MOTE MARINE LABORATORY ... established 1955 

1600 CITY ISLAND PARK 

SARASOTA, FLORIDA 33577 

E 

TELEPHONE 813/388-4441 

1 
David 

Submitted to: 

Submitted by: 

FINE MESH SCREEN 

SURVIVABILITY STUDY 

B16 BEND UNIT 4 

TAMPA ELECTRIC COMPANY 

A Technical Report 

by Bruzek and Selvakumaran Mahadevan 

Tampa Electric Company

Post Office Box 111 

Tampa, F1 orida 33601 

Mote Marine Laboratory

1600 City Island Park 

Sarasota, F1 orida 33577 

(813) 388-4441 

December, 1986 
TABLE OF CONTENTS 

Paqe 

1.0 Introduction 1 

2.0 Study Rationale 1 

2.1 Background 1 

2.2 Station Locations 4 

3.0 Methods 4 

3.1 Laboratory Field Site 4 

3.2 Representative Important Species 6 

3.3 Sampling Procedures for FMS Survivability Studies 6 

3.3.1 Screenwash Sampling 8 

3.3.2 Organism Return Discharge (ORD) Sampling 8 

3.3.3 Control Sampling 9 

3.4 Laboratory Procedures for FMS Survivability Studies 9 

3.4.1 Latent Survival Tests 9 

3.4.2 Initial Survival Tests 10 

3.4.3 Sample Identification 10 

3.5 Data Management and Analysis 11 

4.0 Results 11 

4.1 Screenwash 11 

4.2 Organism Return Discharge 17 

4.3 Control 22 

4.4 Survivability Comparisons between Sites 27 

4.5 Survivability and Abiotic Parameters 27 

4.6 Survivability Comparisons to Prototype Study 30 

5.0 Discussion 30 

5.1 Overall Survival 30 

5.2 Effectiveness of FMS 33 

5.3 Comparison to Prototype 33 

6.0 Summary and Conclusions 35 

7.0 Literature Cited 37 

APPENDICES: FMS SURVIVABILITY STUDIES DATA 

Appendix A - Screenwash Station 

Tables A1 - A42 

bppendix B - Organism Return Discharge Station 

Tables B1 - B42 

Appendix C - Control Station 

Tables C1 - C42 
1.0 INTRODUCTION 

Tampa Electric Company is presently operating four coal-fired electric 

generating units at Big Bend Power Station. The site is located on the eastern 

shore of Tampa Bay in North Ruskin, Florida (Figure 1). All four units utilize 

once-through cooling systems; each unit circulates approximately 537cfs of 

water. The four units draw water from a single intake canal and release heated 

water to the Bay via a single discharge canal. To reduce entrainment at the 

plant, Units 3 and 4 were fitted with fine mesh screens (0.5mm); screened 

organisms are returned to the Apollo Beach northern embayment (Figure 2). 

In fulfillment of the Clean Water Act, an NPDES permit was obtained by 

Tampa Electric Company to construct and operate Unit 4. A Biological Monitoring 

Program was conducted by Tampa Electric Company in accordance with conditions of 

the NPDES Permit (No. FL 0000817) and the State of Florida Power Plant Site 

Certification (Application No. P.A. 79-12; Case No. 80-1723). The general 

requirements of the program are summarized in the Final Environmental Impact 

Statement for Tampa Electric Company, Big Bend Unit 4 (pages 4-64 through 4-66). 

This report summarizes the results of the Fine Mesh Screen Survivability 

Study, which was conducted during the spawning season of March through 

September, 1985, after Unit 4 began commercial operation (February 25, 1985). 

2.0 STUDY RATIONALE 

- . 2.1. Backsround 

Prior to the addition of Unit 4 at the Big Bend Station, concern was 

expressed for organism losses due to the operation of the Unit 4 cooling water 

intake. An initial evaluation by Tampa Electric Company indicated the potential 

for effective application of fino mesh screening (FMS) to reduce entrainment 

levels at Big Bend. Preliminary studies were conducted at the site in the 

summer of 1979 to determine whether available Representative Important Species 

(RIS) were capable of surviving impingement on a fine mesh screen under existing 

screen design conditions and to determine the relationship between specific 

1 

Y 
AREA OF STUDY 

LSE~;;OUGH~ 

BIG BEND 

ST. PETERSBURG h 

TAMPA BAY /-J 

Po 5 Nautical 

’ I Miles 

.. .igure 1. Site Location of the Big Bend Power Station. 
f 

0 3000 

1 I J 

SCALE- FEET 

Figure 2. Location of Fine Mesh Screen Sampling Stations. 

... 
a velocity/impingement duration and survival rate. The results of the 1979 

studies are presented in Appendix 3 of the August 1980 316 Demonstration (TEC: 

1980a). 

Additional detailed investigations were conducted in 1980 to test the 

biological and engineering feasibility of FMS utilizing a prototype traveling 

screen, including all features of an in-service installation. Biological 

investigations were conducted from March through August 1980. Preliminary 

results of testing through mid April were presented in Appendix 4 of the 316 

Demonstration (TEC, 1980a) Final results were summarized in the FMS report 

(TEC, 1980b). 

2.2. Station Locat -

ons

The survival studies were conducted to evaluate the effectiveness of fine 

mesh screens at the Big Bend Station. Sampling for the survival study was 

conducted at three locations pertaining to Unit 4. The screenwash station was 

in front of the screens after the organisms were screened and washed to the 

screen return; the organism return discharge (ORD) station was at the discharge 

point of the screened organisms in the northern embayment of Apollo Beach; and 

the control station was at the intake canal in front of the intake screens. 

Station locations are shown in Figure 2. 

3.0 METHODS 

Methods used during this study were essentially si'milar to those used 

during the FMS Prototype study conducted in 1980 (TEC, 1980b). 

3.1. Laboratory Field Site 

An on-site facility was established at the Big Bend station for the fine 

mesh screen survivability studies. This facility consisted of a test trailer 

with a flow-through seawater system, an adjacent office trailer, and a sample 

wash and storage trailer. The on-site facility was located along the intake 

canal near the fine mesh screens (Figure 3). All live meroplankton sortina and 

holding of organisms for 48 hours was conducted at this facility. 

4 
OFFICE 

TRAILER 

I 

L--. 

I--- - I 

I 

I 

I 

1 

I 

I

L-, -

I 

L,, 

TRAILER 

I 

Figure 3. Site Plan for Laboratory Field Station 
The test facility was a 60 foot x 12 foot trailer capable of holding 1500 

containers (500ml each) in situ (intake canal) on water tables equipped with 

once-through seawater. The trailer also had the capability for eight persons to 

1ive-sort meroplankton. The flow-through seawater system consisted of two, 1/2 

hp pumps which pumped intake canal water through 4 sand filters up to a 300 gal 

head tank. The filtered seawater was then gravity fed from the head tank to thc 

holding facility. 

The adjacent office trailer had desk space for 8 persons, equipment for 

vial preservation and transport, and a net and equipment storage area. 

The sample wash trailer was used to rinse samples and equipment and for 

the storage of retained samples. 

3.2. Representative Important Species 

The survival studies were designed to concentrate on certain target 

species which were found in high abundance in the 1980 studies (TEC, 1980b). 

These Representative Important Species (RIS) were: 

h-""-7- Anchoa mitchilli - eggs, prolarvae and postlarvae; i" 

SG+W Harenqul a jaguana - eggs, pro1 arva2 and pc;stl arvae; 

k-2 Sciaenidae - eggs, prclarvae and postlarvae; 

+,.& caa--b Meni.ppe mercenari a - zoea and mega1 ops ; 

y~d-c-I,ny Upogebia sp. - mysis and postlarvae. 

In addition, eggs and larvae of other fish species which appeared in 

large numbers; and any juveniles which were collected were held in latent 

mortality experiments. Because of the difficulty of distinguishing larvae of 

Menippe and llpogebia during live sorting, zoea and larvae of a number of 

crustacean species were held in latent mortality tests. 

3.3. Sampling Procedures for FMS Survivability Studies 

Fine mesh screen (FMS) field studies commenced the first week of March 

1985. Field studies were conducted each week from March 5, 1985 until October 

1, 1985, for a total of 31 weeks of sampling. (See Table 1 for actual dates.) 

Two collections per day and two per night were taken at the screenwash 

6 
Table 1. Sampling dates for the FMS Survivability Study. 

Survival Studies 

March 5, 1985 

March 11, 1985 

March 18, 1985 

March 25, 1985 

April 2, 1985 

April 8, 1985 

April 16, 1985 

April 22, 1985 

April 29, 1985 

May 6, 1985 

May 13, 1985 

May 20, 1985 

May 28, 1985 

June 3, 1985 

June 10, 1985 

June 18, 1985 

Survival Studies 

June 25, 1985 

July 1, 1985 

July 9, 1985 

July 16, 1985 

July 23, 1985 

July 30, 1985 

August 6, 1985 

August 14, 1985 

August 20, 1985 

August 27, 1985 

September 4, 1985 

September 10, 1985 

September 17, 1985 

September 23, 1985 

October 1, 198~ 

7 
c 

1 

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x 

e 

f 

P 

and ORD stations one day each week. One collection per day and one per night 

were taken from the control station one day each week. 

3.3.1. Screenwash Sampling 

The low and high pressure screenwash of the fine mesh screens emptied 

into a common trough which flowed to a sump at the beginning of the orgmjsz 

return system. The screenwash station was sampled by suspending a lm mouth 

diameter, 505 micron mesh net in front of the trough where it emptied into the 

sump basin at the beginning of the organism return system. A bucket attached to 

the cod end of the net was used to collect organisms retained by the net. A PVC 

frame inside the net held it open, reducing damage to the organisms from 

friction against the net. The net was fished for 3 minutes, and a11 organisms 

retained were carefully rinsed down into the bucket. Abiotjc measurements 

including temperature, dissolved oxygen, salinity, and conductivity were taken 

in the sump prior to net sampling. The status of the screens, including the 

number of screens, screenwash pumps and condenser cooling pumps operating, as 

well as whether the bypass gates were open or closed was recorded during each 

sampling. The sample was then immediately returned to the test trailer for 

sorting. 

3.3.2. Organism Return Discharqe (ORD) Sampling 

The ORD pipes exit at the end of a walkway which extends 500 feet along a 

sheet pile wall in the Apollo Beach northern embayment. The ORD station was 

sampled using a specially constructed 505 micron mesh net supported by a 

floating rectangular frame (2.5 ft x 4 ft). The net was positioned under the 

flow from the discharge pipe, and organisms retained were carefully rinsed down 

to a bucket attached to the cod end of the net. The net was fished for 3 

minutes. Abiotic measurements including temperature, dissolved oxygen, 

salinity, and conductivity were taken in the discharge area prior to net 

sampling. The sample was returned to the holding trailer immediately after 

collection. 
3.3.3. Control Sampl i ng 

The control sample was taken by lowering a standard 1 meter mouth 

diameter, 505 micron mesh net from a walkway bridge over the intake canal. 

Enough line was released to allow the net to sink to mid depth, where it was 

allowed to fish for 15 minutes. The continual flow of the intake canal was 

suffic.ient enough to allow for adequate sampling from the stationary net. 

Organisms retained 'by the net were carefully rinsed to the cod end of the net, 

and the contents were then carefully poured into a bucket of ambient intake 

water. Abiotic measurements, including temperature, dissolved oxygen, salinity, 

and conductivity, were taken in the intake canal prior to net sampling. The 

sample was returned to the holding trailer immediately after collection. 

3.4 Laboratory Procedures For FMS Survivability Studies 

3.4.1. Latent Survival Tests 

The latent survival tests were conducted to examine the delayed survival 

response of the target species and other abundant species impinged on the 

screens. 

Samples obtained from the screenwash, ORD, or control stations were 

brought to the test trailer, where a subsample was taken by the sorting 

supervisor. The subsample was then sorted using glass trays on a lighted table 

equipped with flow-through water. The sorted organisms were placed in 

individually marked jars (5 to a jar); the jar number and contents were recorded 

and checked by the holding supervisor. The jars were .-then placed on the 

appropriate water table for the latent survival tests. For each sample, up to 

30 test.organisms of each lifestage of the species were held, where possible. 

Crab zoea were held in individual compartments of plastic tackle boxes (to avoid 

cannibalism). Once the organisms for holding were drawn off the first 

subsample, the rest of the RIS were sorted as live or dead and preserved in 

separate vials (initial survival). If a total of 30 organisms for each species 

and lifestage was not available from the first subsample, a second subsample was 

drawn and sorted only for the live holding organisms necessary. The procedure 

9 
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7. 

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1 

was repeated once more, if necessary. A maximum of 3 subsamples per sample were 

processed. Once the organisms for holding and initial survival were removed 

from the sample, the remains were preserved and stored in labelled jars. 

Latent survival observations were performed at 6, 12, 24, 36, and 48 

hours after the collection time. The number of remaining live and dead 

organisms in each test container was recorded' on the data sheet. Observations 

such as hatching of eggs or missing organisms were also recorded. Dead 

organisms were removed from the jars, placed in labeled vials, preserved in 

formalin, and stored in transport trays for later transfer to Mote Marine 

Laboratory (MML). At the end of the 48 hour period, all remaining live 

org,anisms were placed in labeled jars, preserved, and taken to MML. 

3.4.2. Initial Survival Tests 

Initial survival tests were conducted to examine the survival of the 

organisms immediately after the collection of samples from the screenwash, 

-organism return canal, and control stations. The first subsample was sorted to 

obtain the necessary numbers of organisms for the latent survival tests; the 

remainder of the subsample was then sorted into live and dead RIS organisms for 

estimating initial survival. The sorted organisms were placed into separate 

labeled vials for live or dead, then preserved in formalin and stored for later 

identification at MML. The sorting process was limited to a maximum of two 

hours after sample collection in order to minimize handling mortality. Initial 

survival observations were performed on the lifestages of the RIS species only. -. 

