zooplankton of the big eau pleine reservoir alan buchanan

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Zooplankton of the Big Eau Pleine Reservoir by Alan Buchanan Wisconsin Cooperative Fishery Research Unit A THESIS submitted in partial fulfillment of the requirements for the degree MASTER OF SCIENCE College of Natural Resources UNIVERSITY OF WISCONSIN Stevens Point, Wisconsin August 1976

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Zooplankton of the Big Eau Pleine Reservoir

by

Alan Buchanan

Wisconsin Cooperative Fishery Research Unit

A THESIS

submitted in partial fulfillment of the

requirements for the degree

MASTER OF SCIENCE

College of Natural Resources

UNIVERSITY OF WISCONSIN

Stevens Point, Wisconsin

August 1976

ABSTRACT

Composition, abundance, and distribution of zoo­

plankton were determined during September, 1973 to September,

1974 in the Big Eau Pleine Reservoir, a eutrophic, 2832 ha

(10.93 mi 2 ) fluctuating reservoir in central Wisconsin.

Yearly water level fluctuations of up to 9.6m (31.5 ft.)

occur commonly, and maximum drawdown occurs during winter.

The yearly drawdown appeared to have little affect on the

zooplankton populations because: a) zooplankton species

composition in the Big Eau Pleine Reservoir was typical

for lakes of the Great Lakes Region, b) the mean annual

total number of 298 zooplan}:ton per liter and biomass of

362 mg/m3 (13.8 kg/ha) for the ice-free period of September

20 through December 1, 1973 3nd May 13 through September 5,

1974, were high in compariso~ wi~h other bodies of water,

c) the 30-year mean annual flushing rate of 158 days is

considerably greater than that thought to be limiting to

zooplankton, and d) a winter drawdown, as in the Big Eau

Pleine Reservoir, occurs when zooplankton numbers are low

and has less affect than if it occurred during summer,

when zooplankton numbers are high.

The reservoir remained thermally unstratified except

for a brief period during late June and early July. Low

water transparency could probably be attributed to algae

blooms and suspended sediments during summer and suspended

sediments during winter. Dissolved oxygen was minimal

in winter, reaching concentrations as low as 0.1 ppm in

January and February. Of 25 zooplankton taxa in the

reservoir, at least 17 were found at each of 6 sampling

sites. Copepod nauplii, Rotifera, and Chydorus sphaericus

comprised 66 to 75% of zooplankton numbers. As is typical

in other bodies of water, maximum biomass and number per

liter occurred during summer and minima during winter.

The reservoir, probably due to a lack of horizontal and

vertical thermal stratification, had little horizontal or

vertical differences in zooplankton number per liter, and

no significant horizontal differences in zooplankton

biomass.

i

ACKNOWLEDGEMENTS

I express sincere thanks lo the following for support

given during this project. The Wisconsin Cooperative Fishery

Research Unit provided facilities and equipment and the

Wisconsin Valley Improvement Company funded the study and

provided background data. Dr. Gerald Jacobi, my advisor,

supplied advice and direction during the study, and edited

the manuscript. Dr.'s Daniel Coble, Henry Booke, and Ted

Roeder, members of my graduate committee, provided advice

during the study and edited the manuscript. James Selgeby,

Biologist, Ashland Biological Station, provided advice

while the study was being planned, confirmed my zooplank-

ton identifications, and edited the manuscript. Dr. Fred

Hilpert, Associate Director of Instructional Data Proces­

sing at the University of Wisconsin-Stevens Point, provided

advice and assistance with the statistics employed in data

analysis. Students of the Wisconsin Cooperative Fishery

Research Unit, expecially Tom Joy and Jerry Kaster, supplied

advice and moral support. Lynette Densch, my significant

other, supplied pertinent suggestions and stuck with me

through it all.

.J..-1.

