Marissa Wulff
Marissa Wulff is a Biologist at the California Water Science Center.
Marissa Bauer Wulff is a biologist with the U.S. Geological Survey’s California Water Science Center, where she researches and assists in projects relating to aquatic biology and ecology. Marissa has been involved in ecosystem modeling for the Sacramento-San Joaquin Delta as well as flow-regime and aquatic mercury studies. Marissa is currently involved in research looking at the effects of climate change on selected fish species of the San Francisco Bay-Delta.
Science and Products
Aquatic Ecology Group
The California Water Science Center's Aquatic Ecology Group is making great strides in research and reporting.
Filter Total Items: 18
Santa Ana River Native Fish Population and Habitat Data, Santa Ana River, California, 2025 Santa Ana River Native Fish Population and Habitat Data, Santa Ana River, California, 2025
This dataset includes fish population and habitat data collected in 2025 to support development of the upper Santa Ana River Habitat Conservation Plan for the Santa Ana Sucker (Catostomus santaanae) and the Arroyo Chub (Gila orcuttii) in the Santa Ana River, California.
Growth, survival, and tag retention results from PIT tagging Santa Ana Sucker in a mesocosm experiment Growth, survival, and tag retention results from PIT tagging Santa Ana Sucker in a mesocosm experiment
The Santa Ana Sucker (Pantosteus santaanae) is a federally threatened species of ray-finned fishes endemic to the Santa Ana, San Gabriel, and Los Angeles Rivers in southern California. Seasonal limitations on conventional sampling and inconsistencies in survey methodologies have led to an incomplete understanding of Santa Ana Sucker population dynamics. Therefore, alternative sampling...
Development and efficiency of less intrusive survey methodologies for Santa Ana sucker (Pantosteus santaanae) monitoring Development and efficiency of less intrusive survey methodologies for Santa Ana sucker (Pantosteus santaanae) monitoring
The Santa Ana Sucker (Pantosteus santaanae) is a federally threatened species endemic to the Santa Ana, San Gabriel, and Los Angeles Rivers in southern California. Seasonal limitations on conventional sampling and inconsistencies in survey methodologies have led to an incomplete understanding of Santa Ana Sucker population dynamics. Therefore, alternative sampling methods that are not...
Abundance and Distribution of Fishes in Lower Blue Lake, Lake County, California Abundance and Distribution of Fishes in Lower Blue Lake, Lake County, California
Field data for fishes sampled using bottom and surface gill nets during daylight hours on October 22-24, 2024 in Lower Blue Lake, Lake county, California, USA. This data release includes the results of all measured environmental parameters and fish taxa included in the analysis.
Santa Ana River Native Fish Population and Habitat Data, Santa Ana River, California, 2024 Santa Ana River Native Fish Population and Habitat Data, Santa Ana River, California, 2024
This dataset includes fish population and habitat data collected in 2024 to support development of the upper Santa Ana River Habitat Conservation Plan for the Santa Ana Sucker (Catostomus santaanae) and the Arroyo Chub (Gila orcuttii) in the Santa Ana River, California.
Santa Ana River Native Fish Population and Habitat Data, Santa Ana River, California, 2023 Santa Ana River Native Fish Population and Habitat Data, Santa Ana River, California, 2023
This dataset includes 2023 reach fish data and reach habitat data collected to support development of the upper Santa Ana River Habitat Conservation Plan for the Santa Ana Sucker (Catostomus santaanae) and the Arroyo Chub (Gila orcuttii) in the Santa Ana River, California.
Filter Total Items: 19
Effect of passive integrated transponder tag size on survival, tag loss, and growth of Santa Ana Sucker Effect of passive integrated transponder tag size on survival, tag loss, and growth of Santa Ana Sucker
Objective The Santa Ana Sucker Pantosteus santaanae is endemic to southern California and is listed as threatened under the U.S. Endangered Species Act. Seasonal limitations on conventional sampling and inconsistencies in survey methodologies have led to an incomplete understanding of population dynamics. Alternative sampling methods have the potential to fill important knowledge gaps in...
Authors
Jordan Mae-Jean Buxton, Marissa L. Wulff, Brock Huntsman, Kai Palenscar, Brett Mills, Kerwin Russell, Alicia Ruan, Tevin Bui
Status of Clear Lake Hitch in Lower Blue Lake, Lake County, California Status of Clear Lake Hitch in Lower Blue Lake, Lake County, California
No abstract available.
Authors
Jordan Mae-Jean Buxton, Marissa L. Wulff, Veronica L. Violette, Danielle L. Palm, Matthew J. Young, Frederick Feyrer
Gillnet sampling methods for monitoring status and trends of Clear Lake Hitch in Clear Lake, Lake County, California Gillnet sampling methods for monitoring status and trends of Clear Lake Hitch in Clear Lake, Lake County, California
The Clear Lake Hitch (Lavinia exilicauda chi) is a minnow endemic to Clear Lake, Lake County, California. This species is listed as a threatened species under the California Endangered Species Act and has been petitioned for listing under the United States Endangered Species Act. In 2017, the U.S. Geological Survey, in cooperation with the U.S. Fish and Wildlife Service, initiated a...