3.4.3. Sample Identification 

The vials of preserved organisms were placed in a transport rack at the 

field site for transfer to MML. A custody sheet with the vial number and 

position of vials in the rack accompanied it during transport, to avoid 

potential loss of data during sample transfer. 

Organisms were sorted and identified at MML. Identifications were made 

through the use of standard literature sources and MML reference collection. 

The sample number, species name, lifestage and number were recorded on bench 

10 
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sheets for later computer entry. A voucher reference collection of f 

i taxonomically confirmed species was maintained. 

3 3.5. Data Management and Analysis i 

Computer files were created with data entered directly from benchsheets 

or logbooks and using a dBASE I1 database program. Printouts were checked and 

corrections made to e'nsure the accuracy of the databases. Manipulation and 

analysis of data was then performed using standard computer packages on an IBM 

compatible Zenith 100 system. 

1 

1 

1 4.0 RESULTS 

Initial and latent Survivability of selected taxonomic groups were 

analyzed for the screenwash, organism return discharge, and control stations. 

B 

t 

Results are reported for day and night samplings per month, as well as overall 

ii mean values. Abiotic data collected in conjunction with the FMS survivability 

$ tests are tabulated and presented in Table 2. 

1 

4.1. Screenwash Stations 

iI Mean initial survivability of selected taxonomic groups collected at the 

screen wash station is presented in Table 3. Initial survivability and percent 

! hatchability of selected eggs collected from day and night samplings of March 

through September 1985 are given in Appendix A, Tables A-1 through A-7. 

1 Similarly, initial survivability of selected fish larvae i's provided in Appendix 

A, Tables A-8 through A-14. The initial survivability of selected invertebrates 

7 collected from day and night samplings March through September is given in 

Appendix A, Tables A-15 to A-21. 

i Of the eggs collected from the screenwash station samplings, only two 

taxonomic groups, the Engraulids and the Sciaenids, were collected in sufficient 

numbers for meaningful analysis (Table 3). Engraulids eggs bad an overall 

1 initial survivability of 48%, and wet-e collected from all months with the 

greatest numbers and survival seen duriq the day samplings. Sciaenid eggs 

f 

-

11 
Table 2. Mean values of abiotic measurements taken during the 

FMS Survivability study. 

SCREENWASH 

March April May June July August September 

Temperature 22.6 25.2 28.2 30.9 30.6 30.8 28.5 

(OC) 

Dissolved 8.0 7.7 6.8 6.7 6.8 6.1 6.8 

Oxygen (mg/l) 

Salinity (ppt) 38.6 29.5 30.7 33.3 30.9 27.7 25.5 

Conductivity 42.4 45.3 50.1 52.8 51.6 44.6 41.1 

(mmhos) 

ORGANISM RETURN DISCHARGE 

Temperature 24.2 27.0 31.1 32.5 32.3 32.6 31.5 

(OC) 

Dissolved 7.5 6.8 6.5 5.4 5.8 5.6 6.1 

Oxygen (mg/ll 

Salinity (ppt) 28.9 29.9 30.8 31.5 31 .O 29.3 25.5 

Conductivity 44.1 47.4 53.0 54.7 52.8 $8.9 43.9 

(mhos) 

CONTROL 

Temperature 22.2 24.7 28.1 31.2 30.4 30.5 28.7 

(OC) 

Di ssolved 8.3 7.6 7.4 7.3 6.7 6.5 9.5 

Oxygen (ms/l) 

Salinity (ppt) 28.4 29.5 30.3 31.1 30.6 28.5 24.5 

Conductivity 40.7 44.4 50.0 52.7 50.5 46.5 36.8 

(mmhos) 
-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

Table 3. Summary data of initial survivability tests at Screenwash Station,

Big Bend Power Station (1985). 

-

FISH

EGGS: 

CLUPEIDAE 

ENGRAULIDAE 

SCIAENJDAE 

SOLEIDAE 

LARVAE: 

CLUPEIDAE 

ENGRAULIDAE 

ATHERINIDAE 

SPAR1DAE 

Lagodon rhomboides 

SCIAENIDAE 

Bai rdiel1a chrysoura

Poqonias cromis 

Cynoscion nebulosus 

Cynoscion arenarius 

Leiostomus xanthurus 

BLENNIIDAE 

GOBIIDAE 

SOLEIDAE 

INVERTEBRATES 

ZOEA: 

PENAEIDAE 

CARIDEA 

PORTUNIDAE 

PAGURIDAE 

XANTHIIDAE 

PINNOTHERIDAE 

GRAPSIDAE 

MEGALOPS : 

XANTHII DAE 

GRAPSIDAE 

INITIAL SURVIVABILITY 

Total # 

Organisms

Tested Mean S.D. 

219 0.78 0.04 

21,899 0.48 0.36 

51 202 0.63 0.03 

29 0.88 0.18 

2 0.50 0.71 

1,651 0.16 0.04 

1 0.00 0.00 

1 0.00 0.00 

1,632 0.61 0.33 

2 0.00 0.00 

1 0.00 0.00 

25 0.00 0.00 

3 0.25 0.35 

107 0.10 0.00 

35 0.00 0.00 

' 6 1.oo 0.00 

l ,057 c.72 0.01 

45 0.94 0.07 

83 0.56 0.04 

11 143 0.93 0.04 

33,287 0.89 . 0.06 

512 0.92 0.07 

25 0.77 0.33 

149 0.82 0.20 

13 
exhibited an overall initial survivability of 63%, and were collected from all 

months with the highest numbers being collected at night. The hatchability of 

eggs that were held in the latent mortality tests is an index of the viability 

of the live eggs that initially survived. Hatchability data is summarized in 

Table 33. Both the Engraulid and Sciaenid eggs had average hatchability of 

greater than 70%. 

Of the larvae collected for initial survivability testing, only Engraulid 

and Sciaenid larvae were collected in sufficient numbers for meaningful 

analysis. Engraulid larvae had an overall mean initial survivability of 16%, 

while Sciaenid larvae exhibited 61% (Table 3). Both showed 1 ittle difference 

between day and night samplings. 

Invertebrates had the highest overall initial survival, exceeding that of 

fish larvae (Table 3). Caridean zoea had initial survivability of 72%, with no 

difference between day and night sampling. Xanthiidae zoea had 93% initial 

survivability, with larger numbers 'collected during the day but no difference in 

day/night survival. Pinnotheridae zoea had initial survivability of 89%, with 

larger numbers tested from day sampling but no differences in survival. 

Grapsidae zoea had 92% initial survivability; most individuals were collected 

during the day, but no differences in survival between day and night were 

exhibited. Megalops larvae were not collected in sufficient numbers for 

meaningful analysis. 

Latent survival was examined at 24 and 48 hrs and data is summarized in 

Tables 4 and 5. Since egg development time of selected taxonomic groups tested 

was generally less than 48 hrs, eggs were tested only for-initial survivability 

and hatchability. The 24 hr and 48 hr latent survivability of selected hatched 

fish larvae collected from day and night samplings .at the screenwash for March 

through September 1985 is given in Appendix A, Tables A-22 to A-28, the 24 hr 

and 48 hr 1atent survivabil i ty of selected fish 1arvae collected from samplings 

at the screenwash March through September is given in Appendix A, Tables A-29 to 

A-35, and the latent survivability of select invertebrates collected during this 

period is presented in Appendix A, Tables A-36 through A-42. 

Of the larvae which were collected in sufficient numbers, the Engraulids 

14 
-- -- 

-- -- 

-- 

-- 

-- 

-- 

-- 

-- 

Table 4. Summary data of latent survivability tests for 24 and 48 hours,

Screenwash Station, Big Bend Power Station (1985). 

LATENT SURVIVABILITY 

Total # 

Organisms 24 hrs 48 hrs 

Tested Mean S.D. Mean S.D. 

-

FISH

EGGS: 

CLUPEJDAE 

ENGRAULIDAE 

SCIAENIDAE 

SOLEIDAE 

LARVAE: 

CLUPEIDAE 

ENGRAULIDAE 

ATHERINIDAE 

SPARIDAE 

Laqodon rhomboides 

SCIAENIDAE 

Bairdiella chrysoura

Pogonias cromis 

Cynoscion nebulosus 

Cynoscion arenarius 

Leiostomus xanthurus I BLENNIIDAE 

GOBIIDAE 

SOLEIDAE 

INVERTEBRATES 

ZOEA: 

PENP.EIDAE 

CAR1DEA 

PORTUNIDAE 

L PAGURIDAE

XANTHIIDAE

PINNOTHERIDAE 

i GRAPSIDAE 

: 

i 

MEGALOPS : 

XANTHIIDAE 

GRAPSIDAE 

JUVENILES: 

Lo11 i quncula brevi s 

4 0.25 0.35 

322 0.45 0.13 

549 0.44 0.04 

8 0.30 0.18 

28 0.59 0.12 0.44 0.16 

2,200 0.77 0.10 0.68 0.04 

1 0.00 0.00 0.00 0.00 

1 0.00 0.00 0.00 0.00 

1,852 0.73 0.02 0.63 0.04 

6 0.50 0.50 0.50 0.50 

7 1-00 0.00 1.00 0.00 

2 0.50 0.71 0.50 0.71 

143 0.57 0.04 0.44 0.13 

15 0.62 0.28 0.62 0.28 

39 0.39 0.55 0.36 0.32 

941 0.98 0.03 0.96 0.04 

52 0.95 0.07 0.95 0.07 

1,992 0.78 0.01 0.07 0.06 

34 0.96 0.06 0.81 0.03 

97 0.77 0.07 0.76 0.09 

1,771 0.88 0.02 0.80 0.06 

3,499 0.85 0.00 0.71- . 0.04 

176 0.91 0.07 0.85 0.03 

215 0.99 0.02 .0.97 0.04 

1,230 0.98 0.01 0.95 0.00 

44 0.03 0.01 0.02 0.03 

15 
-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

Table 5. 

Taxa 

Clupeidae 

Anchoa mitchilli 

Atheri ni dae 

Spari dae 

Laaodon rhomboides 

Sci aenidae 

Bai rdiell a chrysoura 

Poqonias cromis 

Cynoscion nebulosus 

Cvnoscion arenarius 

Leiostomus xanthurus . 

Bl enni idae 

Gobi idae 

Sol eidae 

Summary of the latent survival of fish larvae from 

Big Bend Screenwash Station for 24 and 48 hours, 

for all samplings. (1.00 = 100% survival). 

24 hrs 48 hrs 

No. 

Tested Mean S.D. Me an S.D. 

5 0.50 0.00 0.50 0.00 

105 0.75 0.40 0.73 0.39 

3 0.66 0.57 0.66 0.57 

275 0.80 0.31 0.69 0.34 

6 0.66 0.51 0.66 0.51 

5 1.GO 0.00 1.oo 0.90 

1 0.00 0.00 0.00 0.00 

151 0.56 0.39 0.45 0.42 

5 0.60 0.54 0.60 0.54 

35 0.69 0.42 0.60 0.47 

34 0.91 0.25 --0-88 0.28 

Mean survival (percent: multiply by 100)

S.D. = Standard deviation 

16 
which hatched from collected eggs had 77% 24 hr latent survivability and 68% 48 

hr survivability. Hatched Sciaenidae larvae exhibited 73% 24 hr survivability 

and 63% 48 hr latent Survivability. Hatched larvae of the family Soleidae had 

24 hr latent survivability of 98% and 48 hr survivability of 96% (Table 4). The 

latent survival of. fish collected as larvae is summarized in Table 5. Anchoa 

mitchilli larvae had a latent 48 hr survivability of 73%, and Sciaenidae larvae 

had a latent 48 hr survival of 69%. Cynoscion arenarius was the only other 

1arva.e collected in sufficient numbers and had a 48 hr latent survival of 45%. 

The latent survival of these abundant groups showed no significant differences 

between collected !arvae and larvae hatched from collected eggs. 

Invertebrate larvae generally showed higher latent survivability than did 

fish larvae (Table 4). Caridean zoea had 24 hr latent survivability of 78% and 

48 hr survivability of 67%. Xanthiidae zoea had 24 hr latent survivability of 

88% and 48 hr survivability of 80%. Pinnotheridae zoea had 24 hr latent 

survivability of 85% and 48 hr survivability of 71%. Grapsidae larvae were the 

only megalops collected in sufficient numbers for meaningful latent 

survivability analysis; they exhibited 98% and 95% 24 hr and 48 hr'latent 

survivability, respectively. 

4.2. Organism Return Discharge 

Mean initial survivability of selected taxonomic groups collected at the 

ORD station is given in Table 6. Initial survivability and percent hatchability 

of selected eggs collected from day and night sampling, March-September 1985 are 

presented in Appendix 3, Tables B-1 through B-8. Appendix B, Tables B-9 

through 8-14show initial survivability of selected fish larvae collected from 

day and night sampling (March-September). Initial survivability of selected 

invertebrate 1arvae collected from day and night sampling (March-September) is 

given in Appendix B, Tables B-15 through B-21. 

Two groups of eggs were collected in sufficient numbers for meaningful 

analysis (Table 5). Engraulidae eggs were collected mostly during the day and 

had mean initial survivability of 29%; surviving eggs had a hatchability 

exceeding 90% (Table 13). Sciaenidae eggs had mean initial survivabiiity of 

1 

f 17 

90 
-- -- 

-- -- 

-- -- 

-- 

-- 

-- 

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Table 6. Summary data of initial survivability tests at the Organism Return 

Discharge Station, Big Bend Power Station (1985). 