TABLE OF CONTENTS

Acknowledgements••••·••••••·•••••••••••·•••••••••••••• i

List of Tables • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •

List of Figures • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •

List of Appendices••••••••··•·•·••••··••·•••••••••••••

INTRODUCTION • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •

MATERIALS AND METHODS • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •

V

vi

viii

1

5

RESULTS • ••••••••• --.- •- • • •-•............... • • • • • • • • • • • • • • • • 9

Water temperature•••••••••••••••·•·••·•••••••••••• 9

Dissolved oxygen•••••••••••••••••·••••·••••••••••• 9

Water transparency•··•••••••·••••••••·•••••••••••• 12

Species composition•••••·••••••·••••··•••••••••·•• 12

Zooplankton numbers•·••••••••••••••••••••••••••••• 15

Percent composition··•••·•••••••·••••••••••••••••• 18

Daphnia .:2..l?.E.• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 19

Ceriodaphnia reticulata •••··•••••••••••••••••••••• 19

Diapryanosoma leuchtenbergianum ···•••••••••••••·••• 19

Bosmina longirostris •••••••••••••••••••••••••••••• 19

Chydorus sphaericus ••••••••••••••••••••••••••••••• 21

Rotifera • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 21

Calanoid copepods •·••••••••••••••••••••••••••••••• 24

Cyclopoid copepods •·••••••••••••·•••·••·•••••••••• 24

Copepod nauplii •••••••••••••••••••••·••••••••••••• 25

Minor taxa • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •

Vertical differences • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •

Horizontal differences ••••••••••••••••••••••••••••

25

25

28

iii

Biomass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of the #10 Van Dorn and the #10 oblique Clarke Bumpus.

. . . . . . . .

Comparison of #10 Van Dorn and Van Dorn total • • • • •

Relationships between physical and chemical characteristics and zooplankton numbers.

. . . . . . .

Correlations among numbers of taxa • • • • • • • • • • • • • • • •

DISCUSSION • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •

Physical and chemical characteristics • • • • • • • • • • • • •

Species composition • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •

Total numbers • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •

Annual fluctuafions in zooplankton number • • • • • • • • •

Species percent composition • • • • • • • • • • • • • • • • • • • • • • •

Daphnia .2.E.E.• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •

28

30

31

32

35

37

37

38

38

39

39

42

Ceriodaphnia reticulata ··•••••·•·••••••••••••••••• 43

Diaphanosoma leuchtenbergianum ••••••••••••••·•••·• 43

Bosmina longirostris •·••·••••••••••••••••••••••••• 44

Chydorus sphaericus • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •

Rotifera ···························~·············· Calanoid copepods

Cyclopoid copepods

• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •

• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •

44

45

45

46

Copepod nauplii ••••••••••··••••••••••••••••••••••• 46

Minor taxa • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 47

Vertical differences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

Horizontal differences • • • • • • • • • • • • • • • • • • • • • • • • • • • • 49

Biomass • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 49

Comparison of samplers••••••••••••••··•••••••••••• 51

Relationships between physical and chemical characteristics and zooplankton numbers

. . . . . . . 52

iv

CONCLUSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . LIST OF REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . APPENDICES • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •

57

59

63

V

LIST OF TABLES

Table Page

1. Species composition of zooplankton in the •••••• 14 Big Eau Pleine Reservoir.

2. The percent more organisms retained by the••••• 33 #200 soil screen (Van Dorn total) than by the #100 soil screen {#10 Van Dorn), based on yearly averages, all depths averaged.

3. Mean monthly and mean annual number per liter •• 40 of zooplankton in the Big Eau Pleine Reservoir and other bodies of water.

4. Biomass {mg/m3) in the Big Eau Pleine Reser-••• 50 voir and other bodies of water.

Figure

1.

2.

vi

LIST OF FIGURES

Big Eau Pleine Reservoir, Marathon County, Wisconsin.

• • • • •

Depth of water at Moon Bridge in the Big Eau Pleine Reservoir during September, 1973 to September, 1974 (from Wisconsin Valley Im­provement Co. hydrograph).

• • •

Page

2

3

3. Water temperature in °c in the Big Eau Pleine •• 10 Reservoir at 1m and at the deepest depth sampled.

4. Dissolved oxygen in the Big Eau Pleine Reser- •• 11 voir at 1m and at the deepest depth sampled.

s. Secchi disk readings in the Big Eau Pleine ••••• 13 Reservoir during September, 1973 to Septem-ber, 1974.

6a. Total zooplankton numbers in the Big Eau••••••• 16 Pleine Reservoir at Sites I, II, and III,

6b.

during September, 1973 to September, 1974.

Total zooplankton numbers at Sites IV and V in the Big Eau Pleine Reservoir, and at Site VI below the dam, during September, 1973 to September, 1974.

