydrology, acoustic telemetry, endangered species, and more.

Project Title	Description	Lead Principal Investigator
Advancing a Collaboratory for Equitable Stewardship of the Sacramento-San Joaquin River Delta Watershed	The Delta faces habitat loss, declining species, and water quality issues. This project aims to include marginalized communities in decision-making by integrating diverse knowledge sources, including indigenous and local knowledge, into management decisions to support ecological resilience and inclusive stewardship. The project will use innovative models and interactive platforms to bring together various perspectives for better decision-making and resource management. The project aims to integrate an understanding of the Delta waterways' social-ecological uses and diverse values to inform equitable solutions to Delta management challenges, promote public engagement, and support equitable stewardship of the Delta’s vast resources. * Funded by the Delta Stewardship Council	Theodore Grantham, University of California, Berkeley
Eco-Cultural Renewal of Delta Tule Landscapes	The Eco-Cultural Renewal of Delta Tule Landscapes is a collaborative project between the San Francisco Estuary Institute (SFEI) and two Delta area Tribes, the Shingle Springs Band of Miwok Indians and the Koy’o Land Conservancy. The project aims to interweave Traditional Ecological Knowledge (TEK) with Delta science, management, and policies to make these processes more inclusive. Data will be collected through interviews, literature reviews, and a Tribal workshop to guide future management efforts. The project addresses the need for better collaboration between Delta agencies and Tribes while supporting effective and equitable management by including Tribal perspectives in decision-making. * Funded by the Delta Stewardship Council	April Robinson, San Francisco Estuary Institute Aquatic Science Center
Understanding Social-Environmental Interactions in Suisun-Delta Tidal Marsh Restoration	Tidal marsh restoration in areas like Suisun Marsh and the Sacramento-San Joaquin Delta is crucial for ecosystem services, especially in response to climate-driven sea level rise. However, knowledge gaps exist in how communities perceive and interact with restored habitats. This project seeks to integrate ecological data with social metrics to address environmental justice concerns, enhance public engagement, and improve restoration outcomes. By understanding how communities value and use restored habitats, the project will provide insights to inform management, planning, and policy decisions. * Funded by the Delta Stewardship Council	Stuart Siegel, San Francisco State University; San Francisco Bay National Estuarine Research Reserve
Optimizing Monitoring Tools for Cyanobacterial Harmful Blooms in the Sacramento-San Joaquin River Delta	Harmful algal blooms (HABs) of Microcystis, a toxin-producing cyanobacteria, have increased in the Delta due to warming temperatures, drought, and reduced water flow. The Microcystis Visual Index (MVI) helps assess bloom density but has limitations. This project aims to improve MVI by developing an image classification model to link MVI rankings to Microcystis biomass and toxicity, enhancing our understanding of health risks. It will improve monitoring of Microcystis density and microcystin concentrations, a harmful toxin created by cyanobacteria that can contaminate drinking water, and it will create user-friendly tools for better monitoring HABs in the Delta. * Funded by the Delta Stewardship Council	Holly Bowers, Moss Landing Laboratories
Analyzing Flow Regime Effects on Adult Green Sturgeon Migration in Central California Rivers: Science and Policy	There are two populations of green sturgeon, with the Southern Distinct Population Segment (sDPS) found in the Sacramento-San Joaquin Delta. This population is vulnerable to habitat loss and water management impacts, such as altered flow and temperature. This project aims to use fish movement data to develop an individual-based model (IBM) that simulates green sturgeon migration and evaluates the effects of water management and climate change. By understanding how water management practices impact the spawning and survival of the threatened sDPS green sturgeon, the project will provide tools for conservation and policy efforts. It will help managers and policymakers assess how water management and climate changes affect green sturgeon populations. * Funded by the Delta Stewardship Council	Karrigan Bӧrk, University of California, Davis
