Gathering and measuring shellfish samples collected at Martinez Harbor, Contra Costa County, California

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. The shrimp are tested for levels of toxins found in Harmful Algal Blooms (HABs).