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FISH

EGGS: 

CLUPEIDAE 

ENGRAULIDAE 

SCIAENIDAE 

SOLEIDAE 

LARVAE: 

CLUPEIDAE 

ENGRAULIDAE 

ATHERINIDAE 

SPARIDAE 

Lagodon rhomboides 

SCIAENIDAE 

Bairdiella chrysoura

Pogonias cromis 

Cynoscion nebulosus 

Cynoscion arenarius 

Leiostomus xanthurus 

BLENNIIDAE 

GOBIIDAE 

SOLEIDAE 

INVERTEBRATES 

ZOEA: 

PENAEIDAE 

CAR1DEA 

PORTUNIDAE 

PAGURIDAE 

XANTHIIDAE 

PINNOTHERIDAE 

GRAPSIDAE 

MEGALOPS: 

XANTHIIDAE 

GRAPSIDAE 

i 

INITIAL SURVIVABILITY 

Total # 

Organisms

Tested Mean S.D. 

9 0.49 0.13 

3,522 0.29 . 0.21 

16,693 0.40 0.04 

23 0.56 0.20 

2 0.00 0.00 

271 0.58 0.60 

284 0.56 0.16 

11 0.00 0.00 

1 1-00 0.00 

5 0.00 0.00 

1. 0.00 0.00 

2 0.50 0.00 

458 0.70 0.02 

7 1.00 0.00 

21 0.79 0.23 

7 ,576 0.90 .. - 0.01 

29 ,845 0.83 0.07 

442 0.96 0.06 

5 0.50 0.71 

109 0.76 0.08 
40%, were collected in higher numbers during the night and had a hatchability of 

approximately 80%. 

Of the fish larvae collected at the ORD, only two groups were collected 

in sufficient numbers for meaningful analysis (Table 6). Engraul idae larvae, of 

which 271 organisms were tested, exhibited initial survivability of 58%. 

Sciaenidae larvae had initial sdrvivability of 56%. For both of these groups 

there were not sufficient numbers represented in the collections for a 

determination of day/night or monthly comparisons in survivability. i Invertebrate larvae exhibited the highest survivability of all larvae 

collected at the ORD .(Table 6). Four groups of invertebrate larvea were 

1 considered for detailed analysis of initial survivability. Caridean zoea had 

70%, with no apparent difference between day/night or monthly collections. 

Initial survivability for Xanthidae zoea was 90%, with more larvae being 

collected during the day but no apparent difference in day/night initial 

survivability. Pinnotheridae zoea, the most abilndant zoea collected at the ORD, 

had mean initial survivability of 83%. More of these zoea were collected during 

the day, with no apparent difference in survivability between day and night. 

Grapsidae larvae had initial survivability of 96% 'but were not present in 

sufficient numbers for accurate day/night or monthly survivability 

determinations. No megalops were collected in sufficient numbers for meaningful 

survivability analysis (Table 5). 

Mean 24 hr and 48 hr latent survival data of selected taxonomic groups 

collected at the ORD is summarized in Tables 7 and 8. The 24 hr and 48 hr 

latent survivability of selected fish larvae hatched from'eggs collected in day 

and nil;ht samplings for March-September 1985 is shown in Appendix B, Tables B-22 

through B-28. The 24 hr and 48 hr latent survivability of fish larvae collected 

at the ORD, March through September, is shown in Appendix B, Tables 8-29 through 

6-35. Latent survivability of selected invertebrate larvae for 24 hrs and 48 

hrs collected in day and night samplings, March-September, is presented in 

Appendix B, Tables 6-36 through B-42. Of the fjsh larvae hatched from collected 

eggs, three were of sufficient numbers for meaningful analysis (Table 7). 

Engraulidae larvae had 24 hr latent survivability of 86% and 43 hr latent 

19 
-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

Table 7. Summary.data of latent survivability tests for 24 and 48 hours,

Organism Return Discharge Station, Big Bend Power Station (1985). 

LATENT SURVIVABILITY 

Total # 

Organi srns 24 hrs 48 hrs 

Tested Mean S.D. Mean S.D. 

-

FISH

EGGS: 

CLUPE IDAE 2 0.50 0.00 

ENGRAULIDAE 128 0.44 0.06 

SCIAENIDAE 505 0.42 0.01 

SOLE IDAE 7 0.65 0.02 

LARVAE: 

CLUPEIDAE 3 1.00 0.00 1.00 0.00 

ENGRAULIDAE 1$249 0.86 0.05 0.65 0.11 

ATHERINIDAE 4 0.16 0.23 0.16 0.23 

SPARIDAE ” - -I 

Lagodon rhornboides 

SCIAENIDAE 

2 

1,376 

1.00 

0.83 

0.09 

0.06 

1-00 

0.66 

0.00 

0.00 

Bairdiel 1a chrysoura

Pogonias cromis 1 1.00 9.00 1.oo 0.00 

12 0.34 0.47 0.34 0.47 

2 0.50 0.71 0.50 0.71 

GOBIIDAE 7 0.67 0.47 0.67 0.47 

SOLEIDAE a73 0.93 0.09 0.90 0.11 

Cynoscion nebul osus 

INVERTEBRATES 

ZOEA: 

PENAEIDAE 27 0.99 0.00 0.97 0.03 

CARIDEA 

PORTUNIDAE 

2,118 

6 

0.79 

0.88 

0.00 

0.17 

0.66 

0.90 

0.00 

0.14 

PAGURIDAE 76 0.81 0.09 0.68 0.14 

XANTHIIDAE 

PINNOTHERIDAE 

GRAPS IDAE 

1,799 

3,674 

192 

0.81 

0.80 

0.94 

0.04 

0.00 

0.03 

0.71 

0.65‘ 

0.89 

0.06 

0.00 

0.03 

MEGALOPS: 

XANTHIIDAE 72 0.93 0.07 0.92 0.08 

GRAPSIDAE 1,469 0.96 0.03 0.94 0.04 

JUVENILES: 

Lo11iguncula brevis 4 0.00 0.00 0.00 0.00 
-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

Table 8. Summary of the latent survival of fish larvae from 

Big Bend Organism Resturn Discharge Station for 24 

and 48 hours, for a17 samplings. (1.00 = 100% 

survival). 

24 hrs 48 hrs 

No. 

Taxa Tested Mean S.D. Mean S.D. 

Clupeidae 

Anchoa mitchilli 

At tieri ni dae 

Spari dae 

Laqodon rhomboides 

Sciaenidae 

Bairdiella chrvsoura 

Poqonias crornis 

Cvnoscion nebulosus 

Cvnosci on arenari us 

Leiostomus xanthurus 

B1 enni idae 

Gobi idae 

Sol ei dae 

0.93 0.16 0.76 0.33 

1.oo 0.00 1.00 0.00 

0.85 0.28 0.70 0.37 

1.00 0.00 1.oo 0.00 

1.oo 0.00 1.oo 0.00 

0.41 0.46 0.33 0.44 

0.50 0.70 0.50 0.70 

0.60 0.54 0.40 0.54 

1.!lo 0.00 0.95 0.22 

Mean survival (percent: multiply by 100)

S.D. = Standard deviation 

21 
survivability of 65%, with no difference in survivability between day and night 

samples. Sciaenidae larvae had 24 hr latent survivability of 83% and 48 hr 

latent survivability of 66%; there was no apparent difference between day/night 

or monthly samples. Soleidae larvae had 24 hr and 48 hr latent survivability of 

93% and 90%, respectively. Almost all of the Soleidae larvae were collected 

during the day; there was no difference in survivability between monthly 

samplings. The 24 hr and 48 hr latent survivability of fish larvae collected at 

the ORD is summarized in Table 8. Anchoa mitchilli larvae had a 48 hr latent 

survivability of 76%, and Sciaenidae larvae had a 48 hr latent survivability. of 

70%. The mean latent survival values for these larvae slightly exceeded the 

latent survival values for these larvae hatched from eggs collected at the ORD, 

though the differences were not significant. I. 

Latent survivability of the invertebrate larvae was similar to that of 

fish larvae (Table 7). Caridean zoea had 24 hr and 48 hr latent survivability 

of 79% and 66%, respectively. Equal numbers of zoea were tested from day and 

night samples with no apparent difference in Survivability. Xanthidae zoea had 

24 hr latent survivability of 81% and 48 hr latent survivability of 71%. There 

was no difference in numbers or survivability of these zoea between day and 

night samplings. Pinnotheridae zoea exhibited 24 hr and 48 hr latent 

survivability of 80%.and 65%, respectively. There was no apparent difference 

between day and night or monthly samplings for these zoea. The only megalops 

which were collected in sufficient numbers for analysis were thos. of the family 

Grapsidae, which had 24 hr latent survivability of 96% and 48 hr survivability 

of 94% (Table 7). There was no difference in latent survivability between day 

and night or monthly samplings of these megalops. 

4.3. Control 

Mean initial survivability of selected taxonomic groups collected at the 

control station is summarized in Table 3. Initial survivability and percent 

hatchability of selected eggs collected from day and night sampling for 

March-September 1985 are shown in Appendix C, Tables C-1 through C-7. Appendix 

C, Tables C-8 through C-14 present the initial survivability of selected larvae 

22 
-- -- 

-- -- -- 

-- -- -- 

Table 9. Summary data of initial survivability tests at the Control Station, 

Big Bend Power Station (1985). 

1 

1 -

FISH

EGGS: 

CLUPEIDAE 

ENGRAULIDAE 

SCIAENIDAE 

SOLEIDAE 

LARVAE: 

CLUPEIDAE 

ENGRAULIDAE 

ATHERINIDAE 

SPARIDAE 

Laqodon rhomboides 

SCIAENIDAE 

Bairdiell a chrysoura

Pogonias cromis 

Cynosci on nebul osus 

Cynoscion arenarius 

Leiostomus xanthurus 

BLENNIIDAE 

GOBIIDAE 

I 

f. SOLEIDAE 

? INVERTEBRATES 

ZOEA: 

PENAEIDAE 

CARIDEA 

PORTUNIDAE 

PAGURIDAE 

XANTHIIDAE 

PINNOTHERJDAE 

GRAPSIDAE 

MEGALOPS: 

XANTHIIDAE 

GRAPSIDAE 

INITIAL SURVIVABILITY 

Total # 

Organisms

Tested Meam S.D. 

60 0.73 0.38 

16,378 0.72 0.31 

5,872 0.72 0.05 

3 1.00 0.00 

303 0.16 0.09 

3 0.00 0.00 

95 0.22 

12 0.60 0.57 

14 0.50 0.71 

35 0.00 0.00 

347 0.65 0.09 

14 1.00 0.00 

5 1-00 0.00 

671 0.88 0.10 

2,987 0.77 - - 0.13 

37 0.81 0.11 

1 3-00 0.00 

24 0.84 0.08 

23 

G 
T 

I 

i 

1 

7 

i 

from day and night collections for March-September. Initial survivability of 

selected invertebrate 1arvae col1 ected from day and night sampl i ng, 

March-September is given in Appendix C, Tables C-15 through 8-21. 

Two taxonomic groups of eggs were collected in sufficient numbers for 

initial survivability analysis; those were Engraulidae eggs with mean initial 

survivability of 72% (Table 9) and percent hatchability of greater than 95% 

(Table 13), and Sciaenidae eggs with mean initial survivability of 72% and 

hatchability of greater than 90%. For Engraulidae eggs there was no difference 

in survivability between day/night or monthly samples. Most Sciaenidae eggs 

were collected during night samplings; there was no apparent difference in 

survivability between day/night or monthly samplings. 

Fish larvae collected during'the control sampling were not present in 

sufficient numbers for meaningful initial survivability testing. Engraulidae 

larvae had initial survivability of 16%; however, only 303 individuals were 

available for this testing. Sciaenidae larvae exhibited 85% initial 

survivability, but only 95 individuals were tested. 

Two taxonomic groups of selected invertebrate larvae were present in 

sufficient numbers for meaningful initial survivability testing (Table 9). 

Xanthidae zoea had mean initial survivability of 85%, and there was no 

difference in initi-a1 survivability between day/night or monthly samples. 

Pinnotheridae zoea had mean initial survivability cf 72%, with no apparent 

difference in survivability between day/night or monthly samples. 

The 24 hr and 48 hr latent survivability of selected taxonomic groups is 

summarized in Tables 10 and 11. The 24 hr and 48 hr latent survivability of 

fish larvae hatched from collected eggs for day/night sampling from 

March-September is shown in Appendix C, Tables C-22 through C-28. The 24 hr and 

48 hr latent survivability of fish larvae collected at the control station, 

March through September, is given in Appendix C, Tables C-29 through C-35. For 

day and night sampling, March-September, the 24 and 48 hr latent survivability 

of selected invertebrate larvae is presented in Appendix C, Tables C-36 to C-42. 

Hatched Engraulidae larvae had 24 hr latent survivability of 70% and 48 

hr latent survivability of 59% (Table 10). Most individuals tested were from 

i 24 

J? 
-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

Table 10. Summary data of latent survivability tests for 24 and 48 hours,

Control Station, Big Bend Power Station (1985). 

LATENT SURVIVABILITY 

Total # 

Organisms 24 hrs 48 hrs 

Tested Mean S.D. Mean S.D. 