• • • • 17

7. Numbers (Van Dorn total, all depths averaged) •• 20 of Daphnia fil2.E.•, Ceriodaphnia reticulata, and Diaphanosoma leuchtenbergianum in the Big Eau Pleine Reservoir, and at Site VI below the dam, during September, 1973 to September, 1974.

Sa. Numbers (Van Dorn total, all depths averaged) •• 22 of Bosmina longirostris, Chydorus sphaericus, and Rotifera at Sites I, II, and III of the Big Eau Pleine Reservoir during September, 1973 to September, 1974.

8b. Numbers (Van Dorn total, all depths averaged) •• 23 of Bosmina longirostris, Chvdorus sohaericus, and Rotifera at Sites IV and V of the Big Eau Pleine Reservoir, and at Site VI below the dam, during September, 1973 to September, 1974.

vii

Figure Page

9a. Numbers (Van Dorn total, all depths averaged) •• 26 of Calanoid copepods, Copepod n~uplii, and Cyclopoid copepods at Sites I, II, and III of the Big Eau Pleine Reservoir during September, 1973 to September, 1974.

9b. Numbers (Van Dorn total, all depths averaged) •• 27 of Calanoid copepods, Copepod nauplii, and Cyclopoid copepods at Sites IV and V of the Big Eau Pleine Reservoir, and at Site VI below the dam, during September, 1973 to September, 1974.

10. Biomass in mg/m3 (log scale), based on #10 ••••• 29 oblique Clarke Bumpus samples, at Sites I through Vin the Big Eau Pleine Reservoir, and at Site VI below the dam, during September, 1?73 to September, 1974.

Appendix

A.

viii

LIST OF APPENDICES

Temperature in °cat Sites I through Vin the Big Eau Pleine Reservoir, and at Site VI below the dam, during September, 1973 to September, 1974.

• • • •

Page

63

B. Dissolved oxygen in ppm, and percent satur- •• 65 ation at Sites I through Vin the Big Eau Pleine Reservoir, and at Site VI below the dam, during August 31, 1973 through Septem-ber 5, 1974.

c. Secchi disk readings in meters at Sites I•••• 68 through Vin the Big Eau Pleine Reservoir,

D.

and at Site VI below the dam, during August 31, 1973 through September 5, 1974.

Monthly mean number per liter (#10 oblique Clarke Bumpus) of zooplankton at Sites I through Vin the Big Eau Ple~ne Reservoir, and at Site VI below the dam, during September, 1973 to September, 1974.

• • • 69

E. Monthly mean number per liter (#10 Van••••••• 75 Dorn) of zooplankton at Sites I through Vin the Big Eau Pleine Reservoir, and at Site VI below the dam, during September, 1973 to September, 1974.

F. Monthly mean number per liter (Van Dorn•••••• 88 total) of zooplankton at Sites I through Vin the Big Eau Pleine Reservoir, and at Site VI below the dam, during September, 1973 to September, 1974.

G. The percent composition of the 9 major taxa •• 101 of zooplankton at Sites I through Vin the Big Eau Pleine Reservoir, and at Site VI below the dam, during September, 1973 to September, 1974.

H. Significance of correlations between physi- •• 102 cal and chemical characteristics and zoo-plankton numbers at Sites I through Vin the Big Eau Pleine Reservoir, and at Site VI below the dam.

INTRODUCTION

Objectives of this study were to measure the composition, abundance,

and distribution of zooplankton in the Big Eau Pleine Reservoir, and to

determine if yearly water level fluctuations influence the zooplankton

populations.

The Big Eau Pleine Reservoir, Lat. 44° 44 1 , Long. 89° 46' (Martin

and Hanson, 1966), is a eutrophic, flow-augmentation reservoir located

in Marathon County. The dam impounding the reservoir is located approxi­

mately 8.1 km (5 mi) southwest of Mosinee, Wisconsin. The reservoir

has a maximum depth of 14m (46 ft.) at full pool, and a surface area of

2832 ha (10.93 mi 2 ). It extends 31.4 km {19.5 mi) east from Bradley

Bridge to the Big Eau Pleine Dam (Fig. 1). The Big Eau Pleine River,

the main tributary, has a mean annual flow (49 year mean) (USGS, 1975)

at Stratford Bridge of 4.84 m3 per second (171 cfs). Fenwood Creek and

Freeman Creek, the other major tributaries, have mean annual flows

(mean of 6 dates between October, 1974 and September, 1975) of 1.03 m3

per second (37 cfs) and 0.61 m3 per second (22 cfs), respectively.

