ENTRAINMENT OF ZOOPLANKTON BY A ONCE—THROUGH
COOLING SYSTEM ON WESTERN LAKE ERIE, 197h-1975

By

Roger Joshua Jones, Jr.

A THESIS

Submitted to
Michigan State University
in partial fulfillment of the requirements
for the degree of

MASTER OF SCIENCE

Department of Fisheries and Wildlife

1978

ABSTRACT

ENTRAINMENT OF ZOOPLANKTON BY A ONCE—THROUGH
COOLING SYSTEM ON WESTERN LAKE ERIE, l97h-l975

By

Roger Joshua Jones

The once-through cooling system used by the Monroe Power Plant
entrains large quantities of zooplankton through screens, pumps, and
condensers. In addition to these mechanical stresses, organisms also
were subjected to rapid temperature elevations and chlorination.

Since zooplankton represent the trophic link between algae and fish,
the impact of once-through cooling may be important.

In 197%, the mean annual densities of rotifers, copepods and
cladocerans decreased from one-third to two-thirds in passage from
the intake to the upper discharge canal. Biomass, and in most instances
size, also varied in this manner. These results were not as evident in
1975-

Mortality studies at the site indicated that in the summer of 1975,
lethal temperatures for many of the copepods and cladocerans were
reached. At 38°C in the upper discharge canal, mortalities averaged
76% among three replicate samples. In 1976, observations were restricted
to the largest zooplankter found during the study: Leptodbra kindtii.
The results showed an average of 60% of these organisms killed by

passage through the plant.

ACKNOWLEDGMENTS

I would like to thank Dr. Richard Cole for his advice and especially
for giving me the opportunity to become a member of the Lake Erie Project.
Thanks also go to Donna Gates for assisting with the microscope work and
to Drs. Niles Kevern and Richard Merritt for their manuscript reviews.

To my mother and father I am greatly indebted for wanting me to have
something better than they had. Without their initial financial and moral
support, a college career would not have been likely. Finally, I wish to
express my deepest appreciation to my wife Teresa, and daughter Jessica,
for their concern, good humor and love.

This study was funded by the U.S. Environmental Protection Agency.

ii

TABLE OF CONTENTS

LIST OF TAB’ES .
LIST OF FIGURES
INTRODUCTION .
MATERIALS AND METHODS
The Study Area
Mass Transport Studies
Hydrology .
Zooplankton Sampling

Mortality Studies . . . . . . . .

Laboratory and Statistical Analysis .

RESULTS . . . . . . . . . . . . . . .
Density and Species Composition .
Day vs. Night Comparisons .
Effects of Chlorine .
Statistical Comparisons . . . . .
Mortality . . . . . . . . . . . .
Diversity . . . . . . . . . . . .
DISCUSSION . . . . . . . . . . . . .
Impact of Cooling System Passage
Mortality . . . . . . . . . . . .
LITERATURE CITED . . . . . . . . . . .
APPENDIX A . . . . . . . . . . . . . .

APPENDIX B . . . . . . . . . . . . . .

iv

vi

10
10
13
13
15
15
15
30
3h
38
1:6
1&9
’49
53
56
58
83

LIST OF TABLES

Table

1. Amounts of river and lake water used to determine the
concentrations of zooplankton at station 18 in the
intake canal, velocities in the upper discharge, num-
ber of pumps in operation, water passage time through
the canal, total chlorine, discharge temperature and
temperature range (AT) . . . . . . . . . . . . . .

2. The distribution of mean total chloride (mg/liter)
and mean temperature (CO) at all stations, June 11
through October 21, 197k . . . . . . . . . .

3. The distribution of mean total chloride (mg/liter)
and mean temperature ( 0C) at all stations, May 16
through September 16,1975 . . . . . . . . . .

h. Percent composition of the taxa encountered in 197h
and 1975 O I O O O O O O O O O l O O O O O O O O O O

5. Mean density (numbers/liter) for the major taxa at each
station and time period for 197A and 1975. . . . . . . .

6. Mean biomass (pg/liter) for the major taxa at each
station and time period for 197k and 1975. . . . . . . .

7. Mean biomass (pg/liter) and size/individual for the
major taxa (combining stations) at the two daily
time periods in 197A and 1975. . . . . . . . . .

8. Mean annual density of zooplankton at all stations

9. Mean annual biomass of zooplankton at all stations
(pg/liter) in 197A and 1975. . . . . . . . . . . . . . .
10. Mean annual size/individual (pg) in 197A and 1975. . .
11. Results of a three day mortality study involving
copepods and cladocerans . . . . . . . . . . . . . . .
12.

(numbers/liter) in l97h and 1975 .

Results of a three day mortality study of Leptodbra

kindtii in 1976.

iv

. 35

. 36

. 37

. A3

. A?

Table

13.

A2.

A3.

B1.

B2.

B3.

Bh.

Diversity index values for zooplankton taxa captured
in the cooling system. . . . . . . . . . . . . .

Zooplanktonic distribution (number/liter) in the cooling
system (mean of five replicates) . . . . . . . . . . . .

Tukey's post-hoc comparison for mean zooplankton density
in 197A and 1975 . . . . . . . . . . . . . .

Tukey's post-hoe comparison for mean zooplankton biomass
in 19714 and 1975 o o o o o o o o o o o o o o o 0

Mean annual size/individual (pg) from November 1972 to
September 1973 (From Simons, 1977) . . . . . .

Mean annual biomass of zooplankton at all stations
(pg/liter) from November 1972 to September 1973
(From Simons, 1977).. . . . . . . . . . . . .

Mean annual density of zooplankton at all stations (in
numbers/liter) from November 1972 to September 1973
(From Simons, 1977). . . . . . . . . . . . . . . .

Mean density (numbers/liter) for the major taxa at each
station and time period from November 1972 to September
1973 (From Simons, 1977) . . . . . . . . . . . . . .

. 58

. 70

. 75

. 83

. 8h

. 85

. 86

LIST OF FIGURES

Figure

1.

lo.

ll.

12.

13.

1h.

Map of the study area in the vicinity of the Monroe
Power Plant . . . . . . . . . . . . . . . . . .

A generalized view of the steam—driven electrical power
generating system . . . . . . . . . . . . . . . . . .

The plant cooling system, stations, and station depths
in meters . . . . . . . . . . . . . . . . . .

The density of rotifers at each station and time period
dwing 19724 O O O O O O O O O O O O O O O I O O O O O O

The density of rotifers at each station and time period
during 1975 O O O O O I O O O O O O O O O O O O O O O O

The density of cladocerans at each station and time
periOd dllring 1971‘. o o o o o o o o o o o o o o o

The density of cladocerans at each station and time
period during 1975. . . . . . . . . . . . . . . . .

The density of Bosmina sp. at each station and time
period during 197A. . . . . . . . . . . . . . . . . .

The density of Bosmina sp. at each station and time
period during 1975. . . . . . . . . . . . . . . . . . .

The density of Daphnia retrocurva at each station and
time period during 197h . . . . . . . . . . . . . .

The density of Daphnia retrocurva at each station and
time period during 1975 . . . . . . . . . . . . . . . .

The density of copepods at each station and time period
duing l97h O O O O l O O O O O O O O O O O O O O O O O

The density of copepods at each station and time period
during 1975 O O O O O O O I O O O O O O O O O O O O O O

The density of Cyclops vernaZis at each station and
time period during 197A . . . . . . . . . . . . . .

vi

Page

l6

17

18

. l9

. 2O

21

. 22

. 23

, 2h

25

26

Figure

15.

16.

17.

l8.

19.

Al.

The density of Cyclops vernaZis at each station and
time period during 1975 . . . . . . . . . . . . . .

Mean densities (no./1iter) of copepods (A = afternoon;

I] = evening) and cladocerans (A = afternoon; I = evening)
at all depths and regression values based on the density
of each group at a particular depth in June 197A.

Mean densities (no./1iter) of c0pepods (A = afternoon;
D= evening) and cladocerans (A = afternoon; .= evening)
at all depths and regression values based on the density
of each group at a particular depth in August 197A.

Mean densities (no./liter) of copepods (A = afternoon;
D= evening) and cladocerans (A = afternoon; I = evening)
at all depths and.regression values based on the density
of each group at a particular depth in July 1975.

Mean densities (no./liter) of copepods (A = afternoon;
D = evening) and cladocerans (A = afternoon; I = evening)
at all depths and regression values based on the density
of each group at a particular depth in September 1975

The majority of zooplanktonic types captured in the

vicinity of the Monroe Power Plant during the 1973-75
studies . . . . . . . . . . . . . . . . . . . . . . .

vii

39

. ho

.h1

82

INTRODUCTION

In densely populated areas, like that around the western end
of Lake Erie, the demand for electric power plant cooling water has
been doubling every ten years. This has led to the development of
large fossil-fueled generating plants which produce h to 5 times more
electricity than those built 20 years ago (Cairns, 1971). The once-
through cooling systems utilized by such plants transport large quan-
tities of zooplankton through screens, pumps, and condensers. The
impact of once—through cooling is important since zooplankton serve
as a trophic link between algae and the fishery resource. The purpose
of this research was to quantify the passage of zooplankton through
the cooling system of a steampelectric station on western Lake Erie
and evaluate resulting impacts.

Plankton populations that are drawn through condenser systems
experience various and nearly simultaneous stresses (Davies and Jensen
197A). The magnitude of these stress factors is determined by (1)
ambient intake temperatures; (2) the rise in temperature (AT) during
and after condenser passage; (3) the exposure time to these elevated
temperatures; (A) physical damage resulting from turbulence and pres-
sure changes within the system and (5) exposure of the organisms at
certain times to chlorination used to prevent fouling of the condensers

(by bacteria, algae, etc.).

2

The impact of once-through cooling upon zooplankton at the Monroe
Power Plant was examined by collecting organisms from the plant intake
and outfall areas and by measuring (1) numbers and biomass of the im-
portant taxa; (2) their size distribution; (3) their capacity to orient
to normal vertical distributions and (h) their species diversity and

(5) mortality resulting from plant passage.

MATERIALS AND METHODS

Study Area

 

The Monroe Power Plant occupies a h85-ha site adjacent to the City
of Monroe, Michigan, where the Raisin River joins Lake Erie (Figure 1).
It is owned and operated by the Detroit Edison Company. The plant began
operating in May 1971, when the first of four 800-megawatt units started.
With the remaining units completed in spring 197A, the plant can gen-
erate up to 3,150 megawatts. It is the largest coal-powered generating
plant in the world and accounts for approximately one-third of Detroit
Edison's electrical output. During capacity output, cooling water is
required at a rate of 85 m3/sec (Figure 2) and, depending on power
generation and pumping rates, intake water is warmed up to 17°C (Table 1).

The cooling water is drawn from the Raisin River and Lake Erie
through an intake located about 1 km upstream from the mouth of the
river (Figure 3). Almost all of the river water is drawn before any
substantial makeup is drawn from the lake. The discharge of river water
may be as high as 120 m3/sec in the spring and as low as 3 m3/sec in the
late summer (Table 1). These fluctuations substantially influence the
proportions of cooling water used from both sources. Since there are
significant biological differences between the river and the lake,
seasonal variations will also determine the amount of biological ma-
terial contributed to the cooling system by each source.

After entering the intake, the water passes in sequence through a

traveling screen with l-cm diagonal openings, the condenser, a concrete

3

 

 

 

 

 

 

Monroe
1:
Q?
Plum [8
l» \MOH’OG
Discharge : {7 P777 L a/re
Canal F’ P an ‘
E r10
0,
”iii;
"an
Rois! n
Fflver
Brest
Bay
N
__. 1
I km. oak.
Maumu E"
[\_§_°J/"

 

 

Figure 1.

Map of the study area in the vicinity of the Monroe

Power Plant.

x2e. .825

053.350.
.cmzm 530%...

.m. 50 050cm
2.255 m . o

\

.Empmam wcwpwhmcmw
meson Hwofinpcoao ao>HnUIEwopm on» mo 30w> wouwadhmcow < .N ouswfim

.900
60...... Em:

we... £02m

.m 8520.
m. 38: .