-

FISH

EGGS: 

0.74 

0.59 

0.46 

CLUPEI DAE 

ENGRAULIDAE 

SCIAENIDAE 

SOLEIDAE 

LARVAE: 

CLUPEI DAE 

ENGRAULIDAE 

ATHERINIDAE 

SPARIDAE 

Lagodon rhomboides 

S CIAENIDAE 

GOBIIDAE 

SOLEIDAE 

INVERTEBRATES 

ZOEA: 

PENAEIDAE 

CARIDEAN 

PORTUNIDAE 

PAGURIDAE 

XANTHIIDAE 

PINNOTHERIDAE 

GRAPSIDAE 

M EGALOPS: 

XANTHJIDAE 

GRAPSIDAE 

JUVENILES: 

Lo11 iguncul a brevis 

0.00 

0.21 

0.06 

0.00 

0.18 

0.21 

0.17 

1 

30 

109 

1 

23 

1,361 

49 

0.50 

0.51 

0.56 

0.50 

0.88 

0.70 

0.52 

0.00 

0.61 

0.50 

0.00 

0.11 

0.50 

0.00 

0.77 

0.50 

1 

902 

6 

3 1.oo 0.00 1.00 

0.65 

0.75 

0.78 

0.78 

0.95 

147 

156 

285 

0.08 

0.31 

0.01 

1.oo 

0.88 

0.67 

0.82 

0.85 

0.74 

0.88 

1.00 

1.00 

0.00 

c.00 

0.C8 

0.47 

0.10 

0.06 

0.13 

9.00 

0.00 

0.00 

0.00 

0.00 

0.03 

0.00 

0.00 

0.05 

0.06 

0.03 

0.00 

0.00 

0.00 

1.00 

0.95 

1.00 

1.oo 

0.90 

0.86 

0.93 

1.oo 

1.oo 

0.00 

1 

1,362 

14 

44 

750 

1,281 

107 

28 

261 

1 
-- 

-- 

-- 

-- -- -- 

-- -- -- -- 

Table 11. Summary of the latent survival of fish larvae from 

Big Bend Control Station for 24 and 48 hours, for 

a1 1 sampl ings. (1 .OO = 100% survival). 

24 hrs 48 hrs 

No. 1 Taxa Tested Mean S.D. Mean S.D.

C1upeidae 

1 Anchoa mi tchill i 209 0.61 0.38 0.52 0.37 

Atheri n idae 42 0.35 0.39 0.29 0.40 

I

I 

Sparidae 

Laqodon rhornboides 1 0.00 0.00 0.00 0.00 

f

1 Sciaenidae 100 0.78 0.38 0.74 0.33 

Bai rdi el 1a chrysoura 

Poqonias cromis 

=

.

i Cynosci on arenari us 

Leiostomus xanthurus 

B1 enni idae 141 0.82 0.27 0.67 0.36 

P 

t Gobi idae 144 0.77 0.29 0.74 0.29 

Sol eidae 10 1.oo 0.00 0 :77 0.44 

Cvnoscion nebul osus 

Mean survival (percent : mu1ti ply by 100)

S.D. = Standzrd deviation 

26 
day samples, and there was no apparent difference between monthly samplings. 

Hatched Sciaenidae larvae had 24 hr latent survivability of 77% and 48 hr latent 

survivability of 61%, with higher survivability in night samples, when compared 

to day samples. The 48 hr latent survival of collected Anchoa mitchilli larvae 

was 52%, and that of collected Sciaenidae larvae was 74%. These values were 

similar to those of the hatched 1 arvae. 

Of the invertebrates collected for latent mortality testing, three 

taxonomic groups were considered for detailed analysis (Table 10). Caridean 

zoea had 24 and 48 hr latent survivability of 95% and 88%, respectively. There 

was no difference in latent survivability between day/night or monthly 

samplings. Xanthidae zoea, of which 750 were tested, had 24 hr latent 

survivability of 90% and 48 hr latent survivability of 85%. There was no 

apparent difference between day/night or monthly samplings. Pinnotheridae zoea 

exhibited 24 hr latent survivability of 86% and 74% for 48 hr latent 

survivability. Again, there was no apparent difference in latent survivability 

between day/night or monthly samplincjs. blegalops were not collected in 

sufficient numbers for detailed analysis. 

4.4. Survivability Comparisons Between Sites 

Table 12 summarizes survivability data for the abundant taxa at the three 

sampling sites. Though not statistically significant, engraulid and sciaenid 

eggs exhibited lower survival rates in comparison to control organisms’ 

survivability. Fish larval and zoea1 survivability were similar at all three .. .

sites. 

4.5. Survivability and Abiotic Parameters 

The mean values for abiotic parameters measured March through September 

are summarized in Table 2. Mean temperatures ranged from a low of 22.2 OC to a 

high of 32.5 OC. There was a correlation found between survivability and 

temperature in the prototype study, though the correlation was not a strong one. 

t 

t In this study, the temperatures followed a typical seasonal trend, and there was

no significant correlation between temperature and survivability. Salinity and 
Table 12. Comparison of percent initial and latent (48 hrs) survival of 

selected taxa between sampling sites at Big Bend Power Station. 

Control Screenwash ORD 

Taxa Initial Latent Initial Latent Initial Latent 

EGGS: 

Engraul idae 72 51 48 45 29 44 

Sciaenidae 72 56 63 44 56 47 

FISH LARVAE: 

Engraul idae 16 59 16 68 58 65 

Sciaenidae 85 61 61 63 56 66 

ZOEA: 

Caridea 65 88 72 67 70 66 

Xanthidae 88 85 93 80 90 71 

Pinnatheridae 77 74 89 71 83 65 

28 
-- -- 

-- -- 

-- -- 

-- 

Table 13. ,,dtcha, labySummary for FMS Survivability study stations. 

SCREENWASH STATION 

(n> DAY* (n) NI GHT" 

C1upeidae 6 0.83 + .289 5 0.71 -+ .057 

Engraul idae 1299 0.82 7 .097 562 0.66 7 -442 

Sciaenidae 1129 0.84 z .198 1416 0.76 T .042 

Soleidae 815 0.99 .006 64 0.93 T- .145 

ORGANISM RETURN DISCHARGE STATION 

(n> DAY (n> NIGHT 

C1,upei dae 2 

Engrauli dae 1140 0.91 + -043 219 0.95 -

+ .062 

Sciaenidae 88 1 0.90 T .082 1014 0.71 + .076 

Soleidae 817 0.99 .006 60 0.92 T- -098 

CONTROL STATION 

NIGHT 

C1upeidae 5 0.80 + .192 

Engraulidae 988 0.98 -+ -018 398 0.99 z .015 

Sciaenidae 357 0.92 2 -038 555 0.89 + .on 

Soleidae 4 0.80 - -320 

(n) = Number of organisms tested 

Mean Survival (percent: multiply by 100) 5 Standard Deviation 

29 

59-
I 

1 

I 

dissolved oxygen followed expected seasonal trends, with no correlation between 

survivabili ty and these parameters. 

4.6. Survivability Comparisons to Prototype Study 

A comparison of initial survival for selected taxa during the prototype 

and the FMS Survivability studies is given in Table 14. The initial survival of 

abundant eggs was similar in both studies, with differences being species 

specific. Fish larvae had a significantly lower survival during the prototype 

study, which may be attributed to differences in the sampling techniques between 

the two studies. Fish larvae survival was species specific in both studies. 

The initial survival of the invertebrates was higher in the prototype study than 

in the FMS Survivability study. These differences were species specific, with 

some variability seen between stations and species. 

A comparison of fish egg hatchability and latent 48 hour survival for 

selected taxa collected during the prototype and FMS Survivability FMS studies 

is given in Table 15. In general, hatchabiiity was high during the FMS 

Survivability study, as predicted during the prototype studies. Latent survival 

of fish larvae was low during the prototype study, and significantly higher 

during the FMS Survivability study. These results follow those obtained for the 

initial survival of fish larvae, and can be explained by the differences in the 

sampling techniques. The latent survival of the invertebrates was the highest 

of any organisms tested during both studies. In general, the latent survival 

was slightly lower during the FMS Survivability study, with variations seen .. .

between species and stations. 

5.0 DISCUSSION 

5.1 Overall SurviVal 

Results of this study indicate that of all the taxonomic groups studied, 

the invertebrates had the highest survival. Among invertebrates, the megalops 

stages exhibited the best survival rates. Fish larvae had low survivability 

especially fragile fish, such as many of the Engraulidae (anchovies). 

.. 

30 
Table 14. 

Fish Eggs:

Anchoa mitchilli 

Sci aenidae 

Fish Larvae: 

Anchoa mitchilli 

Sciaenidae 

Invertebrates: 

Caridea 

Xant h i dae 

Pi nnotheridae 

Comparison of initial survival (%) for selected 

taxa during the prototype and FMS Survivability

studies. 

Prototype FMS Survivability Study

Screenwash Screenwash ORD Ccntrol 

43 

75 

2 

19 

94 

99 

100 

48 29 72 

63 40 72 

16 58 16 

61 56 85 

72 70 65 

93 90 88 

99 a3 77 

31 
1 

f 

t 

i 

Table 15. 

-Taxa 

Fish Eggs:

Anchoa mitchilli 

Sciaenidae 

Fish Larvae: 

Anchoa mitchilli 

Sciaenidae 

Invertebrates: 

Caridea 

Xanthi dae 

Pinnotheridae 

Comparison of fish egg hatchability and latent 48 

hour survival (%)for selected taxa during the 

prototype and FMS Survivability studies. 

HATCHABILITY 

Prototvpe FMS Survivabilitv Study

Screenwash Screenwash ORD Control 

80 74 93 98 

95 80 80 90 

LATENT 48-HOUR SURVIVAL 

22 68 65 59 

11 63 66 61 

85 67 65 88 

96 

92 

80 71 

71 65 

85 

74 
The proportion of organisms a1 ive at 24 hrs and 48 hrs was used as a 

measure of latent survival. Results indicated that invertebrates had the 

highest latent survival , with fish larvae having a lower latent survivability. 

Initial survivability as well as hatchability of eggs was determined. 

Hatchability is a measure of the viability of the eggs. Egg survival was 

relatively low, but hatchability of those surviving eggs was high. 

5.2 Effectivenes of FMS 

The effectiveness of the fine mesh screens was determined by comparing 

survivability of eggs and larvae collected from the screenwash, organism return 

discharge (ORD), and control stations. Results of the testing showed a lowetinitial and latent survivability cjf organisms from the ORD station than either 

the screenwash or control stations. However, comparing results of the control 

testing and screenwash testing indicates that natural mortal ity not associated 

with the fine mesh screens may be a factor contributing to the mortalities 

observed among organisms collected by the fine mesh screens. Results also 

indicate that survivability is species and lifestage speciffc. This includes 

initial as well as latent survivability. There was no apparent difference in 

survivability between day and night samples, and no.difference in survivability 

between months. 

5.3 Comparison to Prototype 

Results obtained during this study were comparable to preliminary results 

obtained in the prototype study (TEC, 1980b). The initial.-survivabilityof eggs 

reported in this study were slightly higher than those reported in the prototype 

study, though hatchability was very similar. . The initial and latent 

survivability of fish reported in the prototype study was very low compared to 

what was reported in this study. Results obtained in this study for the control 

station were similar, though higher, to the control survivability values in the 

prototype study, but screenwash arid ORD survivability values were significantly 

higher than in the prototype. The high survivability of invertebrate stages was 

comparable in both the studies. In general, results obtained during the 

33 
full-scale study were equal to those predicted in the prototype study. In some 

cases, results obtained exceeded those expected, with these differences being 

attributed to differences in sampling techniques (i.e., nets in the FMS 

Survivability study versus sampling boxes in the Prototype study). 

34 
6.0 Summarv and Conclusions 

1. A Fine Mesh Screen (FMS) study was conducted from March 

through September, 1985 representing one full spawning season, after 

Unit 4 began commercial operation (February 25, 1985), to evaluate 

the effectiveness of FMS in reducing entrainment. 

2. Sampling was conducted at three stations: The screenwash in front 

of the screens, the end of the Organism Return Discharge (ORD),

and in the intake canal. Methods used were similar to those used 

during the FMS Prototype study conducted in !980 (TEC, 1980b). 

3. Certain species which are found in high abundance or are of 

commercial or forage value were targeted as Representative Important

Species (RIS) for this study, and initial and latent survivability of 

these taxa were analyzed for the screenwash, organism return 

discharge, and control stations. 

4. Initial survivability of Anchoa mitchilli eggs from the screenwash 

was 48%; from the ORD 29%; and from the control 72%. 

5. Initial survivability of Sciaenidae eggs from the screenwash was 63%,

from the ORD 40%, and from the control 72%. 

6. Initial survivability of select invertebrates from the screenwash was 

87%, from the ORD 85%, and from the control 80%. 

7. Initial survivability of Anchoa mitchilli larvae from the screenwash 

was 16%, from the ORD 58%, and from the control 16%. 

8. Initial survivability of Sciaenidae larvae from the screenwash wa: 

61%, from the ORD 56%, and from the control 85%. 

9. Hatchability of Anchoa mitchilli eggs from the screenwash was 74%, .. - from the ORD 81X, and from the control 99%. 

10. Hatchability of Sciaenidae eggs from the screenwash was 80%, from the 

ORD 81%, and from the control 91%. 

11. Latent survivability (48 hr) of Anchoa rnitchilli larvae from the 

screenwash was 68%, from the ORD 65%, and from the control 59%. 

12. Latent survivability (48 hr) of Sciaenidae larvae from the screenwash 

was 63%, from the ORD 66%, and from the control 61%. 

13. Latent survivability (48 hr) of select invertebrate larvae from the 

screenwash was 73%, from the ORD 67%, and from the control 82%. 

14. There was no correlation found betwesn abiotic parameters measured 

and survivabi1ity. 

35 
15. Initial survivability and hatchability of eggs in the FMS 

Survivability Study was comparable to initial survivability values 

reported in the prototype study conducted during 1980. 

16. Initial and latent survivability of fish eggs and larvae in the FMS 

Survivability Study was significantly higher than values reported in 

the prototype study. These differences are attributed to 

differences in sampling technique. 

