Anadromous Salmonids in the Delta: New Science 2006-2016

University of California, Davis (UC Davis) | July 1st, 2016

As juvenile salmon enter the Delta, they disperse among its complex channel network where they are subject to channel-specific processes that affect their rate of migrati

As juvenile salmon enter the Delta, they disperse among its complex channel network where they are subject to channel-specific processes that affect their rate of migration, vulnerability to predation, feeding success, growth rates, and ultimately, survival. In the decades before 2006, tools available to quantify growth, dispersal, and survival of juvenile salmon in this channel network were limited. Fortunately, thanks to technological advances, much has been learned over the past decade about the role of the Delta in the life cycle of juvenile salmon. One of the most important advances during the past decade has been the widespread adoption of acoustic telemetry techniques. Use of telemetry has shed light on how survival varies among alternative migration routes and the proportion of fish that use each migration route. Chemical and structural analysis have provided insights about when juveniles left their natal river and provided evidence of extended rearing in the brackish or saltwater regions of the Delta. New advancements in genetics now allow individuals captured by trawls to be assigned to specific runs. Detailed information about movement and survival in the Delta has spurred development of agent-based models of juvenile salmon that are coupled to hydrodynamic models. Although much has been learned, knowledge gaps remain about how very small juvenile salmon (fry and parr) use the Delta. Understanding how all life stages of juvenile salmon grow, rear, and survive in the Delta is critical for devising management strategies that support a diversity of life history strategies.

Analyses of Rotary Screw Trap Sampling of Migrating Juvenile Chinook Salmon in the Stanislaus River, 1996-2005

Delta Stewardship Council (Delta Council) | August 1st, 2006

Annual Report of Activities October 1, 2013 to September 30, 2014, American River Group (ARG)

Delta Stewardship Council (Delta Council) | September 30th, 2014

Anthropogenic carbon and ocean pH: Oceanography

Nature Portfolio (Springer Nature) | September 25th, 2003

Most carbon dioxide released into the atmosphere as a result of the burning of fossil fuels will eventually be absorbed by the ocean1, with potentially adverse co

Most carbon dioxide released into the atmosphere as a result of the burning of fossil fuels will eventually be absorbed by the ocean1, with potentially adverse consequences for marine biota. Here we quantify the changes in ocean pH that may result from this continued release of CO2 and compare these with pH changes estimated from geological and historical records. We find that oceanic absorption of CO2 from fossil fuels may result in larger pH changes over the next several centuries than any inferred from the geological record of the past 300 million years, with the possible exception of those resulting from rare, extreme events such as bolide impacts or catastrophic methane hydrate degassing.

Anthropogenic debris in seafood: Plastic debris and fibers from textiles in fish and bivalves sold for human consumption

Nature Portfolio (Springer Nature) | September 24th, 2015

The ubiquity of anthropogenic debris in hundreds of species of wildlife and the toxicity of chemicals associated with it has begun to raise concerns regarding the presenc

The ubiquity of anthropogenic debris in hundreds of species of wildlife and the toxicity of chemicals associated with it has begun to raise concerns regarding the presence of anthropogenic debris in seafood. We assessed the presence of anthropogenic debris in fishes and shellfish on sale for human consumption. We sampled from markets in Makassar, Indonesia and from California, USA. All fish and shellfish were identified to species where possible. Anthropogenic debris was extracted from the digestive tracts of fish and whole shellfish using a 10% KOH solution and quantified under a dissecting microscope. In Indonesia, anthropogenic debris was found in 28% of individual fish and in 55% of all species. Similarly, in the USA, anthropogenic debris was found in 25% of individual fish and in 67% of all species. Anthropogenic debris was also found in 33% of individual shellfish sampled. All of the anthropogenic debris recovered from fish in Indonesia was plastic, whereas anthropogenic debris recovered from fish in the USA was primarily fibers. Variations in debris types likely reflect different sources and waste management strategies between countries. We report some of the first findings of plastic debris in fishes directly sold for human consumption raising concerns regarding human health.

