2 (020

Fish Collections and Secondary Louver Efficiency

at the Tracy Fish Collection Facility:

October 1993 to September 

MARK D. BOWEN' , SCOTT M. SIEGFRIED2, CHARLES R. LISTON'

LLOYD J. HESS., AND CATHERINE A. 

TRACY FISH COLLECTION FACILITY STUDIES,

CALIFORNIA, VOLUME 7

UNITED STATES DEPARTMENT OF THE INTERIOR

BUREAU OF RECLAMATION

DENVER TECHNICAL SERVICES CENTER

Ecological Research and Investigations Group

AND

MID-P ACIFIC 

. 2South Central California Area Office

Tracy Office

May 1998

TABLE OF CONTENTS

Pa2e

ABSTRACT. . . 

BACKGROUND AND FACILITY 

THE SECONDARY LOUVER SIEVE NET 

METHODS. . . . 

Data Collection. . . . 

Statistical Methods. . . . 

RESULTS. . . . 

Sieve Net and Holding 

Length Frequencies. . . 

Sieve Net and Holding 

DISCUSSION. . . . . . 

RECOMMENDATIONS...................................................... 

Long Term

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

Short 

SUMMARY AND CONCLUSIONS

ACKNOWLEDGMENTS. . . . 

LITERATURE CITED. . 

TABLES

Table 1. . . . . . . . . . . . . . 17

Table 2. 

Table 3. . . . . . . . . . . . 20

Table 4. (Oncorhynchus

tshawytscha) runs observed at Red Bluff Diversion Dam . . . . . . . . . . . . . . . . . . 21
TABLE OF CONTENTS (continued)

Page

FIGURES

Figure 1. Map of the Sacramento - San Joaquin Delta indicating the location of

the Tracy Fish Collection Facility. . . . . 

Figure 2. Schematic of the Tracy Fish Collection Facility . . . . . . . . . . . . . . . . . . . . . . . . . 23

Figure 3. 

(b) chinook salmon taken in the holding tank (n=595) and sieve net

(n=94), and (c) chinook salmon taken during the day (n=482) and at

night (n=169) . . . . . . . . . 

Figure 4. 

Figure 5. 

Figure 6. Length frequency histograms for (a) all American shad (n=248),

(b) American shad taken in the holding tank (n=104) and 

net (144), and (c) American shad taken during the day (n=199)

and at night (n=49) " . . 

Figure 7. Length frequency histogram for all white catfish 

Figure 8. Secondary louver efficiency at the Tracy Fish Collection Facility at three

times of day for (a) all species combined, (b) chinook salmon, and

(c) splittail 

Figure 9. Secondary louver efficiency at the Tracy Fish Collection Facility at three

times of day for (a) striped bass, (b) American shad, and (c) white catfish . . . 30

Figure 10. Secondary louver 

at the Tracy Fish Collection Facility for (a) all 

(b) chinook salmon, and (c) splittail ...................................

Figure 11. Secondary louver 

at the Tracy Fish Collection Facility for (a) striped bass, (b) American

shad, and (c) white 

Figure 12. Secondary louver 

Facility for (a) all species combined, (b) chinook salmon, and (c) splittail 
TABLE OF CONTENTS (continued)

Pa/le

Figure 13. Secondary louver 

Facility for (a) striped bass, (b) American shad, and (c) white catfish . . . . . . . 34

APPENDIX A - MAJOR SPECIES 

INFORMATION. . . . 

Chinook Salmon

. . . . . . . . . 

Delta Smelt. . . . 

Splittail '" 

Striped Bass. . . . 

American Shad

. . . . . . . . . 

White Catfish. . . . 

White and Green Sturgeon. . . . 

APPENDIX B - REVIEW OF TRACY FISH COLLECTION FACILITY STUDIES:

Volumes 1-4 ........................................................... 39
Fish Collections and Secondary Louver Efficiency

at the Tracy 

October 1993 to September 1995

ABSTRACT

The of this study were 

(1) describe the 

through the secondary louvers and into the

holding tanks at the Tracy Fish Collection

Facility (TFCF) and (2) 

louver 

environmental and 

We deployed a sieve net in the 

channel behind the second louver array and

collected 254 

holding tank samples between October 1993

and September 

goal we 

composition and size of fish passing through

the secondary 

numeric dominant in the sieve net and holding

tank 

(79 percent) were made in 1995 , a wet year.

Therefore we 

dominance was the result of a strong spawn

and entrainment of many young-of-year fish

(Mean TL = 31 rnm (1.2 in) J to the TFCF. 

second goal was to analyze secondary louver

efficiency. We 

efficiency as the percentage of fish directed

into the holding tanks compared to the number

of fish entering the secondary 

concentrated our analysis of secondary louver

efficiency on three 

secondary approach velocity index, debris

load, and time of 

approach velocity 

appeared to have any statistically significant

influence on secondary 

However, the time of day had a 

significant impact on 

efficiency in two cases. First, for all species

combined, logistic regression 

time of day was efficiency 

Efficiency = 81 percent, Night = 67 percent ).

Second, for , the time of

day was negatively correlated with efficiency

(Daylight Mean = , Night =

83 percent). We concluded that future research

should continue to focus on time of day as a

factor influencing secondary louver efficiency.

In addition, we 

improve fisheries protection at the TFCF. For

example, in the high water year of 1995 , we

obtained 99.9 percent of 371 splittail

between May 

contracted period of vulnerability, approach

velocity could be 

secondary louver channel to improve splittail

louver efficiency while we continue to meet

all water and fish agreement obligations.

BACKGROUND AND FACILITY

DESCRIPTION

Since 1873 , the U.S. Government has assisted

the State of California in water development

in the Central Valley (U.S. Congress, 1874).

Subsequently, Bennett' s (1906) report for the

S. Reclamation Service (now U.S. Bureau

of Reclamation 

number of possible 

development of the Sacramento River basin.

Cooperative investigations by 

and the State Engineer s Office resulted in a

comprehensive plan for water development in

the Central Valley (Anonymous, 1931). This
Tracy Fish Collection Facility Study

plan 

Project (CVP); a key 

transfer of water from the Sacramento River

basin to the San Joaquin watershed. In 1933

the CVP was approved by State referendum.

In 1935 , the U.S. Congress authorized the

CVP 

Reclamation began construction.

The 

water from the Sacramento River 

system from the north and the San Joaquin

drainage system from the 

systems converge in the central portion of the

state forming a huge natural estuary and Delta

(Figure 

San Francisco Bay-Delta are influenced by

many factors including tides, precipitation

freshwater outflows, export 

irrigation practices. 

irrigation have influenced the Delta ecosystem

for decades.

Two important components of the CVP are a

pumping plant in the southern portion of the

Delta (Tracy 

canal to move the water to the southern end of

the Central Valley (Delta 

(DMC)). These two components are central to

the export of water for irri ation domestic

and industrial needs. Now, the TPP is one of

two large pumping plants in the south Delta

(the other is the State-operated 

Banks Delta Pumping Plant). The TPP draws

water from the Old River channel of the lower

San Joaquin River into the intake channel of

the DMC. Before the Old River water enters

the DMC, the water passes through the TFCF

(Figure 2). The TFCF is a large fish diversion

and salvage facility that operates to prevent

fish from being drawn into the Delta Mendota

Canal intake 

facilities are located about 

northwest of 

intake channel, and a pilot 

structure (site of the 

completed in 1951. In 1952, Reclamation and

the U.S. Fish and Wildlife 

assistance from the California Department of

Fish and Game and the California Department

of Water Resources, began testing various

types of 

Department of the Interior, 1957) at the pilot

structure to reduce impacts of pumping on

striped bass (Morone saxatilis) and chinook

salmon (Oncorhynchus tshawytscha). After

2 years of testing, it was 

system of louvers, bypasses and

collectionlholding tanks was 

diverting fish from the debris-laden flow of

the south 

completed in 1955 , and by 1957, the current

fish facility was in 

decade, primary and secondary louvers, louver

guides, trashrack, valves, other supporting

infrastructure, and 

pumps were 

Collection Facility.