17. Latent survivability of invertebrate larvae in the FMS Survivability

Study was comparable to values reported in the prototype study. 

18. Results indicate that survivablity is species and 1 ifestage specific. 

19. There was no significant difference in survival rates between 

stations. 

20. Survival rates during the FMS Survivability Study were generally as 

predicted by the prototype study, and in some cases exceeded 

predicted Val ues. 

H 

f 

36 

I 
7.0 LITERATURE CITED 

Tampa Electric Company, 1980a. 316(a) and (b) Demonstration, Big Bend 

Station - Unit 4, Tampa Electric Company (August 1980). Prepared by

Stone and Webster Engineering Corporation. 

Tampa Electric Company, 1980b. 316(a) and (b) Demonstration, Big Bend 

Station - Unit 4, Tampa Electric Company, Fine Mesh Screen Study

Report (November 1980). Prepared by Stone and Webster Engineering

Corporation. 

i 

i 

37 
I 

APPENDIX A 

FMS SURVIVABILITY STUDIES DATA 

SCREENWASH STATION 

f 
-- -- -- 

-- -- -- -- -- -- 

-- 

-- -- -- 

-- -- -- -- -- -- 

3 

Table A-1. Initial survival and hatchability of fish eggs, Screenwash Station, 

Big Bend Power Plant, for March 1985, day and night sampling. (1.00 = 100% survi Val and hatchabi 1i ty) .

f -

DAY

CLUPE IDAE 

ENGRAULIDAE 

SCIAENIDAE 

SOLEIDAE 

NIGHT 

CLUPEIDAE 

ENGRAULIDAE 

SCIAENIDAE 

SOLEIDAE. 

-

No. Initial 

Organ i sms - Survi Val Total 

Tested X S.D. No. 

97 0.98 0.03 

2314 0.60 0.29 205 

961 0.70 0.34 178 

No. Initial 

Organisms Survival Tot a1 

Tested X S.D. No. 

116 0.62 0.00 

-Hatchability 

X S.D. 

0.78 0.28 

0.83 0.30 

Hatchabi 1 i t y -

X S.D. 

2278 0.67 0.31 201 ..0 ..84 0.23 

4572 0.69 0.32 239 0.78 0.12 

-X = Mean survival (percent: multiply by 100). 

S.D. = Standard deviation. 
-- 

-- -- -- 

-- -- -- 

-- 

Table A-2. Initial survival and hatchability of fish eggs, Screenwash Station,

'Big Bend Power Plant, for April 1985, day and night sampling. (1.00 

= 100% survival and hatchability).

APRIL 

-

DAY

No. Initial 

Organisms - Survival Total 

Tested X S.D. No. 

ENGRAULIDAE 7838 0.79 0.29 257 

SCIAENIDAE 1905 0.73 0.36 312 

SOLEIDAE 18 1.oo 0.00 

NIGHT 

No. Initial 

Organi sms 

Tested - Survival 

X S.D 

Total 

No. 

CLUPEIDAE 1 1.oo 0.00 

Hatchability 

X S.D. 

0.89 0.22 

0.90 0:28 

-Hatchabil i ty 

X S.D 

ENGRAULIDAE 3411 0.67 0.30 324 - 0,81 0.15 

SCIAENIDAE 24332 0.82 0.12 269 0.76 0.22 

SOLEIDAE 1 1.oo 0.00 35 0.97 

-

-X = Mean survival (percent: multiply by 100).

S.D. = Standard deviation. 
-- 

-- -- -- -- 

-- -- 

-- -- -- -- 

Table A-3. Initial survival and hatchability of fish eggs, Screenwash Station,

Big Bend Power Plant, for Hay 1985, day and night sampling. (1.00 = 

100% survival and hatchability). 

-

DAY

CLUPEIDAE 

ENGRAULIDAE 

SCIAENIDAE 

SOLEIDAE 

NIGHT 

CLUPEI DAE 

ENGRAULIDAE 

SCIAENI DAE 

SOLEIDAE 

-

-

MAY

No. Initia1 

Organi srns 

Tested - Survival 

X S.D. 

Total 

No. -

Hatchabi1 i ty 

X S.D. 

2 0.50 0.71 2 0.50 0.71 

2261 0.81 0.23 21 1 0.64 0.11 

2056 0.64 0.39 208 0.40 0.36 

8 1.00 0.00 87 1.oo 

No. Initial 

Organi srns - SurviVal Total -

Hatchability

Tested X S.D. No. X S.D. 

3 0.75 

41 0.18 0.32 54 1 .. ­

7628 0.83 0.16 184 0.82 0.15 

9 1.00 

-X = Mean survival (percent: multiply by 100).

S.D. = Standard deviation. 

i 
-- 

-- -- -- -- 

-- -- -- 

-- -- -- -- 

Table A-4. Initial survival and'hatchability of fish eggs, Screenwash Station,

f

li 

Big Bend Power Plant, for June 1985, day and night sampling. (1.00 

= 100% survival and hatchability). 

JUNE 

-

DAY

No. Initia1 

Organisms

Tested - Survival 

X S.D. 

Total 

No. 

CLUPEIDAE 1 1.oo 0.00 1 

ENGRAULIDAE 89 0.90 0.05 102 

SCIAENIDAE 1503 0.57 0.46 105 

SOLEIDAE 136 

NIGHT 

No. Initia1 

Organisms ' - Survival Total 

Tested X S.D. No. 

ENGRAULIDAE 9 0.00 0.00 

-Hatchability 

X S.D. 

3 .oo 

0.85 3.34 

0.96 0.09 

0.99 

-Hatchability 

X S.D.­

.. -

SCIAENIDAE 4399 0.64 0.28 183 0.78 0.14 

SOL EIDAE. 6 1-00 

-

-X = Mean survival (percent: multiply by 100).

S.D. = Standard deviation. 

f 

Y.4 
-- 

-- 

-- -- -- -- 

-- -- -- 

-- -- -- -- 

Table A-5. Initial survival and hatchability of fish eggs, Screenwash Station, 

Big Bend Power Plant, for July 1985, day and night sampling. (1.00 = 100% surviVal and hatchabi 1 i ty) . 

JULY 

-

DAY

No. Initial 

Organisms - SurviVal Total -Hatchability

Tested X S.D. No. X S.D. 

CLUPEIDAE 2 0.50 0.71 3 1-00 

ENGRAULIDAE 1174 0.80 0.27 231 0.93 0.32 

SCIAENIDAE 168 0.68 0.39 121. 0.94 0.29 

SOLEIDAE 1 1.oo 0.00 237 0.99 

NIGHT 

No. Initial 

Organi snis - Survival Total -Hatchability

Tested X S.D. No. X S.D. 

CLUPEIDAE 2 0.67 

ENGRAULIDAE 4 0.00 0.00 .. . 

SCIAENIDAE 1150 0.57 0.21 178 0.73 0.13 

SOLEIDAE -2 0.67 

-

-X = Mean survival (percent: mu1tiply by 100).

S.D. = Standard deviation. 
-- -- -- -- -- -- 

-- -- -- -- 

-- 

-- -- -- -- -- -- 

-- 

-- -- -- -- -- -- 

Table A-6. Initial survival and hatchability of fish eggs, Screenwash Station,

Big Bend Power Plant, for August 1985, day and night sampling. (1.00

I = 100% survival and hatchability).

a AUGUST 

-

DAY

No. Initial 

Organi sms - Survival Total 

Tested X S.D. No. 

1 

CLUPEIDAE 

ENGRAULIDAE 1741 0.78 0.25 139 

SCIAENIDAE 178 0.64 0.34 51 

SOLEIDAE 255 

NIGHT 

No. Initial 

Organisms -

X 

SurviVal 

S.D. 

Total 

Tested No. 

CLUPEIDAE 

-Hatchability 

X S.D. 

0.82 0.10 

0.89 0.33 

0.99 

Hatchabi1i ty -

X S.D. -

ENGRAULIDAE 13 0.00 0.00 2 ..o.DO 

SCIAENIDAE 2259 0.76 0.14 164 0.69 0.21 

SOLEIDAE 

-

-X = Mean survival (percent: multiply by 100).

S.D. = Standard deviation. 

L/ 9 
-- -- -- -- -- -- 

-- 

-- -- -- -- -- -- 

-- 

-- -- -- -- 

Table A-7. Initial survival and hatchability of fish eggs, Screenwash Station,

Big Bend Power Plant, for September 1985, day and night sampling.

(1.00 = 100% survival and hatchability).

SEPTEMBER 

-

DAY

No. Initial 

Organisms - SurviVal Total 

Tested X S.D. No. 

CLUPEIDAE 

ENGRAULIDAE 714 0.46 0.43 190 

SCIAENIDAE . 16 0.33 0.58 154 

SOLEIDAE 1 0.00 0.00 100 

NIGHT 

No. Initia7 

Organisms - SurviVal Tota1 

Tested X S.D. No. 

CLUPEIDAE 

-Hatchability 

X S.D. 

0.81 0.21 

0.95 0.33 

1.oo 

-Hatchability 

X S.D. 

ENGRAULIDAE 11 0.04 0.08 35 ..o .97 

SCIAENIDAE 75 0.24 0.33 199 0.78 0.16 

SOLEIDAE 12 1.oo 

-

X = Mean survival (percent: multiply by 100). -

S.D. = Standard deviation. 
-- 

-- -- -- 

Table A-8. Initial survival of fish larvae from Big Bend Screenwash Station, 

day and night sampling, March 1985. (1.00 = 100% survival). 

INITIAL SURVIVAL 

DAY NIGHT 

No. No. 

Organisms Organisms -. - Taxa Tested X S.D. Tested X S.D. 

Cl upeidae 

Engraul idae 

Atherinidae 

Sparidae 

Lagodon

rhomboides 

Sciaenidae 

Bairdiell a 

chry sou ra 

Poqoni as 

cromi s 

Cynosci on 

nebul osus 

Cynosci on 

arenari us 

Leiostomus , xanthurus .. -.-

Blenniidae I 0.00 0.00 

Gobi idae 35 0.00 0.00 

Sol eidae 

-

-X = .Mean survival (percent: multiply by 100).

S.D. = Standard deviation. 

4 
-- -- -- 

Table A-9. Initial survival of fish larvae from Big Bend Screenwash Station,

day and night sampling, April 1985. (1.00 = 100% survival). 

Taxa 

Engraul idae 

Sciaenidae 

Bairdiell a 

c hrysoura 

Gobi idae 

-

INITIAL SURVIVAL 

DAY NIGHT 

No. No. 

Organisms - Organisms - Tested X S.D. Tested X S.D. 

202 0.33 0.58 224 0.23 0.39 

416 0.81 0.20 42 0.94 0.13 

1 0.00 0.00 

4 0.00 0.00 

-X = Mean survival (percent: multiply by 100).

S.D. = Standard deviation. 
-- -- -- -- -- -- 

-- -- -- -- -- -- 

-- -- -- 

Table A-30. Initial survival of fish larvae from Big Bend Screenwash Station, 

day and night sampling, May 1985. (1.00 = 100% survival). 

INITIAL SURVIVAL 

DAY NIGHT 

No. No. 

Taxa 

Organisms

Tested - Organisms 

X S.D. Tested -X S.D. 

C1 upeidae 

Engraul i dae 124 0.00 0.00 125 0.00 0.00 

Atherinidae 

Sparidae 1 O.OG 0.00 

Sciaenidae 973 0.79 0.34 51 0.00 0.00 

Bairdiell a 

ch ry sou ra 1 0.00 0.00 

Cynosci on 

nebul osus 

Cynosci on 

arenari us 2 0.00 0.00 

f 

Gobi idae 9 0.00 0.00 7 0.00 0.00 

-

-X = Mean survival (percent: multiply by 100).

S.D. = Standard deviation. 

4 
-- 

-- -- -- -- 

Table A-11. Initial survival of fish larvae from Big Bend Screenwash Station, 

day and night sampling, June 1985. (1.00 = 100% survival). 

Taxa 

Engraul idae 

Laqodon

rhomboides 

Sciaenidae 

Bairdi el 1a 

chrysou r a 

Pogoni as 

cromi s 

Cynosci on 

nebul osus 

Cynosci on 

arenari us 

Lei ostomus 

xan thurus 

-

INITIAL SURVIVAL 

DAY NIGHT 

No. No. 

Organisms Organisms - - Tested X S.D. Tested X S.D. 

49 0.07 0.22 129 0.18 0.30 

55 0.96 0.06 6 0.00 0.00 

0.50 0.71 

0.39 0.34 

-X = Mean survival (percent: multiply by 100). 

S.D. = Standard deviation). 
1. 

1 

1 Table A-12. Initial survi a1 of fish larvae from Big Bend Screen\ ash St tion,

day and night sampling, July 1985. (1.00-= 100% survival). 

t INITIAL SURVIVAL 

DAY NIGHT 

No. No. 

Oraani sms - Orqan i sms - Taxa TGsted X S.D. TGsted X S.D. 1 

1 C1 upeidae 

Engraul idae 

1 At her i n i dae 

1 Sparidae 

Lagodon

rhomboides

f

1 Sciaenidae 

i Bairdiella 

ch ry sou ra 

Pogoni a s I cromi s 7 

Cynosci on 

nebul osus 1 

Cynosci on 

arenari us t Leiostomus 

xanthurus

i 

i Blenni idae 

1 Gobi idae 

Sol eidae 

i ­

-X = Mean survival (percent: multiply by 100). 

S.D. = Standard deviation. 

i 
-- 

-- 

Table A-13. Initial survival of fish larvae from Big Bend Screenwash Station, 

day and night sampling, August 1985. 

INITIAL SURVIVAL 

DAY 

No. 

Organisms - Taxa Tested X S.D. 

