Selenium Cycling in Salton Sea Wetlands Active
The effect of selenium toxicity on wildlife has been known for more than 50 years. This issue drew particular attention in the 1980s when embryo deformity and mortality was observed in birds at a wildlife refuge in California. Harmful effects from selenium were determined to be connected to irrigation drainage water.
As a result, an effort began to monitor levels of selenium in irrigation drainage water throughout the western United States. One location, studied by both the U.S. Geological Survey and U.S. Fish and Wildlife Service, was the Salton Sea and its surrounding area. The Salton Sea is a shallow, saline, drainage lake at the southern end California. It lies between, and within, the Imperial and Coachella Valleys.
In the past decade, Salton Sea water elevation has declined due to drought, the lining of canals, and changes in the management of the Colorado River. This has resulted in the creation of new wetlands caused by drains and rivers no longer reaching the Salton Sea. Because these wetlands are new, the effect and possible toxicity of levels of selenium and related metals needs to be assessed. This study will help evaluate whether such wetlands are suitable for migratory and endangered birds.
The initial phase of this work consisted of a data compilation and review assessment of selenium in the Salton Sea region. This work gathered more than 7,000 measurements of selenium in water, sediment, and biota. The information was then compiled into two data releases for ease of access. A forthcoming scientific investigations report (SIR) will further evaluate these data.
The SIR will also be used to develop a phased study plan designed to assess potential selenium risks to the federally endangered bird species, the Yuma Ridgway’s Rail (Rallus obsoletus yumanensis) in wetlands around the southern part of the Salton Sea.
Approach and Timeline
The first phase of this work (Phase I) consisted of pilot work that is now complete. This pilot work was designed to inform more detailed sample collection in the second phase (Phase II). Phase II is now ongoing. The data from the first two phases will then be used in phase three (Phase III) – a selenium risk assessment model for the Yuma Ridgway’s Rail.
Phase I sampling was done in 2021 and 2022; Phase II started in January 2023 and is ongoing. Phase III is anticipated to start in late 2024.
Science Plan
This study uses different water sources and strategies to gather information on selenium in selected wetlands. Water and sediment data collection focuses on selenium, nutrients, and associated trace elements. These data will provide information on how selenium may move from dissolved forms in the inflowing drain water into forms that may find their way into wetland food webs.
Water and sediment sample collection is tightly paired with biological sample collection at the base of wetland food webs. This includes Yuma Ridgway’s Rail sampling by the USGS cooperative research unit at the University of Idaho. We will use this information to better understand selenium within these dynamic wetland environments. These data will help determine whether the wetlands are viable long-term habitats for perennial and migratory wildlife.
Results and benefits
Data collected in this project will be compiled in one or more data releases. Risk assessment modeling will be outlined in an interpretive report. The report will assess the selenium information collected in Phase I and Phase II. Prior to publication of the report, several stakeholder meetings will be held with federal, state, and local partners in Coachella and Imperial Valleys. The aim of these meetings will be to outline the report’s findings. These data will serve in the guidance of managements decisions regarding the ecology and long-term sustainability of Salton Sea wetlands.
Below are publications associated with this project.
Selenium hazards in the Salton Sea environment—Summary of current knowledge to inform future wetland management
U.S. Geological Survey water science strategy—Observing, understanding, predicting, and delivering water science to the Nation
Patterns of metal composition and biological condition and their association in male common carp across an environmental contaminant gradient in Lake Mead National Recreation Area, Nevada and Arizona, USA
Irrigation-induced contamination of water, sediment, and biota in the western United States-synthesis of data from the National Irrigation Water Quality Program
Agricultural drainwater effects on wildlife in central California
Detailed study of water quality, bottom sediment, and biota associated with irrigation drainage in the Salton Sea area, California, 1988-90
Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the Salton Sea area, California, 1986-87
Below are news stories associated with this project.
Below are partners associated with this project.
- Overview
The effect of selenium toxicity on wildlife has been known for more than 50 years. This issue drew particular attention in the 1980s when embryo deformity and mortality was observed in birds at a wildlife refuge in California. Harmful effects from selenium were determined to be connected to irrigation drainage water.
As a result, an effort began to monitor levels of selenium in irrigation drainage water throughout the western United States. One location, studied by both the U.S. Geological Survey and U.S. Fish and Wildlife Service, was the Salton Sea and its surrounding area. The Salton Sea is a shallow, saline, drainage lake at the southern end California. It lies between, and within, the Imperial and Coachella Valleys.
In the past decade, Salton Sea water elevation has declined due to drought, the lining of canals, and changes in the management of the Colorado River. This has resulted in the creation of new wetlands caused by drains and rivers no longer reaching the Salton Sea. Because these wetlands are new, the effect and possible toxicity of levels of selenium and related metals needs to be assessed. This study will help evaluate whether such wetlands are suitable for migratory and endangered birds.
The initial phase of this work consisted of a data compilation and review assessment of selenium in the Salton Sea region. This work gathered more than 7,000 measurements of selenium in water, sediment, and biota. The information was then compiled into two data releases for ease of access. A forthcoming scientific investigations report (SIR) will further evaluate these data.
The SIR will also be used to develop a phased study plan designed to assess potential selenium risks to the federally endangered bird species, the Yuma Ridgway’s Rail (Rallus obsoletus yumanensis) in wetlands around the southern part of the Salton Sea.
Approach and Timeline
The first phase of this work (Phase I) consisted of pilot work that is now complete. This pilot work was designed to inform more detailed sample collection in the second phase (Phase II). Phase II is now ongoing. The data from the first two phases will then be used in phase three (Phase III) – a selenium risk assessment model for the Yuma Ridgway’s Rail.
