Description: The Enhanced Delta Smelt Monitoring (EDSM) program is a comprehensive, year-round monitoring initiative that employs multiple research crews conducting concurrent trawling operations across designated strata within the San Francisco Estuary. The program specifically targets post-larval Delta Smelt from April through June using 20mm trawling gear, while Kodiak trawling gear is utilized for the remainder of the year. Need: The ongoing decline of the Delta Smelt population has underscored the critical need for continuous improvement in the data supporting our understanding of the ecological and anthropogenic factors influencing Delta Smelt population dynamics. The EDSM program plays a vital role in providing essential biological data that informs management strategies aimed at mitigating the adverse effects of water operations on this endangered species. By capturing data across nearly all life stages of Delta Smelt, including near-real-time information on juvenile and adult stages, the EDSM program offers significant conservation benefits. This data is promptly disseminated to the Smelt Working Group and other resource managers to facilitate informed decision-making during the critical entrainment season. Objectives: -Estimate the total abundance of Delta Smelt, including standard errors or confidence intervals, on a weekly to bi-weekly basis across various life stages (post-larvae, juveniles, sub-adults, adults) throughout the year. -Assess the spatial distribution of Delta Smelt at a management-relevant temporal and spatial resolution. -Provide data that supports management decisions and addresses scientific inquiries related to sampling efficiency, drivers of Delta Smelt population patterns, and other conservation and management-related topics.
The Environmental Monitoring Program (EMP) began in 1975 to conduct baseline and compliance monitoring of water quality, phytoplankton, zooplankton, and benthic invertebrates in the San Francisco Bay-Delta estuary. This monitoring program was designed to track the impact of water diversions to the State Water Project (SWP) and Central Valley Project (CVP) on the Bay-Delta. In the decades since, EMP scientists have monitored these constituents at fixed and floating stations throughout the estuary and ensured compliance with state and federal mandates such as Water Right Decision 1641 (D-1641). In the years and decades since its inception, EMP has become one of the cornerstones for scientists' and managers' understanding of the pace and pattern of change in this critical ecosystem. By sampling water quality and biological communities concurrently, EMP has created a dataset that is uniquely useful in better understanding causal connections between physical, biological, and biogeochemical processes.
The Environmental Monitoring Program (EMP) has conducted the Zooplankton Study since 1972 to better assess trends in the lower trophic food web in the San Francisco Bay-Delta estuary. The study also detects and monitors zooplankton recently introduced to the estuary and determines their effects on native species. Under the auspices of the Interagency Ecological Program for the San Francisco Estuary and mandated by Water Right Decision D-1641, the EMP Zooplankton Study is part of the Environmental Monitoring Program and is conducted by the California Department of Fish and Game (CDFW), California Department of Water Resources (DWR), and the United States Bureau of Reclamation (USBR).
The Delta Juvenile Fish Monitoring Program (DJFMP) has monitored natural-origin and hatchery-origin juvenile Chinook Salmon (Oncorhynchus tshawytscha) and other fish species within the San Francisco Estuary (SFE) since 1976 using a combination of midwater trawls and beach seines. Since 2000, three trawl sites and at least 58 beach seine sites have been sampled weekly or biweekly within the SFE and lower Sacramento and San Joaquin Rivers. The main objectives of the DJFMP are: 1. Document the long-term abundance and distribution of juvenile Chinook Salmon in the Delta. 2. Comprehensively monitor throughout the year to document the presence of all races of juvenile Chinook Salmon. 3. Intensively monitor juvenile Chinook salmon during the fall and winter months for use in managing water project operations (Delta Cross Channel gates and water export levels) on a real-time basis. 4. Document the abundance and distribution of Steelhead. 5. Document the abundance and distribution of non-salmonid species.
The Wetland Regional Monitoring Program (WRMP) Fish and Fish Habitat Monitoring project is a collaborative effort to track biological responses to tidal wetland restoration in the San Francisco Estuary. Monthly sampling is conducted across a network of benchmark, reference, and project restoration sites in the South Bay and North Bay, with the goal of evaluating how wetland restoration influences fish assemblages, habitat use, and ecological condition.
The study uses primarily otter trawls to monitor fish and macroinvertebrate communities. Standardized field methods align with those used in long-term monitoring programs to ensure comparability and data integration across regions. Environmental data, including water temperature, salinity, and dissolved oxygen, are collected in tandem with biological sampling to assess habitat quality and seasonal dynamics.
The program addresses WRMP Guiding Question #4: How do policies, programs, and projects to protect and restore tidal marshes affect the distribution, abundance, and health of fish and wildlife? The data support adaptive management, regulatory compliance, and science-based restoration planning by identifying key habitats, tracking restoration performance, and detecting regional patterns in species composition and abundance over time.