The fish diversion system at the TFCF uses a

louver-bypass-collection system to divert fish

from exported flow 

sections are a framework of evenly 

(23.4-rnm (O.92-in) openings) vertical slats

that traverse the channel and allow water to

pass to the pumps while creating turbulence

which the fish can detect. Design of the louver

system was based on observations that fish

orient upstream, into the flow, but when they

encounter an obstruction, move laterally to be
Tracy Fish Collection Facility Study

swept downstream (Bates and Visonhaler

1956). Thus, the fish guide along the louver

face and eventually are carried into a bypass

opening. The probability that a fish will be

louvered (or guided into a bypass opening) is

strongly influenced by its swimming ability,

size, and the approach velocity (EPR!, 1986).

We define approach velocity as the average

velocity parallel to the rectangular 

upstream of 

independent factors than approach velocity

may influence louvering; these 

amount of debris blocking the louver spaces

bypass velocities, predator load, and time of

day among other variables.

Two louver systems screen fish at the TFCF.

The first or primary louver system is 97.5 m

(320 ft) in length and 

25.6-m (84-ft) wide 

openings each 15.2 cm (6 in) in width (one

occun1ng about every 22.9 m (75 ft)) lead into

91.4-cm (36-in) diameter pipes that 

water and fish to the secondary louver system.

The 

parallel lines of louvers (each 9.3 m (30.2 ft)

long) that span the 2.4-m (8. ft) wide

secondary channel also at a 

and material diverted by this system enter a

common bypass opening which feeds into four

large circular holding tanks (flows are directed

into only one tank at anyone 

second 

concentrate the collected fish and reduce the

volume of water entering the holding tanks.

Fish, and debris, are regularly removed from

the holding tanks and returned to the Delta.

The 

surface trash 

concentrates and directs floating debris to a

conveyor belt for disposal, and by a trashrack

with 9-mm (2.1-in)

intervals. The trashrack is located between the

surface trash deflector and the primary louver

array. Together, the deflector and trash rack

function to keep large debris from entering

and damaging the primary louver system. The

trashrack also prevents 

entering the facility. The trashrack and louvers

become heavily clogged with river 

(primarily macrophytes) at various 

throughout the 

trashrack and louvers are cleaned frequently,

often daily, because debris accumulation may

negatively affect fish salvage efficiency.

The louver system at the TFCF was designed

to divert and collect young (~ 25-rnm (I-in)

total 

downstream migrating chinook salmon smolts

from the exported flow (Bates and Visonhaler

1956). During the first few years of operation

pumping was mostly restricted to the summer

months, a time when young salmon were less

vulnerable to entrainment by the pumps. This

period of peak pumping coincided with the

presence oflarge numbers oflarval and postlarval striped bass. However, Bates and

Visonhaler postulated that the louver-bypass

system diverted most of these fish.

The current practice of year-round pumping at

high rates (and consequently higher velocities)

was s with

construction of San 

consequence of 

relatively high rates is that the louver system

may 

originally designed. Under current operating

procedures, discharges (Q) through the facility

range from 0 to 141.5 /s (0 to 4 500 ff/s) in

the primary channel and from 0 to 3.
Tracy Fish Collection Facility Study

(0 to 175 ft3/S) in the secondary channel

depending primarily on the number of pumps

operated. In addition to the pumps, flow

hydraulics and fish entrainment to the TFCF

are influenced by the 

water diversions and tides.

The objectives of this investigation 

describe the populations of fish observed in

the holding tanks and passing through the

secondary 

re-evaluation of secondary louver efficiency

(defined as the success of the secondaries at

diverting fish into the holding tanks) under

current operating 

conditions include higher discharges, greater

channel approach velocities, and higher debris

accumulations than in previous decades. This

evaluation focuses on fish species of special

concern or economic importance including

green (Acipenser medirostris) and white

(Acipenser sturgeon

American shad (Alosa sapidissima), splittail

(Pogonichthys macrolepidotus), white catfish

(Ictalurus catus), delta smelt (Hypomesus

transpacificus), chinook salmon, and striped

bass.

THE SECONDARY LOUVER

SIEVE NET 

In the 1950' , the 

efficiency was 92 to 100 percent for chinook

salmon and 86 to 95 percent for striped bass

(Bates et aI., 1960). In 1966- , efficiency in

the primary louvers was 75 to 100 percent for

striped bass of 

1967). From 1991 to 1992, the range oflouver

efficiencies for chinook salmon was 72 to

100 percent in the secondaries. And, louver

efficiencies for striped bass 

96 

90 percent in the secondaries (Karp et aI.

1995.

We hypothesized that louver efficiencies have

deteriorated at the TFCF. We investigated this

hypothesis in the 

deploying a sieve net behind the second of the

two secondary louver 

principal objectives. First, we studied the fish

population passing through the secondary

louvers at the TFCF. Second, we 

secondary louver efficiency with respect to

environmental and operational parameters.

In this report, we evaluate the fish passing

through the secondary louvers, determine

critical , and

estimate sample sizes required for these future

trials. 

elucidate our understanding of the 

influences on salvage efficiency.

METHODS

Data Collection

We collected 254 

October 27, 1993 , and September 20, 1995.

Each paired sample consisted of a sieve net

sample and a holding tank sample obtained

simultaneously. The sieve net is 

12.8 m 

secondary louver array and completely spans

the secondary channel. The sieve net (mouth:

244 em 

6 m 3 mm 

deployed for the same length of time fish are

directed into a holding tank (effective mesh
Tracy Fish Collection Facility Study

size: 3.2 mm (118 in)). From both the sieve net

and , all 

identified to species and the number recorded.

When possible, we measured individuals to

the nearest mm in fork length (FL).

We found the secondary louvers/holding tank

system and 

salmon in the same size 

However, we felt it possible that other species

and life 

different effectiveness because the louvers and

sieve net are fundamentally different types of

gear. Both of these methodologies capture

individuals as small as 20 mm (0.8 in) FL. We

believe both gears to be most effective for fish

greater than 30 mm (1.2 in) FL; therefore, we

limited comparisons between the two methods

to fish greater than 30 rnm (1.2 in) FL.

Environmental and 

recorded in association with each paired (sieve

net/holding tank) sample: water temperature;

depth in front of the trashrack and in the

primary and secondary channels; wet weight

of debris in the sieve net and holding tank;

ambient light conditions (day, dusk, night, and

dawn); secondary bypass opening (0 to 600

and 

Occasionally, we recorded whether 

water was on or off 

combination ofVC pumps in operation.

We used 

channel water depth and facility parameters to

calculate primary discharge and 

discharge. In addition, we used primary and

secondary depths, and the number of operating

VC pumps to provide the secondary approach

velocity index (SA VI).

Statistical 

We defined 

tank fish catch/(holding tank fish catch + sieve

net fish catch)). We analyzed the dependent

variable salvage efficiency through a four-step

process.

First, we coded three 

for the analysis. Debris load was coded "

when less than 150 grams (0.33 lb) of debris

was obtained in the holding tank

, 

2" when the

amount of 

(0.33 to 0.771b) grams, and "3" when more

than 350 grams (O.77Ib) were observed. Time

of day was coded "0" for night

, 

1" for

crepuscular (dawn and dusk) periods, and "

for day. SA VI 

intermediate velocity indices and intermediate

and "2" for high. 

and SA VI were selected by expert opinion.

These 

information concerning the TFCF exists with

which to improve them.

Second, we conducted a 3-Way Analysis of

Variance (ANOV A) with 

independent variables and raw efficiency. If

all assumptions of 

(normality, homogeneity of variance, and

independence of observations), we analyzed

and reported the ANOV A table.

Third, if an , we

performed two 

efficiency 

transformed the data so that we might meet

the assumption of normality. Then, we could

still use the robust ANOV technique. We

then conducted a 3-Way ANOV A with each

transformed data set. If all 
Tracy Fish Collection Facility Study

ANOV A were met, we analyzed and reported

the ANOV A table.

