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  • 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

    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

    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 June 3, 2024
  • Title

    Enhanced Delta Smelt Monitoring [EDSM]

    Lead U.S. Fish and Wildlife Service [USFWS]
    Description

    Description:
    The Enhanced Delta Smelt Monitoring (EDSM) program is a comprehensive, year-round monitoring initiative that employs multiple research crews conducting concurrent trawling operations across designated strata within the San Francisco Estuary. The program specifically targets post-larval Delta Smelt from April through June using 20mm trawling gear, while Kodiak trawling gear is utilized for the remainder of the year.
    Need:
    The ongoing decline of the Delta Smelt population has underscored the critical need for continuous improvement in the data supporting our understanding of the ecological and anthropogenic factors influencing Delta Smelt population dynamics. The EDSM program plays a vital role in providing essential biological data that informs management strategies aimed at mitigating the adverse effects of water operations on this endangered species. By capturing data across nearly all life stages of Delta Smelt, including near-real-time information on juvenile and adult stages, the EDSM program offers significant conservation benefits. This data is promptly disseminated to the Smelt Working Group and other resource managers to facilitate informed decision-making during the critical entrainment season.
    Objectives:
    -Estimate the total abundance of Delta Smelt, including standard errors or confidence intervals, on a weekly to bi-weekly basis across various life stages (post-larvae, juveniles, sub-adults, adults) throughout the year.
    -Assess the spatial distribution of Delta Smelt at a management-relevant temporal and spatial resolution.
    -Provide data that supports management decisions and addresses scientific inquiries related to sampling efficiency, drivers of Delta Smelt population patterns, and other conservation and management-related topics.
    Science topics Conductivity, Crustaceans, Delta Smelt, Dissolved oxygen, Endangered species, Fish, Invertebrates, Jellyfish, Main channels, Monitoring methods and techniques, Mysis, Other species, Pelagic fish, Salinity, Temperature, Turbidity, Water conveyance / infrastructure, Water management, Water operations / exports, Water temperature
    Updated May 23, 2025
  • Title

    Delta Juvenile Fish Monitoring Program [DJFMP]

    Lead U.S. Fish and Wildlife Service [USFWS]
    Description

    The Delta Juvenile Fish Monitoring Program (DJFMP) has monitored natural-origin and hatchery-origin juvenile Chinook Salmon (Oncorhynchus tshawytscha) and other fish species within the San Francisco Estuary (SFE) since 1976 using a combination of midwater trawls and beach seines. Since 2000, three trawl sites and at least 58 beach seine sites have been sampled weekly or biweekly within the SFE and lower Sacramento and San Joaquin Rivers. The main objectives of the DJFMP are:
    1. Document the long-term abundance and distribution of juvenile Chinook Salmon in the Delta.
    2. Comprehensively monitor throughout the year to document the presence of all races of juvenile Chinook Salmon.
    3. Intensively monitor juvenile Chinook salmon during the fall and winter months for use in managing water project operations (Delta Cross Channel gates and water export levels) on a real-time basis.
    4. Document the abundance and distribution of Steelhead.
    5. Document the abundance and distribution of non-salmonid species.

     
    Science topics Aquatic vegetation, Chinook Salmon, Conductivity, Crustaceans, Dissolved oxygen, Endangered species, Environmental drivers, Estuaries, Fish, Habitat, Historical ecology, Intertidal / transition zones, Invasive / non native species, Invertebrates, Jellyfish, Main channels, Monitoring methods and techniques, Mysis, Open water, Other species, Pelagic fish, Salinity, Salmon migration, Salmon rearing, SAV/FAV, Steelhead Trout, Turbidity, Water conveyance / infrastructure, Water management, Water operations / exports, Water temperature
    Updated May 21, 2025
  • Title

    Assessing sea-level rise and flooding changes in the Sacramento/San Joaquin Delta using historical water-level records