Yearly water level fluctuations of up to 9.6m (31.5 ft.) occur comnonly,

and full stage normally occurs from mid-April to early May, after the

spring snow melt, followed by a steady decline in water level from mid­

June to late September, after which water level is relatively stable

until early December. A rapid decline in water level in December leads

to the yearly low in late February or early March (Fig. 2).

Average chemical characteristics (based on thrice monthly samples

taken during April, 1974 through September 3, 1975) of the Big Eau Pleine

Reservoir surface waters near the dam were: orthophosphate, 0.052 ppm;

Halder Bridge

Big Ea" Pleine Co"nty Park

, Moon Bridge

1 km

Figure 1: Big Eau Pleine Re·servoir, Marathon County, Wisconsin.

Big

I\.

VI

14

13

12

11 - .. 10

... 9 ._ cu -cu 8 :::e a:: 1

....i:: - 6 CL CD

Q s 4

3

2

1

s

--. ---.-.--

0 N 1973

·· ..

D

··­... .. .

..

J

---· . ·-.·

F

--­. .

M

.----- --···-·-. ·-...• _______ _ ··-----

A M J J A s 1974

Figure 2. Depth of water at Moon Bridge in the Big Eau Pleine Reservoir during September, 1973 to September, 1974(from Wisconsin Valley Improvement Co. hydrograph).

nitrate plus nitrite nitrogen, 0.189 ppm; total alkalinity, 32 ppm;

5-day BOD, 3.0 ppm; and ca lei um hardness, 30 ppm (Shaw, 1976, unpub­

lished). The Big Eau Pleine Reservoir exhibited phytoplankton blooms

of up to 11,810 cells/ml during the surrrner of 1975 (Shaw, 1976, unpub­

lished). At times during the summer dissolved oxygen reached super­

saturation, whereas during the winter, low dissolved oxygen was coITTTion,

and several winter fish-kills have been observed (Wisconsin DNR, per­

sonal colTITlunication).

..;

Jv'.ATEP.IALS AND METBODS

Zooplankton samples were collected twice monthly from

September, 1973 to September, 1974 at five sites distributed

over the length of the reservoir, and at one site below the

Big Eau Pleine Dam. Sites I through V were 20.9, 12.6, 9.9,

6.1, and 1.1 km, respectively, above the Big Eau Pleine Dam.

Site VI was 0.3 km below the dam (Fig. 1). All sites were

located in the old river channel.

At each site a 12.5 cm diameter Clarke Bumpus sampler

with a number 10 mesh (0.158 mm opening) net was towed

obliquely from bottom to surface. The volume of water that

passed through the sampler for each revolution registered

on the counter was determinec by towing the open sampler,

without a net, for 100m at a speed of 4.5 km/hr, the speed

used in sampling. A 25° angle of the towing cable from

the vertical was maintained to keep the towing speed

constant for all tows. The amount of water contained in a

cylinder 12.5 cm X 100m was divided by the number of revo­

lutions registered on the counter.

At each site, duplicate samples combined for each depth

were taken with a 2-liter Van Dorn horizontal water bottle

at 1m, 2.Sm, Sm, and 10m, where depth allowed. These

samples were poured through number 100 (mesh opening=

0.149mm) and number 200 {mesh opening= 0.074mm) soil

screens. The organisms retained by each screen were pre­

served and stored. All samples were preserved in 4%

formalin and stained with R0se Bengal's solution. Cnly

Van Dorn samples were taken during months of ice cover.

Additional Van Dorn sarnples were collected at the

same depths, that plankton samples were taken, for deter­

mination of dissolved oxygen and te~perature. Water samples

for oxygen determination were drained from the sampler

through a tube to the bottom of a 300 ml BOD bottle that

was allowed to overflow for 30 seconds. I used the Azide

modification of the Winkler method (APHA, 1971) to fix and

titrate the oxygen samples. I inserted a hand mercury

thermometer into the drain of the Van Dorn and allowed

water to run over it for one minute to determine tempera­

ture. Water transparency was measured at each site with

a 20 cm diameter Secchi disk.

Clarke Bumpus samples were dil~ted to a known volume

and 1 ml subsamples were taken with a Hensen-Stemple

pipette. Two subsample counts were made for each sample.