Fourth, if an assumption was violated with the

transformed data, we coded the raw efficiency

as "0" when salvage efficiency was less than

75 and as " 1" when efficiency was greater

than 0.75. We 

regression. All 

performed with Statistical Analysis Software

Version 6. 11 (SAS Institute Inc. , c;ary, NC).

RESULTS

Sieve Net

Collections

and Holding Tank

In 254 paired samples, we collected a total of

065 fish 

sieve net and a 408 

representing 33 species in the holding tanks.

In both, the sieve net and holding tanks, the

numeric dominant was splittail (Table 1). For

all species combined, sieve net and holding

tank catch rates (fish/minute) were greater

during light hours than during dark 

(Table 2). However, 201 of 254 

samples were obtained during 

crepuscular periods. Furthermore, during the

period when catch rates tend to increase at the

TFCF (March through June), we 

94 daytime and crepuscular samples and only

20 samples , the large daytime

catch rate we 

have been 

daytime and crepuscular sampling. In addition

to catch rate, louver 

statistically lower at night for 

combined (Table 3). We also examined the

paired sample collections for 

regarding the target species such as chinook

salmon.

The fall run of 

abundant of the four , we

expected the number of smolts observed at the

TFCF to peak in May each year (see Table 4

and Appendix A). During May, the sieve net

and holding tank retained chinook salmon

smolts at 1.75 to 6 times the rate of 

months of the year. For example in the sieve

net, chinook salmon smolts were obtained at

0.161 fish/minute in all months except May,

when the catch rate was 0.282 fish/minute. In

sieve net and , we

observed catch rate for chinook salmon taken

during light hours was 

during dark hours (Table 2). However, like

the daytime 

combined, daytime chinook salmon 

rates could have been inflated due to when we

did our most intensive sampling. The inflation

of catch rate as an artifact of our 

regime, could explain why our results differ

from that of Puckett et al. (1996). They found

catch 

generally higher at night. In this study with

regard to chinook salmon, the catch rate at the

TFCF peaked in May and was slightly higher

during light hours; the mean louver efficiency

was 83 percent (Table 3). For chinook salmon

we obtained sufficient 

samples) to analyze seasonal and die! trends

and secondary louver efficiency. But, this was

not the case for delta smelt.

We caught only two delta smelt during this

study. Both were within 

expected adult 

vulnerable to 
Tracy Fish Collection Facility Study

smelt was caught on February 2, 1995 , and

another on April 12, 1995. These dates are

within the period we 

seeking spawning habitat (see Appendix A).

In , splittail 

routinely observed in the sieve net and holding

tank paired samples. Splittail abundance may

have been high, compared to other years, for

two , we 

254 paired samples in 1995. Second, 1995

was a wet 

spawn 371 splittail

collected in this study, 99. 9 percent of these

fish were obtained between 

July 13 suggesting 

susceptible to entrainment to the TFCF when

the young-of-the-year appear in the 

However, the nighttime catch rate is unknown

because of limited 

Another interesting result was the mean catch

rate in the sieve net 9 splittail per

minute while. the 

species combined was 1. 6 fish per minute.

Mean splittail catch rate was higher than that

for all species combined because we discarded

0:0 paired samples from this analysis , i. , if

we caught no fish in the 

holding tank, we did not use 

sample in the calculation of catch rate because

this observation provided 

regarding catch rate. In this study with regard

to splittail, the catch rate was six times greater

than that for all other species from May 

July , the mean 

efficiency was 63 percent (Table 3).

Unlike splittail, striped bass were taken yearround, the slowest catch 369 fish/

minute) 

compared to 

(1.657 fish/minute). This period includes the

typical spawning period (Moyle, 1976). We

theorize that striped bass eggs and larvae are

too small for our gear during 

April 6 to June 20, and the previous year

progeny 

susceptible to entrainment. In holding tank

samples, striped bass exhibited a 

higher catch rate during light periods than

during dark periods. Yet, in the sieve net, the

catch rates during light and dark periods were

nearly indistinguishable (Table 2). The mean

louver 

86 percent (Table 3).

Like , American shad show

seasonal periodicity in 

susceptibility. From May 

American shad young are moving downstream

to the ocean and are most 

entrainment. In the sieve net and holding tank

combined, we found the catch rate, between

May I to , to be 0. 533 fish/

minute in 

year: 0. 007 fish/minute. American shad also

showed a significant diel trend; they are two

or more times as likely to pass through the

louvers and into the sieve net during the light

hours than during dark hours (Table 2). Mean

salvage efficiency was 52 percent. And, the

salvage efficiency at night was significantly

higher than during the day (Table 4).

White catfish showed little seasonality in the

sieve net and holding tank collections. This

species was detected year-round. White catfish

catch rate in the holding tanks and sieve net

was higher 

(Table 2). Overall, white catfish mean louver

efficiency was 89 percent.
Tracy Fish Collection Facility Study

In contrast to the white catfish's ubiquity, no

sturgeon were taken during this 

paired 

79.4 hours of the 16 632 hours that transpired

during the course of this 

sturgeons' rareness in the salvage at the

TFCF, their capture was an extremely unlikely

event in the study s brief sampling period.

Length Frequencies

We found 96 

measured in this study were between 70 and

130 mm (2. 8 and 5.2 in) FL (Figure 3a). As

expected, chinook salmon at 

vulnerable to entrainment to the TFCF. Few

salmon 30 to 70 mm (1. 2 to 2. 8 in) FL were

collected. Both the holding tank and sieve net

mesh sizes are small enough to capture these

smaller fish. 

smaller size range have traveled down river a

sufficient distance to 

entrainment.

Length 

collected in the holding tank and the sieve net

are similar (Figure 3b). However, smaller

smolts 

(Figure 3c).

A few splittaillengths were recorded 

this study (n=74). Of these 74 observations

young of the year (Mean FL = 31 mm (1.2 in))

dominated the catch (Figure 4).

The average FL of striped bass 

this study was 116 mm (4.6 in). The largest

individual collected was 366 mm (14.4 in) FL

(Figure 5).

The distribution of American shad lengths is

bell-shaped (Figure 6a) and centered at a mean

of96 mm (3. 8 in) FL. When these data were

partitioned by gear type, we observed slightly

larger fish in the holding tank than in the sieve

net (Figure 6b). When partitioned by time of

day, these data indicated slightly larger fish

were collected during dark hours compared to

light hours (Figure 6c).

The distribution of white catfish lengths was

bimodal suggesting we often collect the first

two year classes (Figure 7). In this study, we

collected fish from 33 to 

14.0 in) FL. This result suggests white catfish

may be vulnerable to 

TFCF their entire lives.

Sieve Net 

Statistical 

Tank

When an individual representing a fish species

was caught in the 

paired holding tank sample, we defined this as

an 

Conversely, when we obtained a species in the

holding tank but not in the paired sieve net

sample, we defmed this as a salvage efficiency

of 

occurred. Therefore, we found the secondary

efficiency data were distributed bimodally. No

transformation 

distribution. Therefore, we relied upon logistic

regression, a non-parametric 

(Hosmer and Lemeshow, 1989).

We observed only two 

effects for louver 

Interestingly, they both involved time of day:
Tracy Fish Collection Facility Study

positive 

combined and a 

American 

graphically to determine if diel 

exist that were not 

(Figures 8-9). However, it appeared variation

in the data would mask any real differences

that might exist.

F or the 

(SA VI) , no 

relationships to salvage efficiency emerged.

The 

efficiency, with regard to the SA VI, reflects

our inability to account for many sources of

error in operational parameter measurement

(Figures 10- 11). 

exhibits a great deal of variability with regard

to debris load (Figure 12-13). Our measure of

debris 

unmeasured operational parameters than was

the 

However, the variation in efficiency with

regard to debris was considerable.

Three factors interact to make this 

less robust than desired. First, the required

non-parametric analysis, logistic regression

may not be as effective at determining real

differences as a parametric technique would

be. Second, there is a great deal of variability in 

efficiency. Third, operating conditions were

not always reported with these samples , e.

screen water. Thus, additional sources of

variation may be 

biologically significant effects. We concluded

that the most conservative interpretation of

these data is they do not represent a sample of

sufficient size to demonstrate statistically that

time of , or 

approach velocity are influencing secondary

louver efficiency.

