Images

Crown gathered at 2025 Tahoe Summit. The Lake Tahoe Summit is an annual event that brings local, federal, and state leaders together to discuss ways to protect Lake Tahoe and strengthen the partnership underlying the Lake Tahoe Environmental Improvement Program. 

USGS booth at 2025 Tahoe Summit. Pictured from left, Sara Doyle (NV WSC), Zach Hood (NV WSC), David Smith (NV WSC), Ed Parvin (CAWSC) and Mark Dickman (CAWSC). Photograph by Ramon Naranjo (NV WSC) on 8/6/25.

A field in California's Central Valley. This is being used to represent the Central Valley Hydrologic Model, version 2.

Klamath River Basin straddles northern California and southern Oregon. The Klamath River empties into the Pacific Ocean just below the Oregon/California border.

Water availability in the Klamath Basin is shaped by three interconnected factors, like overlapping circles in a Venn diagram. First, upper basin controls—such as groundwater, snowpack, and runoff—determine how much water is available. Second, biological opinions set flow requirements to protect endangered fish and habitats, including flushing and geomorphic flows.

This is a screenshot showing the hydrology for Lake Earl WA inside the CDFW climate hydrology explorer web tool.

Lettuce field in the Salinas River Valley. California’s Salinas Valley is one of the most productive agricultural basins in the world due to the fertile valley soil, temperate climate, and availability of water for irrigation.

Artichoke field in the Salinas River Valley. California’s Salinas Valley is one of the most productive agricultural basins in the world due to the fertile valley soil, temperate climate, and availability of water for irrigation. 

CAWSC Biogeochemistry group at 2025 IEP Workshop. Left to Right: Back Row - Maura Uebner, Keith Bouma-Gregson, Kyle Leathers; Middle Row - Crystal Sturgeon, Zoё Siman-Tov, Lane Bratz, Emily Richardson, Tamara Kraus, Alex Ryan; Front Row - Nick Framsted 

CAWSC poster presenters at 2025 IEP Workshop. Clockwise from upper left: Anna Conlen, Elise Shea, Lex Thomas, Zoё Siman-Tov, Bryan Gopez, Emma Walker, David Hart, Maura Uebner, Lawrence Fujiwara, Trevor Violette.

Santa Ana Sucker (Pantosteus santaanae) being measured in PIT tag study done in the late summer and early fall of 2024.

Example of Santa Ana Sucker (Pantosteus santaanae) lure with a PIT tag attached.

The photo shows members of the research team. From left to right: Tevin Bui (RCD), Jordan Buxton (USGS), Brett Mills (RCD), Alicia Ruan (RCD), and Brock Huntsman (USGS). Inset at right are Marissa Wulff (top) and Jeff Gronemyer (bottom), both of the USGS. 

The above photos show raceways at the Riverside Corona Resource Conservation District (RCD) facility.

This photo shows a passive integrated transponder (PIT) tag reader being used to test a tagged Santa Ana Sucker.

The photo shows (left) the raft outfitted with the PIT tag reader and two cameras, both facing down into the river. And (right) a PIT tag attached to a lure.

Active (or moving) camera footage of Santa Ana Sucker (Pantosteus santaanae). Cameras were attached to “selfie sticks” and walked up and down the raceways (or fabricated streams).

An open-source image recognition program was used to detect the fish and lures in the videos. The program was “trained” to recognize the fish and lures by exposing it to approximately 800 images of fish and non-fish.

Footage of Santa Ana Sucker (Pantosteus santaanae) from passive (or stationary) camera. Part of a USGS study on the effectiveness and safety of the PIT tagging sampling method.

This is a screenshot of the web tool: Legacy Mercury Contamination from Historical Gold Mining.

View of San Francisco from the USGS research vessel. The goal of this study was to identify the reasons for discrepancies between fChl measurements made under different sampling conditions.