If the two counts differed by more than 10% of the smaller

count, a third subsample was counted. The two closest

counts were then recorded if they differed by 10% or less

of the smaller. When all three counts varied widely the

entire sample was re-combined, re-diluted, and subsarnpled

again. Organisms in the Van Dorn samples were counted in

total.

Cladocera were identified and counted to genus, Copepoda

to suborder, and Rotifera to class in a circular counting

wheel (Ward, 1955) at 60 magnifications. Species of

Crustacea in Clarke Bumpus samples in the summer and in Van

Dorn samples in winter w~re keyed out to determine species

composition at each site. Keys used were in Brooks (1957,

1959), Wilson (1959) and Yeatman (1959). Identifications

were confirmed by James Selgeby, Biologist, U.S. Fish &

Wildlife Service, Ashland, Wisconsin, Biological Station.

Duplicate quarters of the Clarke Bumpus oblique

samples were dried at 60°c for 24 hours and weighed to

0 obtain dry weight, ignited at 550 C for 10 hours and re-

weighed to obtain ash-free dry weight. Each sample was

divided into eighths with a folsom plankton splitter.

Randomly chosen subsamples were paired to form duplicate

quarters. Quarters with substantial amounts of phyto­

plankton were sieved through three soil screens of increas­

ingly finer mesh size (0.250 mm, 0.158 mm, and 0.074 mm)

to remove the phytoplankton. Larger organisms, which

make up the bulk of the zooplankton biom2ss, were retained

by a #60 (mesh opening= 0.250 mm) soil screen and were

used for biomass determination. Smaller organisms, such

as copepod nauplii and rotifers, along with approximately

95% of the phytoplankton, passed through the #60 screen and

w~re not used for biomass determinations. Phytoplankton

retained by the #60 soil screen (approximately 5%) and

included in the biomass determinations perhaps compensated

for the loss of the smaller organisms that passed through

the #60 soil screen.

The relationships between physical and chemical char­

acteristics and zooplankton numbers, and the relationships

among species of zooplankton were determined by regression

c1nalysis. A series of J ,_nr ur r('.grc!ssions \•Jere calculated

between 19 variables: depth of water at the dam, Secchi

disk readings, depth of sample, water temperature, dissolved

oxygen, and numbers of Daphn5.a ~-, Cerjodaphnia reticulata,

Dianhanosoma leuchtenbergi2num, Bosmina longirostris,

Macrothrix laticornis, Levdioia quadrangularis, Chydo~~

sphaericus, Lentodora kindtii, calanoid copepods, copepod

nauplii, cyclopoid copepods, Rotifera, Daphnia ephipia, and

Ostracoda.

RESULTS

Water temperature

Surface water temperatures were similar at all sites

0 0 (Fig. 3). Peak temperatures of 25.0 C to 26.5 C occurred

on August 19, 1974 at Sites I and II, and on July 16, 1974

at Sites III through VI, whereas minimum temperatures of

o0 c to 1°c occurred between November 11, 1973 and February

22, 1974 at all sites. The reservoir remained unstrati­

fied at all sites throughout most of the year. Tempera­

ture stratification occurred at Sites I through IV only on

June 26 and 27, 1974, and at Site Von June 27 to July 16,

1974, and did not occur at Si:e VI at any time during the

year.

Dissolved OXygen

Seasonal trends in dissolved oxygen concentration

were similar at all sites (Fig. 4). Peak oxygen concen­

trations of 12.0 ppm (90% saturation) and 15.2 ppm (168%

saturation) occurred on September 7, 1973 at Sites I and

VI, respectively. Peak oxygen concentrations of 12.8 ppm

(147% saturation) to 18.1 ppm (215% saturation) occurred

at Sites II through Von June 26 and 27, 1974. Dissolved

oxygen concentrations at the surface during daytime were

above 5 ppm throughout most of the year. Dissolved oxygen

concentrations reached minima of 2.0 ppm (14% saturation),

0.1 ppm (0.7% saturation), and 1.8 ppm (13% saturation) at

30 20 \ ".----·, 10 "

30

·-•....._

Site I

Site II

Site Ill

Site IY

Site Y

Site YI

s 0 N D J f M A M 1973 1974

J J A s

Figure 3: Water temperature in °c in the Big Eau Pleine Reservoir at lm (-.-) and at the deepest depth sampled (----) (2.5m at Site I, Sm at Sites II, III, IV, and VI, and 10m at Site V).