DISCUSSION

In the first assessment of the TFCF, Bates et

al. (1960) reported chinook salmon secondary

salvage efficiency was 92 to 

Karp et al. 

72 to 100 

secondary louver efficiency was 83 percent for

chinook 

efficiency may be lower for chinook salmon

now than when the facility was constructed.

For striped bass. Bates et al. (1960) reported

the secondary salvage efficiency was 88 to

97 percent. Hallock (1967) reported striped

bass louver efficiencies in the primaries were

75 to 100 percent. Karp et al. (1995) reported

louver efficiency for striped bass was 40 to 96

percent in the primaries and 44 to 90 percent

in the secondaries. We found secondary louver

efficiency was 86 

overall facility efficiency for striped bass

could be 82 percent (.96 x .857). Like chinook

salmon, overall TFCF salvage efficiency for

striped bass may now be lower than at the

time of construction.

Examination of the sieve net and holding tank

collections suggested that time of day was

related to catch rate for all species combined

chinook salmon, splittail, American shad, and

white catfish. For every species for which

sufficient data were collected, except striped

bass, time of day 
Tracy Fish Collection Facility Study

rate. In addition, time of day was a statistically

significant influence on salvage efficiency for

all species 

Furthermore, compared , larger

chinook salmon were 

smaller American shad 

night. Thus, subsequent experiments could

focus on the relationship between time of day

and 

experimental approach to the 

between time of day and 

require a 

observations. For such an 

estimated the required sample size.

To , we 

observations of variation in salvage efficiency

to determine the 

Way ANOVA 

independent variables we 

extensive variation (see Table 3, column 3)

observed in the 

suggested a large number of samples would be

required to determine if the independent

variables of interest truly influence salvage

efficiency. We calculated the 

required to discriminate the influence of time

of day, debris, and approach 

secondary louver efficiency. We wanted to

detect a true difference of 10 percent between

means. We accepted a 20 percent chance that

we 

hypothesis and a 5 percent chance that we

might 

determined for 

210 observations would be required for each

unique combination of the three independent

variables (Sokal and Rohlf, 1981). The

estimated sample size (n) of 210 for each

combination should be 

conducted a I-Way ANOV A with two or three

levels oftime of day. In contrast, in this study,

we had 110 chinook salmon samples for three

levels of light.

We suggested that our sample size was not

sufficient to 

significant influence of debris on 

louver efficiency. Yet, debris causes extensive

logistical problems at the TFCF. Each year

floating water-hyacinth Eichhornia

crassipes and Egeria (or Brazilian 

Egeria densa require hundreds of hours for

removal. These two species were not in the

Delta when the TFCF was constructed. These

plants were 

cleaning of the louvers has 

difficult in recent years. In addition to debris

we also investigated the influence of approach

velocity on secondary louver efficiency.

Because secondary velocity was not measured

we developed an index of channel velocity,

SA VI. However, we 

effectively evaluate the influence of channel

velocity on secondary salvage efficiency. Any

additional data 

including a measurement of channel velocity.

While back-calculating the average channel

velocity may be helpful, direct measurements

of secondary channel velocity may be more

important because a complex flow field exists

in the secondary channel.

In this study, we found time of day was related

to 

influence of 

approach velocity was not detected. However

many 

independent 

influence louver 
Tracy Fish Collection Facility Study

anything affecting the amount of light in the

channel could influence what fish sense and

therefore, louver efficiency. Cloudy weather

wind, and water turbidity could all influence

the amount of light in the channel and louver

efficiency. And, the cumulative 

factors unaccounted for by us 

obscured the influences of any of the factors

we , debris load and

approach velocity might have a 

influence on louver efficiency and we did not

detect it because of 

variation.

The life 

coupled to entrainment to the 

example, in the high water year of 1995

99.9 percent of the 18 371 splittail observed in

this study was obtained between May 

July 13. Chinook 

example. In May of each year, we captured

chinook salmon smolts at 2.5 to 3 times the

rate of that during the remainder of the year.

In addition, Puckett et al. (1996) found the

number of 

holding tanks was correlated with time of day

and tides. We postulate that operations of the

TFCF could be better tailored to life history

traits of target species. An 

could determine feasibility of protecting more

fish through four , we would

consider a new 

Tracy system by using real-time monitoring

and adaptive management. Second, we would

make predictions of fish 

TFCF and test , we

could 

decrease impacts on fish while still meeting

water and fish agreement obligations. Fourth

we 

experimental 

determine if we can improve salvage and still

meet our 

agencies.

RECOMMENDATIONS

Long Term

Salvage efficiency at the TFCF may 

declined over the 

changes have occurred in the Delta ecosystem

over this period that could also be responsible

for this decline. 

could be due to the facility itself having aged;

the superior maintenance schedule met at the

TFCF term

exposure to brackish water and the weather.

Furthermore, new 

available in the last 4 decades. Future plans

for the Tracy Fish 

Program (TFFIP) should include experimental

facilities with tests of new technologies and

operational flexibility (Liston 1997).

Experimental designs should test louver and

screen sequences in lab and field settings. The

screen sequence could have an extremely

leaky louver" as the first barrier encountered.

Predominantly, large fish would be louvered

by 

subsequent screens could be less leaky louvers

or positive barriers directing smaller fish to

holding tanks.

Short Term

We 

salvage efficiency data set. The variation in

efficiency obtained in this study was used to
Tracy Fish Collection Facility Study

calculate sample sizes required for a more

robust analysis of the influences on secondary

salvage 

combination of 

210 

collected. We suggest that a 1- 

be undertaken for each independent variable

of interest 

addition, this new data set could be used to

investigate 

louvering efficiency between day, crepuscular

periods, and night. Furthermore, new data

could contribute to our understanding of how

different life stages and 

louvered.

Whenever possible, direct observations of

current velocity should be 

secondary channel. These data should be

obtained simultaneously with paired sieve net

and holding tank samples.

Further 

should be , if the

velocity control pumps at the 

replaced, perhaps "fish friendly" pumps such

as those being tested at Red Bluff (Liston et

aI., 1997) could be employed to improve fish

survival.

SUMMARY AND CONCLUSIONS

We evaluated the influence of time of day,

debris load, and secondary approach velocity

index on secondary salvage efficiency. Time

of day 

commonly 

efficiency. We recommend additional study of

time of day and its 

This study may require a 

efficiency observations to 

Approach velocity has long been recognized

as an 

protection. 

should be directly 

With quality velocity data, we could evaluate

the importance of channel velocity on fish

salvage and 

recommendations for improving fish salvage.

Previous studies and this research indicate that

salvage efficiency may have declined over the

last 40 years. We could optimize the current

facility' s performance and we may not be able

to attain the salvage efficiencies required to

maintain critical fish species in perpetuity. We

recommend a study of real-time monitoring

and adaptive 

salvage scheme 

developed that 

endangered and economically important fishes

while water and fish agreement obligations are

met at the TFCF.

Analysis of new sieve net and holding tank

data taken , and

proposed lab and field 

further refine our 

affecting louver 

experimental facility has been recommended

(Liston, 1997). An important new concept to

test would be a 

screens rather than a single type of barrier. We

postulate that screen criteria for Delta smelt

and chinook salmon might be met with a

sequence of screens operated at one facility.

Results from the experimental facility would

be used to 

present facility, or 

replacement.
Tracy Fish Collection Facility Study

ACKNOWLEDGMENTS

This study was funded by Reclamation s Mid-Pacific Region (Sacramento, CA) and the Denver

Technical Service Center. Partial funding for this study was provided by Reclamation s Research and

Technology Development Program, Study Number AE CO-98.0 16 (W A TR). 

Herb Ng, and the staff in Tracy, CA, for their support during this study. State of California personnel

worked with us on several technical problems and 

(Utah State University) and Johnson Wang (National Environmental Sciences, Inc.) for assistance

with technical issues. Finally, we thank Ron Brockman and Jim LaBounty for program guidance.
Tracy Fish Collection Facility Study

LITERATURE CITED

AFS, 1991. Common and Scientific Names of

Fishes from the United States and Canada.