From Source to Sea: Building an Integrated Cross-Cultural Vision of Sierra Headwaters and Delta Resilience	The impact of climate change on the Sierra Nevada headwaters, which supply water to the Sacramento-San Joaquin Delta, is not well understood. This project combines climate change modeling with tribal knowledge to develop a framework for increasing climate resilience. It will integrate data on benthic macroinvertebrates (small, bottom-dwelling organisms often used as water quality indicators), hydrology, climate, and Traditional Ecological Knowledge (TEK) to create tools for predicting ecosystem resilience and prioritizing conservation efforts. Integrating TEK into climate change modeling will close knowledge gaps, include indigenous perspectives, and help implement management strategies to enhance climate resilience. * Funded by the Delta Stewardship Council	Jeffrey Lauder, Sierra Streams Institute
Leveraging Citizen Science to Study Sturgeon Mortality in the San Francisco Estuary	The San Francisco Bay-Delta Estuary is home to both the white sturgeon and the federally threatened green sturgeon. White sturgeon has recently been designated candidate species under the California Endangered Species Act, prompting the California Department of Fish and Wildlife (CDFW) to evaluate their status. Key threats include harmful algal blooms (HABs) and vessel strikes, particularly in the Carquinez Strait, a critical sturgeon migratory corridor. This study will use citizen science to gather data supporting CDFW’s evaluation and guide management strategies to help recover adult green and white sturgeon populations. * Funded by the Delta Stewardship Council	Benjamin Burford, University of California Santa Cruz
Improving Subsidence and Carbon Emissions Modeling	The oxidation of Delta organic soil causes subsidence, threatening infrastructure, water systems, biodiversity, and agriculture while releasing about 1.2 million metric tons of CO2 annually. The SUBCALC model is a tool that estimates subsidence rates and CO2 emissions, aiding carbon offset validation and land-use decisions. The tool helps landowners convert drained farmland into wetlands, reducing subsidence and flood risks. Ongoing research uses LiDAR and UAVSAR remote sensing data to improve SUBCALC’s accuracy. The improved model will better predict subsidence, protect infrastructure, reduce flood risks, support carbon market participation, and inform sustainable land management strategies. * Funded by the Delta Stewardship Council	Steven Deverel, HydroFocus Inc.
Fit for the Wild: Cultivating Release-Ready Delta Smelt in Impoundments	The Delta Smelt is a small fish found only in the San Francisco Bay-Delta that was once abundant but now critically endangered. Despite ongoing conservation efforts, captive-bred smelt struggle to survive when released into the wild. This project will explore using natural impoundments (enclosed environments that mimic wild conditions) to improve rearing methods. Researchers will compare the fitness of smelt raised in impoundments compared to those raised in traditional hatcheries. The goal of this project is to raise Delta Smelt so that it can better adapt to survive in the wild, which could contribute to Delta Smelt’s long-term survival. * Funded by the State Water Contractors	Florian Mauduit, University of California, Davis
Uncovering Genetic and Life History Resilience in Spring-Run Chinook Salmon	California's spring-run Chinook salmon, a critically important species for freshwater ecosystems and tribal communities, faces a high risk of extinction despite their historical abundance. This project aims to develop an innovative toolbox using genetic and isotopic markers to assess the diversity of Central Valley spring-run Chinook salmon populations. Researchers will analyze adult spawners across the population range by examining Chinook salmon DNA, ear bones of the fish, and chemical markers in fisheye lenses to study migratory strategies, habitat use, and age structure. The goal is to provide insights to guide recovery efforts, support sustainable populations, and inform restoration strategies in the face of environmental challenges. * Funded by the State Water Contractors	Flora Cordoleani, University of California, Santa Cruz; NOAA, Southwest Fisheries Science Center

2021 Awards

Over $9.6 million of combined funds from the Delta Science Program and the U.S. Bureau of Reclamation were awarded to 16 high-priority research projects (see table below). Following the proposal reviews, selection process, and coordination with the Council, the State Water Contractors provided funding support for the project; “How Delta food webs have changed: integrating detrital material into the Delta food web puzzle,” bringing the funding total to over $10 million.

All projects address critical biophysical and social science knowledge gaps in the Delta identified in the 2017-2021 Science Action Agenda and by the Sacramento River Science Partnership. Of the funded projects, two were focused on Integrated Socio-Ecological Systems (ISES) research, a new project category for this solicitation that meaningfully integrates social and natural sciences to build comprehensive knowledge on a topic.