.1 .1

18 Site I

12 ·, • ..-·----. ~-6 ~ "-•- -• 'h~,(~--::-;:::~. ~I ___ ,

. E . Q, . a.

= = • ica >-

. 18 Sire II

12

6 ./·-·

18 Site Ill

12

6 / ........... .

~ 18 Site IV

-: 12 • /~ ► ..-·-----,~·----- /•--,,._~----· ' . 0 ·,,·,,,•--•-------- ' - ... ____ ................ ",.,,.,,,,,, = 6 "· ........ ___ ... - .......... __ •

Q • \--•

18

s 0 N D J F

1973

Site Y

Site VI

M A I 1974

J J A s

Figure 4: Dissolved O>:ygen in the Big Eau Pleine Reservoir in 1973 and 1974 at lm (--_) and at the deepest depth iampled {----) (2.5m at Site 1. 5m at Sites 11; III, IV, and VI, and 10m at Site V).

Sites I, II, and III, re~p0ctiv 0 ly, ~n ,, td-January, 1974;

0.8 ppm (6.3% saturation), and 2.0 ppm (13% saturation) at

Sites IV and VI, r~spectively, in mid-February; and 0.3 ppm

(2.1% saturation) at Site Vin early March, 1974.

Stratification of dissolved oxygen was similar at all

sites. In general, the reservoir remained unstratified

from mid-to-late September, 1973 until late May to mid-June,

1974. Oxygen stratification began in mid-June at Site I,

in late May at Sites II through v, and in mid-July at

Site VI.

Water transparency

Water transparency was similar at all sites and was

low throughout the year except for a brief period between

mid-May and early June, 1974 when readings reached 1.2m,

1.9m, 2.0m, 2.1m, 1.9m, and 2.2m at Sites I through VI,

respectively. Low transparency could have been due to

algae and wind-suspended sediments during the summer months,

and to suspended sediments in the winter.

Species composition

Zooplankton found in the Big Eau Pleine Reservoir were:

Daphnia pulex Leydig, 1860 emend. Richard, 1896; Q. galeata

Sars, 1864 mendotae Birge, 1918; Q. parvula Fordyce, 1901;

Q• retrocurva Forbes, 1882; D. ambigua Scourfield, 1947;

Ceriodaphnia reticulata (Jurine), 1820; .Q.i_aphanosoma

leuchtenbergianum Fischer, 1850; Leptodora kindtii (Focke),

... "-• -•

== C

..r: -Q.

• Q

3

2

13

Site I

1 ...-·------------.-•--.-·---- -----~-✓-, ~-------· _.,,,,,.,,- ·--·--. -. 3 Site II 2· • 1 - /\

. ___ .--.----·--------•--.-·------------ --·------. 3

2

1

3

2

1

3

2

1

3

2

1

- -·-• ·-•-•

Site Ill

. ' / . -· '\. ---, ----- •-·--•-----.--•-•------:--· ~ .... _. __ _..., ·-·-· Site IV

Site Y

/""'·-----•--•-•---.--------·-• ............ ----------- ·---.-•...... . . ........ _ __,,,,,-

Site VI

-·---·-·-·-·-----·-·-----.-/\ _____________ _ S I O I N I D I

1973 J I F I I I A I M I J I J I A I s 1

1974

figure 5. Secchi disk readings in the Big Eau Pleine Reservoir during September, 1973 to September, 1974.

14

Table 1: Species composition of zooplankton in the Big Eau Pleine Reservoir.

,_ __ ._ ·-·--· ---· -- --

Site Site Site Site Site Site I II III IV V VI

Cladocera

Daphnia 2ule~ + + + + + + Daohnia galeatae mendotae + + + + + + Daphnia parvula + + + + Daphnia retrocurva + + + Daohnia ambigua + Ceriodaphnia reticulate + + + + + + Diaphanosoma leuchtenbergianua + + + + + + Leptodora kindtii + + + + + + Bosmina longirostri1 + + + + + + Leydigia guadrangularit +- + + + + + Alona .fil?.• + + + + + + Chy:dorus sphaericu1 + + + + + + Macrothrix laticorni1 + + Camptocercu~ rectirostri1 + Pleuroxus denticulatus +

Copepoda

Diaptomus siciloide1 + + + + + + Diaptomus pallidu1 + + + + + + Qyclops bicusoidatua tho:rnasi + + + + + + Cyclops vernalia + + + + + + MesOCIClOJ2S ~ + + + + + + Eucyclops speratu1 + Eucyclops agilil + + + M3crocyclops albida1 +

Harpactiooida +

Roti!era + + + + + +

Ostracoda + + + + +

Total taxa 25 19 17 17.· 18 17

+ = present.

