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Name of study: Feather River Fish Studies

PROGRAM ELEMENT                                   

Name: Feather River Fish Studies

Program Manager:
     Ted Sommer/Debbie McEwan
     California Department of Water Resources
     3251 S Street
     Sacramento CA  95816
     (916) 227-7537/(916) 227-7624

Purpose/Objective: 

     In cooperation with DFG, DWR has initiated a number of
studies on the lower Feather River.  Many of the study components
are included in a recent draft Central Valley Improvement Act
(CVPIA) plan to restore anadromous fish in the system.  The
present study will examine the timing and magnitude of
outmigration of Feather River fish species relative to different
physical conditions.  Specific goals of the study include:

     1)  Examine species composition of outmigrants with emphasis
     on target species:  Chinook salmon, steelhead, Pacific
     lamprey, American shad, splittail and green sturgeon.

     2)  Identify general salmon emigration attributes such as
     timing, abundance, life stage composition, condition, and
     investigate the influence of the factors initiating
     downstream migration such as flow turbidity, and water
     temperature.

     3)  Develop an annual juvenile salmon production index, by
     associating spawning intensity with emigration data.

     4)  Integrate emigration data into "real-time" monitoring
     program in the Delta for fisheries management.

     5)  Optional:  Mark (with coded wire tags) in-channel
     produced Feather River fish for comparison with the
     distribution and survival of hatchery fish.  (Note that a 5-
     year hatchery evaluation program is being conducted
     concurrently.  Up to 1 million young salmon/year are to be
     marked in the hatchery study).

Geographic range of field work:   Lower Feather River from Live
Oak upstream to Feather River fish hatchery.

Number of sites: Two traps

          1. Thermalito outlet (FR060N)
          2. Live Oak (FR042E)

Period of Record (Start year): March 1995 - present

Size for complete data base for program element in KB:  (Update
weekly)

Number of individual files:  During the sampling season the file
will be updated weekly on a "near time" basis.  The final product
for each year will be one or more files.  

Sample frequency per time unit:  

     One or more observations at each trap each day.

General category of data collected:

     Biological:    Fish species (Character)
                    Fork length (mm)
                    Count (Integer)
     Physical:      Temperature (degrees F)
                    Secchi Depth (m)    
                    Weather (NIT,FOG,RAN,CLD,CLR)
     Gear Status:   Condition (1-4)       
                    Gear Status(0-3)
                    RPM (Revolutions)
                    Total Revolutions (Integer)
                    Water Velocity (fps)
                         
Comments about element:

     This is not an IEP funded study, however the data have been
included because it is directly relevant to fisheries monitoring
in the Sacramento-San Joaquin system.  In an effort to make the
data as compatible as possible with existing IEP programs, we use
the same data sheets and codes as the Real Time Monitoring
program.  Automatic error checking in the data entry program uses
many of the same criteria that FWS Stockton uses for beach seine,
screw trap and midwater trawl monitoring.

Field Sampling

     Field collection of data is performed by DWR Environmental
Services staff based at Oroville Field Division.  Eight foot
diameter screw traps (EG Solutions, Oregon) have been placed in
two sites in the lower Feather River.  Separate traps were needed
because the two river reaches are managed differently, so
outmigration cues and species composition may be distinct.  

     The traps will be fished daily for six months (January-June)
each year of the 4-year evaluation.  Additional months may also
be considered to collect data on several fish species. Traps will
be serviced at least one a day in the morning and more often in
periods of peak emigration.  Trapped fish will be removed from
the livebox, sorted by species, counted, then measured to the
nearest 0.5 mm for up to 50 of each species.  Other data will
also be collected at each trap:  secchi depth, water temperature
and effort.  

     Trap efficiency will be measured using mark-recapture methods. 
Young salmon are to be fin clipped (dorsal or caudal) and held in
live boxes adjacent to the traps.  The target minimum number for
each study is 1,000.  Salmon will be kept for 1-5 days before
being released approximately 1 km upstream of each trap.  Gear
comparisons may also be performed using fyke nets.

Data Analysis

     Data analysis is performed by staff under the direction of
the Project Manager.  Lotus Approach (Release 3.02)is used for
data entry and has automatic error checking or pull-down menus in
all fields. The output from this process is in dBASE format.  All
files are inspected for outliers.

     Using the raw data, species composition comparisons will be
made:  1)  between the upper and lower reach; 2) to similar
systems in the Central Valley; and 3) to available life history
data.  We will also evaluate annual differences in spawning
timing and success, juvenile survival and production relative to
different physical variables (ie secchi depth, flow and
temperature).  The following annual production estimates will be
developed:  

     1)  Total abundance indices

          Total number of fish or yearling equivalents based on
          catch data and trap efficiency results  
     
     2)  Escapement-corrected indices 
          
          Index = emigration/adult escapement,
               where escapement is from DFG Region 2
      
     3)  Emigration indices corrected for spawning intensity

          Index = Emigration/spawning area
               where spawning area is developed from aerial
               photography during spawning surveys in the
               preceding autumn of each year.