To showcase these projects, the Delta Science Program hosted a series of seminars with presentations by the funded researchers. Those recordings are available on the Council’s YouTube playlist featuring our Delta Research Award Seminar Series. In these videos, researchers share findings from their projects, including advancements, challenges, and the impact their work is having on closing key knowledge gaps in Delta science and informing science-based management of the Delta. We encourage you to explore the YouTube playlist to catch up on outcomes from the 2020-2021 Delta Research Awards.

Please email archives@deltacouncil.ca.gov with questions about access to products.

Project Title	Description	Lead Principal Investigator	Products
Addressing CyanoHABs as a threat to water and air quality in the San Francisco Bay-Delta, CA	High concentrations of the toxin microcystin are linked to the increased occurrence of cyanoHABs (harmful algal blooms that produce toxins) and present a public health concern for communities in the Delta. Recent findings suggest that cyanoHABs threaten air and water quality via emissions of spray aerosols carrying algal cells and toxins. This study generated high-resolution measurements of cyanoHAB toxins and DNA in the Delta airshed to inform human exposure guidelines for airborne cyanoHAB toxins and bloom mitigation policy in the region. *Funded by the Delta Stewardship Council	Hans Paerl, University of North Carolina, Chapel Hill	Info Sheet
Harmful algal blooms and cyanotoxins in the Delta: occurrence, distribution, trends, and environmental drivers	A major impediment to improved understanding and prediction of cyanoHABs in the Delta is the need for cyanoHAB data collected across space and time. To address this data gap, this study added cyanotoxin sampling to five existing real-time water quality monitoring stations in the Delta. Additionally, two stations were equipped with sensors that continuously measure the abundance of four phytoplankton groups. This data identified temporal patterns and informed future monitoring of cyanoHABs and cyanotoxins. *Funded by the Delta Stewardship Council	Tamara Kraus, U.S. Geological Survey	Info Sheet
Assessing sea-level rise and flooding changes in the Sacramento/San Joaquin Delta using historical water-level records	In the Delta, sea level rises, land sinks, river flows decrease, and tides change. This project will recover, digitize, and analyze over 1,300 station years of ‘lost-and-forgotten’ water level records collected between 1857 and 1982. These measurements, augmented by modern data, will determine tidal and sea level trends and characterize ‘hotspots’ of habitat and flood risk sensitivity. The results may be useful for focusing future scientific and management priorities, protecting the environment, managing flood risk, and enhancing community resilience to climate change. *Funded by the Delta Stewardship Council	Stefan Talke, California Polytechnic State University, San Luis Obispo	Info Sheet
Towards quantifying the effects of climate change and sea-level rise on carbon accretion by tidal and non-tidal wetlands exposed to a range of salinity along the San Francisco Bay Estuary and Delta	Tidal wetlands that ring the Delta have great potential to remove carbon dioxide— the greenhouse gas responsible for climate change and sea-level rise—from the atmosphere and to protect shorelines from rising sea levels. This study set out to understand how effectively and quickly restored wetlands bury carbon in soils and the degree to which flooded wetlands may produce methane, a potent greenhouse gas. The project team measured carbon dioxide and methane fluxes into and out of the wetlands to assess carbon sequestration across a network of tidal and non-tidal wetlands differing in age and salinity. They examined variability across the Delta using this information and remote sensing products. *Funded by the Delta Stewardship Council	Dennis Baldocchi, University of California, Berkeley Biometeorology Lab	Info Sheet
The effects of climate change on the life history of spring-run Chinook through time	Climate change is transforming California and is threatening already vulnerable salmon populations. This project will use archival tissues (otolith ear stones) from modern and historical spring-run Chinook Salmon to understand how migration timing and habitat use shifts allowed salmon to cope with highly variable environmental conditions. We will learn how salmon responded to the recent drought and flood periods (2012-2020), the California Gold Rush Period (~1835-1870), the Little Ice Age (~1560-1780), and the Megadrought Period (~1200-1410). This effort will provide the insights needed for developing climate-adapted conservation actions to support salmon into the future. *Funded by the Delta Stewardship Council and the US Bureau of Reclamation	Malte Willmes, University of California, Santa Cruz	Info Sheet
