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Program Element
     Name of study: MALLARD SLOUGH PUMPING PLANT MONITORING PROJECT

     Program manager
          Name:    James  Orsi 
          Agency:  California Division of Fish and Game
          Address: 4001 N. Wilson Way
                   Stockton, Ca. 95204

          Phone:  (209) 942 6087 ( TDD  only).
                  For most information contact W. Lee Mecum
                  (209) 942 6088.

Purpose/Objective:  
     This program is a pilot program to develop a method for
     monitoring for the presence of fish vulnerable to entrainment
     within the intake channel of the Mallard Slough Pumping Plant.
     This monitoring will provide information which will enable the
     Contra Costa Water District to minimize the impacts to local
     fish populations when diverting water from the Delta.

Geographic range of field work:
     The Contra Costa Water Districts Mallard Slough Intake Channel
     and Suisun Bay (Sacramento River) in the immediate vicinity of
     the channel mouth.

Number of sites:
     There are two sites.  One in the Mallard Slough Intake Channel
     itself and one in Suisun Bay just outside the entrance to the
     intake channel (RKI = RSAC075).

Period of record (Start year):  1995.

Size for complete data base for program element in KB (MB): 
     Less than 1 megabyte at present.  The total length is not
     expected to exceed 2 megabytes.

Number of individual files: 1

Sample frequency per time unit (second, week, month):
     Sampling is conducted only when the pumps are in operation. 
     Sampling is bi-monthly from January through May and monthly in
     other months.

     The egg and larval net sampling covers the period between   
     February 15, 1995 through July 15, 1995.  The tow net covers the
     period thereafter.


General category of data collected:
     Water depth, temperature (deg C), secchi disc reading and
     fish abundance.

Field Sampling

Gear type or field instrument used:
     Two types of net were used; an egg and larval net and a tow
     net designed to be mounted on an egg and larval net frame.
     Sampling for the early larval stages of delta smelt and other
     species will be accomplished by using a plankton (egg and
     larvae) net.  Both nets were mounted on an egg and
     larval net frame with a flow meter in the center of the mouth.
     The egg and larval net had a mesh size of 0.505.  The tow net 
     was made of bobinet with approximately 3 holes per cm.  It had
     a  fyke  about 71 cm from the mouth.  The code end was a  bobinet 
     cylinder held open by 30 cm diameter metal rings.  A zipper at
     the end permitted the bag to be opened to remove the catch.

     Tows were made alternately in the channel and the river.  The
     tows in the channel were made from the cyclone fence  that
     crosses the channel (approx 30 m from the pumping plant) to
     within 15 to 30 meters of the mouth.  The tows in the bay
     were made against the current from a point chosen so as to
     cross in front of the entrance about midway through the tow
     about 20 to 25 m off shore.

Egg and Larval Net Sampling: 
     The egg and larval net was alternately towed in the intake  
     channel and in river.  The samples were preserved in a 1-quart jar
     in 5% buffered formalin solution.  The preserved samples were be
     taken to the  DFG  Bay-Delta Division laboratory in Stockton for
     processing.
     
Tow net sampling:
     A tow net designed to fit an egg and larval net frame was used
     on August 10, 1995 only.  It was towed alternately in the   
     channel and the bay.  Fish caught in this net were identified and
     measured in the field then returned to the bay.  Specimens that
     could not be identified in the field were preserved and taken
     to the DFG laboratory in Stockton for processing.

Changes in gear or procedures which affected the data over time:
     None so far.

Laboratory analysis - Chemical
     None performed.

Laboratory analysis - Biological
     Name and address of laboratory(s) running analysis:
     All biological analysis was performed by Bay-Delta laboratory
     staff at the Ca. Dept of Fish and Game office in Stockton
     (4001 N. Wilson Way, Stockton, Ca. 95205).

Current since (date):
     Beginning of the project (March 1995).

Methodology for each analysis:
     Each sample is spread in a square tray.  All fish are
     identified and enumerated.

     The total number of fish per cubic meter of water sampled
     was calculated using the following equation:

          F = C / (A * MF * MR) * 100
          Where: F = the number of fish per 100 cubic meters
                 C = the number of fish counted
                 MF = the meter factor for calculating the number
                      of meters per revolution
                 MR = the number of net meter revolutions

Current procedure since (date):
     Beginning of the project (March 1995).

Reference used for identification of organisms:
     Wang, Johnson: Fishes of the Sacramento-San Joaquin estuary
     and adjacent waters of California, a guide to the early life
     history.  Interagency Ecological Study Program technical report
     9.  1986.

Location of reference collection:
     California department of Fish And Game Bay-Delta Division   
     Stockton, California, 95205.