Monitoring juvenile Chinook salmon outmigration using rotary screw traps on Deer and Mill creeks

The California Department of Fish and Wildlife (CDFW) conducts juvenile salmonid emigration monitoring on Mill and Deer Creek (Tehama County, CA) annually from October through June using rotary screw traps (RSTs). Data from this monitoring is used to estimate juvenile spring-run Chinook salmon (Oncorhynchus tshawytscha) (spring-run) abundance and passage, identify yearling outmigration timing and alert resource agencies of juvenile spring-run presence in the lower Sacramento-San Joaquin Delta. This data will be included in the development of a juvenile production estimate (JPE) for spring-run Chinook salmon in the Sacramento River as required by Condition of Approval 7.5.2 of Incidental Take Permit No. 2081-2019-006-00 (ITP) issued by CDFW to California Department of Water Resources (DWR) for the long-term operation of the State Water Project. Salmonid data collected from the Mill and Deer RSTs, among other datasets, is also used by the Salmon Monitoring Team (SaMT) to understand the movement of juvenile salmon in the Sacramento River Watershed to estimate the number of winter-run and spring-run Chinook salmon that have entered the Sacramento-San Joaquin Delta (Delta). SaMT is a real-time operations monitoring team required by Condition of Approval 8.1.2 of the ITP which meets weekly from October through June, to provide advice for real-time management of SWP operations to DWR, CDFW, and the Water Operation Management Team (WOMT) to minimize take of winter-run and spring-run Chinook salmon in the Delta.