Assessing the Impact of Periodic Dredging on Macroinvertebrate Prey Availability for Benthic Foraging Fishes

U.S. Geological Survey (USGS) | July 1st, 2017

Due to its importance for special status fish, the San Francisco Bay (SFB) estuary has been designated as Essential Fish Habitat (EFH) under the Magnuson-Stevens Fishery

Due to its importance for special status fish, the San Francisco Bay (SFB) estuary has been designated as Essential Fish Habitat (EFH) under the Magnuson-Stevens Fishery Conservation and Management Act ([MSA; 16 U.S.C. 18559b)]. Within this estuary, benthic macroinvertebrate communities provide important prey resources for many economically significant fish species that rely on EFH. Periodic maintenance dredging can impact these infaunal communities; however, there is a lack of scientific information specific to SFB on the degree of benthic community disruption caused by dredging. In addition, rates of benthic community recolonization and recovery following dredging and subsequent effects on foraging fish are unknown. For this reason, it is difficult for regulatory and resource agencies to determine the impacts of maintenance dredging. Thus, the National Marine Fisheries Service (NMFS) and the consortium of agencies (US Environmental Protection Agency (EPA), US Army Corp of Engineers (USACE), San Francisco Regional Water Quality Control Board (SFRWQCB), and San Francisco Bay Conservation and Development Commission (BCDC)) comprising the San Francisco Bay Long Term Management Strategy for Dredging (LTMS) effort identified a study of dredging impacts on SFB fish foraging habitat as one of their highest priorities in their 2011 Programmatic EFH Agreement. 

Bay Delta Plan Phase 2 Workshop Summary Report

California State Water Resources Control Board (SWRCB) | January 1st, 2013

The California State Water Resources Control Board (Board) is tasked with updating the 2006 Water Quality Control Plan for the Bay-Delta Estuary (Bay-Delta Plan). The Boa

The California State Water Resources Control Board (Board) is tasked with updating the 2006 Water Quality Control Plan for the Bay-Delta Estuary (Bay-Delta Plan). The Board planning activities for this process have four phases. Phase 1 focused on San Joaquin River flow requirements and southern Delta water quality objectives. The current phase (Phase 2) focuses on fish and wildlife beneficial uses. Phase 3 will focus on modifications to water rights and Phase 4 will focus on the development and implementation of flow requirements for priority Delta tributaries. Phase 2 workshops were held to conduct discussions and generate information regarding the scientific and technical basis for considering potential changes to the Bay-Delta Plan. The workshops were informal; the Board did not take any official action and there was no sworn testimony. Information provided during the workshops will augment information developed through earlier reviews and will inform the Board members and staff on what, if any, changes should be made to the Bay-Delta Plan. Three workshops were held. Full workshop agendas are provided in Appendix A. 1. Ecosystem Changes and the Low Salinity Zone, September 5–6, 2012 – including the effects of the low salinity zone on various estuarine species, the interaction of salinity with non-flow related factors, and the identification of modeling or other tools that can be used to measure and reasonably protect estuarine habitat. 2. Bay-Delta Fishery Resources, October 1–2, 2012 – including flow, cold water pool, habitat, and water project operational constraints needed to reasonably protect Central Valley steelhead, Sacramento River winter-run, Central Valley late fall–run Chinook salmon, and pelagic species (including Delta smelt and longfin smelt); and the interaction of these issues with non-flow related factors. 3. Analytical Tools for Evaluating the Water Supply, Hydrodynamic, and Hydropower Effects of the Bay-Delta Plan, November 13–14, 2012 – including the CalSim II water supply model, DSM2 and RMA2 hydrodynamic models, Plexus hydropower model, and others as  applicable, together with results from applying these models to various scenarios.

Biennial Report of the Fish and Game Commission of California 1924-26

California Fish and Game Commission | June 30th, 1926

Biennial Report of the State Board of Fish Commissioners of the State of California for the Years 1886-1888

State of California | October 1st, 1888

Biennial Report of the State Board of Fish Commissioners of the State of California for the Years 1888-1890

State of California | October 1st, 1890