Authors
Frederick Feyrer, Matthew J. Young, Brock Huntsman, Veronica Violette, Justin K. Clause, Jordan Buxton, Danielle Palm, Marissa L. Wulff, Jeff Gronemyer, Luis Santana
Post Carr Fire bioassessment data report, Whiskeytown National Recreation Area, Shasta County, California Post Carr Fire bioassessment data report, Whiskeytown National Recreation Area, Shasta County, California
The U.S. Geological Survey, in cooperation with the National Park Service, analyzed water and sediment chemistry, benthic macroinvertebrate assemblages, fish and amphibian assemblages, fish and invertebrate tissues, instream habitat characteristics, and sediment heterogeneity at 10 stream sites within Whiskeytown National Recreation Area, Shasta County, California, during August 2020, 2...
Authors
Marissa L. Wulff, Larry R. Brown, Veronica L. Violette
Estimating the benefits of floodplain restoration to juvenile Chinook salmon in the upper San Francisco Estuary, United States, under future climate scenarios Estimating the benefits of floodplain restoration to juvenile Chinook salmon in the upper San Francisco Estuary, United States, under future climate scenarios
Many river systems within the Central Valley of California have been disconnected from their floodplains, hypothesized to be partially responsible for declining Chinook salmon populations (Oncorhynchus tshawytscha). The primary floodplain of the system, Yolo By-Pass (known regionally as “Yolo Bypass”), offered an opportunity to examine whether improved connectivity between the floodplain...
Authors
Brock M. Huntsman, Marissa L. Wulff, Noah Knowles, Ted Sommer, Frederick V. Feyrer, Larry R. Brown
Evaluation of extinction risk for stream fishes within an urban riverscape using population viability analysis Evaluation of extinction risk for stream fishes within an urban riverscape using population viability analysis
1. The Santa Ana River in the Los Angeles region of California demonstrates common habitat degradation symptoms that are characteristic of the urban stream syndrome. These impacts have altered the Santa Ana River community structure, with few species as impacted as the native Santa Ana sucker (sucker; Pantosteus santaanae). 2. Consequently, a recovery plan developed for sucker identified...
Authors
Brock Huntsman, Kai Palenscar, Kerwin Russell, Brett Mills, Chris Jones, William Ota, Kurt E. Anderson, Heather Dyer, Fitsum Abadi, Marissa L. Wulff
Non-USGS Publications**
Pintor, L. M., Sih, A. and Bauer, M. L. (2008), Differences in aggression, activity and boldness between native and introduced populations of an invasive crayfish. Oikos, 117: 1629–1636. doi:10.1111/j.1600-0706.2008.16578.x
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
Aquatic Ecology Group
The California Water Science Center's Aquatic Ecology Group is making great strides in research and reporting.
Filter Total Items: 18
Santa Ana River Native Fish Population and Habitat Data, Santa Ana River, California, 2025 Santa Ana River Native Fish Population and Habitat Data, Santa Ana River, California, 2025
This dataset includes fish population and habitat data collected in 2025 to support development of the upper Santa Ana River Habitat Conservation Plan for the Santa Ana Sucker (Catostomus santaanae) and the Arroyo Chub (Gila orcuttii) in the Santa Ana River, California.
Growth, survival, and tag retention results from PIT tagging Santa Ana Sucker in a mesocosm experiment Growth, survival, and tag retention results from PIT tagging Santa Ana Sucker in a mesocosm experiment
The Santa Ana Sucker (Pantosteus santaanae) is a federally threatened species of ray-finned fishes endemic to the Santa Ana, San Gabriel, and Los Angeles Rivers in southern California. Seasonal limitations on conventional sampling and inconsistencies in survey methodologies have led to an incomplete understanding of Santa Ana Sucker population dynamics. Therefore, alternative sampling...
Development and efficiency of less intrusive survey methodologies for Santa Ana sucker (Pantosteus santaanae) monitoring Development and efficiency of less intrusive survey methodologies for Santa Ana sucker (Pantosteus santaanae) monitoring
The Santa Ana Sucker (Pantosteus santaanae) is a federally threatened species endemic to the Santa Ana, San Gabriel, and Los Angeles Rivers in southern California. Seasonal limitations on conventional sampling and inconsistencies in survey methodologies have led to an incomplete understanding of Santa Ana Sucker population dynamics. Therefore, alternative sampling methods that are not...
Abundance and Distribution of Fishes in Lower Blue Lake, Lake County, California Abundance and Distribution of Fishes in Lower Blue Lake, Lake County, California
Field data for fishes sampled using bottom and surface gill nets during daylight hours on October 22-24, 2024 in Lower Blue Lake, Lake county, California, USA. This data release includes the results of all measured environmental parameters and fish taxa included in the analysis.
