Hydrologic and Aquatic Ecology Studies at Clear Lake, California
The USGS California Water Science Center conducts a variety of research activities at Clear Lake, California, including surface-water monitoring and water quality and aquatic habitat studies.
Clear Lake is the largest natural lake entirely within California. It is in the California Coast Range, approximately 60 miles (100 kilometers) north of San Francisco Bay. The lake supports a wide variety of fish and bird species and is a very popular sport-fishing destination.
Water Quality
Clear Lake is hypereutrophic (has excess algal growth), and as such has a severe problem with harmful algal blooms (HABs). Excess algae and HABs can be detrimental to aquatic life because when the algae die, sink, and decay, the lake is deprived of the dissolved oxygen that fish need to breathe. A driving factor of these conditions are the nutrient loads being carried into the lake by soil erosion and the transport of sediment and dissolved nutrients via the lake’s tributaries. Nutrients are also recycled from the lake bed, especially when wind conditions drive sediments from the bed to the surface.
The USGS is monitoring and modeling the Clear Lake watershed to better understand these nutrient sources. USGS scientists are also studying the way in which nutrient dynamics affect the cycling, transport, and bioaccumulation of mercury in the Clear Lake food web. Quantifying the contributions of nutrients and mercury coming from the lake’s watershed is essential for effective remediation (restoration) through implementation of best management practices.
Clear Lake Hitch
The Clear Lake Hitch was formerly highly abundant and a staple food for the Pomo tribes of the Clear Lake region. The original abundance of this fish species is unknown but is believed to have declined 100-fold. To better understand Clear Lake Hitch behavior and habitat use, USGS biologists have conducted extensive sampling of the lake and its tributaries, as well as detailed analysis of various parts of the fish, including otoliths (ear bones), eye lenses, and fish muscle. These findings are important for identifying critical habitat, an important element of endangered species conservation and management.
Studying Threatened Fish Species in Clear Lake, CA
Monitoring and Modeling of Nutrients and Other Water-Quality Constituents in Tributaries to Clear Lake, California
Scotts Creek Nutrient Erosion Study, Lake County, California
Mercury studies at Sulphur Bank Mercury Mine and Clear Lake, California
The USGS California Water Science Center conducts a variety of research activities at Clear Lake, California, including surface-water monitoring and water quality and aquatic habitat studies.
Clear Lake is the largest natural lake entirely within California. It is in the California Coast Range, approximately 60 miles (100 kilometers) north of San Francisco Bay. The lake supports a wide variety of fish and bird species and is a very popular sport-fishing destination.
Water Quality
Clear Lake is hypereutrophic (has excess algal growth), and as such has a severe problem with harmful algal blooms (HABs). Excess algae and HABs can be detrimental to aquatic life because when the algae die, sink, and decay, the lake is deprived of the dissolved oxygen that fish need to breathe. A driving factor of these conditions are the nutrient loads being carried into the lake by soil erosion and the transport of sediment and dissolved nutrients via the lake’s tributaries. Nutrients are also recycled from the lake bed, especially when wind conditions drive sediments from the bed to the surface.
The USGS is monitoring and modeling the Clear Lake watershed to better understand these nutrient sources. USGS scientists are also studying the way in which nutrient dynamics affect the cycling, transport, and bioaccumulation of mercury in the Clear Lake food web. Quantifying the contributions of nutrients and mercury coming from the lake’s watershed is essential for effective remediation (restoration) through implementation of best management practices.
Clear Lake Hitch
The Clear Lake Hitch was formerly highly abundant and a staple food for the Pomo tribes of the Clear Lake region. The original abundance of this fish species is unknown but is believed to have declined 100-fold. To better understand Clear Lake Hitch behavior and habitat use, USGS biologists have conducted extensive sampling of the lake and its tributaries, as well as detailed analysis of various parts of the fish, including otoliths (ear bones), eye lenses, and fish muscle. These findings are important for identifying critical habitat, an important element of endangered species conservation and management.