 

 

0.0 0.mH mm. 0.0 w m.m wm w.wm m.~H Apmwv m>\mm\d
0.0H m.ma :0. m.m s m.: m: o.mm m.»a Aw>mv ms\:m\a
o.HH o.am 0m. 0.0 m m.m 0m w.am 0.; Apaav :P\Hm\oa
o.m m.am :0. m.m s m.: a: :.:: m.: Am>mv :>\ma\oa
o.w 0.4m ms. O.» OH :.0 o» m.:m H.m Asmav :s\ma\m
m.m m.mm as. m.0 Ha a.» as 0.0» 0.0 Am>mv :>\:H\w
o.» m.mm as. m.m HA a.» as m.Hm «.ma Apmwv zs\ma\0
0.0 0.0m H2. m.m HH a.» PP w.om 0.0H Am>ov :>\Ha\w
o.m o.sa ms. ;.HH 0 m.m m: o s.:m Apmwv zs\w\:
o.m 0.0H ms. :.HH 0 m.m m: o 0.0m Am>mv :~\s\:
0.w 0.:H ms. :.HH 0 0.m N: 0 m.m0H Apmwv :N\H\m
0.0 0.HH m». :.HH 0 m.m m: 0 m.mmH Am>mv :P\HM\H
m.MH 0.NH mm.H :.HH 0 m.m m: :.mm w.mH Apmmv m>\ma\ma
0.~H 0.0a mm.H :.HH 0 m.m N: 0.0m N.NH Am>mv m»\ma\ma
m.w 0.~m mm.H :.HH 0 m.m m: 0.Nm 0.m Apmwv m>\mm\m
0.> 0.0m mm.H :.HH 0 0.m m: m.mm p.m Am>ov m~\wm\m
0.: 0.0m mm.H :.HH 0 m.m m: m.Hm m.0H Apmwv m~\m\w
0.0 0.Hm mm.H :.HH 0 m.m m: 0.Hm 0.HH Am>mv mp\w\m
0.0 0.0m m. m.> 0 w.m m0 0.m: 0.0m Apmwv m>\ma\m
o.m o.sm m. m.s m w.m m0 o.H: o.mm Am>mv m>\aa\0
0.0 0.NH mm. m.> m w.m mm 0.0m 0.m: Apmwv mw\m\:
m.0 0.0a mm. m.» m w.m m0 0 o.mm Am>mv m>\om\m
m.m 0.~ mm. m.» m w.m mm w.0m m.m: Apmwv m~\:m\a
m 0.:H mm. m.» m m.m mm w.m: :.~H Am>ov m>\wa\a
0 o.mH m0.H :.HH 0 m.m m: o o.mm Apaav ms\oa\m
0H 0.0a mw.H :.HH 0 m.m m: 0 :.Nm Am>mv m>\m\m
B< on popHH\mE mhdom Gprwnmmo owpwsomfla .D Aoom\msv Aoom\mav Aomm\mav ovum
mndpmhmmEoB sawhoazo mafia :H mmsdm Aomm\Eov wwthQmwm nmpwz hopwz
mwgwnomwm owmmmwm mo honesz hpwooao> Hmpoa oqu um>wm

 

.AB<V owcmco mndpmnomaop 0cm ohdpwpomEop mmgwnomwc .ocflnoamo Hdep .szdo msp nwfiOAQp mawp owwm
imam pops: .cofipwhwmo ca mQESQ mo gonad: .mwuwSUmflc nomad map cw mowpfiooao> .Hmcmo mxwpcfi map aw
ma cofipmpm pm GOpxcmHmooN mo muoflpmhpcmocoo map mawfihmpoc op 00m: nova: oxwa 0am hm>wn mo qudoa< .H manna

 

 

m.m 0.0m mm. ~.m NH w.» :w 0.Nb m.mH Apmwv m>\ma\m
:.0H :.mm mm. >.m NH w.» :w m.m> N.mH Am>o vmb\ma\m
Tm 06m 0m. 12m m: 0;. :0 ads 0.: 3.23 3&me
9w m.mm mm. lam ma 0.» :w 52. 0.: A880 math:
m.HH 0.0m mm.H 0.:H m m.m mm w.>H >.ma Apmwv m>\>H\m
0.mH 0.wm mm.H 0.:H m m.m mm m.>H m.>H Am>mv mw\ma\m
0.:H m.mH 0m. 0.0 w m.m mm m.0m w.mm Apmmv m~\ma\m
0.mH 0.0m m». :.HH 0 m.m m: m.mH 0.0m Am>mv m~\ma\m
BQ on hmpfla\w8 mpsom coflpmammo mwhmnomflm .D Aomm\mav Aomm\mav Aomm\mav mpwm
mhdpmhomsme maflnoano mafle :H mmasm Aomm\aov omhdnomwm hopes Hopw3
mmpmnomfim mwwmmmm mo honesz hpfiooam> Hmpoe mxdq pm>wm

 

A.0.vnoov H mHQwB

.mampme :fi
mzpmmw Qprmpm cad .mcoHPwpm .Empmam wcfidooo pawam one .m mhdwwm

 

 

 

 

 

 

 

 

 

 

aim
.83 q
ul|\\\\\\\
a o
a
e Emfixbcfim
23 @
mmwguwfil . «math ESQ.
neoo
003.6% g
1 /\.
0030 g 50>O
O 30;
fl Q .980
o m. ._. 1m,
o n © o t SE 3:339:qu ewe @ as Q Swank
N v . m& \ \ \ Q . . b 7 N . . .

 

9

conduit, and the discharge canal. The condenser consists of 18,15h
tubes each with a length of 17.6 m and a 2.5h-cm outside diameter.
Velocities during full operation within the condenser tubes are over
2 m/sec and decrease to about 1 m/sec in the 350 m long concrete conduit.
The discharge canal averages 175 m wide, 7 m deep in the upper end, 3 m
deep in the lower end and is 2000 m long. Velocities in the upper dis-
charge canal approach 1 m/sec but are not uniform as a result of high
velocity conduit water entering the west side of the discharge canal.
This forms an eddy of slower water on the east side and adds to the
variability in the residence time for the entrained organisms. During
maximum output, water passage through the cooling system back to Lake
Erie averages about h.5 hours. Passage time through the individual
parts of the cooling system are seven seconds through the condenser, 20
minutes through the concrete conduit, and four hours through the dis-

charge canal.

Mass Transport Studies

 

In order to assess the impact of once-through cooling upon zoo-
plankton, five stations were chosen for sampling in the vicinity of the
plant (Figure 3). The intake was represented by a station upriver (9)
from the plant, at the mouth of the river (17), and by an "artificial"
station (18) calculated from the river and the lake contributions.
Stations 17 and 9 were chosen from the intake region because the water
at these points could be representatively sampled with relatively few
samples. Since the water in the short intake canal was an incomplete
mixture of river and lake water, theoretical concentrations at station
18 were calculated from data obtained at stations 17 and 9 in order to

compare water at station 12 to the mixture from the two sources. This

10

was done by proportioning plant cooling water demands from stations 17
and 9 using USGS measures of river discharges and records of Detroit
Edison's pumping rates (Table 1). The outfall area consisted of a
station immediately downstream from where the effluent enters the dis-
charge canal (12) and a station about 1000 m downstream from this (8).
Station 8 was sampled to evaluate the effects of prolonged exposures of

organisms to the heated waters of the discharge canal.

Hydrology

Water samples collected in the intake and outfall areas were
analyzed at the Michigan State University Lab to determine the concen—
trations of chloride and various forms of nitrogen. For the purposes
of this study, chloride was measured in order to confirm mixing ratios
in the intake (Table 2, 3). Chloride analyses were accomplished
through the mercuric nitrate titration of a 25-milliliter sample to
the diphenylcarbazone-mercury complex endpoint. These values then were
indicative of the respective amounts of river and lake water used in the

cooling process.

Zooplankton Sampling

 

Sampling began in November 1972, and continued until September
1975. The purpose of my study was to analyze data collected from
December 1973 to September 1975, when the plant was operating with all
four units. The findings, as well as having their own interpretation,
could then be compared to the results of a 1972-73 study (Simons, 1977)
when the plant had only two or three units functioning sporadically.
Zooplankton samples were collected during the afternoon and evening

over a two-day period every two months. The afternoon sampling began

ll

.0Q00c500 0003 :o0xcwamoou 00:: 00800 00 0003 0H000 00:0 :0 200030000 000 00000H00 00000

.0000800 m mo name 030 00 05H0> £00m

N

H

 

 

 

0.00 0.00 0.00 0.00 0.00 000: ceano
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 A0000 :0\H0\00
0.00 0.00 :.00 :.00 0.00 0.00 0.00 0.00 0.00 0.00 Am>0v :0\0H\00
0.00 0.00 0.:m 0.00 0.00 0.00 0.00 0.0: 0.00 0.00 A0000 :0\00\0
0.00 :.00 0.00 0.00 0.00 0.00 0.00 0.0: 0.00 0.00 A0>0v :0\:H\0
0.00 0.00 :.00 0.00 0.00 0.00 0.:0 0.00 0.00 0.00 A0000 :0\00\0
0.00 0.00 0.00 0.00 :.00 0.:0 0.00 :.0m 0.00 00.00 Am>0v :0\00\0
000 00 000 00 009 00 0oa 00 000 00 0000

0000000

 

H.:~0H .HN 0000000 0050000 Ha 0q30
.05000000 000 00 Aoov 00500000800 2008 0:0 A0000H\msv 00000000 H0000 :008 no 000030000000 009 .N manwe

12

.00H0800 m 00 8008 0:0 00 08H0> 000m

 

 

 

N
.08008800 0003 800080Hmoou 8003 00800 00 0003 0H000 0000 80 80008Ho80 000 00000H00 00000H
0.HN m.0N o.HN m.om m.wH 8002 08000
0.:N N.NN 0.mN 0.NN 0.0H m.HN m.>H 0.0N 0.0H 0.0N A0M0v m0\wH\m
m.mN 0.MN m.wN :.NN m.mH m.NN n.0H o.mN m.mH N.HN A0>0v m0\mH\m
2.:m 0.0H o.mm N.0H 0.0N m.mH 0.0N ®.mm 0.0N :.mH prdv m>\®N\N
m.mm m.mH m.mm :.mH 0.:N m.mH m.MN N.Om 0.:N 0.:H Ambmv m0\NN\N
0.0N w.mN H.®N 0.:N 2.0H m.mN N.®H 0.0m m.mH :.HN Apmdv mb\NH\m
0.00 0.00 0.00 0.00 In- 0.:0 uu- 0.00 0.00 00.00 00>0v 00\00\0
009 HO DOB Ho DOB Ho DOB Ho DOB H0 0009

NH wH 0 NH

0000000

 

0.0000 .00 000000800 0000000 00 002
.08000000 HH0 00 Aoov 00800000800 8008 080 A0000H\m8v 00000H£o H0000 8008 mo 800080000000 009 .m 0H00B

13
at midday, while the evening samples were gathered promptly after sunset.
During the evening period in the summer months was also when the plant
cooling system was chlorinated. Sampling consisted of five replicates
taken from randomly located depths at four stations (Figure 3). By
using this sampling scheme any diurnal variability in the entrainment of
organisms could be observed. Sampling at two-month intervals included
the varying contributions of river and lake water to the cooling system

and also changes in the dominant organisms.

Mortality Studies

 

The mortality of zooplankton in the cooling system was estimated
by Simons in June 197h, and by myself in August 1975 and July 1976.
Samples were collected from the intake and upper outfall areas usually
at the same random depths used in the mass transport studies. The times
of day chosen to sample represented extreme conditions for temperature

change, chlorination and mechanical stress.

Laboratory and Statistical Analysis

During the long-term entrainment studies zooplankton were obtained
using an 8.1-liter VanDorn water sampler. Once collected, each repli-
cate was concentrated using a #25 Wisconsin plankton bucket and pre-
served in 5% formalin. The samples were then diluted to a known con-
centration (lO-hO ml) and a l-ml aliquot was extracted and placed in
a Sedgewick-Rafter counting cell. The organisms were then counted,
measured (using a Whipple micrometer), and identified to species when
possible. From this information population densities, biomass, and

species diversity indices were calculated.

1h

Zooplankton volumes were estimated by using linear measurements of
length and width to calculate the volume of a common geometric figure
(Weast, 1968) that was similar to the shape of the organism. Dry
weights were then estimated from the volumes by assuming that this meas-
urement was 10% of the plankton wet weight (Cummins and Wuycheck, 1971).

Analysis of variance was conducted among stations (combining depth)
on the density and biomass of the following taxa: Rotifera, Cladocera
and Copepoda. To meet the conditions required for analysis of variance,
the log (x + l) transformation was employed. This was then followed by
Tukey's test of paired comparisons if significant (a = 0.05) differences
existed (Sokal and Rohlf, 1969). Coefficients of linear regression were
calculated to estimate the relationship of organisms to depth after they
were subjected to the stresses of cooling system passage. The diversity
of 200plankton at each station was determined by using the species di-

3
versity index H = —Z(NJ/N)loglO(NJ/N) where N3 = the abundance

J = l
of the jth species, N = the total abundance of all species and s =
species (Pielou, 1969).

During the mortality studies of l97h and 1975, zooplankton were
collected with a h-liter VanDorn water sampler at five random depths
from the intake and discharge areas. The samples were pooled and con-
centrated to a l—liter subsample, filtered, and placed on a separation
dish. The organisms were examined under a dissecting microscope with
numbers of dead and alive organisms being recorded. Death was sig-
nified by a lack of movement. The 1976 mortality study involved only
the large cladoceran, Leptodbra kindtii, which was collected from the

intake and upper discharge with a 1-m (560u-mesh) tow net.

RESULTS

Density and Species Composition

 

Twenty-nine taxa of Rotifera, nine taxa of Cladocera and seven taxa
of Copepoda were identified from the samples collected in the plant's
discharge and intake systems from December 1973 to September 1975 (Table
b). Although rotifers appeared on all of the sampling dates, they were
most abundant from May through October (Figures h, 5), with synchaeta,
KerateZZa and Brachionus represented by the greatest numbers (Table A1).
Bosmina sp. and Daphnia retrocurva were the most common cladocerans from
June through October, but were absent in January, March and April
(Figures 6-11). Copepods were present in all months except January and
were most common from May through October. Immature copepods (nauplii
and calanoid and cyclopoid copepodites) were more common than adult
copepods which were dominated by Cyclops vernalis (Figures 12-15).

These results indicate that although zooplankton are drawn through the
plant's cooling system throughout the year, the majority of them ex-

perience plant passage between May and October.

Day vs. Night Comparisons

 

Comparisons between afternoon and evening abundances showed that
there was less variation over the short-term periods and no distinct
relationship between abundance and time of the day sampled (Figures 6-
15). There were occasions when densities found at different times of

the day at each station varied up to 100% or more of each other, but

15

16

300 I Evening

 

 

 

N)
f UAfternoon
8 ISO
CD
q- 300‘
1*
c ISO”
0
.3 _
PI 300'
a; ‘3 ISO"
3: o.
.J < _ —
\
‘—
é E 300'
:3 g I50-
5

 

Aug'74

 

 

 

 

   

 

: N

- q. .9 ii

8 I50 I: ID
I? 9 I8 '2 8

Figure h. The density of rotifers at each stati

on and time period
during 197h.

ID
1‘
c:
C!
‘3
ID
[s
A:
0
8-
C3
52
:2:
.J
\IO
h."
g >.
5%
:3
2
Figure 5.

17

300- . Evening
[:1 Afternoon

W

6':
o

 

— on
on o
o o

I

 

    

 

 

I?

The density of rotifers at each station and time period
during 1975.