Fifth Edition. American Fisheries Society,

Bethesda, MD, USA.

Anonymous, 1931. Reports of state water plan

prepared pursuant to Chapter 832, Statutes

of 1929. Sacramento River basin. State of

California, Division of Water 

Bulletin No. 26.

Bates, D.W. and R. Visonhaler. 1956. Use of

louvers for guiding fish. Transactions of

the American Fisheries Society 86: 38-57.

Bates, D. , O. Logan, and E.A. 

1960. Efficiency evaluation, Tracy Fish

Collection Facility, Central Valley Project

California. U.S. Fish and Wildlife Service.

Seattle, W A, USA. 67 pp.

Bell, M. 

engineering requirements and biological

criteria. U.S. Army Corps of Engineers

North , OR

USA. 307 pp.

Bennett, S.G. 

and rights of way granted over public land

in northern California for power purposes.

S. Geological Survey. 

Service. Washington, D. , USA. 52 pp.

Borgeson, D., and G.W. McCammon. 1967.

White catfish Ictalurus catus of the

Sacramento-San Joaquin delta. California

Fish and Game 53: 254-263.

California Department of Water 

and U. S. Bureau of Reclamation. 1994.

Biological Assessment: 

Central Valley Project and 

Project on delta smelt and 

splittail. U.S. Fish and Wildlife 

Sacramento Field Office, Sacramento, CA

USA.

Caywood, M.L. 1973. Contributions to the life

history of Pogonichthys

macrolepidotus (Ayres). M.S. 

California State University. Sacramento

, USA.

Daniels, R.A. and P.B. Moyle. 1983. Life

history of 

Pogonichthys in 

Sacramento-San Joaquin estuary. Fishery

Bulletin: 105- 117.

EPRl, 1986. Assessment of downstream

migrant fish 

hydroelectric application. Electric Power

Research Institute, Report AP-47 1 1. Palo

Alto, CA, USA.

Hallock, R.J. 1967. Efficiency 

primary louver system, Tracy Fish Screen.

1966-67. California 

and Game Marine 

Administrative Report, Number 

Sacramento, CA, USA.

Hiebert, S. 

Facility Studies, California, Volume 

Continuous monitoring of fish eggs and

larvae during 1991 and 1992. U.S. Bureau

of Reclamation. Denver Technical Services

Center, Denver, CO, USA.
Tracy Fish Collection Facility Study

Hosmer, D.W. and 

Applied Logistic Regression. John Wiley

and Sons: New York, NY, USA.

Karp, C. , L. Hess, and C. Liston. 1995.

Tracy Fish 

California, Volume 3: 

louver efficiencies for juvenile 

salmon and striped bass at the Tracy Fish

Collection Facility, Tracy, California, 1993.

S. Bureau of 

Technical Services Center, Denver, CO

USA.

Liston, c., C. McNabb, S. Borthwick

W. Frizell, and S. Atkinson. 

and 

Research Pumping Plant program on the

Sacramento River, CA. Proceedings ofFish

Passage Workshop, Milwaukee, WI, USA

May 6- , 1997.

Liston, C. 1997. 

Fish Facility Program. U.S. Bureau of

Reclamation, Denver 

Center Ecological 

Investigations, Denver, CO, USA.

Liston, C. , C. Karp, L. Hess, and S. Hiebert.

1994. .Tracy 

Studies, California, Volume 1: Summary of

the fish predator removal 

intake , 1991- 1992.

U. S. Bureau 

Technical Services Center, Denver, CO

USA.

Mecum, W.L. 

operations for the federal fish collection

facility at Tracy, 

September 30. California Department of

Fish and Game, Anadromous 

Branch Administrative Report 77-

Sacramento, CA, USA.

Meng, L. 1993. Status report on Sacramento

splittail and longfin 

report submitted to U.S. Fish and Wildlife

Service. 

Sacramento, CA, USA.

Meng, L and P.B. Moyle. 

splittail in the Sacramento-San Joaquin

estuary. Transactions of the 

Fisheries Society, 124: 538-549.

Miller, E.E. 1966. White Catfish. Pp. 430-440

In A. Calhoun, editor, Inland Fisheries

Management, California 

Fish and Game, Sacramento, CA, USA.

Miller, L.W. 1972. White Sturgeon. Pp. 54-

In 1. Skinner, editor, Ecological Studies of

the Sacramento-San 

Report 8. California 

and Game, Sacramento, CA, USA.

Moyle, P.B. 1976. Inland Fishes of California.

University of California Press, Berkeley,

, USA.

Moyle, P. , B. Herbold, D.E. Stevens, and

L.W. Miller. 1992. Life history and status

of San

Joaquin 

American Fisheries Society 121: 67-77.

Pelgen, D.E. 1952. A preliminary analysis of

the catfish fishery of the Sacramento-San

Joaquin Delta. California 

Fish and Game, Inland Fisheries Branch

Administrative Report 52-23.
Tracy Fish Collection Facility Study

Puckett, K. , C. Liston, C.A. 

L. Hess. 

Facility Studies, California, Volume 

Preliminary examination of 

influence fish salvage estimates at the

Tracy Fish Collection Facility, California

1993 

Reclamation. Denver Technical Services

Center, Denver, CO, USA.

Reclamation. 1992. Letter dated 7/17/92 from

USBOR, Mid-Pacific Regional Director to

CFG, Director. Agreement attached: 8 pp.

S. Bureau of Reclamation, Mid-Pacific

Regional Office, Sacramento, CA, USA.

Scott, W.B. and 

Freshwater Fishes of Canada. 

Research Board of Canada. Bulletin 

Ottawa, Canada.

Skinner, J.E. 1962. An historical view of the

fish and wildlife 

Francisco Bay area. California Department

ofFish and Game. Water Projects Branch

Report I.

Sokal, R.R. and F.J. Rohlf. 1981. 

Second Edition. Freeman and 

San Francisco, CA, USA.

S. Congress, House of 

1874. 

commissioners on the 

San Joaquin, Tulare, and 

valleys of the 

Congress. House Executive Document 290.

91 pp.

S. Department of the Interior. 

protection at the Tracy 

S. Bureau of Reclamation, Region 2

Sacramento, CA, USA.

S. Fish and 

Sacramento-San 

Fishes Recovery 

Wildlife Service, Portland, OR, USA.

Vogel, D.A. and K.R. Marine. 1991. Guide to

Upper Sacramento River Chinook Salmon

Life History. CH2M Hill, Redding, CA

USA.

Wang, J.C.S. 1986. Fishes of the SacramentoSan Joaquin estuary and adjacent waters

California: A 

histories. Interagency 

Program for the Sacramento-San Joaquin

Estuary, Technical Report 9.
Tracy Fish Collection Facility Study

Table 1. Species 

collected in the sieve net was 065 while 21 408 were collected in the holding tanks.

Two species of specific interest in this study were not collected: green sturgeon and white

sturgeon. Species list follows order and accepted common names of AFS (1991).

Sieve Net Holding Tank

Species Percent Composition Percent Composition

Pacific Lamprey 036 023

American Shad 14.062 760

Threadfin Shad 14.062 8.263

Goldfish 000 014

Common Carp 1.618 527

Red Shiner 009 000

Golden Shiner 181 504

Sacramento Blackfish 2.485 896

Splittail 56.193 56.702

Sacramento Squawfish 018 037

White Catfish 582 212

Black Bullhead 000 005

Brown Bullhead 000 084

Channel Catfish 0.425 1.116

Wakasagi 000 005

Delta Smelt 009 005

Chinook Salmon 265 760

Mosquitofish 090 089

Inland Silverside 714 757
Tracy Fish Collection Facility Study

Table 1 cont. Species composition of 

fish collected in the sieve net was 11 065 while 21 408 were collected in the holding

tanks.

