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Georgiana Slough Acoustic Barrier Test, 1994

Program Manager:
Darryl Hayes
California Department of Water Resources
3251 S Street, Sacramento CA 95816
(916) 227-7546

The purpose of this project is to determine the effectiveness and 
feasibility of utilizing acoustic barriers to guide out-migrating 
salmon down the Sacramento River.

Geographic range of field work:
The barrier was installed at the confluence of the Sacramento River
and Georgiana Slough: 380 14' 20" N, 1210 31' 0" W

Number of sites:
The barrier consisted of 21 speakers spaced at 30 foot intervals and 
was anchored at the upstream edge of the Sacramento River and Georgiana 
Slough confluence.  Two main sampling locations were utilized in the 
study: one downstream of the confluence in the Sacramento River and one
downstream of the confluence in Georgiana Slough.  A third infrequently 
used station was in the Sacramento River upstream of the barrier.

Period of record:
This database covers the 1994 study

Size for complete data base for program element in KB (MB):
This data base consists of one file and is 475 KB.  The first five columns 
of the database are of the format required in the IEP Data Files.  

Sample frequency per time unit:
This project strived to take 10 minute samples 24 hours a day using 1 
Kodiak trawling team.  One set consists of six trawls:  Three trawls 
were be performed in the Sacramento River (one on the left, one in the 
middle and one on the right), then the boats would move to Georgiana 
Slough and perform three trawls in the center (the slough was too narrow 
to perform bank trawls).  The trawls were performed Monday through 
Thursday from 4/5/94 through 6/4/94 (the permit did not allow for 
trawling Friday through Sundae).  During the testing period the barrier 
was cycled on and off  at set intervals.  This permitted data to be 
collected which could be used to determine the barriers effectiveness.

General category of data collected:
The type of data collected were the number of fish caught, number of 
fish per volume of water sampled and the number of fish per minute of 
trawling.  The latter two types of data are termed Catch Per Unit 
Effort (CPUE).   In addition, the stage height, temperature, and flows 
through Georgiana Slough, the Delta Cross Channel and the Sacramento 
River were recorded.  Barrier operation was noted in the data sheets.

Gear type or field instrument used:
The type of gear used was Kodiak trawl

Brief description of field sampling procedure:
Two boats were used in performing the Kodiak trawls, the net boat and 
the tow boat.  The net boat was operated by three people and would 
initiate the trawl by backing upstream as the Kodiak trawl was laid 
out into the water. Once accomplished, the boat operator would spin 
the boat around and take up the tension on the tow lines.  The crew 
then pass one tow line to the tow boat.  The boats  separate and tow 
the net at a set RPM for ten minutes.  At the end of the trawl the
flow through the net was calculated from a flow meter which was placed 
in the water when the tow began and removed when the boats came together.
The tow boat would pass back the line to the net boat, which would then 
spin around to face downstream as the crew pulled in the net.  The live 
box was brought aboard and the fish placed in a holding tank.  The net 
would be re-set in the manner described above.  During the next trawl 
the crew of the net boat anaesthetized the fish with carbon dioxide,
identified and measured the fish.  The boat operator recorded the data,
along with the flow meter readings and the temperature.  Any processed 
fish from a previous trawl would be passed to the tow boat, which 
released the fish downstream and out of the study area.