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  • 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, Green sturgeon, Habitat restoration, Salmon migration, Salmon rearing, Steelhead Trout, Sturgeon, White Sturgeon
    Updated July 22, 2024
  • 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

    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

    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

    Fish Diet and Condition

    Lead California Department of Fish and Wildlife [CDFW]
    Description Description The Diet and Condition study has provided information on the food habits of pelagic fishes in the estuary since 2005. We focus on the temporal and spatial differences in diet composition and feeding success of Delta Smelt, Striped Bass, Threadfin Shad, Longfin Smelt, Mississippi Silversides, and American Shad. Need Data from this project has been used to inform the Fall Low Salinity Habitat Program (FLaSH), Directed Outflow Project (DOP), and Management, Analysis and Synthesis Team reports, as well as life history models used for the conservation of fish and their habitats. Understanding what prey are utilized for food in the context of available prey, with the associated body-condition of fish, helps clarify the existence and timing of food limitation for young pelagic fish in the estuary. This work began as part of the Pelagic Organism Decline investigations and continued as a contributor to FLaSH investigations during which we in collaborated with the Fish Health Monitoring Project. Recently staff completed Longfin Smelt diet investigations as part element #296 (Longfin Smelt Investigations – in response to a litigation agreement) that will also contribute to the Longfin Smelt Conceptual Model and Synthesis effort (element #320). Finally, we will process Delta Smelt diets from investigations prompted by the Delta Smelt Resilience Strategy, and as part of the DOP. Objectives 1. What are the diets of pelagic fishes (especially Delta Smelt and Longfin Smelt) in the estuary and do they vary regionally or temporally? 2. Is there evidence of reduced feeding success spatially or temporally in the estuary? 3. Is feeding success associated with changes in relative weight or condition of fish? 4. Is there seasonal and regional overlap of diets between species (with a focus on age-0 Delta Smelt, Longfin Smelt, Striped Bass, Prickly Sculpin, Pacific Herring, and Threadfin Shad)?
    Science topics None specified
    Updated April 29, 2022
  • Title

    Aquatic Habitat Sampling Platform: Standardized Fish Community Sampling Across Habitat Types

    Lead U.S. Bureau of Reclamation [USBR]
    Description Description The Aquatic Habitat Sampling Platform (AHSP) is an integrated aquatic species and habitat sampling system that can effectively monitor aquatic organisms and reveal habitat associations while having minimal or no “take” of sensitive species. Further development and deployment of the AHSP will expand data collection to shallow and off-channel habitat, while offering the capability to transition to deeper and open water habitats, providing reliable sampling efficiency estimates (e.g., probability fish detection) and “catch” per unit effort (i.e., number of individual species per volume of water sampled) and improving our knowledge about populations, habitat associations and major stressors of key organisms within the San Francisco Estuary (Estuary). Need Within the Estuary, numerous monitoring techniques are used. However, monitoring weaknesses for determining fish status and trends include: 1) restricted locations available for some techniques;2) limited ability to simultaneously assess zooplankton and fish larvae;and 3) difficulty in estimating fish population size due to lack of gear efficiency information (Honey et al. 2004). Furthermore, past attempts at integrated abundance indices from more than one sampling method have had limited success. Although there continues to be considerable collaborative monitoring and research devoted to understanding Central Valley fish species, coordination among activities has been difficult. Other issues include permitting take of listed species and time-consuming monitoring with extended periods of down time due to sample post-processing of fish and invertebrate species. Identification of key microhabitats for each lifestage and attributes and linking associated physical parameters such as habitat features (e.g., depth, structure, channel type) and water quality is needed. Objectives • Test AHSP operation within the Estuary while providing information highly relevant to pressing Delta management issues (IEP 2016); • Provide detailed information on distribution and approximate abundance of adult Delta Smelt within identified habitat types (Biological Opinion on the Long-Term Operational Criteria and Plan for coordination of the Central Valley Project and State Water Project;https://www.fws.gov/sfbaydelta/documents/SWPCVP_OPs_BO_12-15_final_OCR.pdf);and • Assess habitat associations and diurnal behavior of Delta Smelt and other fishes (Durand 2015).
    Science topics Delta Smelt
    Updated April 29, 2022
  • Title

    Central Valley Salmonid Coordinated Genetic Monitoring [Year 4]