1844; Bosmina lonoirostris (O. F. Viull,:-~r), 1785; Leydiaia

guadrangularis (Leydig), 1860; Alona Baird, 1850 sp.;

Chydorus sphaericus (O. F. Muller), 1785; Macrothrix

laticornis (Jurine), 1820; Camptocerc~ rectirostris

Schedler, 1862; Pleuroxus denticulatus Birge, 1878;

Diaptomus siciloides Lilljeborg, 1889; £• pallidus Herrick,

1879; Cyclops bicuspicatus thomasi s. A. Forbes, 1882;

c. vernalis Fischer, 1853; Mesocyclops edax (S. A. Forbes),

1891; Eucyclops speratus (Lilljeborg), 1901; f• agilis

(Koch), 1838; Macrocyclops albidus (Jurine), 1820;

Harpacticoid copepods; Rotifera; and Ostracoda (Table 1).

Number of taxa at each site ranged from 25 at Site I

to 17 at Sites III, IV, and VI. T~e taxa found at one

site but not another may have been present but missed in

sampling at sites at which they were not found.

Camptocercus rectirostris, Pleuroxus denticulatus, Daphnia

ambigua, Eucvclops speratus, and Harpacticoid copepods,

found only at Site I, and Macrothrix laticornis, found

only at Sites I and II, were in low numbers, and with the

exception of~- laticornis, were each found in 5 or less

samples. Fifteen of the 25 taxa were found at all sites.

Eucyclops agilis, found only at Sites I, III, and IV, and

Macrocyclops albidus, found only at Site IV, were also

found in few samples.

Zooplankton abundance

Seasonal trends in total abundance of zooplankton were

similar at all sites for the three kinds of samples:

... •

1500

1000

500

100 10

_: 1000 ... • Q, ... u

...Q 500 e :,

:z:

100 10

1000

500

100 10

•. ·· ..

lb

Site I

Site II

. .. ·. · ..

.. ..

. . . . : ~

.

=~:··-.:. . .-·"' ·. .•· ... •····· . -~-.. ··... , .. ,•· -=~ .... /·==------

.• . .. ·.

s

.. •···•·. . ~ -.><: ' • • . ••• , ,' .::~,.,,' ·--• ... ___ ··.. .· , .. ' ... - '""::~I .: ! I'"•• I J. • .. ,.-:,,

0 N 1973

D J

Site Ill

f M A M J J 1974

A s

figure 6a. Total zooplankton numbers in the Big Eau Pleine Reservoir at Sites I, II, and III, during September, 1973 to September, 1974. #10 oblique Clarke Bumpus(--), #10 Van Dorn, all depths averaged(----), and Van Dorn total (····). Note different scales for Oto 10, 10 to 100, and over 100.

... • -

100

500

100 10

12S0

- 1000 ... • Q. ... • e S00 =­:z

10 10

1000

500

100 10

s 0 N 1973

D

17

Site IV

Site Y

Site VI

J f I

. . . ..

. . . . . . .

: · .

A M J 1974

.·•

J A s

figure 6b. Total zooplankton numbers at Sttes IV and V tn the Btg Eau Pleine Reservoir, and at Site VI below the dam, during September, 1973 to September, 1974. #10 oblique Clarke Bumpus(--), #10 Van Dorn, all depths averaged(----), and Van Dorn total, all depths averaged(····}. Note different scales for Oto 10, 10 to 100, and over 100.

18

1) Van Dorn total (in~lurl0s all organisms r~tained by a

#100 plus a #200 soil scr~en) for all cepths averaged, 2)

#10 Van Dorn (includes all organisms retained by a #100

soil screen) for all depths averaged, and 3) #10 oblique

Clarke Bumpus (Fig. 6; Appendices D, E, and F). Number

per liter based on Van Dorn total decreased from between

306 and 1000 in September, 1973 to between 0.25 and 71.8

on January 25 to March 25. Numbers increased in late

April to a mid-to-late May peak of 460 to 1150 organisms

per liter, after which there was a substantial decrease,

followed by a second summer peak in mid-August to early

September of 459 to 1518 organisms per liter.

