Chinook salmon (oncorhynchus tshawytscha) and steelhead trout (oncorhynchus mykiss) rely on seasonal tributaries from which they were not born (non-natal) for critical rearing habitat

The U.S. Fish and Wildlife Service (USFWS) awarded a Cooperative Agreement valued at $182,625 to the Pacific States Marine Fisheries Commission (PSMFC) under the Central Valley Project Improvement Act (CVPIA, CFDA 15.648) on August 1, 2025, with a completion date of May 19, 2028. This award funds Phase Two of the Sacramento River Tributaries Non-Natal Rearing Evaluation Project, which expands upon foundational work initiated in 2022. The project delivers multi-year, pre-restoration monitoring and evaluation services focused on seasonal tributaries connected to the upper mainstem Sacramento River that provide critical rearing habitat for Chinook salmon and steelhead trout during juvenile life stages.

The primary deliverables under this award include comprehensive field monitoring data on flow regimes, temperature conditions, and juvenile fish presence across selected seasonal tributaries in the Sacramento River Basin. Through this scientific research and monitoring effort, PSMFC will identify high-priority non-natal rearing habitats and generate findings to inform future restoration actions, including habitat reconnection initiatives that align with CVPIA restoration priorities. The project ultimately supports evidence-based decision-making to enhance habitat connectivity and improve population resilience for anadromous fish species in the Sacramento River Basin.

Building on the foundational work of maslin ET AL. (1999), the USFWS and the pacific states marine fisheries commission (psmfc) launched phase one of the sacramento river tributaries non-natal rearing evaluation project in 2022. This second phase expands that effort through multi-year, pre-restoration monitoring of seasonal tributaries connected to the upper mainstem sacramento river. These tributaries, though seasonally disconnected, offer valuable refuge and foraging habitat during key juvenile life stages. This project will evaluate flow regimes, temperature conditions, and juvenile fish presence across selected streams. The goal is to identify high-priority non-natal rearing habitats and inform future restoration actions, including reconnection efforts identified as a cvpia priority restoration action. Findings from this work will support science-based decisions to enhance habitat connectivity and improve resilience for chinook salmon and steelhead populations in the sacramento river basin.