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Metadata Requirements for IEP Files for Delta Agricultural Diversion Evaluation.

Program Element: Delta Agricultural Diversion Evaluation.

Purpose: Develop reliable estimates of fish losses to various agricultural diversions relative to the abundance of those species and life stages in adjacent Delta channels.

Geographic range of field work: Central and southern Delta.

Number of sites (stations): Approximately 3-5 sites each year, locations may vary.

Period of record: 1992 - 4 sites; 1993 - 5 sites; 1994 - 3 sites; 1995 - 3 sites.

Sample frequency per time unit: Egg & Larval - Usually starting in April and ending the first week of July. Sampling intervals are 5 to 60 minutes, Monday through Thursday, 2 samples per day is the average. Juvenile & Adult Fish - Usually starting in April and ending in October. Sampling intervals are 1 to 21 hours, Monday through Thursday, 1 to 6 samples per day are taken.

General category of data collected:
Egg & Larval:
Start and end time of sampling (Pacific standard time);
Surface specific conductance (uS/cm);
Temperature (degrees Fahrenheit);
Diverted water (meters cubed & acre feet);
Flow (cubic feet per second);
Screen (none, on, off);
Net end (mesh box, wooden box, other);
Number of Eggs (American shad, Striped bass-(morula, early, late, dead), all other species);
Number of Larvae (Species codes).
Comments (sampling conditions, explanations).
Juvenile & Adult Fish: Start and end time of sampling (Pacific standard time);
Surface specific conductance (uS/cm);
Temperature (degrees Fahrenheit);
Diverted water (acre feet);
Flow (cubic feet per second);
Screen (none, on, off);
Net end (mesh box, wooden box, other);
Number of Larvae (Species codes).
Comments (sampling conditions, explanations, etc.).

Gear type or field instruments used:
Egg & Larval:

Diversion: Plankton net on a PVC frame, 8 feet long made of 505-micron mesh Nitex netting. In 1992 a .5 meter net was used and in 1993 and 1994 a 1'x1' meter net was used. A 32-ounce plastic collecting jar with a screened 470-micron mesh bolting cloth is attached to the end of the net. Thermometer, EC meter, and digital flow meter.
Channel: Egg and larval sled.

Juvenile & Adult Fish :
Diversion: Fyke nets made of 1/8-inch Delta-type mesh, one net is 24 feet long and secured directly over the outfall pipe with a wooden live-box attached at the end, and the other net is 16 feet long with wings set at the head of the concrete ditch with a mesh live-box attached at the end. Electrofishing, EC meter, thermometer, and pint sized plastic jars for collection of water samples (1992-1994) and flow meter on siphon pipe. Channel: Townet and trawls (midwater, otter).

Brief description of field sampling procedure:

Egg & Larval:

Diversion: Samples collected in the irrigation ditch by 5 to 60 minute egg and larval net sets with collecting jar attached to the end of the net. At the end of the set samples were rinsed into a collecting jar and preserved in 5 percent formalin and rose bengal dye was added to the eggs and larvae to increase visibility. A contracted consultant performed egg and larval laboratory identification work.

Channel: Samples collected by a single 10-minute oblique tow with an egg and larval net mounted on a towing frame with skis. Samples methods are essentially identical to those used by fish and Game in its Delta-wide egg and larval sampling program. At the end of the set samples were rinsed into a collecting jar and preserved in 5 percent formalin and rose bengal dye was added to the eggs and larvae to increase visibility. A consultant performed egg and larval laboratory identification work. Mutilated larvae representing more than 50 percent of total body length were counted as whole larvae.

Juvenile & Adult Fish: Diversion: Samples collected at the diversion outfall by 1 to 21 hour fyke net sets with either a wooden or mesh live-box attached to the end of the net. All fish caught were identified, enumerated and measured to the nearest millimeter total length. If field identification was not possible then the fish were sent to the contracted consultant for laboratory identification. Mutilated larvae representing more than 50 percent of total body length were counted as whole fish.

Channel: The sampling methods used are those used by the Department of Fish & Game in its Delta townet survey work. Samples collected by two tows, one with current and one against current made with either a townet or trawl (midwater or otter) every 60 minutes.

Reference to written protocols: Study plans for 1993, 1994 & 1995; Temporary Barriers Project Fishery, Water Quality, and Vegetation Monitoring Reports for 1993, 1994 & 1995 - contact program manager.

Changes in gear and/or procedures over time: *Modification of nets from 1992 to 1993: Egg & larval .5m net to egg & larval 1'x1' net; having all juvenile nets as winged seine nets to having some enclosed seine nets.

*Procedure changes from 1992 to 1993: Juvenile sampling changed from placing the nets in the diversion ditch and sampling a percentage of the diversion flow to placing the nets around the outfall pipe and at the head of the diversion ditch to sample 100 percent of the flow. Measuring the first 25 species to measuring the first 20 species for both egg & larval, and juvenile & adult fish.

*Procedure change from 1992 to 1993: Sampling at Twitchell Island changed from the 14" siphon downstream of light 35 opposite Fishermans Cut, to the 16" siphon at Oulton Point.

Laboratory analysis - Chemical No chemical analysis are done for the Delta Agricultural Diversion Evaluation.

Laboratory analysis - Biological
Name and address of laboratory running analysis: Johnson Wang, PHD; National Environmental Services, Inc.; 1758 Concord Ave.; Concord, CA 94520 From 1992 to 1998.

Current procedure since: 1992 Historical procedures or reference to other documentation: N/A

*Methodology for each analysis: Egg & larval samples are rinsed with water through a No. 50 sieve (300 - micron mesh), sorted under a magnifying illuminator, all eggs and larvae are removed and counted. Eggs and larvae are identified to species or the lowest taxonomic level known; striped bass eggs are classified as dead, morula, early or late embryo. Mutilated larvae representing more than 50 percent of total body length are counted as whole fish. The first 20 individuals of each species are measured to the nearest millimeter, total length.

*Processing is subject to strict quality control program: The first 10 samples that a sorter completes will be resorted by the quality control supervisor. An accuracy rate of 90 percent will be maintained. After successful completion of the first 10 samples, one sample will be chosen at random for rework. If the 90 percent accuracy rate will be maintained, the 10 percent rework mode continues. If a sample fails the Q.C. check, all of the following samples will be reworked until 10 consecutive samples pass, whereupon the sorter will return to the 1 in 10 mode.

Current procedure since: 1992 Historical procedures or reference to other documentation: N/A

Reference used for identification of organisms: Larval fish reference collection of more than 125 species collected by Dr. Wang in 1978 through 1992; Wang (1986 and 1990, 2 editions); revision of Wang (1981).

Location of reference collection: Department of Water Resources; 3251 S Street; Sacramento, CA 95816, and contract lab indicated above.