    Lead California State University [CSU]
    Description The project aims to recover, digitize, and analyze more than 1300 station years of ‘lost-and-forgotten’ water level records collected from 1857 to 1982 in the Sacramento-San Joaquin Delta. These measurements, augmented by modern data, will improve our understanding of tidal, flood, and sea level trends in the system. By determining ‘hotspots’ of habitat and flood risk sensitivity, the results may be used to better focus future scientific and management priorities, to protect the environment, manage flood risk, and enhance community resilience to climate change
    Science topics Backwater, Climate change, Environmental drivers, Estuaries, Land elevation, Levees, Outflow, Sea level rise, Stage, Subsidence, Surface water / flow, Tides, Velocity, Vessels and shipping channels, Water, Wind
    Updated October 10, 2023
  • Title

    Open-Source Resources for the Sacramento-San Joaquin Delta Telemetry Research Community

    Lead Cramer Fish Sciences
    Description There is a great deal of telemetry data amassed from studies in the Sacramento-San Joaquin Delta. It continues to grow every year with special studies and monitoring efforts. Multiple research priorities surrounding fish ecology in the Delta could be addressed, at least in part, by synthesizing the myriad telemetry data sets that exist; this work would benefit greatly from the centralization and standardization of data workflows surrounding telemetry research. With the guidance of a PIT Advisory Team, we plan to establish a collection of open-source, technology-agnostic, accessible resources to support a reproducible and transparent telemetry data workflow for researchers in the region. The workflow and resources do not invent new procedures, rather improve and standardize those already used by the telemetry research community. This will bring us in closer alignment with centralized, coordinated data workflows that have been successfully implemented in other regions and data communities. The final open-source set of resources will include a design and roadmap for implementing a central telemetry database and workflow, an R package for the preparation, QA/QC, and basic analysis of telemetry data, and a regional workshop offering training programs in the proposed telemetry data workflow.
    Science topics Chinook Salmon, Fish, Other species, Salmon migration, Steelhead Trout, Striped bass, Sturgeon
    Updated August 26, 2024
  • Title

    Standard Operating Procedure for Diagnosing and Addressing Predator Detections in Salmon Telemetry Data

    Lead University of Washington [UW]
    Description Tag predation is a complicating factor in juvenile salmon telemetry studies that can bias results, delay timely reporting, and prevent effective data synthesis. This project addresses the problem by (1) characterizing predatory fish movement patterns from existing telemetry data in the Delta; (2) developing a standard operating procedure for diagnosing and handling detections of predated tags in salmon telemetry studies; and (3) implementing the recommendations in a software package in Program R that includes code, a “library” of expected predator behaviors, and example vignettes. The R package will be freely available for download at www.cbr.washington.edu.
    Science topics Chinook Salmon, Endangered species, Fish, Intertidal / transition zones, Invasive / non native species, Predation, Salmon migration, Steelhead Trout, Striped bass
    Updated April 30, 2025
  • Title