Understanding within- and between-basin migration in White Sturgeon: A synthesis of more than 10 years of acoustic tagging data	White Sturgeon is a species of conservation concern in California. However, the scope and variability of White Sturgeon movements in the Delta system between river basins remain unknown despite the existence of over a decade’s worth of acoustic telemetry data in the region. This project’s objective is to combine and synthesize these existing datasets to address high-priority research areas for the management of White Sturgeon in the Delta system, including spawning periodicity, the onset of upstream migration movement, and the scope and variability of inter-basin movements of White Sturgeon. *Funded by the Delta Stewardship Council and US Bureau of Reclamation	Myfanwy Johnston, Cramer Fish Sciences	Info Sheet
Regulation of controls of cold water through the Temperature Control Device of the Shasta Dam as a means of supporting downstream fish populations	The Temperature Control Device (TCD) at Shasta Dam provides a means for the U.S. Bureau of Reclamation to selectively withdraw water from different depths and temperatures to manage cold water releases to downstream river reaches during the spring, summer, and fall. Cold-water pool management, particularly during low water years, is essential for downstream winter-run Chinook salmon spawning and rearing. The way the TCD operates day-to-day for different gate openings, powerhouse operations, and thermal conditions within the reservoir is poorly understood. This work will build a flow model to optimize the performance of the existing infrastructure to protect downstream fisheries, enabling more informed operation of the TCD. *Funded by the US Bureau of Reclamation	Alexander Forrest, University of California, Davis	Info Sheet
Estimating juvenile production and run timing of spring Chinook salmon leaving the Delta	The estimated number of young salmon that leave the upper watershed every year, or the “juvenile production estimate,” has been highlighted as a critical data gap that could otherwise be used to inform population demographics, parameterize life cycle models, and provide population-level criteria for managing take of federally threatened spring-run and endangered winter-run Chinook salmon at the state and federal water projects. In response to this data gap, this project aims to estimate the abundance and run timing of juvenile spring-run Chinook salmon leaving the Delta at Chipps Island by leveraging two existing studies that use the latest genetic and acoustic telemetry technology advances. *Funded by the Delta Stewardship Council and US Bureau of Reclamation	Russell Perry, U.S. Geological Survey, Western Fisheries Research Center	Info Sheet
Comparing the impact of predation on the outmigration mortality of all Central Valley salmon ecotypes relative to other habitat-related covariates	This study analyzed acoustic telemetry data for the four runs or “ecotypes” of Chinook salmon (Oncorhynchus tshawytscha) in California’s Sacramento River (fall, late-fall, winter, and spring) to determine the primary factors for each run that affect mortality of juveniles migrating to the ocean. The project team developed models of juvenile salmon survival to examine the relative influence of flow and predation on survival through the Sacramento River, including indications of mortality hot spots, where predation may claim the most juvenile salmon before they enter the ocean. *Funded by the US Bureau of Reclamation	Mark Henderson, Rubenstein School of Environment and Natural Resources, University of Vermont; USGS, Vermont Cooperative Fish and Wildlife Research Unit	Info Sheet
Reorienting to recovery: Developing an inclusive, landscape-scale process for Central Valley Salmonids, prioritizing actions and investments to achieve recovery and minimize community and economic impact	Salmon of California’s Central Valley are culturally and ecologically valuable but are subject to numerous stressors. This study will use sociological and ecological methodologies to develop an integrated, collective, and strategic approach for recovering Central Valley salmonid populations. The project will do this by leveraging existing collaborative efforts and decision-support tools to create a shared vision and a common set of scientifically-based priorities for action that are both implementable and impactful. *ISES; Funded by the Delta Stewardship Council and US Bureau of Reclamation	Rene Henery, Trout Unlimited	Info Sheet
Standard operating procedure for diagnosing and addressing predator detections in salmon telemetry data	Predation of tagged fish (i.e., consumption of tagged fishes by predators) complicates the analysis of juvenile salmon telemetry studies and can bias results, delay timely reporting, and prevent effective data synthesis. This project seeks to address these issues by characterizing predatory fish movement patterns from existing telemetry data in the Delta, developing a standard operating procedure for diagnosing and handling detections of predated tags in salmon telemetry studies, and implementing the recommendations in an R software package that includes code, a “library” of expected predator behaviors, and example vignettes. *Funded by the Delta Stewardship Council and US Bureau of Reclamation	Rebecca Buchanan, University of Washington	Info Sheet