Sieve Net Holding Tank

Species Percent Composition Percent Composition

Three-spine Stickleback 000 009

Prickly Sculpin 112 027

Pacific Staghom Sculpin 009 009

Striped Bass 283 218

Green Sunfish 009 005

Warmouth 009 037

Bluegill 913 653

Redear Sunfish 009 182

Smallmouth Bass 009 009

Largemouth Bass 262 705

White Crappie 000 005

Black Crappie 877 083

Bigscale Logperch 018 051

Yellowfin Goby 271 617

Chameleon Goby 0.470 631
Table 2. Catch per minute at , day, and dusk samples combined into "Light" and night samples only

in "Dark." "NED" = "Not Enough Data. " Sample size (n) refers to the number of samples that contained target fish. Delta smelt

were not collected in sufficient detail to make any estimates of catch rate. Two species of specific interest were not collected: green

sturgeon and white sturgeon. Species list follows order and accepted common names of AFS (I 99 I).

i--oI1.0

Sieve Net Sieve Net Sieve Net Sieve Net Holding Tank Holding Tank Holding Tank Holding Tank

Species Light Light Dark Dark Light Light Dark Dark

(Fish/Minute) (n) (Fish/Minute) (n) (Fish/Minute) (n) (Fish/Minute) (n)

All

Species 280 176 904 13.272 194 585

American

Shad 035 811 629 242

S P littail 11.158 NED 9.215 NED

White

Catfish 577 103 1.112 151 513

Chinook

Salmon 205 105 322 270

Striped

Bass 249 214 854 125 0.467

-c::

.....

iii'

;::;

-c::

.....

-c::
Table 3. Secondary louver efficiency 

were not collected in sufficient detail to make any estimate of efficiency. Two species of specific interest were not collected:

grecn sturgeon and white sturgeon. Species list follows order and 

Mean Standard Total Raw Log,o of Arcsin of Logistic Species Efficiency Deviation Number Efficiency Efficiency Efficiency Regression

Observations

Day = 80.

All Species 71.1 26. 254 tCrepuscuIar = 79.4"

Night = 67.

Day = 38.

American 51.5 45. Crepuscular = 65.

Shad Night = 83.3e

Splittail 62. 30.

White 88. 24. 208

Catfish

Chinook 83. 31.1 111

Salmon

Striped 85. 27. 174

Bass

...

-c:

... ;:

(ii'

::r

Q..

:::J

-c:

...

fJ)

-c:

Note: Independent velocity index. Columns 5 through 8 represent statistical analyses: an empty cell indicates test assumptions were not met or no

variable was significant. If group means are reported, this indicates statistical significance. Statistically similar groups are indicated

by a common lower case character.

~Crepuscular = Dawn and dusk samples.
Tracy Fish Collection Facility Study

Table 4. Characteristics of Sacramento River chinook salmon 

(Oncorhynchus tshawytscha) runs observed at Red Bluff Diversion Dam (Compiled from Moyle, 1976; Vogel and Marine

1991) .

Run First Spawners Peak of Downstream Downstream

Reach Red Bluff Spawning Migration Migration Peak

(Month) (Month) (Range) (Month)

Spring Mar Sep Nov-May Feb

Fall Jul Nov Jan-Jun May

Late-Fall Oct Feb Apr-Dec Aug

Winter Jan Jun Jul-Mar Oct
Tracy Fish Collection Facility Study

Brentwood

w- 

E. Skinner Delta 

Fish Protective Facility 

Delta Mendota Canal 

Tracy Fish Collection Facility

Tracy

Figure 1. Map of the Sacramento - San Joaquin Delta indicating the location of the Tracy 

Collection Facility.
Tracy Fish Collection Facility Study

Figure 2. 

majority of water s flow.
Tracy Fish Collection Facility Study

i 0.

~ 0.

Cii 0.

'00.

8. 0.

~ 0.

II)

80.

Cii

~ 0.

50.

~0.

't:I

~ 0.

fI)

II)

c3 0.

~0.

50.

~O.

Ilding Tank

Qve 

!ht

Qrk

Figure 3. Length frequency histograms at the Tracy Fish Collection Facility for (a) all chinook

salmon (n=689), (b) chinook salmon taken in the holding tank (n=595) and sieve net

(n=94), and (c) chinook salmon taken during the day (n=482) and at night (n=169).

Crepuscular observations (n=38) of chinook salmon were not included in (c).
Tracy Fish Collection Facility Study

~ 0.

......

0 0.4

&.0.

a..

80 

Fork Length(mm)

Figure 4. 
Tracy Fish Collection Facility Study

"C 0.

m--e .4

(ij 0.

...

'00.

~ 0.

CL 0 

Figure 5. 

(n=132).
Tracy Fish Collection Facility Study

I:: 

Iii

~ 0.4

'50. 2 I

~ 0.

Ci 0.

00.

8.0.

c..

~ 0.

~0.

'E 0.

r:t

40 80 

Fork Length(mm)

!Iding Tank

Qve 

!ht

Qrk

40 

Fork Length(mm)

Figure 6. 

shad (n=248), (b) American shad taken in the holding tank (n=104) and sieve net (144),

and (c) American shad taken during the day (n=199) and at night (n=49).
Tracy Fish Collection Facility Study

~ 0.

.....

0 0.

Co 0.

L..

0 0

Figure 7. 

(n=388).
Tracy Fish Collection Facility Study

Figure 8.

,.., 1.

CI)

0 0.

~ 0.

::;,

...J~ 0.

:5 0.

CI)

,.., 1.

0 0.

~ 0.

...J

~ 0.4

:5 0.

,.., 1.

0 0.

~ 0.

...J~ 0.

:5 0.

Time of Day

Ig t

1 = Crepuscular

2 = Day

Time of Day

Time of Day

Secondary louver efficiency at the Tracy Fish Collection Facility at three times of day for

(a) all species combined, (b) chinook salmon, and (c) splittail.
Tracy Fish Collection Facility Study

:... 1.

00.

~ 0.

::s

~ 0. Ig t

I = Crepuscular

:5 0. 2=Day

CIJ

Time of Day

:... 1.

00.

~ 0.

::s

~ 0.

'tJ I = Crepuscular

80. 2 = Day

CIJ

Time of Day

it 1.

0 0.

ffi

~ 0.

::s

~ 0.

'tJ I = Crepuscular

:5 0. 2 = Day

CIJ

Time of Day

Figure 9. Secondary louver efficiency at the Tracy Fish Collection Facility at three times of day for

(a) striped bass, (b) American shad, and (c) white catfish.
Tracy Fish Collection Facility Study

;:., 1.

0 0.

~ 0.

.3 t

...

':-::1

_

~ 0.4

1 0.

- I

Approach Velocity Index

,., 1.

0 0.

~ 0.

::J

...J~ 0.

5 0.

II)

Approach Velocity Index

;:., 1.

u 0.

~ 0.

::J

...J

~ 0.4

5 0.

II)

8 0 0

8 0

8 e 0 0

s:;( 12 

Approach Velocity Index

Figure 10. Secondary louver efficiency versus Secondary 

description) at the Tracy 

(b) chinook salmon, and (c) splittail.
Tracy Fish Collection Facility Study

,., 1.

.~ 0.

€J I

~ 0.

:::J

.....I ~ 0.

g 0.

Approach Velocity Index

,., 1.

0 0.

~ 0.

.....I

~ 0.4

8 0.

Approach Velocity Index

~ 1.

c: 0

.~ O.

~ 0.

.3 0

2; 0.

Approach Velocity Index

Figure 11. Secondary louver efficiency versus Secondary Approach Velocity Index 

description) at the Tracy Fish Collection Facility for (a) striped bass, (b) American shad

and (c) white catfish.
Tracy Fish Collection Facility Study

:0-. 1.

III

Ii:

::::J

~ 0.4

111

III

5000 10000 15000

Holding Tank Debris (g/10 Min.

:0-. 1. U un--e-

~ 08 . 0 0 w ~~'8 0 ~ 0.

:::I

1\1 0

80.

:0-. 1.

'00.

~ 0.

:::I

~ 0.4

1\1

5 0.

