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

California Department of Water Resources (DWR) currently operates
multiple eight-foot rotary screw traps (RSTs) in both the Low Flow
Channel (LFC) and High Flow Channel (HFC) of the upper 21.5 river
miles of the Lower Feather River. The LFC extends from the Fish
Barrier Dam at river mile (RM) 67.2 to the Thermalito Outlet (RM
59). The HFC extends from the Thermalito Outlet to the confluence
with the Sacramento River. This survey has been ongoing since 1997
with the objective of documenting general salmonid emigration
attributes, such as timing, abundance and composition of salmon and
investigating the influence of environmental factors thought to
initiate emigration, such as flow, turbidity and water temperature.
Data from this monitoring will also be 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）目前在下费瑟河上游21.5河英里河段的低流量河道（Low Flow Channel, LFC）与高流量河道（High Flow Channel, HFC）内，运营多台8英尺旋转螺旋式诱捕器（rotary screw traps, RSTs）。低流量河道的范围为河英里（river mile, RM）67.2处的鱼类拦河坝至特马里托出水口（RM 59）；高流量河道则自特马里托出水口延伸至与萨克拉门托河的汇流处。该监测项目自1997年起持续开展，其目标为记录鲑形目鱼类降海洄游的一般性特征，包括洄游时序、种群丰度与群落组成，并探究被认为可触发洄游行为的环境因子（如流量、浊度与水温）的影响效应。本次监测获取的数据还将用于支撑萨克拉门托河流域春季洄游奇努克鲑的幼鱼种群产量估算（juvenile production estimate, JPE）工作，以满足加州鱼类与野生动物部（California Department of Fish and Wildlife, CDFW）向DWR签发的第2081-2019-006-00号附带捕捞许可的相关要求，该许可用于州水利工程（State Water Project）的长期运营。本年度监测季内的相关数据暂定为临时数据。