Aquatic Ecosystems
Aquatic Ecosystems
Aquatic ecosystems information and data is neccessary for many California water management decisions including preservation of California's natural resources. The California Water Science Center conducts interdisciplinary research from aquatic species behavioral, population and community ecology, to the effects hydrologic extremes and climage change on ecosystems.
Filter Total Items: 81
Development of a spatially explicit ecosystem model to explore physiochemical drivers of step changes in POD species abundance and distribution in the Sacramento-San Joaquin Delta and Suisun Bay
Prior to 2000, the four most abundant resident pelagic fishes in the study area included two native species, delta smelt (Hypomesus transpacificus) a federal listed endangered species, and longfin smelt (Spirinchus thaleicthys) a state listed endangered species, and two introduced species, threadfin shad (Dorosoma petenense) and age-0 striped bass (Morone saxatilis).
Evaluation of Exposure and Vulnerability of Selected Inland National Wildlife Refuges in the Pacific Southwest to Water Resources Constraints in the Face of Climate Change using Downscaled Climate Change Modeling
As competition for water is growing, a major challenge is to ensure that sufficient quantities of good quality water are available for fish, wildlife, and plants. Competition for a limited supply of water with adequate water quality to support National Wildlife Refuges are a dominant threat for many National Wildlife Refuges across the U.S. and is only heightened during times of drought and in the...
Mapping Sturgeon Spawning Habitat in the Lower San Joaquin River
The spawning of adult white sturgeon ( Acipenser transmontanus ) in the lower San Joaquin River was documented recently by the United States Fish and Wildlife Service (USFWS) (Gruber and others, 2012; Jackson and Eenennaam, 2013). Streamflow on the San Joaquin River has been modified by State and Federal water project operations, and there are a variety of questions regarding the effects on fish...
Imaging 3D mammal burrow structure at 2 infested levee site with Ground-Based Tripod LiDAR
In advance of the US Army Corps of Engineers new policy enforcement that prohibits trees within 15-feet (4.5 meter) of levees and floodwalls, DWR, SAFCA, the US Army Corps of Engineers, University of California Berkeley, the University of California Davis, and USGS are studying the biological process (trees and mammal burrows) that have the greatest impact on levee integrity.
Pesticide Studies in the Sacramento/San Joaquin Delta and San Francisco Bay Estuary
The objectives of this specific study are to characterize the mixtures of current-use pesticides and pesticide degradates entering the Sacramento/San Joaquin Delta from its two main river sources over a period of 12 consecutive months.
Understanding Juvenile Salmon Entrainment and Survival in the South Sacramento/San Joaquin Delta Through the Use of Acoustic Telemetry and Hydrodynamic Measurements
This study will use the release-recapture information derived from the 2012 receiver array to populate a mark-recapture model based on a Cormack-Jolly-Seber model in combination with a route-specific survival model of Skalski et al. (2002) to derive maximum likelihood estimates and standard errors of reach specific survival and entrainment rates at important junctions, similar to what was used in...
Modeling in support of development of biocriteria for wadeable California streams and rivers
The State Water Resources Control Board (SWRCB) of California has initiated a process to develop biological objectives for wadeable freshwater streams and rivers for the entire state.
Suspended-Solids Concentrations in San Francisco Bay, California
Suspended solids are an important component of San Francisco Bay, California (USA) because they transport adsorbed toxic substances, provide habitat for benthic organisms, limit light availability and photosynthesis, and deposit in ports and waterways which require dredging. The U.S. Geological Survey has established a network of eight sites in San Francisco Bay at which suspended-solids...
San Francisco Bay Wetlands Priority Ecosystem Studies
The U.S. Fish & Wildlife Service's (USFWS) San Francisco Bay National Wildlife Refuge manages wildlife at a number of salt ponds that the Cargill Corporation currently operates for salt production. A number of these ponds probably will be purchased by the USFWS. With acquisition, the USFWS will be responsible for maintenance or restoration of thousands of hectares of wetlands, an extremely complex...
Trends in Dissolved Organic Carbon (DOC) in the Sacramento-San Joaquin Delta
Water from the Sacramento-San Joaquin Delta contains high concentrations of disinfection byproduct-forming (DBP-forming) materials when treated for potable use. DBPs form when dissolved organic compounds (DOC) in water react with disinfectants such as chlorine and ozone during the water treatment process. The amount of DBPs that form is a function of both the amount and source of the DOC, both of...
The role of the alien clam Corbicula fluminea in the regulation of organic carbon in the San Joaquin River watershed
Sources and fate of various forms of organic carbon in the Sacramento-San Joaquin Delta (Delta) and San Joaquin River watershed are of concern because of the importance of identifying the sources of carbon contributing to the oxygen depletion zone on the San Joaquin River near the city of Stockton, the need to understand the causes of the low primary and secondary production in the Delta, and the...
Processes Controlling Riverbank Filtration of Pathogens in the Russian River Basin, Sonoma County, California
The Sonoma County Water Agency (SCWA) supplies drinking water to municipalities and water districts in Sonoma and Marin Counties by diverting water from the alluvial aquifer underlying and adjacent to the Russian River. The U.S. Geological Survey, in cooperation with SCWA, is conducting an ongoing research program on water quality conditions in the Russian River and the physical and geochemical...