18

. I Evening
[3 Afternoon

(N
O
O

Dec'73
E;
C)

H

 

L”
O
O

r

Jon'74
23
O

 

 

 

 

 

I J.. LII 1 J-__l
w
y—SOO'
L. —
:g 'E'HSO'
—’ 4 19
\ I ll 1 ll 1 L4 1 ll
3
.0 v300'
E 3»
:3
2 2:50-
= I
'3

300 t

Aug'74
5;
O

 

CH
O
O

Oct'74
E3
(3

 

 

l7 9 I8 l2 8

Figure 6. The density of cladocerans at each station and time
period during l97h.

l9

 

 

 

 

 

 

_-Evening
3 300 DAfternoon
5 ISO“
.3 1 ,L 1 1 1 1 1 1 1 l L
B 300-
-;:
2 I50'
0
2 1 11 1 1 1 1 1 l l l l
52
:1 ID 300’
\ 1‘
a3 3 ISO"
‘3 2
g h— 11 1 1_—_._I..—n—__l ‘
Z
in 300'
I"
.3150-
.7

 

0‘

O

O
1

 

Sept '75
a:
0

I7 9 I8 I2

Figure 7. The density of cladocerans at each station and time
period during 1975.

Number/ Liter

June '74

Dec'73

Jan'74

Aer'74

Aug'74

Oct '74

2O

 

 

 

   

 

 

 

 

 

 

_ .Evening
60 CIAfternoon
30'
-=_—_1_-=_1_1_.1_—::1
60‘
30'
1 1 -—- —=_1_=_—_.|
60*
30'
60
,-_l Jjfl
60
3O
1 - 4L-__
60
3O 1 ._l n E
I? 9 l8 ' I2 8
8. The density of BOSMina sp. at each station and time

period during 19TH.

21

 

 

 

 

 

 

 

 

 

IEvening
10 60'- [:IAfiernoon
1‘
g 30"
.3 l l l l l l
p 60'
f: 30~
o
2 l l l l l l l l L l l L l
E:
:1 no 50"
\ 1‘ 30
L- )5 "
0 O
.o
E 2 l l l l j l l 1 l F—q I l
:i
Z
in 60'
J?-
3.1 b
3 3O
-) IIII III. 'III
1.0 60"
1‘
E‘ 30 '-
(D - _ — —
l7 9 I8 I2 8

Figure 9. The density of Bosmina sp. at each station and time
period during 1975.

03
O

Dec'73
o:
0

Jan '74
(N m u c»
O O 0

April '74
O

Number/Liter
on m
o 0

June '74

O

Aug'74
on m
C

0403
O

Oct '74
0

Figure 10.

 

22

 

 

 

.. .Evening
DAfternoon
P
1 1 1 1 1 1 1 1 1 1 1 I l -#J
r--11 1 1 1, 1 1 1 1 1 1 1 1 __J
1 1 1 1 1 1 1 1 1 1 1 1 1 __j

 

 

 

 

 

 

 

 

 

 

.
r--1 1. 1 1 1 r-1 1 .1 I I I —J
.
P
1 1 1 I I I. I ‘ l ‘ ‘ ‘ ' *‘J
l7 9 I8 l2 8

The density of Daphnia retrocurva at each station
and time period during l97h.

23

 

 

 

 

 

 

 

 

 

60..Evening
:2 DAfternoon
g 30-
'1
:2 so-
1:
:3 30'
o
z 1 l l l 44 1 l l 1 1 l 1 J
L.
a)
«.—
-_-_-. «'3 so-
\ 1-
a; 5‘ 30-
.1: 2
E5 1 1 1 1 1 1 1 1 1 1 1 1 1 1
a
Z
in 60'
1‘
2‘ 30
:3
j — —
[D 1-
1‘ 60
3 3O
00

 

i—l. .. f.r—1-'___|
l7 9 l8 I2 8

Figure ll. The density of Daphnia retrocurva at each station and
time period during 1975.

2h

 

 

 

 

 

 

 

 

 

_.Evening
"'3 300 [:lAfternoon
’0 I50"
a:
D W
q 300’
1‘
c: |55()"
o
.3 I I I I I 1 l 1“
<r 300*
1. 1‘
.93 .1: I50“
:1 a
\ <1
2‘3
-_-, -
Z 2 I50
:1
.3
1 300
'r~
<I
<r ESCDCD .
1‘
~ I50"
0
O — — — — —
I7 9 l8 I2 8

Figure 12. The density of copepods at each station and time period
during l97h.

25

_ . Evening
300 D Afternoon

 

 

 

 

 

 

Number/ Liter

 

 

Sept '75
5'1
0

- — - - —
I7 9 I8 I2 8

Figure 13. The density of copepods at each station and time period
during 1975.

26

_ . Evening
CI Afternoon

03
0

086.73
C”
O

 

 

0403
O
f

Jon'74
C)

 

0403
O
r

Apfll'74
O

 

Number / Liter
on o:
C) (3

June ' 74

 

 

 

 

0105
CO

 

Aug'74

 

CH I03
0
l

Oct'74
C)

 

r—fl1ll1r1-_1_=

I7 9 I8 I2 8

Figure 1h. The density of Cyclops vernalis at each station and
time period during l97h.

27

 

 

 

 

 

 

 

 

m 601-. Evening
_l\ DAfternoon
5 3o-
_,
“,3 soL
J:
g 30"
o
z 1 L l 1 l l 1 l l l 1 1 J
L
.23
" ID
(I 1‘ 601'
L— >~1 I-
8 g 30
g 1 1 1 1 1 1 1 1 1 1 J_-_,|
Z
to I-
} 60
3‘ .
3 30
.3
in 60'
[x
E. 30'
a:
‘0 ‘ 1 - 1 1 __1_-__1_-_.1

 

 

I7 9 I8 I2 8

Figure 15. The density of cyclops vernaZis at each station and
time period during 1975.

28

Table A. Percent composition of the taxa encountered in l97h and 1975.

 

Percent

Taxa 1974 1975

 

ROTIFERA

synchaeta sp. 3 .
Karatella cochlearis
Brachionus angularis
Karatella quadrata
Brachionus calyciflorus
Pblyarthra sp.

Asplanchna sp.

Brachionus havanaensis
Trichocerca sp.

Pbmpholyx sp.

Brachionus budnpestinensis
Chromogaster sp.
Brachionus caudatus
Kératella earlinae
Brachionus urceolares
Filinia longiseta
Brachionus quadridéntata
Notholca sp.

Kellicottia longispina
Cbnochilus unicornis
Keratella valga

Rbtaria neptunia

Euchlanis sp.

Gastropus sp.

Ploesoma sp.

Ascomorpha sp.

Kératella hiemalis

Lecane sp.

Cephalodélla sp. 0.005

U'IU‘II’DIDOOOEUTW-II‘U'IGDCN
ONIUU'IWNUJWIUU'IQCDO

Mali-4
\OCDO\

WU)
O\I—‘

CDCDCDFJRJF‘P’F’F‘
n>m>cro>oaoaoxm>0\
c>c>
RJU1

OOOOOOOOOOOOI—‘OI—‘OI-Jt-‘ww-t’I-‘ChL/Om
0
ID
0000
S'JT'OJI’

O
l\)

F4 F’H
C>C3C>C>C>C>C>C>C)C>C>C>C>C>FJFJF’RDFJKDFJv1u1C>~J2*O\

O

0

ID
'00.
I I 000
MID“)

CLADOCERA

Bosmina sp.

Chydbrus sphaericus
Daphnia retrocurva
Diaphanosoma sp.
Leptodbra kindtii
Daphnia galeata mendotae
Cériodbphnia sp.

Alana sp.

Mbcrothrix sp.

OOOOOTDI-‘Ch
OOOOI’DOQOD
[UNIV-VJ?

I

I
O
O
0
U1

Table A (cont'd.)

29

 

 

Percent
Taxa 1974 1975
COPEPODA

Nauplii 19.9 l3.h
Immature cyclopoids 2.8 2.2
Cyclops vernalis 1.9 1.3
Immature calanoids 0.22 0.76
cyclops bicuspidotus 0.33 0.22
Diaptomus ashlandi 0.17 0.13
Diaptomus siciloidés 0.22 0.18
Diaptomus sicilis 0.0h 0.12
Eurytremora affinis 0.11 0.01
Diaptomus minutus -— 0.07
Diaptomus sp. -- 0.005

 

30

these fluctuations were outweighed by the similarity in afternoon and
evening samples found at station 12. Because water at station 12 was
thoroughly mixed it should have provided the most representative samples
for detecting day and night numerical differences. Mean annual densi-
ties followed no consistent patterns related to time of day (Table 5).
Although there were more organisms captured during 197A, afternoon and
evening density differences for both years among major taxa and total
organisms were generally less than 50 and 11%, respectively. The total
ZOOplankton biomass also showed only minor, short—term temporal differ-
ences, but in this case, the evening samples in both years generally had
the highest biomass (Table 6). Six of the nine zooplankton categories
in 197A, and seven of nine in 1975, exhibited the greatest biomass in the
evening samples; consequently, the mean size of the organisms was great-

est at this time, especially in 197A (Table 7).

Effects of Chlorine

 

Analysis of short- and long-term densities revealed no apparent
effects from regular chlorine applications in the morning and evening
(Figures 6-15; Table 5). Had chlorine been important, a decline of
zooplankton abundances should have been observed at station 12 in the
evening, and particularly in the afternoon at station 8. High veloci-
ties and turbulence may have masked the influence of the chemical on
plankton concentrations at station 12, but its effects would have been
noticed downstream at station 8 several hours later. Mean numbers of
organisms found at the discharge stations in both years did not seem to

follow a pattern that was determined by biocide applications.

31

 

 

 

 

 

 

 

 

 

 

~.<HH o.o- N.no <.amH n.wo «.mmfi w.no m.m- w.en «.mma Hm.nm m.ac~ n.sn~ o.He~ m.<wu n.ccn munch
s.o~ c.1s n.A~ ~.nm o.mH o.os A.x_ s.Hs m.n~ o.oe ~.H~ m.- n.m~ n.s~ n.- o.wa acoaoaoo "cues
n.m~ n.on m.mH ~.wc e.cH o.nm ~.~H a.o< m.HH c.5n o.- ~.<N m.- c.0N m.ma w.n~ «uaasaz
q.n m.m ~.H «.8 N.n n.@ q. a. o.~ s.@ no. n.N c.~ N.n e. e.n mm~8§hma .0 ufiav<
5.8 m.m w.H o.“ ~.q m.¢ m.H m. o.~ n.m mu. ~.n o.n m.n o.~ N.e uvonuaou uH=v<
q.~ o.mH w. m.o m.~ o.m~ w.~ n.0H n.a o.MH an. o.m o.~ H.w ~.n n.HH .no urwsoom
m.n n.H o.~ o.n o.H o.~ N.H m.m o.n o.~ N.~ n. o.< c. o.w s.eu .mm uvrxmum
¢.HH n.¢~ N.¢H o.oH N.“ m.oN o.oH m.<H c.n m.oN ~.n n.HH c.~H n.NH o.NN o.on uuuuovnuu
«.mm H.~mH m.om ~.<m ~.~n N.wm H.ao ~.¢HH @.nn ~.wm c.wm n.HHH «.mea o.<o~ o.HcH o.AoH nouwuox
muaa «Baa maoa «nan mama chad mNoH «Boa msou «nofi mumfi whoa mnoa ohm“ nmaH enma mxmh
acwco>u coocuwuw< mafico>u coocuouu< wcfico>m coocuouu< magno>m coocuouu<
NH «H

 

.mnoa pcm «moa no“ vofipon mean was acuumum some um mxmu Acmme ago new Auou«~\muobsscv >uamcov Com: .m

«Anus

32

 

 

 

 

 

 

 

 

 

 

o.~o~ H.oo o.~q o.m~ o.c- N.mm m.qm n.m~ c.om n.¢o a.oo a.- n.oo H.N~H o.nnm ¢.HNH Hench

~.oH o.n~ n.n ~.mn o.mH q.on H.ma m.~ N.m w.ma a.N n.m n.5H n.m¢ n.~n o.¢H avoaonou douOH
~.N c.¢ n.n n.n H.c ~.m o.m o.n o.~ s.~ ~.N o.~ n.~ H.m ~.e N.h wudnsmz
n.H~ ~.a m.c a.m~ m.m ~.- m.H hm. c.o ~.HH He. m.m c.- w.nN oh. o.n mwNutha nuufiau<
o.hH «.mH o.e n.c~ o.HH m.cN ~.oH m.~ o.o H.mH ON. ~.m N.MH N.¢e. n.” o.m avoaoaoo uanv<
m.~ o.m n. m.o ¢.N H.c m.n N.c c.H c.n 5H. n.~ mm. n.¢H ¢.N o.oH .ao Uflwsfiom
o.mo m.m m.- m.o~ ~.n¢ N.Hm H.o o.e m.~N m.w N.NH o n.5N n.mm H.mn H.anH .au aflxxuga
«.59 o.cH «.mm n.m~ H.HoH m.om o.q~ m.NH m.- w.m~ H.oo H.¢ o.nn o.on o.noH o.¢nu uuuoovmmu
m.m~ m.o~ H.m «.ma w.m o.- m.o m.~ m.n n.0N a.m ~.NH N.a m.NH o.c~ m.nH uuuuauox
nmma chad mead c~¢~ mmoa «soa whoa «Rafi whoa «Noa whoa csaa muma «mam nnma chad oxah

mcuco>m coocuouu< wcucw>m coocuoua< wcwco>m coocuouu< madco>m coocuouu<

NH

 

.mmaa new cnafi AOH coHuoa

mewu can c0auwum :oao an oxen uofiws ecu ham Auou«~\mav homeown coo: .m

«Haas

33

Table 7. Mean biomass (pg/liter) and size/individual (pg) for the major
taxa (combining stations) at the two daily time periods in 197A

 

 

and 1975.
Afternoon Evening
Biomass Size Biomass Size

Taxa 197A 1975 197A 1975 1975 1975 1974 1975
Rotifera 53.8 36.1 .10 .12 65.0 h1.7 .1h .12
Cladocera 179.5 206.3 2.5 3.7 128.6 22h.h 1.51 5.8
Daphnia sp. 15h.5 99.3 7.2 7.6 81.2 210.7 10.1 15.5
Bosmina sp. 23.2 6.9 .6h .96 35.2 6.8 .58 .8h
Adult Copepoda 39.5 22.6 2.6 h.1 105.2 50.7 1.0 3.5
Adult 0. vernalis 25.1 7.h 2.1 3.6 66.1 ho.h 3.6 3.6
Nauplii 17.7 13.1 .09 .20 15.9 11.7 .12 .22
Total Copepoda 67.2 36.0 .33 .h9 121.1 61.h .77 .90

Total 300.5 278.h .33 .6h 314.7 327.5 .hh .70

 

3h

Statistical Comparisons

 

Although there were consistent trends in the comparisons of annual
mean densities (Table 5), significant (0 = 0.05) differences were not
common on the individual sampling dates (Table A2). On 11 of 36 occa-
sions in 197A, and 7 of 36 in 1975, the difference among station means
for the six zooplankton groups was significant. Concentrations of zoo-
plankton collected at station 17 during both years were always greater
than those found in the river at station 9, and on 12 of the 18 dates
in 197h-75 when zooplankton were common, these differences were signi-
ficant (a = 0.05) for most of the taxa. The biomass of organisms col-
lected at these stations varied similarly; biomass at station 17 was
greater than station 9 on 15 of 18 dates when zooplankton were common.
Again, on 12 of these 18 dates, the differences were real (0 = 0.05)
for most of the taxa.