Suisun landscapes: historical ecology, functional metrics, and community priorities for landscape planning	Suisun Marsh faces changes to its ecological, social, and economic systems due to the interacting impacts of climate change and land and water management. Sustaining a functioning marsh that supports fish, waterfowl, recreation, and other benefits requires thoughtful planning and coordination among landowners, resource managers, and other stakeholders. To support these efforts, Suisun Landscapes will develop a synthetic and inclusive set of resources for conservation planners and managers that describe the Marsh’s historical ecology, the drivers, pathways, and impacts of change over time, and community uses and priorities. Resources will include maps, quantitative metrics, written reports, and tools for scenario planning. *Funded by the Delta Stewardship Council	Letitia Grenier, San Francisco Estuary Institute, Aquatic Science Center	Info Sheet
Integrating social and ecological research to control invasive species: fostering collective action among private and public stakeholders	Suisun Marsh, a large area of wetlands, supports a variety of birds, fish, invertebrates, and plants and provides recreation opportunities for hunters, fishers, birdwatchers, and boaters. The area has been invaded by nonnative, invasive Phragmites australis, a tall reed that grows in dense stands, impedes navigation, reduces fish and wildlife movements, decreases biodiversity, and creates fire hazards. Phragmites has spread rapidly over the last 25 years, including in recently restored tidal wetlands. This project will study social, cultural, and ecological factors that affect invasive species control, combining natural and social science data to develop a durable integrated control plan for Phragmites. *ISES; *Funded by the Delta Stewardship Council	John Takekawa, Suisun Resource Conservation District	Info Sheet
How Delta food webs have changed: integrating detrital material into the Delta food web puzzle	A healthy Delta ecosystem depends on healthy fish, and they depend on increasingly scarce zooplankton resources. Thus, this project focused on different food sources for zooplankton of varying quality, including known sources like phytoplankton, but also plant (detrital) particles, which have only recently been identified as a significant zooplankton food source in the Delta. This project identified the source of particle types beneficial to zooplankton in the Delta by coupling laboratory analyses of food quality with boat sensor measurements, thereby providing important tools for guiding management decisions to increase those beneficial particles. *Funded by the Delta Stewardship Council and State Water Contractors	Peter Hernes, University of California, Davis	Info Sheet
Non-invasive environmental DNA monitoring to support tidal wetland restoration	Extensive tidal wetland restorations are ongoing in the Delta. To understand which species use these habitats, this project will use environmental DNA (eDNA) methods that indirectly detect species presence via DNA shed in the environment. In parallel with existing monitoring programs that use nets to catch and identify fish, this project will collect non-invasive water samples and perform eDNA assays to determine the presence or absence of fish and potentially other organisms. Successful completion of this project will establish eDNA monitoring as a complementary, cost-effective tool to help resource managers evaluate the success of restoration efforts. *Funded by the Delta Stewardship Council and US Bureau of Reclamation	Raman Nagarajan, University of California, Davis	Info Sheet
From microbes to zooplankton, what defines a beneficial wetland?	Massive wetland restoration efforts are underway in the Delta to help our declining aquatic species. However, it is unclear which aquatic species these efforts support under the water surface. This project will use molecular methods to identify a subset of species ranging from “microbes to zooplankton” indicative of wetland conditions in different stages of restoration. The project will also measure the food web resources the wetlands provide to larval fish. This information will help managers prioritize restoration efforts that are most likely to help declining aquatic species directly. *Funded by the Delta Stewardship Council and US Bureau of Reclamation	Michelle Jungbluth, San Francisco State University, Estuary and Ocean Science Center	Info Sheet

2018-2019 Awards

In 2019, the Delta Science Program, the California Department of Fish and Wildlife (CDFW), and the U.S. Bureau of Reclamation awarded $16.9 million for 26 high-priority science research projects in the Delta.