C1 upeidae 

Engraul idae 

Atheri nidae 

Spari dae 

Lagodon

rhomboi des 

Sciaenidae 

Bairdiell a 

ch ry sou ra 

Poqoni as 

cromi s 

Cynosci on 

nebul osus 

Cynosci on 

arenari us 

Leiostomus 

xanthurus 

Bl enni idae 

Gobi idae 

Sol eidae 

-

X = Mean survival (percent: multiply by 100). -

S.D. = Standard deviation. 

(1.00 = 100% survival). 

NIGHT 

No. 

Organisms - Tested X S.D. 

3 0.00 0.00 

.. -.­

0.25 

i 
Table A-14. Initial survival of fish larvae from Big Bend Screenwash Station, 

day and night sampling, September 1985. (1.00 = 100% survival). 

INITIAL SURVIVAL 

DAY NIGHT 

No. No. 

i Organi sms - Organisms - Taxa Tested X S.D. Tested X S.D. 

1

i Cl upeidae 

Engraul idae 

1 Atherinidae 

t Sparidae 

Lagodon

rhomboides

1 Sciaenidae 

F Bai rdi el 1a 

e chrysoura 

Poqoni as z 

f crorni s 

a 

Cynosci on 

* nebul osus B

; Cynosci on 

r arenari us 

Leiostomus 

xanthurus 

i’

i f3l enn i i dae 

1 Gobi idae 

Sol eidae 

I -

-X = Mean survival (percent: multiply by 100).

S.D. = Standard deviation. 

f 

i 

t 

i 
c 

-- -- -- -- -- -- 

-- -- -- 

-- -- -- 

I 

I 

I 

I 

1 

1 

1 

1 

\ 

f 

ii 

T 

f 

1

f 

1

i 

Table A-15. Initial survival of invertebrate larvae from Big Bend Screenwash 

Station, day and night sampling, March 1985. (1.00 = 100% 

survi Val ) . 

~ INITIAL SURVIVAL 

DAY NIGHT 

No. No. 

Taxa Organi sms Tested -X Organisms S.D. Tested -X S.D. 

ZOEA 

Penaei dae 

Cari dea 36 0.74 0.43 84 0.94 0.14 

Portunidae 15 1.oo 0.00 11 0.97 0.08 .. 

Paguridae 7 1.oo 0.00 19 0.91 0.27 

Xanthiidae 1069 0.98 0.05 1659 0.92 0.20 

Pinnotheridae 1858 0.99 0.03 650 0.85 0.31 

Grapsidae 1 1.00 0.00 

MEGALOPS 

Xant h i dae 8 1.oo 0.00 

JUVENILES 

Lo1 1iquncul a 

brevis 1 1.oo 0.00

-

X = Mean survival (percent: multiply by 100). -

S.D. = Standard deviation. 

' 
-- -- -- -- 

-- 

-- -- -- 

-- -- -- -- 

-- -- 

-- -- 

survi Val ) . 

INITIAL SURVIVAL 

DAY 

No. No. 

Organisms Organisms - Taxa Tested X S.D. Tested 

ZOEA 

Penaeidae 

1 ' Caridea 118 0.90 0.29 34 

3 Portunidae 5 1.oo 0.00 

1 Paguridae 20 1.00 0.00 1 

i Xanthiidae 2037 0.97 0.08 217 

Pinnotheridae 1317 0.99 0.02 151 

4 Grapsidae 40 1.oo 0.00 3 

z 

MEGALOPS r Xanthi dae 1 

I

f Grapsi dae 4 1.00 0.00 6 

JUVENILES 

Lo1 1iquncul a 

brevis 

-

-x = Mean survival (percent: multiply by 100). 

S.D. = Standard deviation. 

f 

Table A-16. Initial survival of invertebrate larvae from Big Bend Screenwash 

Station, day and night sampling, April 1985. (1.00 = 100%

NIGHT 

-

X S.D. 

0.67 0.41 

1-00 0.00 

0.96 ' 0.13 

0.93 0.17 

0.67 0.58 

1.00 0.00 

1-00 0.00 
-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

Table A-17. Initial survival of invertebrate larvae from Big Bend Screenwash 

Station, day and night sampling, May 1985. (1.00 = 100% survival). 

INITIAL SURVIVAL 

DAY NIGHT 

No. No. 

Taxa 

Organisms 

Tested -

X Organ i sms S.D. Tested -X S.D. 

ZOEA 

Penaeidae 

Caridea 

Portunidae 

Paguri dae 

Xanthiidae 

Pinnotheridae 

Grapsi dae 

MEGALOPS 

Xanthi dae 

Graps idae 

JUVENILES 

Lo1 1i guncul a 

brevis 

-

3 23 0.87 0.27 0.89 0.28 

20 1.oo 0.00 

1538 0.98 0.04 0.95 0.18 

2459 0.86 0.32 0.80 0.32 

113 0.99 0.04 1.00 0.00 

8 1.oo 1.00 0.67 0.58 

37 0.83 0.41 .0.50 0.50 

-X = Mean survival (percent: multiply by 100). 

S.D. = Standard deviation. 
-- -- -- -- -- -- 

-- -- 

-- -- 

-- -- -- 

-- -- -- 

Table A-18. Initial survival of invertebrate larvae from Big Bend Screenwash 

Station, day and night sampling, June 1985. (1.00 = 100% survival). 

DAY . 

No. 

Organ i sms - Taxa Tested X 

ZOEA 

Penaei dae 

Caridea 83 0.78 

Portuni dae 

Paguridae 1 1.oo 

Xanthiidae 1031 0.95 

Pinnotheridae 2655 0.99 

Grapsidae 168 1.00 

MEGALOPS 

Xant hi dae 1 1.oo 

Graps idae 7 1.oo 

JUVENILES 

Lo1 1iquncul a 

brevis 

-

INITIAL SURVIVAL 

N IGHT 

No. 

Organisms - S.D. Tested X S.D. 

0.37 37 0.62 0.46 

0.00 

0.16 343 0-82 0.33 

0.02 658 0.79 0.34 

0.00 

0.00 1 0.00 0.00 

0.00 1 1.00 0.00 

-X = Mean survival (percent: multiply by 100).

S.D. = Standard deviation. 

I 
-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- -- 

-- -- 

Table A-19. Initial survival of invertebrate larvae from Big Bend Screenwash 

Station, day and night sampling, July 1985. (1.00 = 100% survival). 

INITIAL SURVIVAL 

DAY NIGHT 

No. No. 

Taxa Organisms Tested -X S.D. 

Organisms

Tested -

X S.D. 

ZOEA 

Penaei dae 

Caridea 

Portunidae 

Paguridae 

Xanthiidae 

Pi nnotheri dae 

Grapsidae 

MEGALOPS 

Xant hi dae 

Graps i dae 

JUVENILES 

Lo1 1i guncul a 

brevis 

-

1 1-00 0.00 

99 0.49 0.44 54 0.35 0.39 

3 0.67 0.58 

2 1-00 0.00 

725 0.90 0.16 169 0.74 0.36 

5402 0.85 0.27 1184 0.73 0.34 

59 0.85 0.33 35 0.75 0.50 

1 1.oo 0.00 1 1.oo 0.00 

4 1.00 0.00 1 0.00 0.00 

-X = Mean survival (percent: multiply by 100). 

S.D. = Standard deviation. 
-- -- -- -- -- -- 

-- -- -- 

-- -- -- -- -- 

Table A-20. Initial survival of invertebrate larvae from Big Bend Screenwash 

Station, day and night sampling, August 1985. (1.00 = 100% 

survival). 

INITIAL SURVIVAL 

DAY NIGHT 

No. No. 

Taxa 

Organ i sms

Tested -

X S.D. 

Organisms

Tested -

X S.D. 

ZOEA 

Penaeidae 

Caridea 47 0.43 0.43 79 0.62 0.42 

Portunidae 1 1.oo 0.00 

Paguridae 4 1.00 0.00 2 1.00 0.00 

Xanthiidae 957 0.97 0.07 428 0.95 0.07 

Pinnotheridae 3916 0.91 0.24 2615 0.81 0.35 

Grapsidae 15 0.95 0.11 26 0.93 0.19 

MEGALOPS 

Xanthidae 1 0.00 0.OCI 

Grapsidae 45 1.00 0.00 33 0.57 0.49 

JUVENILES 

Lolliguncula --. brevis .. ­

- = Mean survival (percent: multiply by 100). -

S.D. = Standard deviation. 

X 
-- 

-- -- -- -- -- -- 

-- -- -- 

Table A-21. Initial survival of invertebrate larvae from Big Bend Screenwash 

Station, day and night sampling, September 1985. (1.00 = 100% 

survival). 

Taxa 

ZOEA 

Penaeidae 

Cari dea 

Portunidae 

Pag ur idae 

Xanthiidae 

Pinnotheridae 

Grapsi dae 

Grapsidae 

JUVENILES 

Lo11i guncul a

brevi s 

-

IN IT IAL SURVI VAL 

DAY NIGHT 

No. No. 

Organisms - Organisms - Tested X S.D. Tested X S.D. 

3 1.00 0.00 2 1-00 0.00 

5 0.75 0.35 9 1.oo 0.00 

4 0.50 0.71 1 1.oo 0.00 

521 0.94 0.17 371 0.98 0.05 

6303 0.91 0.21 3861 0.99 0.02 

18 1.00 0.00 19 1.oo 0.00 

1 1.oo 0.00 

.. . 

-

X = Mean survival (percent: multiply by 100).

S.D. = Standard deviation. 

c 
-- -- -- -- 

-- 

-- -- -- -- -- 

-- -- -- -- -- 

-- -- -- -- -- -- -- 

Table A-22. Latent survival of hatched fish larvae from Big Bend Screenwash 

Station for 24 and 48 hours, day and night sampling, March 1985. 

(1.00 = 100% survival). 

i

i Taxa 

Cl upeidae 

Engraul idae 

Atheri ni dae 

Sparidae 

Lagodon

rhomboides 

Sciaenidae 

Bai rdi el 1a 

ch ry soura 

Pogoni as 

cromi s 

Cynosci on 

nebul osus 

B1 enni i dae 

Gobi idae 

-

LATENT SURVIVAL 

DAY NIGHT 

No. No. 

Organisms 24 hrs 48 hrs Organisms 24 hrs 48 hrs 

Tested TI S.D. ST S.D. Tested X S.D. TT S.D. 

3 1.00 1.00 9 1.00 1.00 

147 

2 0.75 0.35 0.75 0.35 

142 0.96 0.07 0.85 0.18 168 1.00 0.00 0.92 0.09 

3 1-00 0.00 1.00 0.00 

4 0.75 0.35 0.75 0.35 3 0.75 0.35 0.75 0.35 

1 1.00 1.00 

-X = Mean survival (percent: mu1 ti ply by 100). 

S.D. .= Standard deviation. 
-- -- -- -- -- 

-- -- -- -- -- 

-- -- -- -- -- 

i 

i 

?

E 

T 

Table A-23. Latent survival of hatched fish larvae ,from Big Bend Screenwash 

Station for 24 and 48 hours, day and night sampling, April 1985. 

(1.00 = 100% survival). 

LATENT SURVIVAL 

DAY NIGHT 

No. No. 

Organisms 24 hrs 48 hrs Organisms 24 hrs 48 hrs 

Taxa Tested 5? S.D. iT S.D. Tested Y S.D. X S.D. 

Cl upeidae 5 0.00 0.00 0.00 0.00 

Engraul idae 225 0.94 0.15 0.88 0.21 251 0.91 0.25 0.84 0.27 

Atherinidae 1 0.00 0.00 0.00 0.00 

Lagodon

rhornboides 

Sci aenidae 279 0.77 0.26 0.73 0.29 178 0.83 0.32 0.72 0.33 

Bai rdi el 1a 

ch rysour a 3 1.00 0.00 1.00 0.00 

Poqoni as 

crorni s 1 1.00 0.00 1.00 0.00 3 1.00 0.00 1.00 0.00 

Gobi idae 1 0.00 0.00 0.00 0.00 7 . 0.62 0.47 0.6.2 0.47 

Sol eidae 67 0.98 0.03 1.00 0.00 33 1.00 0.00 0.96 0.05 

-

-X = Mean survival (percent: multiply by 100).

S.D. = Standard deviation. 
-- -- -- -- -- 

-- -- -- -- -- 

-- -- -- -- -- 

-- -- -- -- -- 

Table A-24. Latent survival of hatched fish larvae from Big Bend Screenwash 

Station for 24 and 48 hours, day and night sampling, May 1985. 

(1.00 = 100% survival). 

LATENT SURVIVAL 

DAY NIGHT 

No. No. 

Organisms 24 hrs 48 hrs Organisms 24 hrs 48 hrs 

Taxa Tested F Tested Y X 

I 

1 

1 

I 

I 

1 

a

I 

Y 

4 

F 

i

I 

z 

ii 

1 

f 

t 

1 

t

! 

1 

i 

TT S.D. S.D. 

C1 upeidae 

Engraul idae 197 0.69 0.48 0.60 0.49 

Sciaenidae 185 0.69 0.40 0.46 0.41 

Cynoscion

nebul osus 1 0.00 0.00 0.00 0.00 

Cynosci on 

arenari us 7 0.83 0.24 0.67 0.47 

Lei ostornus 

xanthurus 

Soleidae 87 0.92 0.19 0.88 0.31 

-

-X = Mean survival (percent: multiply by 100). 

S.D. = Standard deviation. 

S.D. S.D. 

2 1.00 0.00 0.00 0.00 

541 0.90 0.20 0.83 0.23 

133 0.80 0.35 0.55 0.35 

2 0.50 0.71 0.50 0.7:i. 

