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.
This project aims to test the feasibility of using novel acoustic transmitters to track Delta smelt in the San Francisco Bay-Delta. Successful utilization of acoustic telemetry to track Delta smelt can provide researchers and resource managers with information about the species’ habitat preferences, the effects of water-management practices on Delta smelt movement and distribution, and the success of ongoing supplemental release efforts. The assessment of feasibility will include a comprehensive analysis of both the lethal and sublethal effects of surgical tag implantation on Delta smelt, as well as the development of a species-specific tagging protocol.
Due to pervasive anthropogenic influences (e.g., habitat alteration, climate change), current rates of biodiversity loss in the Sacramento-San Joaquin Delta are unprecedented. Application of appropriate management regimes and mitigation measures thus require effective biological monitoring to adaptively manage systems. Non-invasive environmental DNA (eDNA)-based tools for endangered species monitoring have gained attention as a complementary approach to traditional sampling because of their increased sensitivity and accurate quantification. However, the unique characteristics of environmental RNA (eRNA) make it a novel tool, allowing us to gain additional information that is not possible to obtain with eDNA. Using novel eRNA tools to improve detection and quantify health status of Smelt has only been theorized and remains to be empirically tested. Both Delta and Longfin Smelt species were historically ubiquitous in the Sacramento-San Joaquin Delta, but have declined precipitously over the past several decades. One source of mortality is entrainment into the south Delta water export pumps. Although the entrainment of juvenile and adult smelt has been regularly monitored at fish salvage facilities, entrainment of larval smelt (< 20 mm) is not quantified, thus remains largely unknown. Moreover, given the current climate change effect (e.g., increased heat stress), an understanding of how these endangered species will respond to acute stress response in the wild is lacking.
SacPAS serves to provide information integration services to the Central Valley Project Improvement Act and practitioners working on matters related to ESA-listed fishes. The web-based services relate fish passage to environmental conditions and provide resources for evaluating the effects of river management and environmental conditions on salmon passage and survival.
The work performed as part of this agreement includes developing, maintaining, and making accessible query tools and decision support tools to access: historical, real-time and forecasted data; data summaries and visualizations; and hindcasts, forecasts, and scenario-derived predictions from statistical and mechanistic models. More specifically, the objectives are to:
1) Maintain and extend a secondary data repository of historical, real-time, and forecasted fish, environmental, and operational data from the Sacramento River and other river systems in the Central Valley, integrated from primary, public databases.
2) Maintain and improve the data query and visualization tools and services provided through the SacPAS website (https://www.cbr.washington.edu/sacramento/) for historical, real-time, and forecasted environmental and fish data.
3) Conduct research and provide access to modeling tools for fish survival and migration, through the SacPAS website, in support of Reclamation-funded and ESA-mandated activities, especially in efforts to predict, track, and evaluate the efficacy of proposed or actual actions.