    Lead U.S. Bureau of Reclamation [USBR]
    Description Description This work will include tasks to rapidly identify winter-run Chinook juvenile salmon at the CVP/SWP salvage facilities, process juvenile salmonid tissues from various CVPIA and IEP fish monitoring stations, and support coordination of genetic monitoring across the CVP and SJRRP programs. PIs: Josh Israel (USBR);Scott Blankenship (Cramer Fish Science);Ken Bannister (USFWS);John Carlos Garza (NOAA-Fisheries);Brett Harvey (DWR);Noble Hendrix (QEDA);Rachel Johnson (NOAA-Fisheries);Mariah Meek (UC Davis);Kevin Reece (DWR) Need This study is needed due to the limited accuracy of Lenght at Date stock identification. Inaccurate identification of Chinook salmon is problematic because it compromises the management value of data collected from standard monitoring programs. This project will improve the science and management value of the Central Valley salmon monitoring network, supported through IEP and Central Valley Project Improvement Act (CVPIA) monitoring stations, by accurately determining stock identification of multiple Chinook salmon stocks across their distribution. Classification tables will be developed to characterize monthly and seasonal accuracy between length-at-date and genetic race assignment at IEP and BiOp monitoring locations. This multi-year dataset will be used to evaluate the likelihood of accurate assignment and potential biophysical explanatory variables influencing genetic accuracy. Objectives Improve accuracy of CVPIA and IEP monitoring programs by providing genetic stock identification information for tissues collected from Red Bluff, Knights Landing, DJFMP, salvage facilities and San Joaquin River fish monitoring stations. Samples will be collected from all four runs of Chinook salmon based on length-at-date (i.e., samples will be collected from Chinook of various sizes throughout the sampling period).
    Science topics Chinook Salmon
    Updated April 29, 2022
  • Title

    Enhanced Acoustic Tagging, Analysis, and Real-Time Monitoring

    Lead National Oceanic and Atmospheric Administration [NOAA]
    Description Description This project tracks the movement and survival of wild and hatchery juvenile Chinook salmon with a large acoustic receiver network (JSATS), including real-time receivers, and the development of real-time metrics and retrospective modeling of juvenile salmon migration data. Need There is a well-documented need for improved detection and associated modeling of salmon migration and survival in the Central Valley. Understanding salmon survival and movement dynamics in the Delta and its tributaries is critical to the operation of state and federal water projects, recovery of ESA-listed species, and sport and commercial fisheries management. Objectives • Maintain 20 real-time JSATS receivers: will provide information on migrating salmon smolt location and timing of Delta entry and exist, which is key for informing time-sensitive decisions • Deployment of autonomous JSATS receiver array: this will provide fine-scale reach-specific survival and movement rates • Development of new metrics for the real-time data: this will inform key management relevant questions, such how many fish are entrained at critical junctions • Development of real-time website to convey movement and survival rates of acoustic tagged juvenile salmonids at various real-time locations in the Sacramento River and Delta.
    Science topics Salmon migration
    Updated April 29, 2022
  • Title

    Directed Field Collections

    Lead California Department of Fish and Wildlife [CDFW]
    Description Description The Direct Field Collections element (-089) provides funding support for expanded field collections, allowing CDFW to provide other, IEP-approved researchers access to research-capable boats and experienced operators, and thus the ability to safely sample the upper San Francisco Estuary. This element most recently facilitated investigations associated with the Fall Low Salinity Habitat (FLaSH) project and the Directed Outflow Project (DOP). Need This element allows CDFW and thus IEP to provide boat and operator time to assist collaborating researchers leading approved IEP projects with “on-the-water” sampling. There is no mandate for this element. Objectives To provide CDFW operational flexibility to assist collaborating researchers leading approved IEP projects with access to CDFW boat operators and boats to complete "onthe-water" sampling.
    Science topics None specified
    Updated April 29, 2022
  • Title

    Estimating Abundance of Juvenile Winter-run Chinook Salmon Entering and Exiting the Delta [SAIL]

