Monitoring juvenile Chinook salmon outmigration using rotary screw traps on Yuba River

California Department of Water Resources (DWR) currently operates
multiple eight-foot rotary screw traps (RSTs) at Hallwood Boulevard
RM 7.5. RST operations were conducted by CDFW and then under the
direction of the Yuba River Management Team from 1999 to 2009 at the
Hallwood Boulevard site; and resumed in 2022 by DWR. The Hallwood
site will essentially sample all areas of the lower Yuba River
upstream of Hallwood Boulevard. Additionally, the Hallwood site is
located downstream of the bulk of adult Chinook salmon spawning
areas and downstream of all known spring-run Chinook salmon
spawning. Data are currently being used to inform the development of
a juvenile production estimate (JPE) for spring-run Chinook salmon
in the Sacramento River Watershed as required by Incidental Take
Permit No. 2081-2019-006-00 issued by CA Department of Fish and
Wildlife (CDFW) to DWR for the long-term operation of the State
Water Project. Data within the current year’s monitoring season are
considered provisional.

加利福尼亚州水资源部（California Department of Water Resources, DWR）目前在霍尔伍德大道7.5英里里程标处运行多台8英尺旋转螺旋诱捕装置（rotary screw traps, RSTs）。1999年至2009年间，该霍尔伍德大道点位的旋转螺旋诱捕装置作业由加州鱼类与野生动物部（California Department of Fish and Wildlife, CDFW）牵头，后由尤巴河管理团队统筹实施；2022年该作业由加利福尼亚州水资源部恢复开展。霍尔伍德点位的采样范围基本覆盖霍尔伍德大道上游的下尤巴河所有区域。此外，该点位位于绝大多数成年奇努克鲑鱼产卵场的下游，同时也处于所有已知春季洄游奇努克鲑鱼产卵场的下游。当前，这些数据正用于支撑萨克拉门托河流域春季洄游奇努克鲑鱼幼鱼种群产量估算（juvenile production estimate, JPE）的研发工作，以满足加州鱼类与野生动物部（CDFW）为加利福尼亚州水资源部开展州水利工程长期运营所签发的第2081-2019-006-00号附带捕捞许可的相关要求。本年度监测季内的监测数据暂视为暂定数据。