    Impacts of predation and habitat on Central Valley Chinook smolt survival

    Lead University of Vermont, USGS Vermont Cooperative Fish and Wildlife Research Unit
    Description The Sacramento River in California’s Central Valley has been highly modified over the past 150 years due to mining, urbanization, and impoundment/diversion of river flow to provide water for municipal, industrial, and agricultural needs. Land use changes combined with high levels of harvest have been accompanied by drastic declines in native salmon populations, including the once abundant Chinook salmon (Oncorhynchus tshawytscha). Further, the region has been subject to the introduction and widespread establishment of non-native fish species, some of which are predators of juvenile salmon. Of the four historic ecotypes of Chinook salmon (fall, late-fall, winter, and spring runs), winter- and spring-runs have been most impacted and are currently listed as endangered and threatened respectively under the US Endangered Species act. Past research has illustrated how smoltification of juvenile salmon and outmigration from freshwater to the ocean is a time of increased mortality, and reduced survival at this life stage can impact the number of reproducing adults returning to the system in subsequent years. While these studies have provided valuable information on how habitat and environmental conditions experienced by migrating Chinook salmon smolts can affect survival, they have primarily focused on individual ecotypes during the portion of the year where downstream migrations occur. However, variation in smolt size and migration timing among ecotypes can expose migrating fish to differing environmental conditions and levels of exposure to predation, which can present distinct risks for outmigration survival. To identify the areas and environmental conditions which have the greatest relative impact on juvenile survival for each ecotype, this project will use over ten years of data (2012-2022) from acoustically tagged smolts representing all four Chinook salmon ecotypes in the Sacramento River/Central Valley. Combining these data will increase sample size relative to previous studies, the range of environmental conditions (e.g., temperature, flow, and predator abundance) modeled, the range of fish sizes, and thus, the statistical power of our analyses. We hypothesize that each ecotype will have different factors that will be the primary drivers of mortality experienced during outmigration. To test our hypotheses, we will implement Cormack-Jolly-Seber (CJS) mark-recapture models to estimate both the probability of survival through reaches of the Sacramento River delineated by acoustic receivers, and the detection probability in each reach. Survival will be modeled as a function of individual, release group, reach-specific, and time-varying covariates. Further, to examine the relative impact of predation on smolt survival, we will include an additional covariate representing predator-prey encounter rates using the Mean Free-path Length model. Finally, model selection will be applied to a series of CJS models to assess the relative impact of each covariate on smolt survival for each of the four Chinook ecotypes.
    Science topics Chinook Salmon, Environmental drivers, Fish, Flows, Habitat, Predation, Salmon migration, Water temperature
    Updated February 2, 2024
  • Title

    White Sturgeon Telemetry Synthesis

    Lead Cramer Fish Sciences
    Description Acoustic telemetry studies are expensive and logistically demanding. A new study to tag and monitor 315 White Sturgeon would require a massive field effort by a large team, but by pooling and leveraging existing datasets, this sample size and analysis will be achieved at a fraction of the cost and effort. In recognition of the efficiencies gained by this approach, the Delta Stewardship Council’s Science Program lists the synthesis and analysis of existing telemetry datasets in Science Action Area (SAA) 2. This project directly addresses SAA 2 by capitalizing on existing White Sturgeon telemetry data through the synthesis of three existing large telemetry dataset to understand system-wide White Sturgeon movements. This contract will synthesize existing long-term acoustic telemetry datasets in order to address high priority research questions for the management of White Sturgeon in the San Francisco Estuary system. These questions include: 1. What is the periodicity of spawning migrations by tagged White Sturgeon, and how do these estimates compare to those from previous, single-basin studies? 2. What is the scope and variability of inter-basin movements exhibited by tagged adult White Sturgeon across years? 3. Is there individual fidelity to specific migration routes or sites within each river basin? 4. Do White Sturgeon migrating through the Yolo Bypass experience delays in reaching spawning grounds relative to fish using the mainstem Sacramento River or San Joaquin River routes? 5. Is the onset of upstream migration movement by individuals associated with a characteristic flow rate or event? This contract will serve as a model for future telemetry synthesis studies by adhering to best practices in scientific computing for reproducible, transparent research, and by making all parts of the data and analysis accessible to the broader Delta research community.
    Science topics Environmental drivers, Fish, Flows, White Sturgeon
    Updated May 21, 2024
  • Title

    Suisun Landscapes: historical ecology, functional metrics, and community priorities for landscape planning

    Lead San Francisco Estuary Institute [SFEI]
    Description

    To support management planning in Suisun Marsh, this project is developing a body of science and tools to understand past, present, and potential future changes to the Marsh’s ecological patterns, processes, and functions. This project builds on SFEI’s prior work in the Delta, extending historical ecology mapping, landscape change studies, and the Landscape Scenario Planning Tool to cover Suisun's historical and present-day landscapes. Through spatially explicit representations of the historical function and condition of the marsh and analyses of landscape metrics, this project is evaluating changes over time in landscape support for ecosystem functions and services in Suisun. In order to incorporate diverse perspectives into planning resources, project activities include engagement with local tribes and community members to understand community interests, priorities, and uses of the Marsh. Findings will be shared through a report and article for both technical and general audiences, and spatial analyses and data layers will be made available through the Landscape Scenario Planning Tool.

     
    Science topics None specified
    Updated October 10, 2024