The Council’s Delta Science Program selected 15 projects listed below for $9.6 million in funding. These projects range in cost from about $200,000 to $1 million. Reclamation contributed almost $2 million toward four projects (denoted by *). CDFW awarded $7.3 million in Proposition 1 funding for 11 additional projects. More information about CDFW’s awarded projects can be found on CDFW’s website.

To learn more about these projects, we invite you to view the StoryMap created by 2022 California Sea Grant State Fellow Tabitha Birdwell. It takes readers on an immersive virtual tour across the Delta, summarizing key points of each project, including the catalyst behind the research, key research steps, and resulting management implications or public benefits. It connects research and management priorities for each project by highlighting contributions to the 2017-2021 Science Action Agenda’s five Action Areas.

Project Title	Description	Lead Principal Investigator
Next-generation multi-hazard levee risk assessment	In June 2004, a 350-foot levee failure near Stockton highlighted the vulnerability of Delta levees, flooding homes, and farmland while endangering the state’s water supply. With threats like sinking agricultural fields, rising sea levels, more severe floods, and earthquakes, addressing these risks could cost $3.8–$4.3 billion over the coming decades. This study combined 3-D modeling with detailed data on levee structures to analyze how they respond to these hazards. The research provides tools to guide more innovative investments and enhance protections across the Delta by developing improved methods for assessing levee risks and producing updated Delta-wide hazard data. *Funded by the Delta Stewardship Council	Scott Brandenberg, University of California, Los Angeles
An evaluation of sublethal and latent pyrethroid toxicity across a salinity gradient in two Bay-Delta fish species	Pyrethroids, a toxic insecticide commonly detected in the San Francisco Bay and Delta (SFBD), were investigated for their effects on fish populations, particularly Delta smelt and Inland silverside. While existing regulations focus on lethal concentrations, this study examined non-lethal impacts on fish embryos under the SFBD's unique salinity conditions and the presence of sediment. The findings revealed how pyrethroids affect fish during early life stages, providing critical insights to improve pesticide regulations and better protect fish populations in the Bay-Delta ecosystem. *Funded by the Delta Stewardship Council and US Bureau of Reclamation	Susanne Brander, Oregon State University
Impact of temperature and contaminants on Chinook salmon survival: A multi-stressor approach	The decline of native salmon species in California, such as Chinook salmon, has been linked to multiple stressors during their migration, including disease, predation, and environmental challenges like pollution and elevated water temperatures. This study investigated how exposure to a contaminant mixture of bifenthrin (a pesticide) and triclosan (an antibacterial chemical) affects salmon health under different temperature conditions. Results demonstrated that these contaminants alter salmon's swimming behavior and critical physiological functions, with elevated temperatures exacerbating these effects. These findings provide insight into how combined stressors impact salmon during migration and emphasize the need for strategies to address pollution and temperature-related challenges. *Funded by the Delta Stewardship Council	Joseph Dietrich, NOAA Fisheries
Resolving contradictions in foodweb support for native pelagic fishes	Research in the Delta has shown that low plankton productivity is linked to declines in fish species like the endangered Delta smelt, which relies on Pseudodiaptomus forbesi, a small crustacean that forms about half its diet. This study examined these copepods' feeding, growth, and reproduction across four habitats: two open-water channels and two shallow areas. Researchers measured copepods' feeding rates on microscopic plants and animals and used computer models to estimate their movement and mortality. The findings reveal how copepods use different nutritional sources to grow and reproduce, providing insights into how Delta food webs respond to large-scale changes such as habitat restoration and upgrades to the Sacramento wastewater treatment plant. *Funded by the Delta Stewardship Council	Win Kimmerer, San Francisco State University
Assessing sediment nutrient storage and release in the Delta: linking benthic nutrient cycling to restoration, aquatic vegetation, phytoplankton productivity, and harmful algal blooms	Nutrients in sediment significantly influence Delta food webs, harmful algal blooms, aquatic vegetation, and drinking water quality. This study examined nutrient amounts, types, and behavior in Delta sediments and the microbial communities that drive these processes. Researchers assessed how planned reductions in nutrient inputs following upgrades to the Sacramento Regional County Sanitation District’s wastewater treatment plant may impact sediment nutrients and microbes. The study also explored how these factors affect wetland restoration and invasive aquatic vegetation. The findings can improve computer models to guide large-scale nutrient management actions in the Delta. *Funded by the Delta Stewardship Council	Tamara Kraus, US Geological Survey