Santa Ana River Native Fish Population and Habitat Data, Santa Ana River, California, 2024 Santa Ana River Native Fish Population and Habitat Data, Santa Ana River, California, 2024
This dataset includes fish population and habitat data collected in 2024 to support development of the upper Santa Ana River Habitat Conservation Plan for the Santa Ana Sucker (Catostomus santaanae) and the Arroyo Chub (Gila orcuttii) in the Santa Ana River, California.
Santa Ana River Native Fish Population and Habitat Data, Santa Ana River, California, 2023 Santa Ana River Native Fish Population and Habitat Data, Santa Ana River, California, 2023
This dataset includes 2023 reach fish data and reach habitat data collected to support development of the upper Santa Ana River Habitat Conservation Plan for the Santa Ana Sucker (Catostomus santaanae) and the Arroyo Chub (Gila orcuttii) in the Santa Ana River, California.
Filter Total Items: 19
Effect of passive integrated transponder tag size on survival, tag loss, and growth of Santa Ana Sucker Effect of passive integrated transponder tag size on survival, tag loss, and growth of Santa Ana Sucker
Objective The Santa Ana Sucker Pantosteus santaanae is endemic to southern California and is listed as threatened under the U.S. Endangered Species Act. Seasonal limitations on conventional sampling and inconsistencies in survey methodologies have led to an incomplete understanding of population dynamics. Alternative sampling methods have the potential to fill important knowledge gaps in...
Authors
Jordan Mae-Jean Buxton, Marissa L. Wulff, Brock Huntsman, Kai Palenscar, Brett Mills, Kerwin Russell, Alicia Ruan, Tevin Bui
Status of Clear Lake Hitch in Lower Blue Lake, Lake County, California Status of Clear Lake Hitch in Lower Blue Lake, Lake County, California
No abstract available.
Authors
Jordan Mae-Jean Buxton, Marissa L. Wulff, Veronica L. Violette, Danielle L. Palm, Matthew J. Young, Frederick Feyrer
Gillnet sampling methods for monitoring status and trends of Clear Lake Hitch in Clear Lake, Lake County, California Gillnet sampling methods for monitoring status and trends of Clear Lake Hitch in Clear Lake, Lake County, California
The Clear Lake Hitch (Lavinia exilicauda chi) is a minnow endemic to Clear Lake, Lake County, California. This species is listed as a threatened species under the California Endangered Species Act and has been petitioned for listing under the United States Endangered Species Act. In 2017, the U.S. Geological Survey, in cooperation with the U.S. Fish and Wildlife Service, initiated a...
Authors
Frederick Feyrer, Matthew J. Young, Brock Huntsman, Veronica Violette, Justin K. Clause, Jordan Buxton, Danielle Palm, Marissa L. Wulff, Jeff Gronemyer, Luis Santana
Post Carr Fire bioassessment data report, Whiskeytown National Recreation Area, Shasta County, California Post Carr Fire bioassessment data report, Whiskeytown National Recreation Area, Shasta County, California
The U.S. Geological Survey, in cooperation with the National Park Service, analyzed water and sediment chemistry, benthic macroinvertebrate assemblages, fish and amphibian assemblages, fish and invertebrate tissues, instream habitat characteristics, and sediment heterogeneity at 10 stream sites within Whiskeytown National Recreation Area, Shasta County, California, during August 2020, 2...
Authors
Marissa L. Wulff, Larry R. Brown, Veronica L. Violette
Estimating the benefits of floodplain restoration to juvenile Chinook salmon in the upper San Francisco Estuary, United States, under future climate scenarios Estimating the benefits of floodplain restoration to juvenile Chinook salmon in the upper San Francisco Estuary, United States, under future climate scenarios
Many river systems within the Central Valley of California have been disconnected from their floodplains, hypothesized to be partially responsible for declining Chinook salmon populations (Oncorhynchus tshawytscha). The primary floodplain of the system, Yolo By-Pass (known regionally as “Yolo Bypass”), offered an opportunity to examine whether improved connectivity between the floodplain...
Authors
Brock M. Huntsman, Marissa L. Wulff, Noah Knowles, Ted Sommer, Frederick V. Feyrer, Larry R. Brown
Evaluation of extinction risk for stream fishes within an urban riverscape using population viability analysis Evaluation of extinction risk for stream fishes within an urban riverscape using population viability analysis
1. The Santa Ana River in the Los Angeles region of California demonstrates common habitat degradation symptoms that are characteristic of the urban stream syndrome. These impacts have altered the Santa Ana River community structure, with few species as impacted as the native Santa Ana sucker (sucker; Pantosteus santaanae). 2. Consequently, a recovery plan developed for sucker identified...
Authors
Brock Huntsman, Kai Palenscar, Kerwin Russell, Brett Mills, Chris Jones, William Ota, Kurt E. Anderson, Heather Dyer, Fitsum Abadi, Marissa L. Wulff
Non-USGS Publications**
Pintor, L. M., Sih, A. and Bauer, M. L. (2008), Differences in aggression, activity and boldness between native and introduced populations of an invasive crayfish. Oikos, 117: 1629–1636. doi:10.1111/j.1600-0706.2008.16578.x
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.