Shasta and Scott River Salmonid Outmigrant Monitoring FY23/24

One rotary screw trap (RST) was operated on the Shasta River from end of January to the end of June in 2023 and end of January to mid-June in 2024. Another rotary screw trap was operated on the Scott River from mid-February to mid-July in 2023. In 2024, one rotary screw trap was operated on the Scott River from mid-February to mid-June. The RSTs was used to sample all age classes of emigrating Chinook Salmon (Oncorhynchus tshawytscha), Coho Salmon (Oncorhynchus kisutch), and steelhead trout (Oncorhynchus mykiss).

In 2005, Coho Salmon of the Southern Oregon/Northern California Coast Evolutionary Significant Unit were listed as a threatened species from the Oregon border to Punta Gorda, California under the California Endangered Species Act. The data collected from the RSTs on both the Scott and Shasta River represent one of the only long-term monitoring datasets for Coho Salmon populations and other target species, which can be used to evaluate the effectiveness of restoration projects that are intended to increase juvenile salmonid production and survival. Drought conditions over the last three years have resulted in critically dry and emergency situations for local salmon that require an expanded juvenile monitoring effort. Monitoring juvenile coho and their summer habitat will expand our baseline habitat use information, help inform Voluntary Drought Initiative agreements, and support any required law enforcement effort.