Heterosigma akashiwo collected from Seaplane Lagoon in San Francisco Bay on August 9, 2022. Video was taken with an ioLight 1mm microscope.
Keith Bouma-Gregson
Keith Bouma-Gregson is a Research Biologist at the California Water Science Center.
Keith researches algae and cyanobacteria and how they impact the flow of energy and cycling of nutrients through aquatic ecosystems. He has researched algae and freshwater harmful algal blooms (HABs) since 2012 and joined USGS in 2021. Keith uses a variety of methods, from metagenomics to remote sensing, to understand how algae and cyanobacteria impact water quality and food webs. The goal of his research is to identify the processes, and relevant spatial and temporal scales, that control the community composition of algae and cyanobacteria, and when blooms may produce toxins. With this knowledge, he hopes to improve models and sensors to predict when HABs will occur. Working with academic and agency collaborators in the USA and abroad, he strives to generate actionable information and create tools that can improve ecosystem management and inform water policy.
Professional Experience
2021-Present Biologist, U.S. Geological Survey
2019-2021 Freshwater Harmful Algal Bloom coordinator, California State Water Resources Control Board
2018-2019 Postdoctoral Researcher, UC Berkeley, Department of Earth and Planetary Science
Education and Certifications
Ph.D., University of California Berkeley, 2017, Department of Integrative Biology
M.S., University of Michigan, 2011, School of Environment and Sustainability
B.A., Westmont College, 2005, Sociology
Science and Products
Emergency Drought Barrier’s Impacts on cyanoHABs and Water Quality
Identifying the Source and Taxa That are Producing Microcystins Detected in San Francisco Bay
Biogeochemistry Group
Sampling Locations for the Water Quality of San Francisco Bay Project
Sampling Methods for the Water Quality of San Francisco Bay Project
Water Quality of San Francisco Bay Research and Monitoring Project
Monitoring Cyanotoxins in California's Sacramento-San Joaquin Delta: Fixed Stations and High-Resolution Mapping Surveys
High-Speed Mapping of Nutrient Distributions and Water Quality Survey - Lower South San Francisco Bay
Heterosigma akashiwo collected from Seaplane Lagoon in San Francisco Bay on August 9, 2022. Video was taken with an ioLight 1mm microscope.
Evaluation and refinement of chlorophyll-a algorithms for high-biomass blooms in San Francisco Bay (USA)
A simple approach to modeling light attenuation in the Sacramento-San Joaquin Delta using commonly available data
Science and Products
- Science
Emergency Drought Barrier’s Impacts on cyanoHABs and Water Quality
Drought is making the Delta Saltier. Less freshwater coming from watershed runoff and reservoir releases means that more salty water flows into the Sacramento San Joaquin Delta (Delta) from the Pacific Ocean. Changes in Delta salinity have far-reaching impacts, affecting the water supply for agriculture, drinking, wildlife, and Delta ecosystems.Identifying the Source and Taxa That are Producing Microcystins Detected in San Francisco Bay
Microcystins are toxins produced by cyanobacteria (previously known as blue-green algae ) that are harmful to humans and other animals. In 2012, microcystins began to be detected in San Francisco Bay (SFB). This was unexpected because most microcystin producing cyanobacteria live in freshwater. On-going microcystin-related work has focused on monitoring the presence of microcystins in water and...Biogeochemistry Group
The Biogeochemistry (BGC) Group uses an interdisciplinary approach to address surface water quality issues and food web dynamics throughout California, particularly in the Sacramento-San Joaquin Delta and San Francisco Bay.Sampling Locations for the Water Quality of San Francisco Bay Project
Since 1969, the Water Quality of San Francisco Bay Research and Monitoring Project has conducted water-column sampling along the deep channel of the San Francisco Bay-Delta system. Learn more about when and where we collect data.Sampling Methods for the Water Quality of San Francisco Bay Project
The Water Quality of San Francisco Bay Research and Monitoring Project measures changes in water quality along the deep channel of the San Francisco Bay-Delta system using submersible sensors and discrete water samples. Learn more about how we collect and measure water-quality data.Water Quality of San Francisco Bay Research and Monitoring Project
Since 1969, the U.S. Geological Survey has maintained a research project in the San Francisco Bay-Delta system to measure and understand how estuarine systems and tidal river deltas function and change in response to hydro-climatic variability and human activities.Monitoring Cyanotoxins in California's Sacramento-San Joaquin Delta: Fixed Stations and High-Resolution Mapping Surveys
California’s Sacramento-San Joaquin River Delta (Delta) provides drinking water to about 30 million people and irrigation water to the agriculturally rich Central Valley. The Delta is also home to numerous threatened and endangered native species. The health of the Delta's aquatic ecosystems, and fish in particular, have long been in a state of decline. This is associated with decreasing...High-Speed Mapping of Nutrient Distributions and Water Quality Survey - Lower South San Francisco Bay
This project aims to characterize spatial heterogeneity for key water quality parameters, and pilot the use of underway-flowthrough mapping of biogeochemical properties as a cost-effective approach to monitoring. - Multimedia
Heterosigma akashiwo collected from Seaplane Lagoon in San Francisco BayHeterosigma akashiwo collected from Seaplane Lagoon in San Francisco BayHeterosigma akashiwo collected from Seaplane Lagoon in San Francisco Bay
Heterosigma akashiwo collected from Seaplane Lagoon in San Francisco Bay on August 9, 2022. Video was taken with an ioLight 1mm microscope.
Heterosigma akashiwo collected from Seaplane Lagoon in San Francisco Bay on August 9, 2022. Video was taken with an ioLight 1mm microscope.
- Publications
Evaluation and refinement of chlorophyll-a algorithms for high-biomass blooms in San Francisco Bay (USA)
A massive bloom of the raphidophyte Heterosigma akashiwo occurred in summer 2022 in San Francisco Bay, causing widespread ecological impacts including events of low dissolved oxygen and mass fish kills. The rapidly evolving bloom required equally rapid management response, leading to the use of near-real-time image analysis of chlorophyll from the Ocean and Land Colour Instrument (OLCI) aboard SenAuthorsRaphael M. Kudela, David B. Senn, Emily T. Richardson, Keith Bouma-Gregson, Brian A. Bergamaschi, Lawrence SimA simple approach to modeling light attenuation in the Sacramento-San Joaquin Delta using commonly available data
The diffuse attenuation coefficient of photosynthetically active radiation (KdPAR) is commonly used to predict light attenuation in aquatic productivity models, but obtaining measurements of PAR to compute KdPAR is difficult. In situ calculations of KdPAR require multiple measurements of PAR through the water column, and these measurements are infeasible for real-time recording. Instead, predictivAuthorsEmily T. Richardson, Keith Bouma-Gregson, Katy O'Donnell, Brian A. Bergamaschi - News