Comparisons between the densities at the intake and discharge
stations revealed few statistical differences (a = 0.05). Consistent
depressions in abundances appeared as a result of cooling system passage
from station 18 to 12 (Table 8), but only on three dates were these losses
determined to be significant (Table A2). During both years stations 17,
18, 12 and 8 were not often different from each other while station 9
was usually much lower.

In l97h, the mean annual densities of all major zooplankton taxa
decreased from one-third to two-thirds in passage from the intake to the
upper discharge canal. Biomass, and in most instances size, also varied
in this manner (Tables 9, 10). Passage from station 12 to station 8
showed a slight increase in mean annual numbers for all taxa except

Cladocera and Daphnia sp. which decreased. Biomass fluctuated similarly

135

.nuoalac ouuuuao euconouaoxe

 

 

 

 

 

 

 

an.nava.mon Am.m~avo.mgfl 15.navn.xa 16.0618s.n6~ Aa.en~va.~ea Ao.nm~o~.~n~ Ao.oso~.mo An.aA~vn.ne~ An.n-8~.uo~ Ac.c-vo.en~ Annoy

A~.o~oo.o~ Ao.eq8n.ce Am.-co.an Ao._n.~.es AA.A~8~.6A Ae.~m86.nn an.~vo.~A A~.o~oo.n~ An.-oe.a~ .A.amvc.do aeoaoaoo Assoc

Ao.snvo.hd Am.onon.~m As.mvm.mn no.o~v~.an Am.o~o~.¢. A6.6qve.oe An.~8m.~A A~.o~vn.- Ae.agvo.n~ A~.onvo.qn «AAaaaz
Am.nvn.~ An.nom.n Ao.svm.1 Ao.mam.n Ac.~va. A6.m86.n A~.vo.~ Am.vu.~ Afi.HVn.H Am.nv~.s amNegau: .6 u~=v<
An.nvn.n Ao.nv~.o A_.svm.~ Ao.mvo.s Aq.non.~ Aw.mv~.n a~.vfi.~ Am.vc.n Aa.Ava.~ An.mv~.e aeoaoaoo unav<
Ao.~vo.~ A~.~vo.- A-.Vx.~ Aq.oc~.~n Aa.m86.~ 15.118~.6H Ac.~8mm. Am.mve.h Ac.ov¢.~ ah.-85.o~ .au newsman
Ao.~8a.~ Ah.~vm.a Ao.nvs.~ hovo.m Aa.nvn.o Ah.ov~.~ Ao8¢.~ onn. Ao.~vo.o Ao.nfivo.a .au engeanq
Ao.~vn.mH Ao.n8~.an A1.sao.m Ao.Hnoe.a~ Ao.o~om.6H An.-os.m~ Ao.~vn.n Anfinfivm.gfl .o.HHvo.AA Aw.onvh.dn «nouondou

A~.-Vo.oo A~.m~on.nfid An.AAVo.oA Ao.so~vg.no~ Am.a-vo.oo~ An.nA~oH.nm~ An.nnvn.he Ao.nmvn.aofi Ac.nofiv~.nqu «a~.~oAVH.~oH assuage“

«son caafi «sol egoA was“ «Nan when «Asa who“ «had axes

NH

mm

a

 

.msoa van chm" cu Auouw~\auona:cv ecouuouo ago an acuxceunooa no uuumcov fiancee coo: .m

 

«Anne

36

. OHMfiBS—u Ouwuhflm QUBUMOHQUK¥

 

 

 

 

 

 

 

AH.~mVo.mn an.~cvo.~o As.cmvc.mm Ao.an~.mwn n~.mmvm.mm an.oonvs.o~n Am.aevm.cm Ao.onvfl.qe an.~¢vc.mm Am.h¢~vn.mem deuce
Ao.m~vu.mm A<.n~vo.m~ Ac.c~vx.oH Aq.m~v~.- an.-vm.~s Aa.0qve.w~ Am.<v¢.m Am.cv~.- An.mdvn.o~ Ao.~nvw.on avononoo Hooch
Ao.nv~.n Ao.nv¢.n Aeo.vm.n Am.mvo.c Ac.~vm.~ Au.cvn.m A-.vm.~ Ao.~v¢.~ Ae.nvu.n An.ev~.o «amaze:
Ao.mvm.w AH.~HVQ.- Am.q~vm.m A~.-vn.- A~.~vn.o Ao.cuvm.ma An.vm.n Ao.~vm.N Aw.~vn.c An.muvc.n~ nmNurkma .b uu5v<
Am.-vm.o~ Ad.m~vo.- Ao.o_vo.- A~.-vm.q~ Am.mvc.o Aa.cnv¢.~N Amo.vm.m Ac.Hv¢.o Ac.o~v~.mfi Ao.n¢vn.o~ uvcnonoo u~3v<
Aq.vm.~ Ao.mVo.~ Amo.va.m A_.qV~.m Am.mvm.~ ad.ovn.o~ Amm.vNH. Ac.Hv~.¢ Aa.an.~ Aa.evn.- .nm Ufimsoom
Aw.nvn.mn Ao.mva.- A~.qmv_.mm Acvo.o~ Aw.wvm.wm Am.mm~vm.mc Ao.cv¢.oH onn.m Am.ovn.~¢ Am.nsuvc.mm .nm Ufib}¢x~
A~.wv¢.eq Ac.o~vo.¢~ Ao.~nvo.mm Am.qV~.q~ Ao.~ch.nc Am.me~vm.ms Ao.~v~.ue Aa.cvo.mu An.nde.¢o Aw.~m~vo.¢a auouovumo
Am.nVc.~H Am.ov¢.a~ Am.mvc.n Ao.-vm.fia An.ov~.oA Ao.-vc.mm Am.nvm.n An.-v¢.oa An.muvm.mu «Aa.~avn.¢~ muouuuoz
whoa emoa who" shay m~o~ onm~ whoa «nod whom chad mxmh
«a

 

.m~m~ can «Boa cu Anonua\m:v macaumnm Ham um acuxcmHQOON uo nauseaa dances com: .0

wanmh

I37

. mucosa: no: use 3:03.33?

 

 

NH

ma

2

Amn.voa. Ann.vmn. ANa.vsm. An~.omn. AH~.voe. Aa~.van. AN.HVnm. Aod.von. Ao~.vnn. Ada.oan. dance
Ama.v~a. Amn.oonv Aa.HVoa. Ane.vom. Aeo.vnn. Am~.8nn. Aa.uvan. Aau.vae. Auh.vaa. Aao.voo. avoaoaoo Annoy
Asa.omd. Aan.oao. AHH.V-. An~.v~1. AeH.oa~. Amc.8H~. .Hu.vn~. AoH.VH~. Asu.v~. Aac.v-. «Adana:
Ae.~86.n Aq.nvfi.n Ag.noo.fi Ae.~8~.n RN.~Vo.~ Am.~vm.n Ao.nvn.n Ao.~oa.~ An.NVn.e A~.nvh.n amnexgma .o.u~=u<
A~.n8~.n Ao.nvn.n Am.¢oa.n Ae.~vo.m As.ovn.¢ “n.68s.q Au.nv~.n Ao.~vo.~ Ao.nv~.e An.nvn.e avoaoaoo uH=u<
Ae.ona. an.~oo. A~q.v~.n 11.81. Ame.8H.A An.oa. ANo.8q~. A~.Vn. Aua.vem. an.va. .ao newsman
Am.~8a.na an.n8~.c Am.wavo.~m goon.o Ac.evs.o A~.o~8q.m “can.c ono.AH Ao.ev~.o AA.HA8n.a .au acreage
An.eoo.n Am.~8H.H Aa.nfiog.o As.ve.a an.~8m.n An.mva.~ Am.vm.h An.vn.fi A~.Hvo.s Ao.ovc.n uuouoeafio
AoA.om~. AAH.VAA. Ago.onn. AA~.8HH. Aao.vao. Aho.v.fi RA~.8~H. Aao.vmg. Aso.vmo. «Aac.vma. announce
Agog shod mgan smog shad shad mama «Asa naod Quad anus

.mnau v:- za .5 Away Huavufinvczouuu Nassau coo: .OH macaw

38

with little trend in the mean size. The consistent, depressed abundances
found in station 18 and 12 comparisons were not as apparent in 1975, but
there were some species—related trends (Table 8). Analysis of biomass
at these stations demonstrated a decrease in 50% of the major taxa and
an increase in the remaining groups resulting in almost parallel size
changes (Tables 9, 10). Rotifera and Cladocera decreased in total bio-
mass and increased in mean size during passage from the intake to the
upper discharge, while Cyclops vernalis decreased in both mean size and
total biomass. Mean annual densities between the upper and lower dis-
charge stations appeared to be somewhat similar. However, there was a
minor net increase in numbers of certain species as they traveled
through the discharge canal (Table 8), and in several taxa there was a
decrease in total biomass and a corresponding reduction in mean size
(Cladocera, Daphnia sp., Bosmina sp., adult Copepoda and nauplii).
Regression values based on afternoon and evening cladoceran and
copepod distributions indicated no significant diurnal, vertical migra-
tions; nor was there any real evidence of depth-related distributions
(Figures l6-—19). Patchy distributions of zooplankton and the lack of
the intense sampling needed to quantify this variability may have been

the cause for these results.

Mortality

The data suggest that lethal temperatures for many of the copepods
and cladocerans were reached on August 2, 3 and hth, 1975 (Table 11). On
August 2nd, the temperature in the upper discharge was 38°C and mortali-
ties averaged 76% among the three replicate samples, while intake mor—
talities averaged only 12%. These percentages seemed to decrease as a

function of temperature in the upper discharge and on August 3rd and hth,

39

 

 

 

 

 

 

on A n A
II-
2.. ‘ e 1r=-.79 “A ‘r='-I3
3-ICI A Ir= .18 .M It‘=-.IO
4.. .‘ A At“= .40 h Or: .27
5. or=-.33 or: '55
6 I em 1 __1 - Q 1 4
I00 200 300 I00 200 300
g Station I7 Station 9
E I a e
8 n A
= .54
-AiA ::= .36 AD ::: .2731
"' fl or= .72 n A ar: .08
.. or = -.82 '
or = -.38
~00 {I . 1. I q to . 3
I00 200 300 I00 200 300
Station I2 Station 8

June I974

Figure 16. Mean densities (no./1iter) of copepods (A = afternoon;
U= evening) and cladocerans (A= afternoon; I = evening)
at all depths and regression values based on the density
of each group at a particular depth in June 197k.

hO

 

 

 

 

O D A A
I
2 D A A U
3 DA A r = 0 AB A? = 61
A 1 r = .41 0 Ir = .61
4 D or = -.74 4” = -.63
5 or = .46 DY‘ = -.28
6 .0 a 1. A . . 3
IOO 200 300 I00 200 300
.5 Station I7 Station 9
'3 I A u A n
2
(5‘3 4; c]
or = 0 Ar = ”2
m .r=-.66 D A er= .75
D A or = .65 A M = .52
or = .55 or = -.22
1 I A] D . IA 01 9
I00 200 300 I00 .200 300
Station l2 SIOIIOI’I 8

August I974

Figure 17. Mean densities (no./1iter) of c0pepods (A = afternoon;
C) = evening) and cladocerans (A = afternoon; I = evening)
at all depths and regression values based on the density
of each group at a particular depth in August 197A.

hl

 

 

 

 

0 D
I _
1r= -.09 er= -.IO
2 9“ 1r: .27 ”A er= .88
3 e or= .15 AI": .23
4 an org-.47 “A n or= .86
5
6 b 1 1 4 “10 1 J
I00 200 300 I00 200 300
3 Station I7 SIOIIOI‘I 9
d)
5 6 a
E
or= .76 ar= .87
BA It‘=-.52 U A Ir= .06
A or = -.05 AD or = .31
An 0" = --76 BA or = -.69
A‘l 1 J 4 I 4
I00 200 300 I00 200 300
Station I2 Station 8

July I975

Figure 18. Mean densities (no./liter) of copepods (A = afternoon;
D = evening) and cladocerans (A = afternoon; . = evening)
at all depths and regression values based on the density
of each group at a particular depth in July 1975.

GUI-bUN—O

Meters

Figure 19.

 

 

 

:IAA
- or = .70
.3 ‘5 or = .38
36 - or = -.05
.m or = .07
.01. 1 j
IOO 200 300
Station I7
A
A r = .39
no I r = .10
Ar = .34
a r = .93
8
an 1 I
I00 200 300
Statian|2

h2

D
u
c:

-.61

D
u
c:

 

I00 200 300

 

 

Station 9
P a
-6‘0 or = .96
or = .81
3 .'.'I& or = .20
IA. or = -.15
'5' ‘. 4
I00 200 300
Station8

September I975

Mean densities (no./liter) of copepods (A = afternoon;
[3 = evening) and cladocerans (A = afternoon; I= evening)
at all depths and regression values based on the density
of each group at a particular depth in September 1975.