C!D 0 000

crID:) 0 ceP

5000 

Holding Tank Debris (g/10 Min.

15000

5000 

Holding Tank Debris (g/10 Min.

15000

Figure 12. Secondary louver 

(a) all species combined, (b) chinook salmon, and (c) splittaiI.
Tracy Fish Collection Facility Study

,.

f"'"

. ~ 0 .:::;0 0 CI) ~ 0 0 0.

~ 0.

0.4 

g 0.2 P

co:o "7D

5000 

Holding Tank Debris (g/10 Min.

--i

15000

~ 1.

~ 08 . 0

~ 0.

~ 0.

III

50.

CI)

5000 10000 15000

Holding Tank Debris (g/10 Min.

:-. 1.

:~ 0.

~ 0.

~ 0.

50.

CI)

5000 10000 15000

Holding Tank Debris (g/10 Min.

Figure 13. Secondary louver efficiency versus debris load at the Tracy Fish Collection Facility for

(a) striped bass, (b) American shad, and (c) white catfish.
Tracy Fish Collection Facility Study

APPENDIX A

MAJOR SPECIES OF

INTEREST AND LIFE

HISTORY INFORMATION

Chinook Salmon

The San 

support the world' s southernmost (38 O

native spawning 

salmon Four runs of chinook occur in these

Central Valley rivers: fall

and winter. While all of 

important to managers, two stand out. First

the winter run is listed as endangered by the

State and Federal governments. Therefore, by

law, managers must 

might influence the nwnber of these 

Second, the run 

individuals, and thus of most economic

importance, occurs in the fall.

The runs are identified by the time of year

y . 

mIgratIOns (Table 4). The adults 

Sacramento and San Joaquin Rivers to spawn.

Some individuals hold in the rivers several

months before , in

most years fall-run adults begin arriving in the

upper 

spawni?g does not begin until October. Eggs

hatch m 40 to , and the 

continue development in the redds for 2 

3 weeks (Scott and Crossman, 1973; Moyle

1976), depending on water temperatures. The

fry then swim up and smoltification may occur

before 

emigrants begin their migration in January

with a peak in May (Vogel and Marine, 1991).

The 

incubation and 

migration vary with run, type of water year

discharge regime, temperature, turbidity, and

other factors. Therefore, the timing is difficult

to 

between years.

Salmon smolts migrating to the sea are the

most susceptible life stage to entrainment to

the southern Delta pwnping facilities. The

probability of entrainment increases when the

Delta-Cross Channel Gates are open and

Sacramento River water can travel to 

south 

Mokelumne River. Since the faIl run produces

the most progeny, chinook salmon smolts

observed at the TFCF usually peak in May

each year. From November , the

TFCF is operated to minimize take of chinook

salmon 

Reclamation 

criteria suggested by 

agreed upon with the California Department

ofFish and Game (Reclamation, 1992). There

are four criteria. First, the primary channel

approach velocity shall be maintained between

91 to 1.07 m/s (3.0 to 3. fils). Second,

primary bypass ratio 

between 6. Third, secondary

approach velocity shall be maintained between

9 and 1.07 m/s (3.0 and 3. fils). Fourth,

secondary bypass ratio shall be maintained

between 1.2 and 1.6.

Delta Smelt

Delta smelt is a threatened, euryhaline

osmerid endemic to the Delta that lives only
Tracy Fish Collection Facility Study

year. Delta smelt have 

extremely volatile population sizes (U.S. Fish

and Wildlife Service, 1995) and experienced

severe decreases in numbers that 

with high Delta outflows (Moyle et aI., 1992;

but see 

Resources and U.S. Bureau of Reclamation

1994). However, Delta smelt have 

exhibited resiliency. The species rebounded

strongly after the 1986 to 1992 drought, for a

short time reaching pre-drought numbers and

recolonizing Suisun Bay where they had been

extirpated.

Delta smelt are most likely to be entrained to

the TFCF during two 

history: spawning 

downstream migration. Adults spawn from

January to 

spawning at temperatures from 7 to 22 o

(45 to 72 OF). In years with low outflow

spawning usually occurs from late March

through mid-May (U.S. Fish and Wildlife

Service, 1995). Shallow 

sloughs are the areas where most spawning

occurs. Therefore, adults may be entrained to

the TFCF when these fish move out of open

water habitat in the Delta and Suisun Bay to

seek these shallower spawning habitats. The

larvae are 

become entrained to the TFCF when they are

moving toward open-water adult habitat.

Splittail

Splittail is a large 

Central Valley and is the sole extant species of

the Pogonichthys. Splittail have

experienced 

population size due to reductions in Delta

outflow. In , the

relationship between large net export years

and large splittail year classes appears to be

less strong than it once was (Meng, 

U.S. Fish and Wildlife Service, 1995).

Splittail live 

may begin to spawn at 180 to 200 mm (7. 1 to

9 in) standard length (SL) (Daniels and

Moyle 1983; personal

communication). Female splittail do 

spawn until the second year of life (Caywood

1973); usually a female is at 

(7.9 in) SL by this time. Splittail 

greatly depends on water year but may begin

in January (Wang, 

1995), continues through July, and usually

peaks between February and May (U. S. Fish

and Wildlife Service, 1995). Splittail are most

susceptible to entrainment to the TFCF at two

times. First, when 

spawning sites, they may become entrained.

Second young of the year most commonly

appear at the south Delta pumping facilities in

May through July (Meng and Moyle, 1995).

Striped Bass

Striped bass is a large-bodied, piscivorous

percichthyid exotic to , but

considered an important game fish in the

estuary. The striped bass 

smaller now than in the early 1960's (Moyle

1976).

Three habitat requirements that provide for a

highly productive striped bass fishery are a

large body of water with sufficient forage for

adult populations, a river in which to spawn

and an 

production for juvenile growth. Moyle (1976)
Tracy Fish Collection Facility Study

suggested most adults spend much of their

lives in San Pablo and San Francisco Bays. In

the fall, striped bass begin a mass migration

east to the Delta. By April, adults move to

spawning grounds. Spawning begins when the

water temperature exceeds 14.4 oc (58 OF) and

therefore usually peaks in May and early June.

The eggs are slightly negatively buoyant and

require some current to keep them off the

substrate. In the Sacramento River, eggs and

newly hatched larvae are transported to the

Delta and Suisun Bay. In the San Joaquin

eggs and larvae remain near spawning areas

because outflow and 

balanced. If the eggs and larvae never reach

the productive waters of the estuary, they may

not survive. Thus, striped bass abundance may

be correlated with the proportion of summer

outflow that is 

(Moyle, 1976). And in low water years, young

striped bass survival may be lower than in

years with higher net outflow.

Striped bass eggs, larvae, and small juveniles

are highly susceptible to entrainment during

and following the spawning season. Therefore

from May 15 to October 31 , TFCF operations

attempt to minimize take of 

improve 

Reclamation uses 

criteria agreed 

Department of Fish and Game (Reclamation

1992). These criteria are primary 

approach velocity shall be 0.30 m/s (1.0 ft/s)

and shall not 76 m/s (2.5 fils).

Primary bypass ratios shall be 

between 

velocity shall be 0.30 m/s (1.0 fils) and shall

not exceed 0. 76 m/s (2. ft/s). Secondary

bypass ratio shall be 1.2.

American Shad

American shad is a large-bodied anadromous

c1upeid introduced into the Sacramento 

between 1871 and 1881 (Skinner, 1962). A

commercial fishery existed for this fish from

1879 to 1957 (Moyle, 1976, p. 106). 

commercial fishery was then banned in favor

of a sport fishery which still exists.

Adults return from their 3- to 5-year marine

existence to the estuary in the 

March or early April, the adults migrate to

spawning grounds in the 

and its major tributaries such as the American

and Feather Rivers. Peak of the 

season depends on temperature; the optimum

temperature range of 15 to 20 oc (59 to 68 O

can typically be found in the spawning waters

from May to 

between the American shad life cycle and that

of striped bass. Like striped bass, American

shad eggs are slightly negatively buoyant and

require some 

drifting eggs hatch while being transported to

the estuary.