Evaluating juvenile salmonid behavioral responses to hydrodynamic conditions in the Sacramento-San Joaquin Delta	This study combined detailed model predictions with six years of salmonid tracking data to examine how river flows influence steelhead movement through the Delta. Researchers analyzed behavioral responses across several water years, evaluating steelhead behavior in relation to current regulatory flow requirements, such as Old and Middle River Flow and the Inflow-to-export ratio. They also assessed five new water management metrics proposed by the Collaborative Adaptive Management Team Salmonid Scoping Team. The findings improve understanding of the conditions that affect steelhead survival, supporting more effective water management strategies in the Delta. *Funded by the Delta Stewardship Council and US Bureau of Reclamation	Michael MacWilliams, Anchor QEA - State Water Contractors
Recreational hunting as an ecosystem service of restoration in the Bay-Delta watershed	Ecological restoration in the Delta watershed benefits native plants and animals while increasing hunting opportunities for recreational users, an often-overlooked economic dividend of habitat restoration. This study quantified the economic impact of restored sites that provide new or improved hunting access by surveying members of the public at locations in the Delta and Sacramento River regions. The analysis evaluated the dollar value of these opportunities and examined tradeoffs among recreational use, carbon storage, and habitat quality at restored sites. Additionally, the survey assessed whether users perceive an unmet need for recreational access in the region. These findings can help explain the multi-benefit nature of restoration projects to stakeholders and policymakers and provide critical insights for balancing ecological, economic, and recreational priorities in future restoration efforts. *Funded by the Delta Stewardship Council	Virginia Matzek, Santa Clara University
An improved genomics tool for characterizing life history diversity and promoting resilience in Central Valley Chinook salmon	The diversity of Chinook salmon migration timing had decreased in the Central Valley. A key roadblock to protecting this diversity was the inability to rapidly and inexpensively identify large numbers of individuals from different populations during their migration to the ocean. This study addressed this information gap by leveraging pre-existing genomic data to develop a new technique that allowed scientists to identify individuals by life history type and location. For example, it identified Fall Run Chinook from the Sacramento versus the San Joaquin River basins. This information and data on water temperature and river flows determined the relationship between environmental conditions and diversity in juvenile salmon life histories. The findings allow managers to accurately monitor the effects of key management actions on different Central Valley Chinook salmon populations. *Funded by the Delta Stewardship Council	Mariah Meek, Michigan State University
Improving green sturgeon population and migration monitoring	Green sturgeon, a species protected under the federal Endangered Species Act, was the focus of this project, which aimed to support the recovery and management of the southern distinct population segment by improving population and migration monitoring. Enhanced monitoring is recommended in initiatives like the Green Sturgeon Recovery Plan, but uncertainty remains to be made about the effectiveness of current techniques. To address this, researchers compared different monitoring and estimation methods, using sonar technology in the Sacramento River to estimate population size and by-catch mortality. They also reviewed past acoustic telemetry data to evaluate its potential for improving population estimates. *Funded by the US Bureau of Reclamation	Peter Dudley, University of California, Santa Cruz
Integrated science and management of nutrient, salt, and mercury export from San Joaquin River wetland tributaries to the Delta	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 provided improved best practices and guidelines for the management of salt, nutrients, and mercury in wetlands. Results addressed key knowledge gaps identified in the Delta Nutrient Research Plan and provide support for the Delta Mercury Control Plan. *Funded by the Delta Stewardship Council	Peggy O’Day, University of California, Merced