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

    This is a continuation of a five-year project funded by CDWR and CDFW and the Central Valley Project Improvement Act in 2017. The objective of the project is to improve estimates of population abundances for fall, winter and spring run juvenile Chinook Salmon at Sacramento and Chipps Island by improving trawl efficiency estimates using data from releases of coded wire tags (CWT), acoustic tags (AT), and by genetically sampling the trawl catch in 2025 and 2026. The project will (1) develop statistical models for estimating trawl efficiencies using 2016-2025 data for paired AT-CWT releases of winter run and fall-run Chinook Salmon; (2) use 2016-2025 genetic sampling of trawl catch in combination with efficiency estimates to estimate population abundances of fall, spring and winter run at Sacramento and Chipps Island for 2016-2025; (3) implement trawl efficiency studies for multiple salmon runs in 2025-2026 informed by the prior results and in coordination with hatcheries for inclusion of AT fish with existing CWT releases; and (4) combine trawl efficiencies with genetic samples of trawl catch to provide estimates of fall, spring and winter-run salmon abundance (with estimated precision) entering and exiting the Delta in 2016-2025.
    Science topics Chinook Salmon
    Updated May 14, 2025
  • 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. Additionally, the program incorporates gear efficiency experiments and shallow water sampling protocols whenever feasible to enhance data collection.
    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 Delta Smelt
    Updated May 8, 2025
  • Title

    Effect of Outflow Alteration upon Delta Smelt Habitat, Condition and Survival

    Lead U.S. Bureau of Reclamation [USBR]
    Description Description The Directed Outflow Project (DOP) is a continuing collaborative effort among a dozen state, federal and non-governmental groups. The DOP will employ a focused spatial and temporal approach to evaluate mechanistic hypotheses directly related to the rationales provided for the summer Delta outflow action and Yolo Bypass Toe Drain action to benefit Delta Smelt, with direct relevance to the fall outflow action. Paired data collections (same location and time) of abiotic and biotic habitat constituents to test specific hypotheses will assist in avoiding prior shortcomings of using data collected for different studies/hypotheses and/or across variable spatial/temporal scales (as discussed in MAST [2015] and elsewhere). Sampling will occur during the Delta Smelt juvenile rearing-stage, a period known to be associated with the location of the low salinity zone (LSZ). Results should strengthen our understanding of the mechanisms and drivers impacting Delta Smelt vital rates and associated habitat features with a focus on outflow conditions. Results should assist in evaluating the benefit and feasibility of future flow augmentation actions for managers and decision makers. Results from this and other related studies will inform evaluations on which particular outflow-related action or group of actions provides the most benefit for Delta Smelt. Need Requests and plans for water management actions related to augmentation of Delta outflow have proceeded and are expected to proceed in the future. However, there is uncertainty and disagreement regarding the mechanistic relationship of Delta outflow during the rearing period to Delta Smelt vital rates and habitat, and the hypothesized benefit of outflow alteration for Delta Smelt. Delta outflow has experienced reductions in recent years, coinciding with the collapse of the Delta Smelt. Reduced outflow has been linked to reductions in habitat suitability in Suisun Bay and Marsh and movement of the LSZ to the Confluence of the Sacramento-San Joaquin River where little connection to shallow open water habitats exists. Objectives The DOP’s main objective will be to evaluate the hypothesized benefit of outflow alteration for Delta Smelt and its habitat in coordination with all stakeholder groups. The following process and product related sub-objectives will facilitate progression toward this evaluation objective. • Test mechanistic hypotheses addressing the rationale behind outflow-based actions to benefit Delta Smelt. • Concurrently sample fish and measure abiotic/biotic habitat conditions at each randomly selected location along the salinity and habitat gradient of the north to western Delta along the Sacramento River during the summer and fall.
    Science topics Delta Smelt
    Updated April 29, 2022
  • Title

    Integrating Measurement of Fish Body Condition within the Delta Juvenile Fish Monitoring Program [DJFMP]

    Lead U.S. Fish and Wildlife Service [USFWS]
    Description Description The aim of this pilot effort is to begin assessing methods and developing protocols for incorporating measurement of fish body condition (Fulton’s Condition Index, K) into standard Delta Juvenile Fish Monitoring Program (DJFMP) sampling. Need The goal of this study is to examine the utility of fish body condition as a measure for DJFMP to evaluate underlying factors driving fish health and survival in the Sacramento and San Joaquin River-Delta system. This will provide a more complete assessment of how condition metrics vary for common fish species that are sensitive to differences in environmental conditions, filling a fundamental data gap in our existing monitoring program. Objectives • Establish a pilot sampling design and methods for collection of data from fish sampled through DJFMP. • Assess the utility and expand the use of body condition to include up to 7 species of commonly sampled fishes. • Develop protocols for incorporating new methods into DJFMP sampling.
    Science topics Fish
    Updated April 29, 2022
  • Title

