Modeling the effect of habitat availability and quality on endangered winter-run Chinook salmon (Oncorhynchus tshawytscha) production in the Sacramento Valley

Ecological Modelling (Elsevier) | March 13th, 2021

Reconciliation between water uses and sustaining aquatic species populations requires an effort to identify and quantify essential habitat characteristics for ecosystem h

Reconciliation between water uses and sustaining aquatic species populations requires an effort to identify and quantify essential habitat characteristics for ecosystem health and valuation methods to predict ecosystem response to restoration actions. This process is particularly challenging for anadromous fish species such as California's Sacramento River winter-run Chinook salmon, due to their limited geographic range and diverse life history habitat requirements. Tools, such as life-cycle models, are needed to manage population dynamics and quantify the composite effects of processes across space and time. Nevertheless, complex institutions can hinder result interpretation and communication, and limit model use in decision-making. This paper focuses on the federally endangered and endemic Sacramento River winter-run Chinook (Oncorhynchus tshawytscha) by developing a Winter-Run Habitat-based Population Model (WRHAP). WRHAP is a conceptual, freshwater rearing stage model that includes alternative rearing habitats reported in the literature (e.g., floodplains, off-channel and tributaries), defines rules of habitat use based on instream conditions, and incorporates a juvenile growth module that combines bioenergetics modeling with empirical growth rates. Model outputs reasonably follow observed out-migration patterns and provide a realistic smolt size distribution arriving at the San Francisco Bay. This effort demonstrates the importance of currently “non-critical” habitats (as defined by the Endangered Species Act) for juvenile development, with floodplain habitat contributing to a quarter of out-migrating biomass (despite < 18% availability and <10% of total rearing days), and off-channel growth being one of the most sensitive parameters (explaining ~13% of average juvenile weight variance). The model shows the utility of a simple population model to explore relationships between habitat quality/quantity and juvenile development, and to assist water/environmental management and decision-making processes focused on species recovery.

National Marine Fisheries Service Biological Opinion for the Long-Term Operations of the Central Valley Project and State Water Project

National Marine Fisheries Service (NMFS) | June 3rd, 2009

The purpose of this document is to present NOAA’s National Marine Fisheries Service’s (NMFS) biological and conference opinion (Opinion), about whether the U.S. Burea

The purpose of this document is to present NOAA’s National Marine Fisheries Service’s (NMFS) biological and conference opinion (Opinion), about whether the U.S. Bureau of Reclamation’s (Reclamation) proposed long-term operations of the Central Valley Project (CVP), operated in coordination with the State Water Project (SWP; hereafter referred to as CVP/SWP operations, the proposed action, or the project), is likely to jeopardize the continued existence of the following species: Endangered Sacramento River winter-run Chinook salmon (Oncorhynchus tshawytscha, hereafter referred to as winter-run) Threatened Central Valley spring-run Chinook salmon (O. tshawytscha, hereafter referred to as spring-run) Threatened Central Valley (CV) steelhead (O. mykiss) Threatened Central California Coast (CCC) steelhead (O. mykiss) Threatened Southern Distinct Population Segment (DPS) of North American green sturgeon (Acipenser medirostris, hereafter referred to as Southern DPS of green sturgeon) Endangered Southern Resident killer whales (Orcinus orca, hereafter referred to as Southern Residents) or destroy or adversely modify the designated critical habitat of the above salmon and steelhead species, or proposed critical habitat for Southern DPS of green sturgeon. This Opinion is based on the best scientific and commercial information available.

Native and alien fishes in a California estuarine marsh: twenty-one years of changing assemblages

American Fisheries Society (AFS) | September 30th, 2002

We used monthly otter trawling and beach seining to sample the fishes of Suisun Marsh in the San Francisco Estuary from 1979 to 1999. We collected nearly 173,000 fish, mo

We used monthly otter trawling and beach seining to sample the fishes of Suisun Marsh in the San Francisco Estuary from 1979 to 1999. We collected nearly 173,000 fish, mostly young of the year, representing 28 native species and 25 alien species. Catch data were related to temperature, salinity, water transparency, and several measures of freshwater inflow into the marsh. Species abundance and distribution within the marsh were the product of several interacting factors: (1) the timing and place of reproduction of the abundant resident species, (2) past reproductive success, (3) habitat differences among sloughs, and (4) physiological tolerance. We did not find consistent groups of potentially interacting species, although some native species showed weak concordance in abundance. The lack of persistent fish assemblages is related to the naturally fluctuating environmental conditions of the estuary, the overall decline in fish abundance through time, and the frequent invasions of alien fishes and invertebrates. Our results suggest that the fish assemblages in Suisun Marsh will continue to be unpredictable until estuarine processes approach their historic range of variability and alien invasions are halted.