9 1.00 0.00 1.00 0.00 

-. ­

2 1.00 0.00 1.00 0.00 

3. 0.67 0.58 0.67 0.58 

9 1.00 0.00 1.00 0.00 

i 

t 

i 
-- -- -- -- 

-- -- -- -- 

-- -- -- -- -- 

-- -- -- -- -- 

-- -- -- -- -- 

Table A-25. Latent survival of hatched fish larvae from Big Bend Screenwash 

Station for 24 and 48 hours, day and night sampling, June 1985. 

(1.00 = 100% survival). 

4 

LATENT SURVIVAL 

DAY NIGHT 

No. ' No. 

Organisms 24 hrs 48 hrs Organisms 24 hrs 48 hrs 

Taxa Tested j? S.D. TT S.D. Tested F S.D. 'ii S.D. 

f C1 upei dae 1 0.00 0.00 0.00 0.00 -_. 

Engraul idae 90 0.78 0.44 0.62 0.47 -_ 

1 

Sci aeni dae 101 0.75 0.38 0.44 0.47 119 0.84 0.30 0.77 0.42 

Pogonias

cromi s 

Cynoscion

nebul osus 

Cynosci on 

arenari us 

Leiostomus 

xanthurus 

Blenni idae 1 0.00 0.00 0.00 0.00 

Gobiidae 1 - 1.00 0.00 1.00 0.00 

Soleidae 135 0.88 0.35 0.83 0.36 6 1.00 0.00 1.00 0.00 

-

-X = Mean survival (percent: multiply by 100). 

S.D. = Standard deviation. 

t 
-- -- -- -- -- 

-- -- -- -- -- 

-- -- -- -- -- 

-- -- -- -- -- 

Table A-26. Latent survival of hatched fish larvae from Big Bend Screenwash 

Station for 24 and 48 hours, day and night sampling, July 1985. 

(1.00 = 100% survival).

LATENT SURVIVAL 

DAY 

No. 

Organisms 24 hrs 48 hrs 

Tested 'iT S.D. P S.D. 

7 1.00 0.00 0.66 0.00 

113 0.60 0.52 0.57 0.49 

236 1.00 0.00 0.92 0.29 

NIGHT 

24 hrs 48 hrs 

S.D. 32 S.D. 

0.00 0.00 0.00 

No. 

Organisms

Taxa Tested 1

C1upeidae 

Engraul i dae 

Atherinidae 

Sparidae 

Lagodon

rnomboides 

Sciaenidae 

Bairdiel1a 

chrysoura 

Pogonias 

cromis 

Cynoscion 

nebulosus 

Cynoscion 

arenari us 

Leiostomus 

xanthurus 

Blenniidae 

Gobiidae . 

Soleidae 

-

1 

2 

105 

9 

0.00 

1.00 0.00 1.00 0.00 

0.86 0.35 0.69 0.39 

0.72 0.26 0.72 0.26 

-X = Mean survival (percent: multiply by 100). 

S.'D. = Standard deviation. 
-- -- -- -- -- -- -- -- -- -- 

-- -- -- -- -- 

Table A-27. Latent survival of hatched fish larvae from Big Bend Screenwash 

Station for 24 and 48 hours, day and night sampling, August 1985. 

(1.00 = 100% survival). 

LATENT SURVIVAL 

DAY NIGHT 

No. No. 

OrganismsTT 24 hrs -

48 hrs Organisms 24 hrs -48 hrs 

Taxa Tested S.D. x S.D. Tested K S.D. x S.D. 

1 C1upeidae 

Engraul idae 191 0.89 0.33 0.76 0.43 1 0.00 0.00 0.00 0.00 

1 

1 

f Sciaenidae 43 0.62 0.51 0.45 0.41 61 0.77 0.34 0.40 0.45 

P Bairdiel1a 

i ch rysou ra 

Pogonias a

t cromis 

T 

Cynoscion 

nebulosus f Cynoscion

arenarius f 

f 

5 1.00 0.00 0.67 0.58 I Soleidae 252 0..95 0.16 0.94 0.16 4 1.00 0.00 1.00 0.00 

I 

j -

-X = Mean survival (percent: multiply by 100). 

S.D. = Standard deviation. 

*i 
-- -- -- -- -- -- -- -- -- -- 

-- -- -- -- -- -- -- -- -- -- 

-- -- -- -- -- 

-- -- -- -- -- 

Table A-28. Latent survival of hatched fish larvae from Big Bend Screenwash 

Station for 24 and 48 hours, day and night sampling, September

1985. (1.00= 100% survival). 

Taxa 

C1 upeidae 

Engraulidae 

Atherinidae 

Sparidae 

Laqodon

rhomboides 

Sciaenidae 

Bairdiel 1a 

chrysoura 

Poqonias

cromis 

Cynoscion 

nebulosus 

Cynoscion

arenarius 

Leiostomus 

xanthurus 

B1 enniidae 

Gobiidae 

Soleidae 

-

LATENT SURVIVAL 

DAY NIGHT 

No. No. 

Organisms 24 hrs 48 hrs Organisms 24 hrs 48 hrs 

Tested 5? S.D. F S.D. Tested 5? S.D. K S.D. 

150 0.82 0.38 0.68 0.43 75 0.65 0.43 0.57 0.40 

4 0.33 0.58 0.00 0.00 69 0.34 0.42 0.25 0.43 

.. . 

1 1.00 0.00 1.00 0.00 

21 0.41 0.43 0.31 0.43 

100 1.00 0.00 1.00 0.00 12 1.00 0.00 1.00 0.00 

-

X = Mean survival (percent: multiply by 100).

S.D. = Standard deviation. 
-- -- -- -- -- 

-- -- 

-- -- -- -- -- 

-- -- -- -- -- 

-- -- -- -- -- 

-- -- -- -- -- 

I 

Table A-29. 

Taxa 

C1upeidae 

Anchoa mitchilli 

Atherinidae 

Sparidae 

Lasodon rhomboides 

Sciaenidae 

Bairdiella chrysoura 

Poqonias cromis 

Cvnoscion nebulosus 

Cvnoscion arenarius 

Leiostomus xanthurus 

B1 enniidae 

Gobi idae 

Soleidae 

-

Summary of the latent survival of fish larvae from 

Big Bend Screenwash Station for 24 and 48 hours,

March 1985. (1.00 = 100% survival). 

24 hrs 48 hrs 

No. - - Tested X S.D. X S.D. 

1 1.oo 1.00 

3 1.oo 0.00 1.oo 0.00 

x = Mean survival (percent: multiply by 100)

S.D. = Standard deviation 

i 
-- 

-- 

-- 

-- 

-- -- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

Table A-30. 

Taxa 

Clupeidae 

Anchoa mitchilli 

Atherinidae 

Sparidae 

Laqodon rhomboides 

Sciaenidae 

Bairdiella chrvsoura 

Poqonias cromis 

Cvnoscion nebulosus 

Cvnoscion arenarius 

Leiostomus xanthurus 

B1enni idae 

Gobiidae 

Soleidae 

Anchoa sp. 

Summary of the latent survival of fish larvae from 

Big Bend Screenwash Station for 24 and 48 hours,

April 1985. (1.00 = 100% survival). 

24 hrs 48 hrs 

No. - Tested X 

0.00 

0.80 

1.oo 

0.88 

1.oo 

1.oo 

0.50 

5 0.50 

5 0.66 

1 1.00 

- S.D. X S.D. 

0.06 

0.28 0.79 0.27 

1.oo 

0.12 0.83 0.17 

0.00 1.00 0.00 

0.00 1.00 0.00 

0.71 0.50 0.71 

0.71 0.50 0.71 

0.58 0.66 0.58 

-

1.00 

TT = Mean survival (percent: multiply by 100)

S.D. = Standard deviation 

I/ 
-- -- -- -- -- 

-- -- -- -- -- 

-- -- -- -- -- 

-- -- -- -- -- 

-- -- -- -- -- 

-- -- -- -- -- 

-- -- 

-- -- -- -- -- 

-- -- -- -- -- 

Table A-31. 

Taxa 

C1 upeidae 

Anchoa mitchilli 

Atherinidae 

Sparidae 

Laqodon rhomboides 

Sciaenidae 

Bairdiella chrvsoura 

Poqonias cromis 

Cvnoscion nebulosus 

Cvnoscion arenarius 

Leiostomus xanthurus 

Bl enni i dae 

Gobiidae 

Soleidae 

Summary of the latent survival of fish larvae from 

Big Bend Screenwash Station for 24 and 48 hours,

May 1985. (1.00 = 100% survival). 

24 hrs 48 hrs 

No. ­ -

Tested X S.D. X S.D. 

8 1.00 0.00 1.oo 0.00 

66 0.80 0.22 0.53 0.36 

1 0.00 0.90 

16 0.70 0.41 0.60 0.42 

4 0.50 0.71 0.50 0.71 

4 1.00 0.00 ._1..oo 0.00 

X = Mean survival (percent: multiply by 100)

S.D. = Standard deviation 

f 

i 
Table A-32. 

Taxa 

Summary of the latent survival of fish larvae from 

Big Bend Screenwash Station for 24 and 48 hours, 

June 1985. (1.00 = 100% survival). . 

24 hrs 48 hrs 

No. - - Tested X S.D. X S.D. 

Clupeidae 

Anchoa rnitchilli 

Atheri nidae 

Sparidae 

Laqodon rhornboides 

Sciaenidae 

Bai rdiell a chrvsoura 

Poqonias crornis 

Cvnoscion nebulosus 

Cvnoscion arenarius 

Leiostomus xanthurus 

B1enni idae 

Gobi idae 

Sol eidae 8 1.00 

ST = Mean survival (percent: multiply by 100)

S.D. = Standard deviation 
-- 

-- 

-- -- 

-- -- 

-- 

-- 

-- 

-- -- 

Table A-33. 

Taxa 

Clupeidae 

Anchoa mitchilli 

Atherinidae 

Sparidae 

Lasodon rhomboides 

Sciaenidae 

Bairdiella chrvsoura 

Poaoni as cromi s 

Cynoscion nebulosus 

Cvnoscion arenarius 

Leiostomus xanthurus 

Blenni idae 

Gobi idae 

Sol eidae 

-

Summary of the latent survival of fish larvae from 

Big Bend Screenwash Station for 24 and 48 hours, 

July 1985. (1.00 = 100% survival). 

24 hrs 48 hrs 

No. - - Tested X S.D. X S.D. 

5 1.oo 0.00 1.oo 

30 0.93 0.12 0.87 

9 0.89 

1-00 0.00 0 ..87 0.25 

x = Mean survival (percent: multiply by 100)

S.D. = Standard deviation 
-- 

-- 

-- 

-- 

-- 

-- 

-- 

-- 

Table A-34. Summary of the latent survival of fish larvae from / Big Bend Screenwash Station for 24 and 48 hours, 

August 1985. (1.00 = 100% survival). 

No. 

Taxa Tested 

C1 upeidae 

Anchoa mitchilli 

Atherinidae 

Sparidae 

Laqodon rhomboides 

Sciaenidae 

Bai rdi el 1a chrvsoura 

Poqonias cromis 

Cvnoscion nebulosus 

Cvnoscion arenarius 

Leiostornus xanthurus 

B1 enni i dae 

Gobi idae 

Soleidae 3 

-

x = Mean survival (p rcent: multipl

S.D. = Standard deviation 

24 hrs 48 hrs 

- - X S.D. X S.D. 

0.00 

1.oo 

1-00 

0.51 

1-00 

1.oo 

by 100) 
-- -- -- -- 

-- -- 

-- -- 

-- -- 

-- -- 

-- -- 

-- -- 

-- -- 

-- 

-- 

E 

-- -- -- -- 

1 

I 

\ Table A-35. 

1 

I

i 

Taxa 

C1 upeidae 

Anchoa mitchilli 

Atheri ni dae 

Sparidae 

Laaodon rhomboides 

Sci aeni dae 

I 

Bairdiella chrvsoura 

Poaonias cromis 

Cvnoscion nebulosus 

-

* 

a. 

Cynoscion arenarius 

Leiostomus xanthurus 

�31enni idae 

Gobi idae 

Soleidae 

-

x = Mean survival (percent:

S.D. = Standard deviation 

Summary of the latent survival of fish larvae from 

Big Bend Screenwash Station for 24 and 48 hours, 

September 1985. (1.00 = 100% survival). 

24 hrs 48 hrs 

No. - - Tested X S.D. X S.D. 

10 0.75 0.50 0.66 

32 0.43 

53 0.49 0.42 

17 0.50 0.45 0.37 0.49 

10 0.70 0.45 0,70 0.45 

mu1ti ply by 100) 
-- -- -- -- -- -- -- -- -- -- 

Table A-36. Latent survival of invertebrate larvae from Big Bend Screenwash 

Station for 24 and 48 hours, day and night sampling, March 1985. ' 

(1.00 = 100% survival). 

LATENT SURVIVAL 

DAY NIGHT 

No. No. 

Organisms 24 hrs 48 hrs Organisms 24 hrs - 48 hr5 

Taxa Tested K S.D. r? S.D. Tested 7 S.D. x S.9,.-_ 

ZOEA 

Penaeidae 

Caridea 141 0.80 0.26 0.72 0.30 72 0.88 0.18 0.81 0.24 

Portunidae 1 1.00 0.00 0.00 0.00 2 0.75 0.35 0.25 0.35 

Paguridae 16 1.00 0.00 0.69 0.46 16 0.59 0.26 0.59 0.26 

-Xanthiidae 109 0.77 0.32 0.66 0.35 135 0.79 0.34 0.74 0.37 

Pinnotheridae 42 0.77 0.37 0.58 0.40 46 0.74 0.32 0.61 0.39 

Grapsidae 1 0.88 0.25 0.88 0.25 1 1.00 0.00 0.75 0.00 

MEGALOPS 

Xanthiidae 

Grapsidae 

JUVENILES 

Lo1 1iguncula 

brevis 2 0.00 0.00 0.00 0.00 2 0.00 "0.00 0.00 0.00 

-

-X = Mean survival (percent: multiply by 100). 

