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Delta Smelt Early Warning Studies: Application of the SmeltCam to Describe Processes Influencing Delta Smelt Distribution and Movements

Locations of fixed water quality stations and corresponding fish sampling sites in the San Joaquin River at Jersey Point and in False River.

Locations of fixed water quality stations and corresponding fish sampling sites in the San Joaquin River at Jersey Point and in False River.

The primary goal of this research is to identify the mechanistic processes driving sub-adult Delta Smelt distribution and movements before and during upstream dispersal and migration, in particular when Delta Smelt are vulnerable to water project entrainment. The general approach will pair, for the first time, non-lethal fish sampling via the SmeltCam (Feyrer et al. 2013) with comprehensive measurements of the physical and biological environment. The results of this research will provide new insights into the variation in the vertical and lateral distribution of Delta Smelt in the water column, associations of Delta Smelt distribution with physical and biological habitat features, and relatively short time scale processes driving Delta Smelt behavior and movements. Additionally, the study may collect data on juvenile salmonid distribution and movements through the San Joaquin River corridor, providing valuable information that could be applied towards management of water project operations.

Objectives are to

  1. Estimate the vertical and lateral distribution of Delta Smelt and WRCS in the water column in relation to physical and biological habitat features before and during upstream migration.
  2. Estimate a standardized spatial distribution of Delta Smelt and WRCS with respect to tidal stage along the San Joaquin River corridor.
  3. Advance the application and development of the SmeltCam through (a) improved species identification, (b) calibration of observations, and (c) assessment of indirect mortality.

Additionally, this project is supportive of U.S. Geological Survey (USGS) programs and goals in California. This project offers the opportunity to further develop collaborative efforts within USGS for evaluating the habitats occupied by special status fish species and how they are affected by water project operations. These data will be important for informing operational plans and habitat restoration efforts in California. Thus, the project will increase the visibility of the Center and individual researchers as experts in the fields of ecology and habitat restoration for special status fish species in California.

This proposal also supports several elements of the USGS strategic plan. The project will contribute to multiple missions of the USGS: 1) describe and understand the Earth; 2) manage water and biological resources; and 3) enhance and protect our quality of life. The project will help strategically position the USGS as the provider of choice for assessments of real and anticipated changes in the environment and resources. More specifically, the project will showcase the unique capabilities of the USGS to further our understanding of environmental change.