M3

.hww meow one no most> Honda owawnomfic mpocou mHmonpcohwm :H muonsszm
.onEwmQSm pmpHHIH w :H endow deSHcm HHw wcH>pompo an @oaHahmpoc who: mmpwh thprhozH

 

 

 

 

I o I o I e .mm oxmsmom
I o I o I H .mm esoooao£mawq
I o I o I H .mm aaosmanmmgm
I o I o I H kuwamx aaowoumoq
Ammvo Amvo Aqva .mm mmoNomU
AQOHVOH Azgmv: onqm coaxooauoa awsfimdm
Hm m.me e.m om Am.ov Awmvm.mm ma mHaaam mxwpeH
V.
80:0 30 lo: .8 Sasmomm
I On I H I H .mm usomoraxaava.s
I o I o I m wwuwawx aaowoummnn+
Acmvo AHvo AHVNN .mm maoNomuhc
Ammva AHmHVm HHvzn aaaxooauoa awaameQTL
6
HQ m.we e.m om Am.ov Awmvm.wm ma mHaswm agapeHnm
Awwvo szo ANVH .mm ostmom
I o I o I : .am asomoroxmowa
AOOHVO Amvo loam cognate unseenamq
Homvom AmVH Amvm .mm mxsocmawm
Ammvw AOHVH vazH .mm mmoNomu
Amovmm AmHvzH thw: coaxooauoa awaxmam
Hm m.me e.m om Am.ov mAwmvm.wm Ha mHaswm meapeH
3&5 sake 3.2% tan: Ems as
wwawnomHm pmpwz nopwz & comm m>HH< voHQEdm Hdschom ohdpwuomsma
pr09 oqu ho>Hm thHmphoz amnfidz hmnadz H®E5H0> ocHuOHno hopes

 

.mcwgooouwHo can mwommmoo qu>Ho>qH modem thprnoe and omnnp a mo mpHdmom .HH oHan

.mde man so oxdqu map wGHHmadm wopwnwsonm hospwo3 pnoaoHocHx

 

 

MI

 

 

00H 2 0 .mm gmsmom
m: m H .mm asowgmonfi
o o H «33$ 28038
OOH H. O .Qm wgofinmda
em NH mm .mm omoNomb
m a m w 983.03% mm UHSEQSQ
Hm m.>e H.m om Am.ov o.mm ma deEam mmHenomHm
"V
E m H .8 Sasmomm
mm m m .3 gomggmag m...
mm H m Hanweax ensconamq
o o H .mm mxsoomonfiwc
mm N :w .3 mmoNomb T.
mm m H HH agooauoa Uganda %
Hm m.ee H.m om Am.ov o.mm ma «Haswm mewnomHm
S. OH m .3. 65$QO
mm OH w .3 Eggnog
a. m H etude 28833
o o H .mm mgoumoa
mm NH Hm .HHm oQoNomb
3. mm m egocauoa SSEGQ
Hm m.»e H.m om Am.ov o.wm Ha mHaamm mmaenomHn
Aoom\msv Aoom\mav Aoom\mev AmnopHHv Aime: Aoov
ompwnomwm .8me Hope: we boom 95:. UonEdm HwSUHmom ohdpwhomSoB
proe oxdq po>Hm szprpoz hopadz hopssz oESHo> onHMOHno nova:

H

A.e.p:oov HH opre

MS

 

 

 

 

ono ono AHVm .mm aawsoom
8:8 EH 3H .8 esomoefiafia
I o I o I H .mm mzsoumawm
vao Amvo AmmeH .mm mmoNomU
I o I o I PH coaxooanoa awrxmam
Hm m.~e H.m om on Am.omvo.mm ma mHgawm mxwch
80:- 3. 8V- .9... Sasmomw
330 A30 AmVH .mm osomoroxmaufim
I o I o I H «ENBASN daowoamouq
I o I o I H .mm mxsoamommuw
vao Amvo Azmvmm .mm mmoNoAuTL
Ammvo Amvo Amv: aaaxooauoa awxxasmmw
Hm m.»e H.m om on Am.omvo.wm ma mHaawm mHmpeHrs
AOOHvo AHVo AoVH .mm esoooxaamowm
ono Hove AHVH «wuwawx aaowoamoq
I o I o I m .mm mxsoumowm
AmHvo Amvo AMHVMH .mm mmoNomb
AmFVH AmvH AHVm uaazooaaoa awxxmam
Hm m.>> H.m om on Am.omvo.mm H§ mHQSdm wxdpGH
Aoom\mfiv Aoom\mev Aoom\mev AmhopHHv AH\wEv Aoov
mwawnomHQ pope: hope: & doom o>HH< oonswm szchom oHSHwHoQEoB
Hence oqu nm>Hm thHmpaoz nonadz popadz mESHo> maHHOHno Hope:

 

A.e.pcoov HH mHnme

h6

at temperatures of 36 and 30.500, the respective mortalities were h8 and
h0%. Results of this study demonstrated that more cladocerans than cope-
pods were killed after cooling system passage. Studies conducted in 1976
on the largest zooplankter, Leptodbra kindtii, showed an average of 60%
of these organisms were killed by passage through the plant; possibly

because of mechanical factors (Table 12).

Diversity

Entrainment through the plant cooling system appeared to have little
effect on zooplankton diversity (Table 13). The index used was influ-
enced by the numbers of species found during the most productive months
of the study and demonstrated that no major changes occurred from station
to station during both years. There were also no consistent trends in
diversity related to time of day. Afternoon and evening indices at each
station showed minor variations, but this could have been attributed to
spatial variability among samples collected from patchy zooplankton dis-

tributions.

h?

 

P.
omhmnomHQ m.

 

 

 

 

cm emu; 0mm; so. 0.0m 0.: 0.: A
penance
a
w HP 0mm 0.:m >.: m.mm w.MH mxdchmfl
P.
R mom m3 mo. 9mm 0... 0;.» mwfinomHom
mommofi
IL
. . . a
mm mwm Ham H 0 am m m N om m wH oxwpaHmw
. or
é mmHm mam mo. o.mm o.m 0.: mmaenomHmm.
nommbfi
o/
TL
0 o ammuH 03m 0.: 11mm m.mH oxapfiw
o/
AH\wEV Aoov Amev Hoom\mev Aomm\m8v Aomm\mav
& comm o>HH< stvamm manpwaomEoB voH saw mwumnomHQ popes hopmz
huHHapaoE amnssz nonazz ochOHno amps: oESHo> Hmpoe oqu nm>Hm
.mpmH :H wwuhrwx aaomoumou mo zwzpm thpr905 amp monnp a mo mpHsmom .mH oHnt

h8

Table 13. Diversity index values for zooplankton taxa captured in the
cooling system. Diversity was calculated by:

 

 

7
*_S.+¢
H - -2 (NJ /N )lole(NJ/N)
J=l
1973 17 9 18 12 8
6/11 .53 .59 .53 .57 .59
6/12 .70 .51 .59 .73 .78
8/8 .h2 .u9 .h5 .50 .h3
8/9 .ua .69 .6h .h0 .h5
9/28 .8h .76 .92 .87 .95
9/29 .81 .83 .83 .93 .96
197k
6/11 .98 1.08 1.00 .81 1.00
6/12 .70 1.08 .78 .9h .9h
8/1h .63 .9h .67 .92 .82
8/15 .51 .90 .5h .72 .81
10/19 .66 .6h .66 .67 .67
10/21 .7h .60 .73 .65 .67
1975
5/16 .59 .80 .67 .62 .8h
5/17 .55 .78 .67 .76 .68
7/27 .72 .99 .73 .87 .80
7/28 .81 .92 .82 1.06 1.00
9/15 1.01 .59 .95 .9h 1.00
9/16 .91 .89 .91 1.10 .86
* = Diversity
8 = Number of Species

+I~
II

Total Abundance

_;.
ll

Abundance of Each Species

DISCUSSION

impact of Cooling System Passage

 

Analysis of the data in this study reveals many similarities to a
1972-73 investigation conducted by Simons (1977) when the plant had only
two to three units functioning sporadically (Appendix B). Basically,
the same materials and methods were used by Simons (1977) to demonstrate
that short-term abundances (afternoon/evening) also varied less than
those over the entire year, and that biomass and size showed only
slight, short-term temporal differences. The evening samples, as in
l97h-75, had the greatest biomass and size. Simons (1977) also found
that chlorine applications had no measured impact on plankton numbers
and biomass, but that the mean concentrations of organisms decreased sig-
nificantly in passage from the intake to the upper discharge canal. The
earlier study showed decreases in zooplankton size and an increase in
numbers/liter as the plankton passed down the discharge canal from sta-
tion 12 to station 8. This was also apparent in the present investiga-
tions. Diversity indices calculated in 1972—73 were similar to those of
this study, while the mortality percentages differed substantially (pos-
sibly because the plant was not at full capacity during this period).

Examination of the mean annual densities of all major taxonomic
zooplankton groups indicate that from November 1972 to September 1975,
an average of 31% of the total number of animals disappeared from the
water column between intake station 18 and upper discharge station 12.

Entrainment through the plant and the resulting decreased abundances

“9

50

were not size-related in most cases. Although these declines seem to be
consistent indicators of impact at the Monroe Power Plant, this result
appears to be unusual when compared to the results obtained at other
power plants. Carpenter et_§l, (197h) and Heinle (1976) report signifi—
cant population losses in discharge areas, but at reference points down-
stream from the immediate source of the effluent.

The reductions in mean annual densities in the upper discharge
canal may be caused by one or a combination of several factors. The
apparent changes could have been caused by under- or overestimating the
ratios of the cooling water sources and their respective biological com-
position in calculating intake station 18. However, USGS records of the
Raisin River flow and plant pumping rates, used in conjunction with the
chloride tracing, demonstrate that the mean annual calculated proportions
of intake stations 17 and 9 (=station 18) were accurately estimated.

Between the intake and the upper discharge canal zooplankton pass
through pumps and condensers at about 2 m/sec, then through the concrete
overflow canal at about 0.75 m/sec. The losses that occurred and the
mechanisms that caused them were realized before the water reached the
upstream discharge station. Organisms may have been mechanically de-
stroyed by the pressures and turbulence experienced in pump and condenser
passage. Possible fish predators have never been sampled in the concrete
conduit, but Cole (1976a) indicated that water velocities seemed too
high (1 m/sec) and the canal too short to maintain large enough numbers
of fish to have such an important impact.

Variations in 200p1ankton densities between times when the water
was chlorinated and times when it was not chlorinated are not great

enough to suspect chlorine as a major influence. Furthermore, even

51
though chlorine may have been killing the animals, their carcasses would
not have been destroyed by the chemical.

By the time water from the overflow canal (conduit) reached the up-
stream discharge station, dead or stunned organisms may have begun to
settle out of the water column. Stavn (1971), while experimenting with
Langmuir circulations and Daphnia distributions, showed that dead ani-
mals introduced to 30.5-cm deep chambers with currents of 2.0—8.8 cm/sec,
sank to the bottom within a minute.

It is also possible that some of the more active zooplankters swam
toward the bottom when they first entered the discharge canal. McLaren
(1963) and Gehrs (l97h) reported that certain species moved downward when
they were exposed to higher temperatures. In waters of minimal turbu-
lence, the copepods with swimming speeds up to 30 cm/sec (Allan, 1976)
could accomplish this type of movement in the upper discharge canal.

In this case the grouping of zooplankton below regular sampling depths
would create a loss that was not real.

As the zooplankton moved down the discharge canal to station 8,
there was little change in mean annual densities. However, there were
obvious changes in the mean size of some taxa, especially the clado-
cerans and rotifers, which showed respective decreases and increases.
Aside from the possibilities of settling out, emigrating from the water
column, or size-related mortalities, predation could have caused the
decrease in cladoceran size and a subsequent increase in the size of
the rotifers. Brooks and Dodson (1965) indicate that intense predation
will eliminate the larger species enabling the smaller types to pre-
dominate. Additionally, it was found that concentrations of fish in

the discharge canal may have exceeded the seasonal mean density in the

52
open lake by 10 times or more (Cole, 1976b) and that certain fish species
caught in the vicinity of the power plant tended to be size-selective
feeders (Kenaga and Cole, 1975). The mean size of nauplii and adult
copepods did not fluctuate in a consistent pattern during passage, per-
haps because of a uniformity of size among the individuals observed in
the samples.

If the Monroe Power Plant had the greatest effect on the larger
zooplankters, it was not apparent in the diversity indices. Since the
formula used was influenced heavily by the total number of species,
several taxa would have to be eliminated to detect a measurable impact
by the plant.

Several explanations could be possible for the slight increase in
mean annual densities which occurred as the zooplankton passed through
the cooling system to station 8. If the organisms were not seriously
injured after plant passage, increased reproduction could have resulted
in the heated waters of the discharge canal. Allan (1976) reported that
in the Rotifera, 1.25-1.75 days are required to go from egg to egg at
250C, and 7—8 days for the Copepoda and Cladocera. It was also stated
that during a lifetime of 5 days at this temperature, rotifers could
produce a total of 15-25 offspring, while copepods and cladocerans
generally produced 500-750 young in a ho-day lifetime. In the few hours
it takes for the effluent and organisms to travel downstream, the impact
of new smaller individuals upon the existing populations was probably
not of great importance, but could have contributed slightly to a reduc-
tion in mean sizes. Increases in densities also may have resulted from
the reorientation in the water column of recovered injured or shocked

organisms which had settled out upstream. Vertical profiles constructed

53

in the 1972-73 study indicate that the copepods and cladocerans had re-
positioned along depth-related gradients within a few hours after plant

passage.