    Sacramento Prediction and Assessment of Salmon [SacPAS]

    Lead U.S. Bureau of Reclamation [USBR]
    Description CVPAS for Central Valley Prediction and Assessment of Salmon, extends and improves the SacPAS real-time web database and fish forecasting tools to other river systems in the Central Valley. The goal is to integrate environmental/fish data, fish passage/survival models and output from water quality models into a web-accessible analysis and visualization system. The website provides support for regional integration and public access to Reclamation and ESA-mandated activities.
    Science topics None specified
    Updated November 18, 2022
  • Title

    SAIL [Coordinated Enhanced Acoustic Telemetry Program]

    Lead U.S. Bureau of Reclamation [USBR]
    Description These monitoring efforts can provide critical information on juvenile salmonid distribution and survival, which inform biologists and managers interpretations of the exposure and intensity of CVP and SWP water operation risks on tagged populations in Central Valley rivers and the Bay- Delta. Understanding salmon survival and migration dynamics in the Delta and its tributaries is critical to the recovery of ESA-listed species, and sport and commercial fisheries management. For example, estimating the population size of endangered Sacramento River Winter-run Chinook (SRWRC) as they enter and exit the Delta is considered critical for informing Delta water management actions (Interagency Ecological Program (IEP) SAG 2013). “The use of realtime acoustic receivers that immediately transmit acoustic tagged (AT) fish detections needs to be included in the expanded network” (Johnson et al., in press). Tracking the fate of individual tagged fish will be accomplished with AT and used to develop estimates of survival and movement for other non-AT fish also part of that group. Population level sampling programs will use survival estimates generated by AT and applied to other mass marked (coded wire tagging) groups to develop improved capture efficiency for these sampling programs. Objectives: • Deploy and service field monitoring acoustic telemetry stations at locations important to fish and water management. • Implant, transport, and release acoustically tagged juvenile ESA-listed wild and hatchery juvenile salmonids. • Analysis and synthesis to support production and development of new metrics for understanding the survival, distribution, and entrainment of juvenile salmonid along the Sacramento River and its floodways, as well as, the Bay-Delta. Six-Year Steelhead Study Continuation Reclamation’s Proposed Action for ROC on LTO Section 4.10.5.12.3 Additional Measures includes a San Joaquin Basin Steelhead Telemetry Study -- Continuation of the 6-Year Steelhead telemetry study for the migration and survival of San Joaquin Origin Central Valley Steelhead. This investigation involves undertaking experiments utilizing acoustically-tagged salmonids to confirm proportional causes of mortality due to flows, exports, and other project and non-project adverse effects on steelhead smelt out-migrating from the San Joaquin Basin and through the southern Delta. This study is to coincide with different periods of operations and focus on clipped hatchery steelhead (Oncorhynchus mykiss). The period of interest is between February 15 and June 15, which coincides with a majority of O. mykiss outmigration from the Stanislaus River and recoveries of steelhead smolts in the Mossdale fish monitoring efforts. This period is to include changes in CVP/SWP operations that include reductions in exports, reductions in reverse flows in Old and Middle rivers (OMR), and San Joaquin River pulse flows to assess the influence of flow and exports on juvenile steelhead survival. This study is designed to evaluate juvenile steelhead route selection at channel divergences in the south Delta and along the mainstem San Joaquin River, and how these behaviors influence survival in specific reaches and through the Delta to Chipps Island.
    Science topics None specified
    Updated April 29, 2022
  • Title

    Food Temperature Optimization Model for CVP

    Lead U.S. Bureau of Reclamation [USBR]
    Description This study aims to improve understanding of how nutrient and zooplankton exports from CVP reservoirs impact downstream food web productivity.
    Science topics None specified
    Updated April 29, 2022
  • Title

    Pacific States Marine Fisheries Commission Coleman-Nimbus Tagging

    Lead U.S. Bureau of Reclamation [USBR]
    Description 25% of fall- run Chinook tagged and clipped and annual report on hathchery contributions to fisheries and watersheds
    Science topics None specified
    Updated April 29, 2022
  • Title

