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Title	Operation Baseline Project 2C: Zooplankton, Romberg Tiburon Center, SFSU
Lead	San Francisco State University [SFSU]
Description	This project will examine responses of zooplankton (copepods) to variations in the foodweb attributable to nutrient sources. At each wetland site we will determine spatial abundance patterns and rates of reproduction, growth, and mortality. These will be integrated with information on phytoplankton and physical dynamics to determine how population dynamics responds to nutrient conditions. Stable isotopes will be used to assess nutrient source contributions to growth.
Science topics	Algae, Floating aquatic vegetation, Food webs, Nitrogen / ammonia, Open water, Other discharge contaminants, Phytoplankton, Submerged aquatic vegetation, Wastewater discharge, Water operations / exports, Wetlands, Zooplankton
Updated	December 14, 2022

Title	Mechanisms underlying the flow relationship of longfin smelt: I. Movement and feeding
Lead	San Francisco State University [SFSU]
Description	The project is to apply modern analytical methods, bioacoustic detection and particle tracking models to refine understanding of the vertical and longitudinal distribution of longfin smelt (Spirinchus thaleichthys) and how they are affected by flow and food availability. Funding will be used to conduct the research to protect and maintain the estuary's threatened longfin smelt population.
Science topics	Longfin Smelt
Updated	November 17, 2022

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

Title	Comparison of Nutrient Sources and Phytoplankton Growth and Species Composition in Two Rivers: Their Roles in Determining Productivity and Food Web Conditions in Suisun Bay and the Delta
Lead	San Francisco State University [SFSU]
Description
Science topics	Phytoplankton, Pelagic fish, Nitrogen / ammonia
Updated	April 29, 2022

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

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

Title	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	The Role of Microcystis Blooms in the Delta Foodweb: A Functional Approach
Lead	San Francisco State University [SFSU]
Description	We propose a collaborative investigation of blooms of the toxic, cyanobacteria Microcystis in the San Francisco Estuary Delta including how blooms develop, identification of toxic species and strains, controls on toxin production, and foodweb effects. The research will address Delta Science Program Priority Research Topic 2 and Research Topic 5 in the CALFED-funded analysis of ammonium issues in the Estuary. The appearance of Microcystis in the Delta was coincident with the POD, suggesting a link. The spatial and temporal scales of Microcystis blooms was identified with their environmental covariates but a mechanistic analysis of the conditions that distinguish bloom periods and locations, which are critical for ecosystem modeling and management, are still lacking. Our objectives are to determine: 1- the biotic and abiotic factors controlling Microcystis bloom formation and toxin production;2- how Microcystis strains and microbial associations influence toxicity;3- the role of Microcystis in the Delta pelagic food web and its effect on the POD through zooplankton grazing. Our 3-year work plan comprises 2 years of laboratory and field work (contrasting bloom and non bloom locations). Experiments will be conducted to determine mechanisms driving observed in situ patterns. We will synthesize the results and clarify the environmental-bloom-food web effects in a useable format for management efforts aimed towards water supply, fisheries and recreational use of the Delta.
Science topics	Harmful algal blooms HAB
Updated	April 29, 2022

Title	Modeling the Delta Smelt Population of the San Francisco Estuary
Lead	San Francisco State University [SFSU]
Description	The purpose of this project is to develop an individual-based particle-tracking model examining population behavior of Delta smelt under different scenarios.
Science topics	Delta Smelt
Updated	April 29, 2022

Title	Revealing the invisible contributors to the diets of larval longfin smelt and striped bass in the San Francisco Estuary.
Lead	San Francisco State University [SFSU]
Description	To better understand why the longfn smelt is threatened, the project compared the diet of larval longfn smelt to a thriving fsh with overlapping natal habitat and of similar size and morphology— the Pacifc herring. Using new genetic analysis methods, the project aimed to elucidate species composition of fsh diets in greater detail than has been done before and to measure diferences in composition and frequency of prey across habitats. In particular, the project aimed to identify prey items that were not previously seen using traditional diet analysis methods and assess whether any prey are indicative of natal habitats
Science topics	Fish, Longfin Smelt
Updated	February 26, 2024

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