Like striped bass, American shad adults are

good swimmers (Bell, 1990) and thus adults

migrating upstream are not easily entrained to

the TFCF. Like striped bass eggs, American

shad eggs are 

While moving , young

American shad develop. And, by late autumn

most American shad have entered saltwater at

sizes from 8 to 2 to 7. 1 in) total

length (TL) (Moyle, 1976). American shad are

decreasingly less vulnerable to entrainment as

they grow and travel toward the ocean. At the

TFCF, young American shad 
Tracy Fish Collection Facility Study

between 80 and 120 mm (3.2 and 4. 7 in FL))

are salvaged in significant nwnbers ftom May

to December with the peak in the last portion

of this period.

White Catfish

White catfish is a carnivorous bottom-feeder

introduced into the estuary in 1874 (Skinner

1962; Miller, 1966; Moyle, 1976). Before

1953 , white catfish supported a commercial

fishery in the Delta but this was discontinued

due to overfishing (Pelgen, 1952). Although

the white 

(~ 40 cm (15.7 in) FL in 

channel 9 in) TL in

California) and slower 

catfish is more commonly 

anglers because of its 

distribution (Moyle, 1976).

White catfish live up to 11 years. Adults begin

to spawn when they reach 20 to 21 cm (7.9 to

3 in) FL; in the Delta, white catfish of this

size are typically 3 to 4 

catfish spawning 

temperatures greater than 21 o (70 O

(Borgeson and McCammon, 1967). Thus, in

the Delta, the spawning season is usually June

to July (Moyle, 1976). Either or both parents

guard the adhesive eggs deposited in a nest. At

water temperatures in the range of24 to 29 o

(75 to 84 OF), the eggs hatch in 6 to 7 days.

Individuals from 7 to 20 mm (0. 3 to 0. 8 in)

have been taken at the TFCF with plankton

nets personal 

suggesting white 

TFCF. However, the smallest size of fish

routinely counted at the TFCF is greater than

20 mm TL (0.8 in) , personal

observation). The 

salvaged seldom exceed 0.41 m (16 in) FL.

This size is usually attained in the Delta at an

age of 5 years. Thus, most white catfish may

be vulnerable to entrainment for all their lives.

White and Green Sturgeon

White sturgeon adults are capable of attaining

the largest body size (4 m (13. 1 ft) FL, 590 kg

(1,300 lb)) of any species of freshwater fish in

North America. This endemic species was

once commercially fished from the late 1860'

to 1901. Due to overfishing, the commercial

fishery was closed , 1909 to

1915 , and was ended permanently in 1917. A

sport fishery was initiated in 1954.

White sturgeon may live to be over 100 years

of age (Moyle, 1976). Adults spend most of

their lives in the estuary, and 

move upstream to spawn each 

Sacramento-San 

individual spawns 

Females mature at 11 to 12 years of age and at

sizes ranging from 1.1 to 1.5 m (3. 6 to 4. 9 ft)

FL. Males mature at 

ready to spawn, some adults may move into

lower portions of rivers in the winter. Moyle

(1976) reports spawning "seems to take place

between mid-March and early June." The eggs

are adhesive and larvae hatch within 2 weeks.

The 

hatching.

Miller (1972) reported yolk-sac larvae may be

susceptible to entrainment from March to

June. Juveniles are more likely to utilize the

upper , 1976).

Therefore the 
Tracy Fish Collection Facility Study

susceptible to entrainment to the TFCF for

some time, but the length at which they cease

to be susceptible is unknown. However, no

white 

(17. 7 in) FL have been salvaged at the TFCF.

Occasionally, juveniles and sub-adults are

found impinged on the trash rack at the Tracy

Fish Collection Facility.

The green sturgeon is native to the estuary and

may spend more time in 

white sturgeon. Fewer green sturgeon inhabit

the estuary than white sturgeon (Miller, 1972),

and green sturgeon do not attain as great an

adult size (1.3 m (51 in) FL, 45 kg (99Ib)) as

white 

reported green sturgeon may be more likely to

undertake large marine migrations compared

to white sturgeon.

APPENDIX B

REVIEW OF TRACY FISH

COLLECTION FACILITY

STUDIES: Volumes 

Since 1989 the 

(Reclamation - Mid-Pacific Region) and the

Ecological Research and Investigations Group

(Reclamation - Denver) have actively studied

the TFCF 

s. Fish and , National

Marine California

Department of Fish and Game, and the

California Department of Water 

These studies have been aimed at improving

fish salvage 

economically and 

species. Here, we review the first four major

studies that have , peerreviewed, and published in the Tracy Fish

Collection Facility Studies. The first study

described 

secondary channel (Liston et aI. , 1994).

In volwne 1 , Liston et al. (1994) described the

development and 

predator removal program in the 

channel forebay. Large predatory individuals

primarily striped bass and white catfish, were

routinely removed 

channel. Stomach analysis confirmed these

predators were feeding on diverted fish. In

addition, Liston et 

angling for predator removal. They showed

that the catch per unit effort 

angling was far 

netting. Liston et al. also evaluated striped

bass movement within 

mark/recapture experiments. These authors

found that 29 percent of 267 

released in the primary louver forebay were

recaptured in the secondary louver forebay

within 1 week of 

concluded that predator loads within the TFCF

tend to accrue over time. 

completion of volume 1 , weekly predator

removals have been implemented as standard

operating procedure at the TFCF.

In volume 2, Hiebert (1994) designed

patented and 

ichthyoplankton pump sampler 

refined the 

approximately 98 percent of eggs entrained by

the unit's pump. The 

successful with larvae, recovering 44 percent

of s pump.

Hiebert compared 

entrainment of striped bass eggs and larvae
Tracy Fish Collection Facility Study

into the TFCF 

traditional ichthyoplankton netting techniques.

In 1991 , the CIPS 

entrainment into the TFCF was 24.0 million

striped bass eggs while the 

netting estimate was 9. million 

Similarly, the CIPS unit estimate for striped

bass larvae entrained was 2. 3 million while

the ichthyoplankton netting estimate was that

0.2 million striped bass larvae were entrained

into the TFCF in 

in egg and 

suggest a high degree of 

patchiness at the TFCF. Hiebert also described

strong diel trends in the entrainment of several

species' eggs and larvae into the TFCF. The

strongest diel trend was noted for striped bass;

71 percent of an estimated 3.2 million striped

bass eggs were collected between 0000 and

0600 h.

In volwne 3 , Karp et aI. (1995) describe the

louver efficiency experiments they conducted.

All experiments were with chinook salmon

juveniles and 

found that debris load and discharge strongly

influenced louver 

salmon or striped bass. Furthermore, chinook

salmon 

efficiently at night. 

channel velocities during each experiment and

noted that the 

1992) channel velocities for target 

were not being met under all 

Karp et al.' 

independent variables that we evaluated in this

report: debris load, channel velocity, and time

of day.

In volume 4, Puckett et al. (1996) evaluated

trends in fish salvage data. These data were

acquired from 5- or 10-minute counts of fish

louvered into the holding tanks. Fish salvage

for all species of fish combined was higher in

a wet year (1993) than a critical dry 

(1994). 

salmon, striped bass, and splittail were higher

in 1993 than 

species and delta and longfin smelt, the

number of individuals salvaged was correlated

with 

seasonal correlations to aspects of species' life

histories that make them more susceptible to

entrainment in some seasons. Specific factors

appeared to coincide with salvage for different

species. For example, time of day and tide

appeared correlated with chinook salmon

splittail, and delta smelt salvage. Puckett et al.

also presented data that suggest pumping rate

/s) is directly related to the number 

salvaged for some , splittail);

however, pwnping rate also appears to interact

with a species' life history to influence

salvage rates. For example, when young

striped bass are in the vicinity of the TFCF

and pumping rates are high, salvage rate for

striped bass is higher than if pumping rate is

constrained.

With the completion of volumes 3 and 4

Karp et al. and Puckett et al. had identified

several important trends. One of 

was that among the

independent variables debris load, channel

velocity, and time of day related to salvage.