Mortality

The most tangible evidence that once-through cooling affects plank—
ton was derived from the short-term mortality investigations. Many
authors have indicated that the effects of suddent temperature changes,
mechanical stresses and chlorine applications separately or together can
be lethal to zooplankton. Coutant (1970) and Storr (l97h) report heat-
related deaths of 80 and 100% at ho and h0.50C, while Restaino §t_§l,
(1975), Benda and Gulvas (1976), and Carpenter gt_al, (197A) attribute
respective mortalities of 15, 31 and 70% to mechanical stress. Direct
mortalities caused by chlorine in the absence of temperature rise and
mechanical stresses (condenser passage) are difficult to detect in the
field; however, Heinle (1976) found that the percentage of living zoo-
plankton collected during chlorination was reduced by some 60%. Exten-
sive laboratory work reviewed by Brungs (1973) suggests that the total
residual chlorine level in receiving waters should be 2 ppb or less for
most aquatic organisms.

For most of the taxa collected at the Monroe Power Plant the temper-
ature rise above ambient waters experienced in the condenser appeared to
cause the greatest stress. None of the dead copepods or cladocerans
examined during the 1975 mortality study showed signs of mechanical in-
Juries and even though they were collected at the time the plant was
chlorinating, no trace of the chemical was measured in the upper dis-
charge area. The 76% mortality incurred at 38°C in the upper discharge

canal seems to agree with Coutant and Starr's findings. In June 197A,

5h

Simons found the average mortality among copepods and cladocerans to be
only 16.5% at a lower temperature of 290C in the upper discharge canal,
while in both years the intake dead averaged about 12.5%. That the
mortality in l97h and 1975 was taxon-selective, being especially high in
the Cladocera, is also apparent in observations made by other researchers
(Miller 9331., 1976).

Although temperature had the greatest impact on most of the zoo-
plankton, one species, Leptodbra kindtii, suffered mechanical damage as
well. Many of the specimens observed in the outfall area in 1976 were
mangled, suggesting that pump and condenser passage may have been the
cause. Since this organism is exceptionally large relative to the
others, it appears to be influenced more by plant passage. Kenaga and
Cole (1975) found that Juvenile fish over 30 mm long selected L. kindtii
as a preferred food item in the study area pointing out its importance as
a forage species. Because the plant affects some of the zooplankton more
than others, it may be viewed as an artificial predator in competition
for specific types of organisms.

In summary, there is evidence that entrainment of zooplankton at
the Monroe Power Plant affects their mean densities, mean sizes, dis-
tributions andnmutality. Certain organisms decreased in number by nearly
half before reaching the upper discharge station and decreased in size
and increased slightly in density as they traveled down the discharge
canal. 0n the site mortality studies revealed extensive deaths among
the Cladocera, particularly Leptodbra kindtii, during the hotter part of
the year due to combined heat and mechanical stresses. hFor most of the
species involved, however, the impact of the plant on total zooplankton

may be outweighed by the productive nature of the western basin of Lake

55

Erie. Cole (1976a) estimated that even if all the zooplankton were
killed during plant passage, the residual populations in this small part
of the basin could turn over at least 2 to h times in the summer months
based on a 2 to A week lifetime. But it should be emphasized that even
though the waters surrounding the Monroe Power Plant are extremely pro-
ductive, the biota they contain should not be considered inexhaustible.
Some form of continuous monitoring should be required at the Monroe
Power Plant to insure that the impact it has on receiving and discharge
waters is not going to lead to damaging losses of any part of the aquatic

community.

LITERATURE CITED

Allan, D. J. 1976. Life history patterns in zooplankton. Amer. Nat.
110(971):165—180.

Benda, R. S. and J. Gulvas. 1976. Effects of the Palisades Nuclear
Power Plant on Lake Michigan. In_Thermal Ecology II. Proceedings
of a symposium held at Augusta, Georgia, April 2-5, 1975, pp. 2A3-
250.

Brooks, J. L. 1965. Predation, body size and composition of plankton.
Science 150:28-35.

Brungs, W. A. 1973. Effects of residual chlorine on aquatic life. J.
Water Poll. Contr. Fed. h5(10):2180-2193.

Cairns, J. 1971. Thermal pollution - a cause for concern. J. Water
Poll. Contr. Fed. h3(l):55-65.

Carpenter, E. S., B. B. Peck and S. J. Anderson. 197A. Survival of
COpepods passing through a nuclear power station on northeastern
Long Island Sound, U.S.A., Marine Bio. 2hzh9-55.

Cole, R. A. 1976a. Entrainment at a once-through cooling system on
western Lake Erie. Report to the Office of Research Development,
U.S. Environmental Protection Agency, 165 pp.

Cole, R. A. 1976b. The impact of thermal discharge from the Monroe
Power Plant on the aquatic community in western Lake Erie. Tech-
nical Report 32.6, Institute of Water Research, Michigan State Uni-
versity, East Lansing, Michigan, 571 pp.

Coutant, C. C. 1970. Biological aspects of thermal pollution. I. En-
trainment and discharge canal effects. CRC Crit. Rev. Environ.
Contr. 1(3):3h1-381.

Cummins, K. W. and J. C. WUycheck. 1971. Caloric equivalents for in-
vestigations in ecological energetics. Int. Ass. of Theor. and
Appl. Limnol., Pub. No. 18, 158 pp.

Davies, R. M. and L. D. Jensen. 197M. Effects of entrainment on zoo-

plankton at three mid-Atlantic Power Plants, Report No. 10, Electric
Power Research Institute, 76 pp.

56

57

Gehrs, C. W. 197h. Vertical movement of zooplankton in response to
heated water. In_Thermal Ecology. Proceedings of a symposium held
in Augusta, Georgia, May 3-5, 1973, pp. 285—290.

Heinle, D. R. 1976. Effects of passage through power plant cooling
systems on estuarine c0pepods. Environ. Pollut. 2(1):39-57.

Kenaga, D. E. and R. A. Cole. 1975. Food selection and feeding rela—
tionships of yellow perch Perca flavescens (Mitchell), white bass
Mbrone chrysops (Rafinesque) and goldfish Carassius auratus (Lin-
neaus) in western Lake Erie. Technical Report No. 32.5, Institute
of Water Research, Michigan State University, East Lansing, Michigan,
61 pp.

McLaren, I. A. 1963. Effects of temperature on growth of zooplankton,
and adaptive value of vertical migration. J. Fish. Res. Ed. Can.

20(3):685-727.

Miller, M. c., a. R. Hater, T. w. Federle and J. Reed. 1976. Effects of
power plant operation on the biota of a thermal discharge channel.
I§_Thermal Ecology II. Proceedings of a symposium held at Augusta,
Georgia, April 2-5, 1975, pp. 251-258.

Pielou, E. C. 1969. An_Introduction tg_Mathematical Ecology. Wiley,
New York, 286 pp.

 

 

Restaino, A. L., D. G. Redmond and R. Otto. 1975. Entrainment study at
Zion station. I2_Effects of 210 Station Operation on the Biota in
Southwestern Lake Michigan, pp. 1-55.

Simons, M. 1977. Entrainment of zooplankton into a once-through cooling
system on western Lake Erie. M.S. Thesis, Michigan State University,
East Lansing.

Sokal, R. R. and F. J. Rohlf. 1969. Biometry. W. H. Freeman and Co.,
San Francisco, California, 776 pp.

Stavn, R. H. 1971. Hypothesis: Langmuir circulations and Daphnia dis-
tributions. Limnol. and Oceanogr. l6(2):h53-h66.

Storr, J. F. l97h. Plankton entrainment by the condenser systems of
nuclear power stations on Lake Ontario. In_Therma1 Ecology. Pro-
ceedings of a symposium held in Augusta, Georgia, May 3-5, 1973,
pp. 291-295.

Weast, R. 0., Ed. 1968. Handbook of chemistry and physics. h9th ed.
Chemical Rubber 00., Cleveland, Ohio, 2300 pp.

APPENDI CES

APPENDIX A

58

Table A1. Zooplanktonic distribution (no./liter) in the cooling system
(mean of five replicates).

 

 

Station
Species 17 9 12 8
12/12/73 (Night)
KarateZZa cochlearis 0.5 0 2 - O 2
KarateZZa earlinae 6.0 - - —
Karatella quadrata h.5 0.5 2.0 1.0
Briochionus calycifiorus 8.0 1.5 - -
Synchaeta sp . h . 5 h . O - -
Pblyarthra sp. 8.5 2.0 - -
KeZZicottia Zongispina 0.5 - - -
Bosmina sp. h.5 l 0 - 0 2
Chydbrus sphaericus 0.5 - - -
cyclops bicuspidatus - 1.5 — —
cyclops vernalis - l O - -
Immature cyclopoids 2 0 - l 0 0.5
Nauplii 5 5 3.0 l 0 2.5
12/13/73 (Afternoon)
KarateZZa cochlearis 1.5 8.0 2 5 2.0
Karatella earlinae 6.5 5.5 - -
KarateZZa quadrata 2.0 1.5 - -
Brachionus calyciflorus 2.5 1.0 1 0 0.5
synchaeta sp. 12.0 8.0 - 0.5
Pblyarthra sp. 3.5 11.0 2 0 1.0
Filinia Zongiseta - 1.0 - —
Asplanchna sp. - - 1.5 -
Bosmina sp. 2.0 - - 2.0
Chydbrus sphaericus 0.5 - 0.5 -
cyclops vernalis 2.5 - - -
Immature cyclopoids 2.5 1.0 2.0 0.5
Nauplii 7.5 8.0 1.5 0.5
01/31/7h (Night)
KarateZZa cochlearis - 0.5 - 0.5
Karatella quadrata 1.0 - 1.0 1.0
Karatella earZinae - — — 0.5
Brachionus calyciflorus 1.0 0.5 - 0.5
Brachionus urceolaris - - 15.0 -
Brachionus quadridentata - — - 0 5
Brachionus angularis - 0.5 - -
synchaeta sp. - 1.5 - 0.5
Pbearthra sp. 3.0 2 O - 0.5

Asplanchna sp. - L 15.0 -

Table A1 (cont'd.)

59

 

Species

17

Station

12

 

01/31/7h (Night) (cont'd.)

Notholca sp.
Bosmina sp.
Chydorus sphaericus
Immature cyclopoids
Nauplii

O2/l/7h (Afternoon)

KarateZZa cochlearis
KarateZZa quadrata
Brachionus calycionrus
synchaeta sp.
Pblyarthra sp.
Nitholea sp.
KeZZicottia Zongispina
Rotaria neptunia
Bosmina sp.

Daphnia retrocurva
cyclops bicuspidatus
cyclops vernalis
Immature cyclopoids
Nauplii

0h/07/7h (Night)

KarateZZa quadrata
Brachionue calycifiorus
Brachionus urceolaris
Brachionus angularis
Pbearthra sp.

Filinia longiseta
AspZanchna sp.

Notho an sp .
KeZZicottia longispina
Cephalodélla sp.
cyclops vernalis
Diaptomus ashZandi
Immature cyclopoids
Nauplii

OOO
\J‘IU1U'1

OOO
\J‘IU'IU'I

2.0

15.0

No
\J'IU'I

I—‘O
O\J'I

000
WWW

WI—‘Ol-‘O
OOUIOU'I

MOI-'00
OWWUIW

Table A1 (cont'd.)

6O

 

Species

17

Station
12

 

Oh/08/7h (Afternoon)

Karatella quadrata
Brachionus calycifiorus
Brachionus urceoZaris
Brachionus caudatus
Brachionus sp.
synchaeta sp.

Filinia Zongiseta
Netholca sp.
Euchlanis sp.
Gastropus sp.

cyclops bicuspidntus
Diaptomus ashlandi
Immature cyclopoids
Nauplii

06/11/7h (Night)

KarateZZa cochlearis
KarateZZa quadrata
KarateZZa earlinae
Brachionus calycifioris
Brachionus angularis
Brachionus caudatus
Brachionus havanaensis
Brachionus budapestinensis
Synchaeta sp.
Pbearthra sp.
AspZanchna sp.
KeZZicottia longispina
Trichocerca sp.
Cbnochilus sp.

Bosmina sp.

Daphnia retrocurva
Daphnia galeata mendbtae
Diaphanosoma sp.
Leptodbra kindtii
Immature daphnia sp.
Cyclops bicuspidatus
Cyclops vernalis
Immature cyclopoids
Diaptomus ashlandi
Diaptomus siciloides
Immature calanoids
Nauplii

I—‘OO
OUIU'I

NCDJ'I‘
000

CD I-J I-‘IU
4:“0\O mooox
GOO 000

1.0

1:”?
OO

12" mm
00

O

F‘FJ
03 arcrcnar:rn)
c>c>c>c>c>c>

ON
0

61

Table A1 (cont'd.)

 

Station
Species 17 9

 

06/12/7h (Afternoon)

KarateZZa cochlearis h.0 h.0
Karatella quadrata h 0
Brachionus calycifloris - 8
Brachionus angularis 2.0 20
Brachionus havanaensis - 16.
Brachionus urceoZaris - 8
synchaeta sp. - —
Polyarthra sp. 12.0 12.0
Asplanchna sp. - 12.0
Filinia Zongiseta - 6.0
Kellicottia Zongispina - -
Trichocerca sp.
Cbnochilus sp.
Lecane sp.
Bosmina sp. 5
Daphnia retrocurva 8 .
Chydbrus sphaericus -
Diaphanosoma sp. -
Leptodbra kindtii 2.0 -
Cbriodaphnia sp. — -
cyclops bicuspidatus h.0 2.0
Cyclops vernalis 12.0 10.0 .
Immature cyclopoids 12.0 - l .
Diaptomus ashlandi - -
Diaptomus sicilis - -
Immature calanoids - - .
Nauplii 160.0 6h.O 8 .