    Red Bluff Diversion Dam Rotary Screw Traps

    Lead U.S. Bureau of Reclamation [USBR]
    Description Annual juvenile production estimates for ESA species in Sacramento River, Clear Creek, and Battle Creek
    Science topics None specified
    Updated April 29, 2022
  • Title

    Sacramento River Basin Salmonid Monitoring with Pacific States

    Lead U.S. Bureau of Reclamation [USBR]
    Description This study aims to monitor effectiveness of salmonid habitat improvement projects in the Sacramento River basin. Annual Chinook escapement estimates in Sacramento River and upper river tributaries and American, and habitat project juvenile monitoring.
    Science topics Chinook Salmon
    Updated April 29, 2022
  • Title

    Directed Outflow Project [DOP] - Paired Habitat Sampling

    Lead U.S. Bureau of Reclamation [USBR]
    Description Special study supporting water quality, food web, and biological measures regarding seasonal outflow and Delta Smelt.
    Science topics Flows, Water management
    Updated April 29, 2022
  • Title

    FCCL Conservation Hatchery Operation for Delta Smelt Refuge Population Maintenance and Research Support

    Lead U.S. Bureau of Reclamation [USBR]
    Description This facility houses the Delta Smelt Refuge population and produces Delta Smelt for release into the Delta. It is also responsible for the genetic management of the captive population and support of studies on supplementation.
    Science topics Delta Smelt
    Updated April 29, 2022
  • Title

    Continuous Flow and Water Quality Monitoring Network in the Sacramento-San Joaquin Delta

    Lead U.S. Geological Survey [USGS]
    Description This project envisions the continuation, expansion, and further integration of high frequency monitoring for flow, water quality (including chlorophyll and nutrients), sediment, as well as biological responses at key locations in the Delta and Suisun Bay. The physical properties monitored by the fixed-station network are the primary drivers of the habitat conditions and biological responses that management actions hope to achieve. Nutrient dynamics are explicitly measured at select stations to improve our understanding of how physical dynamics, water quality and landscape features shape the base of Delta food webs. These data will provide information about drivers linked to food quantity and quality as well as potential toxins production by harmful algae. Suspended-sediment monitoring provides an understanding of the inputs and internal exchanges between regions, locations of sources and sinks, and provides insight into the underlying cause of turbidity variability in the study area. Suspended-sediment measurements gage the availability of suspended sediment for existing marshes and for proposed large-scale marsh restoration efforts in the Delta. There are a total of 5 sub-tasks in this project: • Task 1: Hydrodynamics Team – Fixed Station Network Operation and Maintenance • Task 2: BioGeoChemistry Team -- Fixed Station Network Operation and Maintenance • Task 3: Delta Sediment Team – Fixed Station Network Operation and Maintenance • Task 4: Bay Sediment Team – Fixed Station Network Operation and Maintenance • Task 5: Project Management
    Science topics Chlorophyll A / B, Conductivity, Dissolved oxygen, Flows, Nutrients, pH, Phytoplankton, Sediments, Stage, Surface water / flow, Tides, Turbidity, Velocity, Water operations / exports, Water temperature
    Updated October 21, 2024
  • Title

    The effects of climate change on the life history of spring-run Chinook Salmon through time

    Lead University of California - Santa Cruz [UCSC]
    Description

    Chinook Salmon (Oncorhynchus tshawytscha) populations in California are in decline due to the combined effects of habitat degradation, water diversions, and shifting climate regimes. This project uses archival tissues (otoliths, vertebrae) from modern and ancient spring-run Chinook Salmon to understand how shifts in migration timing and habitat use allowed salmon to cope with highly variable environmental conditions. We will learn how salmon responded to the recent drought and flood periods (2012-2020 CE), the California Gold Rush Period (~1835-1870 CE), the Little Ice Age (~1560-1780 CE), and the Megadrought Period (~1200-1410 CE). This effort will provide the insights needed for developing climate-adapted conservation actions to support salmon into the future.
    Science topics Chemistry, Chinook Salmon, Climate change, Environmental drivers, Fish, Habitat, Salmon rearing
    Updated April 8, 2025