Phase I sampling was done in 2021 and 2022; Phase II started in January 2023 and is ongoing. Phase III is anticipated to start in late 2024.
Science Plan
This study uses different water sources and strategies to gather information on selenium in selected wetlands. Water and sediment data collection focuses on selenium, nutrients, and associated trace elements. These data will provide information on how selenium may move from dissolved forms in the inflowing drain water into forms that may find their way into wetland food webs.
Water and sediment sample collection is tightly paired with biological sample collection at the base of wetland food webs. This includes Yuma Ridgway’s Rail sampling by the USGS cooperative research unit at the University of Idaho. We will use this information to better understand selenium within these dynamic wetland environments. These data will help determine whether the wetlands are viable long-term habitats for perennial and migratory wildlife.
Results and benefits
Data collected in this project will be compiled in one or more data releases. Risk assessment modeling will be outlined in an interpretive report. The report will assess the selenium information collected in Phase I and Phase II. Prior to publication of the report, several stakeholder meetings will be held with federal, state, and local partners in Coachella and Imperial Valleys. The aim of these meetings will be to outline the report’s findings. These data will serve in the guidance of managements decisions regarding the ecology and long-term sustainability of Salton Sea wetlands.
- Publications
Below are publications associated with this project.
Selenium hazards in the Salton Sea environment—Summary of current knowledge to inform future wetland management
Quaternary marine and continental shales in the western United States are sources of selenium that can be loaded into the aquatic environment through mining, agricultural, and energy production processes. The mobilization of selenium from shales through agricultural irrigation has been recognized since the 1930s; however, discovery of deformities in birds and other wildlife using agricultural habiAuthorsMichael R. Rosen, Susan E.W. De La Cruz, Krishangi D. Groover, Isa Woo, Sarah A. Roberts, Melanie J. Davis, Cristiana Y. AntoninoU.S. Geological Survey water science strategy—Observing, understanding, predicting, and delivering water science to the Nation
Executive SummaryThis report expands the Water Science Strategy that began with the USGS Science Strategy, “Facing Tomorrow’s Challenges—U.S. Geological Survey Science in the Decade 2007–2017” (U.S. Geological Survey, 2007). This report looks at the relevant issues facing society and develops a strategy built around observing, understanding, predicting, and delivering water science for the next 5AuthorsEric J. Evenson, Randall C. Orndorff, Charles D. Blome, John Karl Böhlke, Paul K. Hershberger, Victoria E. Langenheim, Gregory J. McCabe, Scott E. Morlock, Howard W. Reeves, James P. Verdin, Holly S. Weyers, Tamara M. WoodPatterns of metal composition and biological condition and their association in male common carp across an environmental contaminant gradient in Lake Mead National Recreation Area, Nevada and Arizona, USA
There is a contaminant gradient in Lake Mead National Recreation Area (LMNRA) that is partly driven by municipal and industrial runoff and wastewater inputs via Las Vegas Wash (LVW). Adult male common carp (Cyprinus carpio; 10 fish/site) were collected from LVW, Las Vegas Bay (receiving LVW flow), Overton Arm (OA, upstream reference), and Willow Beach (WB, downstream) in March 2008. Discriminant fAuthorsReynaldo Patiño, Michael R. Rosen, E.L. Orsak, Steven L. Goodbred, Thomas W. May, David A. Alvarez, Kathy R. Echols, Carla M. Wieser, Shane Ruessler, L. TorresIrrigation-induced contamination of water, sediment, and biota in the western United States-synthesis of data from the National Irrigation Water Quality Program
In October 1985 the U.S. Department of the Interior (DOI), through the National Irrigation Water Quality Program (NIWQP), began a series of field investigations at 26 areas in the Western United States to determine whether irrigation drainage has had harmful effects on fish, wildlife, and humans or has reduced beneficial uses of water. In 1992 NIWQP initiated the Data Synthesis Project to evaluateAuthorsRalph L. Seiler, Joseph P. Skorupa, David L. Naftz, B. Thomas NolanAgricultural drainwater effects on wildlife in central California
In California's San Joaquin Valley and in numerous other agricultural areas in the western U.S., irrigation wastewater may accumulate in confined shallow aquifers, eventually rising to levels that adversely affect crops. To sustain long-term agricultural productivity in these regions, systems for the drainage and disposal of this subsurface wastewater must be installed.1,2 the drained water may cAuthorsHarry M. Ohlendorf, Roger L. HothemDetailed study of water quality, bottom sediment, and biota associated with irrigation drainage in the Salton Sea area, California, 1988-90
Results of a detailed study by the National Irrigation Water-Quality Program (NIWQP), U.S. Department of the Interior, indicate that factors controlling contaminant concentrations in subsurface irrigation drainwater in the Imperial Valley are soil characteristics, hydrology, and agricultural practices. Higher contaminant concentrations commonly were associated with clayey soils, which retard the mAuthorsJ. G. Setmire, R. A. Schroeder, J.N. Densmore, S.O. Goodbred, D. J. Audet, W.R. RadkeByReconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the Salton Sea area, California, 1986-87
Water, bottom sediment, and biota were sampled during 1986 and 1987 in the Salton Sea area to determine concentrations of trace elements and pesticides as part of the Department of Interior Irrigation Drainage Program. The sampling sites (12 water, 15 bottom sediment, and 5 biota) were located in the Coachella and Imperial Valleys. The focus of sampling was to determine the current or potential thAuthorsJ. G. Setmire, J.C. Wolfe, R. K. StroudBy - News
Below are news stories associated with this project.
- Partners
Below are partners associated with this project.