Description Suisun Bay and Marsh are a key part of the habitat for Delta Smelt, but during drier periods such as summer, Delta Smelt may be at least partially excluded from Suisun Marsh due to high salinities. The purpose of this proposal is to provide scientific support a management action for Smelt, operation of the Suisun Marsh Salinity Control Gates (SMSCG). This facility is currently to tidally pump water into the Marsh to improve fall and winter habitat conditions for waterfowl, but could also provide a tool to manage aquatic habitat for Delta Smelt in other periods. Specifically, by using the SMSCG to direct more fresh water in Suisun Marsh, our prediction is that reduced salinities will improve habitat conditions for Delta Smelt in the region. Need The status of Delta Smelt is dire. As part of the Resources Agency's Delta Smelt Resiliency Strategy, in August 2018 we conducted pilot operations of the SMSCG to support Delta Smelt , with promising results. Based on this early success, we expect that the SMSCG will be used as a seasonal tool to support Delta Smelt in summer-fall in coming years as part of the coming FWS Biological Opinion and DFW ITP. Neither has been completed, but SMSCG operations for fish are expected to be required in each. Hence, the proposed study is intended to provide a scientific evaluation and guidance for an expected SMSCG action in 2020. Objectives The primary objective of this project is to evaluate the effectiveness of the SMSCG action. Questions to be addressed include: Did the action improve habitat conditions for Delta Smelt in the Suisun Region? Does the Suisun Region typically have better habitat and food web conditions than the upstream River Region? Do Delta Smelt respond favorably to the SMSCG flow action? Does operation of the SMSCG affect other fishes and clams?
Description The purpose of this study is to expand IEP monitoring and inference to other dominant near-shore, littoral habitats not sampled by beach seines through the use of boat electrofishing. To accomplish this we will sample key littoral fish species across various near-shore habitats in order to determine how best to estimate abundance, occupancy, capture probabilities, and related environmental drivers. Need Expanding DJFMP sampling to other habitats throughout the Delta will allow our program to detect and monitor fishes and ecological trends through time, alleviating a recognized data gap. Current sampling relies on data collected through non-random fixed point sampling of unobstructed habitats, which limits the utility of our data to inform management decision. Objectives • Design boat electrofishing survey methods to expand DJFMP’s monitoring into habitats and locations not sampled by beach seining. • Design and develop field and data analysis methods for estimating capture probability and abundance using boat electrofishing techniques. • Predict spatio-temporal distribution of habitats occupied by key littoral species.
To support management planning in Suisun Marsh, this project is developing a body of science and tools to understand past, present, and potential future changes to the Marsh’s ecological patterns, processes, and functions. This project builds on SFEI’s prior work in the Delta, extending historical ecology mapping, landscape change studies, and the Landscape Scenario Planning Tool to cover Suisun's historical and present-day landscapes. Through spatially explicit representations of the historical function and condition of the marsh and analyses of landscape metrics, this project is evaluating changes over time in landscape support for ecosystem functions and services in Suisun. In order to incorporate diverse perspectives into planning resources, project activities include engagement with local tribes and community members to understand community interests, priorities, and uses of the Marsh. Findings will be shared through a report and article for both technical and general audiences, and spatial analyses and data layers will be made available through the Landscape Scenario Planning Tool.
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.
