Images

Amelia Ayers, a Physical Scientist with the U.S. Geological Survey, packs up the equipment used to gather shellfish samples collected at Martinez Harbor, Contra Costa County, California. The shellfish trap and composite samplers are attached to a rope with a heavy weight and deployed in the water. It is retrieved once or twice a month depending on the season.

Amelia Ayers, Zoë Siman‑Tov, of the USGS and Lexi Yokomizo of Restore the Delta arrive at Martinez Harbor in Contra Costa County, California to sample shellfish and test them for toxins found in Harmful Algal Blooms (HABs).

Scientists with the U.S. Geological Survey and Restore the Delta gather shellfish samples collected at Martinez Harbor, Contra Costa County. The shrimp are tested for levels of toxins found in Harmful Algal Blooms (HABs). P. macrodactylus shrimp is an invasive shrimp found in the region and commonly caught in the USGS traps.

A drone view of where scientists with the U.S. Geological Survey gathered shellfish samples collected at Martinez Harbor, Contra Costa County.

A drone view of where scientists with the U.S. Geological Survey and Restore the Delta gathered shellfish samples collected at Martinez Harbor, Contra Costa County. The shrimp are tested for levels of toxins found in Harmful Algal Blooms (HABs).

Zoë Siman-Tov (left), a Hydrologic Technician with the U.S. Geological Survey, and Amelia Ayers (center), a Physical Scientist with USGS, gather and measure shellfish samples collected at Martinez Harbor, Contra Costa County. The shellfish trap is baited and deployed for two days in the water before being retrieved.

Scientists with the U.S. Geological Survey and Restore the Delta gather shellfish samples collected at Martinez Harbor, Contra Costa County. The shrimp are tested for levels of toxins found in Harmful Algal Blooms (HABs).

Scientists with the U.S. Geological Survey and Restore the Delta gather shellfish samples collected at Martinez Harbor, Contra Costa County. The shrimp are tested for levels of toxins found in Harmful Algal Blooms (HABs).

Scientists with the U.S. Geological Survey and Restore the Delta measure shellfish samples collected at Martinez Harbor, Contra Costa County. All shellfish are collected, species identified, and individuals measured with calipers. These specimens will all be sent to a laboratory to test their tissue for toxins caused by Harmful Algal Blooms.

Scientists with the U.S. Geological Survey and Restore the Delta measure shellfish samples collected at Martinez Harbor, Contra Costa County. All shellfish are collected, species identified, and individuals measured with calipers. The shrimp are then tested for levels of toxins found in Harmful Algal Blooms (HABs).

Zoë Siman-Tov (left) and Amelia Ayers, both with the U.S. Geological Survey, analyze shellfish samples collected at Martinez Harbor, Contra Costa County, CA. Shellfish (shrimp, crab, or crayfish) caught in the traps are analyzed for toxins found in Harmful Algal Blooms (HABs). 

This picture shows the Mojave River in southern California during a high flow stage.

Shows all dams removed having been removed. Removal of the four hydroelectric dams is the first crucial step to restore the health of the Klamath River and the communities that depend upon it. Work now continues to restore the 2,200 acres of formerly submerged lands. Restoration crews will be onsite until vegetation success meets predetermined performance metrics.

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.

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. 

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.

Aerial shot of bird migration. The kōlea, or Pacific Golden-Plover (Pluvialis fulva), is a familiar bird in Hawaiʻi that migrates to Alaska each summer to nest. 

Conference area of Cal Poly San Luis Obispo Field Office. The Tech Park II office space offers various amenities including conference rooms, break areas, and convenient access to campus resources, fostering an environment conducive to collaboration with the university.