Natural Resources Defense Council v. Kempthorne, Order Granting in Part and Denying in Part Plaintiffs’ Motion for Summary Judgment

United States District Court, Eastern District of California | May 7th, 2007

This case concerns the effect on a threatened species of fish, the Delta smelt (Hypomesus transpacificus) , of the coordinated operation of the federally managed Central

This case concerns the effect on a threatened species of fish, the Delta smelt (Hypomesus transpacificus) , of the coordinated operation of the federally managed Central Valley Project ("CVP") and the State of California's State Water Project *2 ("SWP"), among the world's largest water diversion projects. Both projects divert large volumes of water from the California Bay (Sacramento - San Joaquin) Delta ("Delta") and use the Delta to store water.

North Coast Regional Water Quality Control Board Fact Sheet

California State Water Resources Control Board (SWRCB) | March 1st, 2010

The North Coast Region receives more precipitation than any other part of California. Abundant in surface water and groundwater resources, the North Coast Regio

The North Coast Region receives more precipitation than any other part of California. Abundant in surface water and groundwater resources, the North Coast Region constitutes only about 12 percent of the area of California but produces about 40 percent of the annual runoff. Encompassing some 19,390 square miles, including 340 miles of coastline and remote wilderness, urban and agricultural areas, the North Coast Region is divided into two natural drainage basins—the Klamath River Basin and the North Coastal Basin.

North Delta Water Management Program

California Department of Water Resources (DWR) | March 1st, 1988

Water management issues surrounding the Sacramento-San Joaquin Delta continue to challenge water resource planners in California. Many agree there are problems and urge

Water management issues surrounding the Sacramento-San Joaquin Delta continue to challenge water resource planners in California. Many agree there are problems and urge that they be corrected, but a consensus on how best to solve them has not yet been reached. Problems include frequent flooding due to unstable levees and constricted channels, flow patterns that are unfavorable for fish and water quality, and water level and circulation patterns that hinder irrigation. During the last several years, various water resources problems have been corrected through application of the public environmental documentation and regulatory permit process. This process has also shown the importance of Federal permit regulations in governing projects in the Delta estuary. To facilitate planning, the estuary has been divided into three study areas for evaluation of problems and needs unique to each area -- North, South, and West. This report discusses concepts for a North Delta Water Management Program. The long-term planning and environmental documentation process will includeother reports and will take about three years to complete. Planning flexibility afforded by the environmental documentation and regulatory permit process is expected to allow many of the concerns surrounding Delta water management to be resolved.

Not All Rivers Are Created Equal: The Importance of Spring-Fed Rivers under a Changing Climate

Water (MDPI) | June 12th, 2021

In the Western United States, volcanic spring-fed rivers are anticipated to become increasingly more important for salmonids and other native fishes, as these rivers wil

In the Western United States, volcanic spring-fed rivers are anticipated to become increasingly more important for salmonids and other native fishes, as these rivers will retain cold-water habitats as the climate warms. Despite this, little is known about the hydro-biogeochemical interactions within these ecosystems. A review of existing literature on spring-fed rivers, coupled with a decade of research on volcanic spring-fed rivers of northern California, finds that these systems are exceptionally productive and exhibit stable environmental conditions. These unique conditions stem from hydrogeologic processes typical of young volcanic terrains. Aquatic macrophytes, common to some nutrient-rich spring-fed systems, play a disproportionate role in hydrologic and geomorphic processes by facilitating ecological interactions and velocity conditions that improve juvenile salmonid growth. We find that volcanic spring-fed rivers are also resilient to climate change, due not only to their ability to dampen water temperature changes through deep groundwater flow but also because of their nutrient-driven high ecosystem productivity, which may enable cold-water species to metabolically compensate for marginal increases in water temperature. Understanding the fundamental geomorphic and ecological differences between these rare ecosystems and their numerically dominant runoff rivers is essential for developing long-term conservation strategies for cold-water species under a rapidly changing climate.

Notice of Entry of Order for Implementation of Preliminary Injunction – Case No. Bcv-22-103220-Gap, Bring Back the Kern et al v. City of Bakersfield et al

Superior Court of California, County of Kern | November 14th, 2023

Observations of the spawning ecology of the imperiled Clear Lake Hitch

California Department of Fish and Wildlife (CDFW) | October 13th, 2019

Outmigration survival of wild Chinook salmon smolts through the Sacramento River during historic drought and high water conditions

Environmental Biology of Fishes (Springer) | January 27th, 2020