Pesticide and nutrient inputs from human activities are present in the Sacramenot-San Joaquin Bay-Delta, but the impact of these stressors together on algae is not well known. This research will examine the impacts of herbicides and nutrients on the growth and stress responses of phytoplankton and cyanobacteria present in the San Francisco Estuary. The algae in the delta are diverse with critical ecological effects, ranging from toxin-producing cyanobacteria that form hazardous algal blooms to benthic diatoms and green algae that make up the bulk of the aquatic food web. Contaminants and herbicides can cause changes in algae cellular health which may impact population growth. Understanding algal sub-lethal stress responses will improve our understanding of stressors on the bay-delta food web and bloom formation.
The goal of this research is to better understand how climate change will affect fishes with different life histories and habitat associations across the San Francisco Estuary. Existing datasets will be incorporated in synthetic analyses and cutting-edge statistical models to identify fish community responses to climate, flows, and habitats along the estuarine salinity gradient. This synthesis-science project will use rich long-term datasets that have been collected by Bay-Delta researchers for decades that will then be analyzed in a reproducible and open science framework. It will also support efforts by the Interagency Ecological Program’s Climate Change Project Work Team.
This study will investigate fish swim performance in response to temperature, using salmon and two of its known predators: largemouth bass and Sacramento pikeminnow. The researcher will assess swim performance metrics and predation risk inside and outside the ideal thermal range of each species to determine if a temperature advantage predicts salmon survival in predation scenarios. This project’s results will provide a mechanistic understanding of how temperature stress may influence mortality risk of juvenile Chinook salmon through predation, which will offer a more holistic perspective on the management of this species
This project focuses on nitrogen and carbon cycling within the Bay-Delta, both before and after planned 2021 upgrades to the Sacramento Regional Wastewater Treatment Plant (SRWTP). We will measure in situ benthic nitrate (NO3- ) and oxygen (O2) fluxes using a new non-invasive technique, which provides high frequency continuous data over a much larger sediment surface area than traditional methods. The SRTWP currently represents one of the largest point sources of nitrogen to the Bay-Delta, with the upgrades projected to cut nitrogen outputs from the plant by ~65%. This project will help assess the efficacy of this major management action and our results will add to biogeochemical models for the Bay-Delta.