S.D. = Standard deviation. 
-- -- -- -- -- 

-- 

1 Table A-37. Latent survival of invertebrate larvae from Big Bend Screenwash 

Station for 24 and 48 hours, day and night sampling, April 1985. 

(1.00 = 100% survival). 1 

1 LATENT SURVIVAL 

DAY NIGHT 

7 ' NO. No. 

Organisms S.D. - 48 hrs Organisms 24 hrs 48 hrs 

Taxa Tested X 24 hrs 

x S.D. Tested TT S.D. -E S.D. 

Caridea 231 0.81 0.40 0.59 0.31 88 0.45 0.40 0.78 0.32 

Portunidae 1 1.00 0.00 1.00 0.00 

Paguridae 15 0.30 0.23 0.75 0.29 3 0.67 0.58 0.67 0.58 

Xanthiidae 159 0.75 0.31 0.63 0.38 125 0.90 0.26 0.89 0.26 

Pinnotheridae 79 0.38 0.29 0.71 0.27 98 0.90 0.16 0.79 0.20 

Grapsidae 2 1-00 0.00 1.00 0.00 4 1.00 0.00 0.75 0.50 

MEGALOPS 

Xanthiidae 18 1.00 0.00 1.00 0.00 3 1.00 0.00 1.00 0.00 

Grapsidae 52 -0.99 0.03 0.97 0.06 24 1.00 0.00 1.00 0.00 

JUVENILES 

Lo11iguncula 

brevis 13 0.22 0.40 0.22 0.40 13 0.80 0.20 0.00 0.00 

-

-

X = Mean survival- (percent: multiply by 100).

S.D. = Standard deviation. 
-- -- -- -- -- -- -- -- -- -- 

-- -- -- -- -- 

Table A-38. Latent survival of invertebrate larvae from Big Bend Screenwash 

Station for 24 and 48 hours, day and night sampling, May 1985. 

(1.00 = 100% survival). 

LATENT SURVIVAL 

Taxa 

ZOEA 

Penaeidae 

Caridea 

Portunidae 

Paguridae 

Xanthiidae 

Pinnotheridae 

Grapsidae 

MEGALOPS 

Xanthiidae 

Grapsidae 

JUVENILES 

Lo11i guncula 

brevis 

-

DAY 

No. 

Organisms 24 hrs 48 hrs 

Tested P S.D. ST S.D. 

198 0.70 0.28 0.59 0.28 

1 1.00 0.00 1.00 0.00 

6 0.60 0.54 0.60 0.54 

242 0.86 0.21 0.75 0.30 

76 0.87 0.16 0.76 0.26 

14 0.73 0.48 0.73 0.48 

53 1.00 0.00 0.99 0.02 

117 0.85 0.23 0.84 0.23 

5 0.00 0.00 0.00 0.00 

NIGHT 

No. 

Organisms 24 hrs - 48 hrs 

Tested W S.D. x S.D. 

146 0.74 0.34 0.68 0.35 

157 0.87 0.30 0.78 0.38 

126 0.86 0.19 0.71 0.29 

34 1.00 0.00 0.87 0.23 

45 0.97 0.05 0.86 0.21 

150 0.96 0.05 0.91 0.12 

3 0.00 -o..oo 0.00 0.00 

-X = Mean survival (percent: multiply by 100). 

S.D. = Standard deviation. 
-- -- -- -- -- -- -- -- -- -- 

-- -- -- -- -- 

-- -- -- -- -- 

3 

I 

t 

7 

1 

1 

i 

1 

Table A-39. Latent survival of invertebrate larvae from Big Bend Screenwash 

Station for 24 and 48 hours, day and night sampling, June 1985. 

(1.00 = 100% survival). 

LATENT SURVIVAL 

DAY NIGHT 

No. No. 

Organisms 24 hrs -48 hrs Organisms 24 hrs -48 hrs 

Taxa Tested Tc S.D. x S.D. Tested 7? S.D. x S,D. 

ZOEA 

Penaeidae 

Caridea 107 0.80 0.26 0.68 0.30 143 0.87 0.17 0.81 0.26 

Portunidae 1 1.00 0.00 1.00 0.00 

Paguridae 2 1.00 0.00 1.00 0.00 

Xanthi idae 135 0.92 0.22 0.84 0.30 139 0.93 0.21 0.90 0.24 

Pinnotheridae 163 0.95 0.11 0.76 0.30 233 0.86 0.15 0.80 0.19 

Grapsidae 19 1-00 0.00 1.00 0.00 18 0.97 0.04 0.97 0.04 

NEGALOPS 

Xanthiidae 3 1.00 0.00 1.00 0.00 4 0.88 0.18 0.88 0.18 

Grapsidae 60 1.00 0.00 0.97 0.06 27 1.00 0.00 0.99 0.02 

JUVENILES 

Lo7 1iguncula 

brevis 1 0.00 0.00 0.00 0.00 2 0.00 0.00 0.00 0.00 

-

-X = Mean survival (percent: multiply by 100).

S.D. = Standard deviation. 
-- -- -- -- -- 

Table A-40. L t t urvival of invertebrate larvae from Big Bend Screenwash 

Station for 24 and 48 hours, day and night sampling, July 1985. 

(1.00 = 100% survival). 

LATENT SURVIVAL 

DAY NIGHT 

No. , No. 

Organisms 24 hrs - 48 hrs Organisms 24 hrs - 48 hrs 

Taxa Tested W S.D. x S.D. Tested R S.D. x S,D. 

23 1.00 0.00 1.00 0.00 

Caridea 179 0.72 0.35 0.49 0.38 93 0.71 0.38 0.60 0.41 

1 1.00 0.00 1.00 0.00 

Paguridae 11 1.00 0.00 0.69 0.41 5 1.00 0.00 1.00 0.00 

Xanthiidae 70 0.94 0.20 0.81 0.33 66 0.89 0.26 0.82 0.31 

Pinnotheridae 366 0.88 0.15 0.68 0.26 516 0.85 0.13 0.77 0.18 

Grapsidae 10 0.91 0.15 0.70 0.40 25 0.91 0.19 0.91 0.19 

MEGALOPS 

Xanthiidae 2 1.00 0.00 1.00 0.00 4 1.00 0.00 1.00 0.00 

Grapsidae 10 -1.00 0.00 1.00 0.00 54 0.99 0.02 0.87 0.25 

JUVENILES 

Lo11 iguncula 

brevis 

-

-X = Mean survival (percent: multiply by 100).

S.D. = Standard deviation. 
Table A-41. Latent survival of invertebrate larvae from Big Bend Screenwash 

Station for 24 and 48 hours, day and night sampling, August 1985. 

(1.00 = 100% survival). 

LATENT SURVIVAL 

DAY . NIGHT 

No -- No. 

Organisms 24 hrs - 48 hrs Organisms 24 hrs - 48 hrs 

Taxa Tested Y S.D. x S.D. Tested 51 S.D. x S.D. 

ZOEA 

Penaeidae 1 1.00 0.00 1.00 0.00 12 0.92 0.14 0.92 0.14 

Caridea 202 0.84 0.18 0.54 0.33 176 0.84 0.18 0.75 0.22 

Portunidae 12 1.00 0.00 1.00 0.00 4 0.90 0.14 0.90 0.14 

Paguridae 5 0.38 0.48 0.38 0.48 3 1-00 0.00 1.00 0.00 

Xanthiidae 126 0.87 0.23 0.74 0.30 64 0.94 0.20 0.89 0.28 

Pinnotheridae 284 0.83 0.18 0.60 0.27 472 0.88 0.08 0.67 0.16 

1 Grapsidae 6 0.70 0.45 0.70 0.45 18 1-00 0.00 1.00 0.00 

I MEGALOPS 

Xanthiidae 3 1-00 0.00 1.00 0.00 7 1-00 0.00 1.00 0.00 

I Grapsidae 200 0.99 0.02 0.97 0.08 142 0.99 0.02 0.99 0.02 

E JUVENILES i Lo11 iguncula 

brevis 

i 

t ­

-X = Mean survival (percent: multiply by 100).

S.D. = Standard deviation. 1 

i 

f 
-- 

-- 

Table A-42. Latent survival of invertebrate larvae from Big Bend Screenwash 

Station for 24 and 48 hours, day and night sampling, September

1985. (1.00 = 100% survival). 

LATENT SURVIVAL 

Taxa 

ZOEA 

Penaeidae 

Caridea 

Portunidae 

Paguridae 

Xanthiidae 

Pi nnotheridae 

Grapsidae 

MEGALOPS 

Xanthiidae 

Grapsidae 

JUVENILES 

Lo1 1 i guncula 

brevis 

-

DAY 

No. 

Organisms 24 hrs 48 hrs 

Tested ST S.D. Z S.D. 

266 

6 

11 

123 

354 

10 

37 

194 

0.85 0.21 0.72 0.29 

1.00 0.00 1.00 0.00 

0.75 0.42 0.75 0.42 

0.92 0.18 0.85 0.29 

0.82 0.18 0.67 0.24 

0.80 0.45 0.80 0.45 

0.99 0.02 0.96 0.09 

0.96 0.05 0.96 0.05 

NIGHT 

No. 

Organisms 24 hrs 48 hrs - Tested K S.D. x S.G. 

16 0.79 0.37 0.79 0.37 

187 0.87 0.22 0.75 0.32 

5 1.00 0.00 1.00 O.QO 

4 0.83 0.24 0.83 0.24 

123 0.91 0.22 0.85 0.30 

644 0.86 0.09 0.76 0.13 

14 0.83 0.41 0.83 0.41 

36 0.98 0.06 0.92 0.18 

200 0.98 0.03 0.95 0.06 

-X = Mean survival (percent: multiply by 100).

S.D. = Standard deviation. 
APPENDIX B 

FMS SURVIVABILITY STUDIES DATA 

ORGANISM RETURN DISCHARGE STAT1ON 
-- -- -- 

-- -- -- 

-- -- -- 

-- -- -- 

Table 8-1. Initial survival and hatchability of fish eggs, Organism Return 

Discharge Station, Big Bend Power Plant, for March 1985, day and 

night sampling. (1.00 = 100% survival and hatchability). 

MARCH 

-

DAY

No. Initial 

Organisms - Survival 

S.D. 

Total -

Hatchability

Tested X No. X S.D. 

CLUPEIDAE 4 0.58 0.11 

ENGRAULIDAE 229 0.24 0.25 64 0.83 0.32 

SCIAENIDAE 367 0.36 0.35 128 0.75 0.31 

SOLEIDAE 1 0.00 0.00 

-

NIGHT

No. Initial 

Organi sms - SurviVal 

S.D. 

Total -

Hatchability

Tested X No. X S.D. 

CLUPEIDAE 5 0.40 0.00 

ENGRAULIDAE 160 0.13 0.13 58 .o .91 0 -35 

SCIAENIDAE 2079 0.16 0.15 123 0.63 0.23 

SOLEIDAE . 1 0.00 0.00 

-

-X = Mean survival (percent: multiply by 100). 

S.D. = Standard deviation. 
-- -- -- -- -- -- 

-- 

-- -- -- -- -- -- 

-- 

1 

Table B-2. Initial survival and hatchability of fish eggs, Organism Return 

t

I 

Discharge Station, Big Bend Power Plant, for April 1985, day and 

night sampling. (1.00 = 100% survival and hatchability). 

1 APRIL 

-

DAY

No. Initial 

Organi sms - SurviVal Total 

Tested X S.D. No. 

1 CLUPEIDAE 

I ENGRAULIDAE 1143 0.29 0.28 23 9 

SCIAENIDAE 1212 0.31 0.23 277 

fI SOLEI DAE 1 1.oo 0.00 55 

t 

b 

f 

NIGHT 

No. Initia1 

Organisms - Survivaf Total i2, Tested X S.D. No. 

1 CLUPEIDAE f 

-Hatchability 

X S.D. 

0.90 0.28 

0.85 0.21 

1.oo 

-Hatchability 

X S.D. -

ENGRAULIDAE 209 0.08 0.12 150 -0 -87 0.31

1 

t SCIAENIDAE 5126 0.48 0.31 206 0.65 0.14 

j SOLEIDAE. 3 0.83 0.29 42 1.00 

! 

I -

-X = Mean survival (percent: multiply by 100).

S.D. = Standard deviation. 
-- -- -- -- -- -- 

-- 

-- -- -- -- -- -- 

-- 

Table 8-3. Initial survival and hatchability of fish eggs, Organism Return 

Discharge Station, Big Bend Power Plant, for May 1985, day and night

sampling. (1.00 = 100% survival and hatchability). 

-

DAY

No. Initial 

Organi sms - SurviVal 

S.D. 

Total 

Tested X No. 

i CtUPEIDAE 

ENGRAULIDAE 418 0.57 0.34 194 

SCIAENIDAE 985 0.43 0.41 169 

SOLEIDAE 3 1.oo 0.00 110 

I 

i 

I NIGHT 

No. Initial 

Organisms -. SurviVal I Tested X S.D. i 

I

E CLUPEIDAE 

Hatchabi1 ity -

X S.D. 

0.97 0.39 

0.97 0.38 

0.99 

Hatchabi1 i ty -

X S.D. -

ENGRAULIDAE 44 0.18 0.40 5 - 1 ..oo. 

I SCIAENIDAE 2713 0.73 0.19 139 0.76 0.26 

1 

I -

X = Mean survival (percent: multiply by 100). -

S.D. = Standard deviation. 

1 

E 

c 

i 

t

!