08/1h/7h (Night)

KarateZZa cochelaris 8.0 36.
Karatella quadrata - 2
KarateZZa earZinae h.0 -
Brachionus calycifiorus - 32.
Brachionus angularis 60.0 60.
Brachionus caudatus - 50.
Brachionus havanaensis - 6.
Brachionus urceolaris - h.
Brachionus budnpestinensis 18.0 6.
synchaeta sp. 100.0 7h.
Pbearthra sp. - -
Asplanchna sp. -
Filinia Zongiseta -
Trichocerca sp. 56.0

OOOOOOO

l—’ h)
(DIOR)
000

0000000

Table A1 (cont'd.)

 

Species

Station

12

 

08/1u/7h (Night) (cont'd.)

Pompholyx sp.
Chromogaster sp.
Bosmina sp.

Chydbrus sphaericus
Cyclops bicuspidatus
Cyclops vernalis
Immature cyclopoids
Diaptomus siciloides
Eurytremora affinis
Immature calanoids
Nauplii

08/15/7h (Afternoon)

KarateZZa cochlearis
KarateZZa quadrata
KarateZZa earlinae
Karatella volga
Brachionus calycifiorus
Brachionus angularis
Brachionus caudatus
Brachionus havanaensis
Brachionus budhpestinensis
Brachionus quadridéntata
Synchaeta sp .
Pbearthra sp.
AspZanchna sp.
Trichocerca sp.
Pbmpholyx sp.
Chromogaster sp.
PZoesoma sp.

Gastropus sp.

Bosmina sp.

Daphnia retrocurva
Diaphanosoma sp.
Immature cyclopoids
Nauplii

l\)i\)l\)
000

042'
00

0000000000

NNN
000

5’?
CO

H
1:0er @0370

0000000

|._.I
‘1

(DID
00

mm
00

30.0

«IN
OOOOOO

I_.I
5.4
Jr'IUID-IT'IDO‘I O\O\C\O\Ok’

U.)
OOOOOO

Table A1 (cont'd.)

 

 

Station
Species 17 9 l2 8
10/19/7u (Night)
Karatella cochlearis 36.0 h.0 10.0 lh.0
Kératella quadrata 1h 0 2 0 8 0 1h.0
KarateZZa earlinae - - - 2.0
Brachionus calycionrus 32.0 10.0 h0.0 58 0
Brachionus havanaensis 2.0 - - -
synchaeta sp. 28h.0 118.0 196.0 370.0
Polyarthra sp. h2.0 10.0 12.0 h6.0
Asplanchna sp. 26 o 16.0 16.0 hh.0
Filinia Zongiseta - — - A O
Euchlanis sp. - - 2.0 -
Bosmina sp. 7h.0 32.0 52.0 96.0
Chydbrus sphaericus 1h.0 8.0 16 O 20.0
Diaphanosoma sp. - - - 2.0
Alana sp. 2 0 — - -
Cyclops vernalis - 2.0 6.0 h.0
Immature cyclopoids 6 O - 2.0 2.0
Eurytremora affinis - h.0 2.0 -
Immature calanoids - - - 8.0
Nauplii 10.0 10.0 8.0 16.0
lO/2l/7h (Afternoon)
Karatella cochlearis 3h.0 h.0 16.0 1h.0
KarateZZa quadrata 8.0 2.0 18.0 16.0
KarateZZa earlinae 12.0 - - 2.0
Brachionus calycifiorus hh.0 8.0 28.0 h6.0
Brachionus angularis - - h.0 -
synchaeta sp. 262.0 118.0 258.0 28h.0
Pbearthra sp. hh.0 6.0 3h.0 hh.0
AspZanchna sp. 3h.0 16.0 28.0 26.0
Trichocerca sp. 2.0 - 2.0 2.0
Chromogaster sp. 2.0 - - 2.0
Bosmina sp. 36.0 16.0 h8.0 52.0
Chydbrus sphaericus 3h.0 10.0 10 0 16.0
Cyclops vernalia 2.0 h.0 — 2.0
Immature cyclopoids 1h 0 - 6.0 -
Eurytremora affinis - 2.0 - -
Nauplii 26.0 16.0 16.0 10.0

Table A1 (cont'd.)

6h

 

Species

17

Station

12

 

Ol/2h/75 (Night)

Keratella cochlearis
Karatella quadrata
Karatella earlinae
Karatella hiemalis
Brachionus calyciflorus
Brachionus angularis
synchaeta sp.
Pblyarthra sp.
Asplanchna sp.
Notholca sp.
Kellicottia longispina
Aacomorpha sp.

Bosmina sp.

Alana sp.

Gariodaphnia sp.
Cyclops bicuspidatus
cyclops vernalis
Eurytremora affinis
Nauplii

01/25/75 (Afternoon)

Karatella cochlearis
Karatella quadrata
Karatella earlinae
Brachionus calyciflorus
Brachionus urceolaris
synchaeta sp.
Pblyarthra sp.
Asplanchna sp.
Kellicottia longispina
Rbtaria neptunia
Ascomorpha sp.

Beamina sp.

Mbcrothrix sp.

Cyclops bicuspidatus
cyclops vernalie
Diaptomus siciloidés
Diaptomus ashlandi
Diaptomus sicilis
Nauplii

UGO
OR)

Table A1 (cont'd.)

65

 

Species

Station

17 9

12

 

03/16/75 (Night)

Karatella cochlearis
Karatella quadrata
Karatella earlinae
Brachionus calyciflorus
Brachionus angularis
Brachionus caudatus
synchaeta sp.
Asplanchna sp.
Notholca sp.
Chromogaster sp.
Cyclops bicuspidatus
Cyclops vernalis
Immature cyclopoids
Diaptomus sicilis
Diaptomus minutus
Nauplii

03/15/75 (Afternoon)

Karatella cochlearis
Karatella quadrata
Brachionus calyciflorus
Brachionus angularis
synchaeta sp.
Notholca sp.
Chromogaster sp.
Cyclops bicuspidatus
Immature cyclopoids
Diqptomus ashlandi
Diaptomus minutus
Nauplii

05/16/75 (Night)

Karatella cochlearis
Karatella quadrata
Karatella earlinae
Brachionus calyciflorus
Brachionus angularis
Brachionus caudatus
Brachionus urceolaris
Brachionus quadridéntata
synchaeta sp.

I
@43wa
00000

mm
00
U1

Table A1 (cont'd.)

66

 

 

Station
Species 17 9 12 8
05/16/75 (Night) (cont'd.)
Polyarthra sp. 5.0 - - 2.0
Filinia longiseta 2.0 - - 1.0
Asplanchna sp. 1.0 - 1.0 2.0
Kellicottia longispina - 1.0 - -
Notholca sp. h.0 1 0 2.0 3.0
Daphnia retrocurva 1.0 - - 1.0
Chydorus sphaericus 2.0 - - -
Cyclops bicuspidotus - - 7.0 3.0
cyclops vernalis 1.0 - - 3.0
Immature cyclopoids l O 1 0 h.O 6.0
Diaptomus ashlandi - - - 1.0
Immature calanoids - - - 2.0
Nauplii 8.0 2.0 5.0 5.0
05/17/75 (Afternoon)
Karatella cochlearis 11.0 3.0 5.0 6.0
Karatella quadrata 17.0 5.0 h7.0 63.0
Karatella earlinae 1.0 - 1.0 1.0
Brachionus calyciflorus 27.0 2.0 33.0 23.0
Brachionus angularis 3.0 10.0 3.0 9.0
Brachionus urceolaris 7 0 1.0 1.0 1.0
Brachionus quadridentata - - 1.0 3.0
synchaeta sp. 165.0 h.O 68.0 35.0
Pblyarthra sp. 6.0 - 1.0 2.0
Filinia longiseta 2.0 1.0 3.0 1.0
Asplanchna sp. 3.0 1.0 2.0 -
Kellicottia longispina 1.0 - — —
Notholca sp. - - 3.0 1.0
Conochilus sp. 1.0 - - —
Ploesoma sp. - - 1.0 -
Bosmina sp. — - 1 0 -
Daphnia retrocurva 1 O - — -
Chydorus sphaericus - - 1 O -
cyclops bicuspidotus - — - l 0
Immature cyclopoids 2 O 2.0 - -
Diaptomus sp. - 1.0 - -
Nauplii 2.0 2.0 5.0 5.0
07/27/75 (Night)
Karatella cochlearis 98.0 8.0 no.0 58.0
Karatella valga 2.0 - - -

Table A1 (cont'd.)

 

Species

Station

12

 

07/27/75 (Night) (cont'd.)

Brachionus calyciflorus
Brachionus angularis
Brachionus caudotus
Brachionus havanaensis
Brachionus budopestinensis
synchaeta sp.
Polyarthra sp.

Asp lanchna sp .
Trichocerca sp.
Pbmpholyx sp.
Chromogaster sp.
Gastropus sp.

Bosmina sp.

Daphnia retrocurva
Diaphanosoma sp.
Leptodora kindtii
cyclops vernalis
Immature cyclopoids
Immature calanoids
Nauplii

07/28/75 (Afternoon)

Karatella cochlearis
Brachionus calyciflorus
Brachionus angularis
Brachionus caudotus
Brachionus havanaensis
Brachionus budopestinensis
synchaeta sp.

Polyarthra sp.

Asplanchna sp.

Filinia longiseta
Trichocerca sp.

Pompholyx sp.

Chromogaster sp.

Euchlanis sp.

Bosmina sp.

Daphnia retrocurva
Diaphanosoma sp.

Leptodbra kindtii

Immature Leptodbra kindtii
Cyclops vernalis

OOOOOOOO

F’ F40)
n)n>:‘03 z-anoro
c>c>c>c>

|\)
IOO-I?
COO
0000

H

Ir—Irmrox CDN-II‘
000

R)
00000
IU-II‘ON
000

0

(DJ? 43L" 4?
CO

I o
O O

F1 a:
CDRJO\N)N>N>OMO
c>c>c>c>c>c>c>c>

U.)

26.
10.

12.

00000000

O\-I="I\)
OOO

IU-P'm
OOO

MODCDOIUN
OOOOOO

H
000
DO

U.) l-'
O\O\I\)I\)
OOOO

Table A1 (cont'd.)

 

 

Station

Species 17 12 8
07/28/75 (Afternoon) (cont’d.)
Immature cyclopoids 2.0 12.0 h.O
Diaptomus sicilis - 2.0 —
Diaptomus ashlandi - - 2.0
Immature calanoids - 2.0 -
Nauplii 36.0 5h.o 6h.0
09/15/75 (Night)
Karatella cochlearis 20.0 3h 0 3h 0
Brachionus calyciflorus 2.0 — —
Brachionus angularis 32.0 1h.0 30 0
Brachionus caudatus - h.O —
Brachionus havanaensis 1h.0 10.0 8.0
synchaeta sp. 10.0 16.0 12.0
Polyarthra sp. 28.0 18.0 lh.0
Trichocerca sp. 12.0 h.O h.0
POmpholyx sp. lh.0 6.0 8.0
Chromogaster sp. 6.0 - 6.0
Bbtaria sp. - 2.0 2.0
Bosmina sp. 2 0 2.0 h.0
Chydorus sphaericus 26.0 12 0 16.0
Daphnia retrocurva 10.0 - 8.0
Daphnia galeata mendotae 2 0 _ -
Cyclops vernalis 2.0 h.0 h.0
Immature cyclopoids - 6.0 -
Diaptomus sp. - - 2.0
Immature calanoids h.0 2.0 2.0
Nauplii 20.0 36.0 36.0
09/16/75 (Afternoon)
Karatella cochlearis 76.0 22 O 12.0 16 0
Karatella earlinae - - 2.0 -
Brachionus calyciflorus - h.0 - -
Brachionus angularis 62.0 18.0 16.0 2h.0
Brachionus havanaensis - 6.0 18.0 20.0
Synchaeta sp. h0.0 10.0 1h.0 h.0
Polyarthra sp. h6.0 16.0 18.0 8.0
Asplanchna sp. - - 2.0 6. O
Trichocerca sp. 10.0 6.0 2.0 h.0
Pompholyx sp. 18.0 2.0 12.0 10.0
Chromogaster sp. 2.0 2.0 10.0 6.0

8.0 2.0 8.0

Bosmina sp.

Table A1 (cont'd.)

 

 

Station

Species 17 9 12 8

09/16/75 (Afternoon) (cont'd.)