Tidal wetland restoration in the Bay-Delta Region: Developing tools to measure carbon sequestration, subsidence reversal, and climate resilience 2021	Tidal marshes in the Delta are vital ecosystems that remove carbon from the atmosphere, buffer communities from rising sea levels, reduce excessive nutrients, and provide habitat and food for diverse species. However, understanding how tidal marshes change naturally versus in response to climate change, restoration, and water quality is challenging. This project produced the first multi-year dataset of a tidal marsh’s complete carbon budget, enabling predictions of seasonal and annual carbon budgets across different salinities. Using remote sensing data, the project developed an open-source model to evaluate the sustainability of existing and restored tidal wetlands over the next 100 years. This tool supports wetland managers and decision-makers in restoring and managing Delta tidal wetlands in a changing climate. *Funded by the Delta Stewardship Council and US Bureau of Reclamation	Patty Oikawa, California State University, East Bay
Quantifying the contribution of tidal flow variation to survival of juvenile Chinook salmon	This project aimed to quantify how tidal patterns in the Delta influence the survival of juvenile salmon. Researchers observed that juvenile salmon survival improves when river flow is higher and tidal influence is lower, hypothesizing that reduced travel times limit predator exposure. To test this, the project employed multiple models, including tools to predict how management actions that alter tidal patterns might impact salmon survival. These findings can support efforts to improve conditions for juvenile salmon in the Delta. *Funded by the Delta Stewardship Council	Russel Perry, US Geological Survey
Changes in organic carbon and food resources in response to historical events in the Sacramento-San Joaquin Delta: A synthesis project	Recent management strategies in the Delta have focused on habitat restoration and water quality improvement to restore ecosystem function. Still, monitoring programs struggle to measure key processes like food web dynamics. This study investigated changes in the sources, quantity, and quality of organic carbon that fuel the Delta food web. Researchers collected data from fifteen sites representing dominant sub-habitats to identify available food resources and examined how these resources are influenced by wastewater treatment and habitat restoration. Insights into organic carbon from historical and current perspectives can help set realistic goals for ongoing and future Delta restoration efforts. *Funded by the Delta Stewardship Council	Christina Pondell, Virginia Institute of Marine Science
Synchrony of native fish movements: synthesis science toward adaptive water management in the Central Valley	Native California fish, including salmon, are declining and require enhanced conservation efforts. Acoustic telemetry technologies have become vital for tracking fish migration through the Central Valley, but the wealth of existing telemetry data hasn’t been thoroughly studied yet. This project synthesized 10 to 15 high-quality telemetry datasets covering various native fish species and life stages to uncover patterns and insights. Guided by a Technical Advisory Group of conservation experts, the study developed new frameworks to analyze these datasets, ensuring robust results and rapid communication to decision-makers. The findings can offer valuable guidance on water management practices to improve the survival of native fish populations. *Funded by the US Bureau of Reclamation	Andrew Rypel, University of California, Davis
Low-cost satellite remote sensing of the Sacramento-San Joaquin Delta to enhance mapping for invasive and native aquatic vegetation	Invasive aquatic plants have been taking over waterways in the Sacramento-San Joaquin Delta, doubling their range in the past 15 years. These plants harm native species by changing habitats and water quality, and controlling them cost California millions of dollars each year. To improve management, researchers studied how these plants grew and spread and what made them vulnerable. They used the Sentinel-2 satellite to monitor the plants from space year-round, filling gaps left by older surveys. The project tracked invasive and marsh plants and measured how often floodplains, like the Yolo Bypass, were flooded. The findings can provide new ways to measure success in restoring habitats and controlling invasive plants in the Delta. *Funded by the Delta Stewardship Council	Susan Ustin, University of California, Davis

Early 2000s

The 2004, 2006, 2007, and 2010 proposal solicitations resulted in combined funding of 48 proposals for a total of over $27 million. In 2010, 13 research projects were awarded through a proposal solicitation and resulted in more than 70 peer-reviewed papers and have informed how the Delta is managed. To learn more about these solicitations, email deltasciencesolicitation@deltacouncil.ca.gov.