Chydorus sphaericus 88.0 — 20.0 66.0
Daphnia retrocurva 18.0 - 6.0 10.0
Diaphanosoma sp. — 2.0 _ _

Leptodora kindtii 2.0 — 2.0 _

Cyclops bicuspidotus 2.0 - — —

Cyclops vernalis - - 2.0 -

Immature cyclopoids h.0 - h.0 2.0
Diaptomus siciloides - - 8.0 -

Diaptomus sicilis 2.0 - - -

Immature calanoids - - 2.0 h.0
Nauplii 59.0 10.0 26.0 26.0

 

.omswnomHm HoSOH u w mownwnomHm Momma u NH mhm>Hm Moan: n m monch u mH mnpsoz Ho>Hm u NHN

.noHpoEMOMmath AH + xv NOH hp thmGowoaopon MOM dopoohhoo who mawozH

 

 

 

70

 

 

 

 

 

Nmmm.H woow.H momw.H Hamm.a NPNO.N ado:
m NH mH w NH Gowpdpm meOOUGHo

:~\0H\0H

mmmH.m Nmmm.m :zmm.m Obbm.m mmwm.m ado:

m w wH PH NH QOHpopm

:>\ON\OH

HmmH.m How:.m hmzw.m mwbw.m wwo>.N nwmz

o NH wH NH w ooHpepm

:>\mH\0H

mmao.H mem.H :2Nm.H mmmw.H Ommm.H dez
w NH NH wH m N:0prpm wHoMHpom

i\HH\m

 

.mme can :PmH 2H szHmaoc :OPHQmHQoou cows 90% COmHHwQEoo oonlpmom m.hoMSB .N< oHQmB

71

 

 

 

 

 

 

 

 

 

 

w:om.o :0mH.H mme.H Hmwm.H m®:N.H
NH m w wH NH

NOH>.H momH.N mmON.N owwm.N woo:.N
m m NH mH NH

ome.H mNHm.H mmHo.N Hmm0.N mHmH.N
0 NH w wH NH

Hmm:.H o:m~.H No>>.H mmw~.H mwmm.H
m NH wH NH m

not:
aoprpm .mm oswsmom

:>\NH\m

ado:
ooHpopm
:>\mH\w

ado:
GOHpopm woomomoo

:e\HH\m

coo:
:oprpm whooowwHo

:>\HN\OH

 

A.o.pooov Na oHnoe

72

 

 

 

 

 

 

 

 

 

NHNH.H mNoN.N NONN.N NHHN.N OHHN.N
0 NH N NH NH
NNNN.H HAHN.H HHNN.H NNNN.H ONNN.H
o NH N NH NH
NNNN.o HNNo.o HNNN.H HNNN.H mNmN.H

NH o NH NH N
NNoN.o HNHN.o NomN.H eeNe.H NNNN.H
N NH N NH NH

ado:
ooHpeHN oHoNHpoN

m>\mH\m

awoz
aOprpm .mm Sawsmom
He\mH\OH

ado:
aOprpm .mn muoNomb

:>\NH\N

coo:
:Oprpm .mm owrxmom

HN\NH\N

 

A.©.pc00v N¢ mHQmB

73

 

 

 

 

 

 

 

 

NNNH.O NNNN.o NNHN.o NNNm.o omHN.H
N NH NH NH N
HHNN.o NNNH.H HNHN.H NHNN.H NNNN.H
o NH N NH NH
NNHN.H NHNN.H NHHo.N omNm.N HNHH.N
m N NH NH NH
NHoH.H NHNN.N NNNN.N mNoN.N NNHN.N
m NH N NH NH

cows
oOHoapN

mN\mH\m

ado:
ooHpopN

mN\wH\m

coo:
ooHHoHN

mN\wH\m

ado:
ooHpoHN
mN\NH\m

wwomomoo

wamooono

onoNHpom

 

A.U.9Goov N¢ mHQwE

7h

 

 

 

 

NNNN.o mNNH.H NNNN.H NHNN.H NNNN.H not:

a N NH NH NH ooHpopN

mN\NH\o

NNom.o Nmmo.H NNNN.H NNNN.H NNNN.H one:
o NH NH N NH eoHpoHN oooaoaoo

mN\mH\m

 

H.e.neoov NH tHoaa

75

.omnmnomHm Nazca u w mowhwsomHm Momma u NH who>Hm Momma n m mmxdpaH u wH mapsoz H0>Hm u NHN

.GOprEpommawhp AH + xv NOH hp thocoNOHopos pom covoohnoo ohm mcdoZH

 

 

 

 

 

 

 

 

 

 

 

mm:®.o mMHm.H mNHm.H wmzm.H NMHw.H com:
0 NH wH NH w GOprpm
HN\mH\0H
ogHo.H wmwm.H mem.H omNm.N omNN.N ado:
m NH w wH NH :Oprpm whooovao
HNHNH\N
msz.H NMON.H HHmN.H mme.H Nme.H can:
0 NH wH NH w :oprpm
:N\HN\OH
mwa.o wmmw.o mwmm.o HNMN.H meow.H coo:
NH wH w NH m N:OHprm. mHoNHpom
HN\HH\N
.mNmH was :NQH 2H mmeoHn sovxqumooN some pom comHmeEoo oonIpmom m.%oxde .m< oHpoB

H

76

 

 

 

 

 

 

HNNN.o HHNN.o HNNN.o NNHN.o NNHN.o
N o NH NH NH
NHNN.N HNHN.H NNNN.H NNHN.H NNNN.H
N NH N NH NH
NNNN.H NNHN.H HNNN.H NNNN.H NNNo.N
0 NH NH NH w
mooH.o NNHN.H NNNN.H NHNN.H Nmmm.H
0 NH NH NH w

 

 

ado:
ooHpopN
HN\HN\OH

ado:
:Oprpm wwomomoo

HNRHN

coo:
aoprpm wcomomoo

HN\NH\N

ado:
GOHHNHm whooomeo

:N\HN\OH

 

A.o.pooov ma oHooN

77

 

 

 

 

 

 

 

 

 

 

NNNN.o NNNN.o HNNo.H NNNo.H NNHH.H
N N NH NH NH
NNNN.o NNNe.H HNNN.H NNNN.H NNNN.H

NH N NH NH N
NmzN.o mmNo.H ommm.H mmHm.N ONHN.N
0 NH w mH NH
qumd mHmmd ommoH NHNm.H ozmmH

NH m w mH NH

ado:
ooHpooN

:N\HN\0H

ado:
ooHpopN

HN\NH\N

ado:
ooHHoHN

HN\NH\N

ado:
ooHoeHN

HN\NH\N

.mm

.mm

agwsoom

maoHomU

awzxmom

oawsmom

 

H.o.pooov N< oHpoe

78

 

 

 

 

 

 

 

 

 

NHNm.o NNNN.o NHoN.o NomN.H NNNN.H
N NH N NH NH
HNNH.o mNNN.o NHoN.o NNHN.H NNNN.H

NH NH NH N N
NNNN.o NNNo.H NNNo.H NNHN.H NNNN.H
N NH N NH NH
NNNN.o NNNN.H NNNN.H NNNN.H NNNH.H
N NH N NH NH

ado:
eoHHopN

mN\mH\N

ado:
ooHpooN

mN\NN\N

coo:
ooHpopN

mN\NH\m

ado:
ooHpoHN

mN\mH\m

whooowwHo

oHoNHpom

 

76.920“; Md. mewB

79

 

 

 

 

 

 

 

 

 

NNNo.o NNNN.o NNNN.o NNmo.H Noom.H
N NH NH N NH
NNNN.o HHNN.N NNNo.H NNNN.H HNNH.H

NH NH N N NH
NNNN.o HNHH.N NNHN.o NNHN.N NNoN.H
N NH NH NH N
NNNN.o NNNH.H NNNN.H NNNN.H HONN.H

coo:
ooHpoHN

mN\mH\m

coax
ooHpopN

mN\wN\N

coo:
ooHoopN

mN\NH\m

ado:
eoHpopN

mN\mH\m

wcomomoo

whooocwHo

 

H.o.pooov NH oHooN

8O

 

 

OHNN.o
m

 

wmmm.o
m

mmNN.H
mH

Hamm.H
NH

Nwmm.H
NH

coo:
coHeopm mwomomoo
mN\NH\N

 

3:983 Na oHpoN

Figure A1.

81

The majority of zooplanktonic types captured in the vicinity
of the Monroe Power Plant during the 1973-75 studies.

\OODNChU'I-t‘wml"

. Asplanchna sp.

. Brachionus urceolaris
. Brachionus budapestinensis
. Brachionus calyciflorus

. Brachionus caudatus

. Brachionus havanaensis
. Brachionus quadridentata
. Brachionus angularis

. Platyias patulus

. Karatella cochlearis

. Karatella quadrata

. Pblyarthra sp.

. Synchae ta sp .

. Kellicottia longispina
. Notholca acuminata

. Conochilus sp.

Trichotria sp.

. Trichocerca sp.
. Rbtaria neptunia
. Mbnostyla sp.

21.
22.
23.
2h.
25.
26.
27.

28.
29.
30.
31.
32.
33.
3h.
35.
36.
37.
38.
39.
ho.

Euchlanis sp.
Filinia longiseta
Bosmina sp.
Chydorus sphaericus
Alona sp.

Daphnia retrocurva
Daphnia galeata
mendotae
Diaphanosoma sp.
Diaptomus sp.
Leptodora kindtii
Cériodophnia sp.
Filinia brachiata
Nauplii
Chnthocamptus sp.
Hexarthra sp.
Lepadélla sp.
Ploesomo sp.
Chromogaster sp.
Cyclops bicuspidotus
Pbmpholyx sp.

82

 

Figure A1. The majority of zooplanktonic types captured in the vicinity
of the Monroe Power Plant during the 1973-75 studies.

APPENDIX B

83

mhmpgd 00.9“.“qu m Pfimm whammy,

 

 

AN.HVN.H AN.HVN.N AN.HNH.N HmN.VN.H AN.HVH.N Hopes
Ho.NVN.H AN.NVN.N AN.NVN.N AN.NVN.N AN.NVN.N nooaoaoo Hopoe
ANo.vNo.o ANH.VoH.o AHH.VHH.o ANH.VHN.o HNH.VNH.o HHHoanz
AN.mVN.N Am.qu.m Am.mvN.m Hm.mvo.: Ho.mvN.N meogaoo .b pHso<
AN.NVN.N AN.NVN.N AH.NVN.N AN.NVN.H HH.NVN.N oooaoaoo pHao<
Ho.HvoN.o ANN.VHN.o ANN.VH.H ANN.V:N.o Hm.mvN.H .mw eaNEmom
AN.NVN.N AN.NHVN.oH Ho.HHVN.HH AN.Nvo.HH Ho.NHvN.N .an owsxaom
AN.HVN.N AN.:VN.HH AN.HVH.N Hmm.vN.N AN.:VH.N oaoooooHo
HNH.VNH.o HNH.VNH.N HNH.VNH.o HNH.VNH.N *HNH.VHH.o NHoNHHoN

N NH NH N NH wane

eoHpoHN

 

.ANNmH .mcoEHm anmv MNmH nonsmpmmm OP NNmH honam>oz Scam szv Hm5©H>H@:H\mNHm stccd com: .Hm mHQwB

8h

whopadc ooomhsm mucomohmomt

 

AN.NmHvN.mHN

AN.JMNVH.mHm

HH.NNHVm.Nmm

AH.NNVN.mmH

Ho.Nva:.No:

Hence

 

AH.NOHVH.NNH AN.NNHVN.NNH Hm.NoHvH.NHN AH.NNVN.NNH AN.HNHVH.HNN oooaomoo Hopoa
AN.HVN.N HH.HVN.H AN.HVN.N AN.NVN.N AN.NVH.H HHHmooz
Am.vao.HHH AN.NNHVH.NHH HH.NNVN.ONH AH.NHVH.NOH AN.NOHVN.mmH measaoo .b HH3N<
AN.NOHVH.HNH AN.oNHvN.HNH AH.NoHVN.NoN AN.NHvo.NmH Ho.NHHvN.NHN nooaoaoo HHNNH
AN.HVN.H AN.NVN.N AN.HVN.OH Ho.NVN.H AN.NNVH.NH .Nn oxvsnom
He.NHVN.Hm AN.HHVN.NH HH.NNVH.NHH AN.NVN.HH AN.HNVN.HHH .am eHeHaeo
AN.HNVN.NN Ao.NmVH.NmH Hm.HNvN.NmH Ho.:HvN.NH Hm.NNVN.mNH ouooocoHo
AN.NVN.N AN.NVH.N Am.mvH.N AN.Nvo.N *AH.NVN.N oHomeom

N NH NH N NH wane

eoHpoHN

 

ponsopmmm ou NNmH HmnEo>oz EONN

HHoHHH\N1V msoHprm HHN no

.ANNNH .nnoeHN aoaav mNNH
:ovxcdeooN Mo mmwSoHn Hdscdw ado: .Nm oprB

85

maopasn ooNMHdm mpaomoummms

 

 

AN.NHHVH.NNH Hm.mNHVN.NHH AN.NHHVN.HNH AN.HNVN.HHH HH.HHHVH.NNH Hopoe
AN.vaN.NN AN.oNVH.oN AN.NHVN.NN Ho.Nva.NH AN.NNvo.NN ooomomoo Hopoa
AH.NNVN.NN AN.NHVH.NH AN.NHVN.HN Ho.HHvN.NH AN.oNVH.NN HHHasoz
AN.NNVN.OH AN.vam.mH HH.NNvm.Nm AN.Hvo.NN AN.NmVN.Nm wwNosaos .b pHso<
AN.oNVN.NN AN.NHvo.HH AN.HNVH.HN Ho.NvN.HN HH.NHVN.HN nooaoaoo HHzoa

AH.HVN.N HH.NVN.N AN.NVH.N Hm.Nvo.N AH.NVN.OH .an samsnom

AN.NVN.N AN.NVN.N AH.NVN.oH AN.HVN.N AN.NVN.NH .an owzxaom

AN.NVN.HH AN.HHVN.HH AN.NHvo.NN AN.NNVN.NN AN.NHVN.NN onoooooHo

HH.HNVH.ON HH.HNve.NH AN.HNVN.NN Hm.mHve.mH *AH.NNVN.NN enoHHaom
I. ours

 

.ANNmH .mnoEHm Sonmv
MNmH Nongopmom op NNmH noQEo>oz EOHN ApopHH\mthEdcv mcoprpm HHw pm NNHmcoc Hudson ado: .mm oprB

86

 

 

 

m.OMH N.me m.NNH N.o:H m.NN m.MNH m.MNN m.m:N Hmpoe
H.NN N.NN N.NH N.NN N.NN N.NN N.NNH o.ooH nooaoaoo Hopoa
N.NN H.HN N.N N.HN N.HH N.NN N.NHH N.NN HHHmsez
m.N: N.N: N.mm N.Hm o.NN N.om N.Nm N.NN mm~d§&ma .b pHSU<
N.NH N.NH N.NH H.NN H.NN N.NH N.NN N.NN oooaoaoo pHao<
H.N N.N H.N N.N N.N N.N H.N N.NH .Nn oswsnom
N.N N.N N.NH N.NH N.N N.N N.N N.NH .mm awaxmdm
N.NH N.NH N.:H N.N m.N 0.0H m.mN N.N: NHmoocwHo
N.N: o.NN H.NN o.mm m.mm N.N: N.ON N.OOH meMHpom
Ncho>m coocumpm< Ncho>m sooshopm< mcho>m coocnoHNN wcho>m coonuopm< wxoe
N NH 0 NH
.ANNNH .nnoeHN sonmv NNNH nonsopaom op NNNH
Honao>oz Scam UOHHom oEHp New coprpm nowo pm mxwp N0nwfi onu How HHopHH\mHopE::V NpHmcoc :80: .:m oHnNB

HICHIGQ

77

U

777777777777777

129300