Percent composition

Copepod nauplii, Rotifera, and Chydorus sphaericus

comprised 66 to 75% of zooplankton numbers at Sites I

through v, whereas copepod nauplii, Rotifera, and cyclo­

poid copepods comprised 73% of zooplankton numbers at

Site VI, based on Van Dorn total yearly averages, from

September, 1973 to September, 1974. Nine taxa comprised

99.4 to 99.9% of zooplankton numbers at each site. These

taxa and their percentage of the total were: copepod

nauplii, 22.0 to 34.6%; Rotifera, 19.4 to 31.6%;

£• sphaericus, 9.0 to 19.7%; cyclopoid copepods, 7.3 to

13.4%; Bosmin~ longirostri~, 4.0 to 11.5%; Daphnia E.EE_·,

3.9 to 9.7%; calanoid copepods, 0.7 to 3.8%; Diaphanosoma

leuchtenbergianum, 1.4 to 3.5%; and Ceriodaphnia

reticulata, 0.02 to 1.0%.

J,:::,

Daphnia ~-

The seasonal trend of .!2~:: .. X~l~ni~ ~-, which ranged from

0 to 128/1, was similar at all sites (Fig. 7). All sites

exhibited at least two summer peaks, the first between

May 28 and June 13, of 37 to 128 Daphnia/1, and the last

between July 16 and September 5, of 37 to 101 Daphnia/1.

Few Daphnia ~- were found in winter, and numbers reached

zero per liter at all sites between January 18 and March 25,

1974.

Ceriodaphnia retictilata

Density of Ceriodaohnia reticulata ranged from Oto

34/1, and peak numbers occurred in late summer or fall at

all sites (Fig. 7). c. reticulata were not found in samples

between mid-November, 1973 and late April to mid-July, 1974.

Diaphanosoma leuchtenbergianum

The seasonal trend of Diaphanosoma leuchtenberaianum,

which ranged from Oto 67/1, was similar at all sites

(Fig. 7). D. leuchtenberaianurn exhibited a single peak in

late August or September at all sites except Site I where

an additional peak occurred in mid-July. Density of

D. leuchtenbergianum was low to nil between mid-November,

1973 and late June to mid-July, 1974.

Bosmina longirostris

Bosmina longirostris ranged from Oto 229/1, and one

to three summer maxima were seen at all sites (Fig. 8).

... • -... • ~ ... cu

..Q

e =-:;z:

'- V

140 Site I

100

60

20 ._._, ......... ........ J

140 Site II

100

60 =,,_. 20 .--•.:. ~

'll'r . ..,.,__ -•---

140 Site Ill

100

60 ',._ ..... . --· 20 . - _·:~·:,~•-•

140 Site IV

100 . 60

. -~ 20 ·=~---•--=~---------

/\/-......_,,-;.:>:::~• :..::..::....:c..::..;:.;..,....__;_-==c=.a-------_....,~~--:. -· - - - .·

140 Site Y

100

60 :.:..:··. . 1·-......... ·, /. 2 0 • -:: :-:-:-•-..._ '-.. /. I • • •

J--L:=.:..!-•:..;:--=.-•.;.1: ~L ........:• =•~=====L.:L;.f,-=--,.__ __ ...:: __ :::::::.._• ___ •....;-:::::• •.:..'.• •..:...••_• •_• --

140

100

60

s 0 N 1973

D J

Site YI

f M A M J J A S 1974

figure 7. Numbers (Van Dorn total, all depths averaged) of Daphnia spp. (--)~ Cerioda hnia reticulata (--~-}, and Diaphanosoma l@uchtenbetgianum ...• ) in the Big Eau Pleine Reservoir~ and at Site Vf below the dam, during September, 1973 to September, 1974. -

,. J.

.in late May, late Juno, and mLd-Augu,~t, at Sites 111 iind

VI in mid-to-late May 2nd early September, and at Sites IV

and Vin mid-August to early September. A late fall peak

occurred in October or November, 1973 at all sites except

Site IV. Few B. longirostris were found during winter and

B. longirostris reached 0/1 at all sites between February 1

and April 21.

Chydorus sphaericus

Seasonal trends of Chydorus sphaericus, which ranged

from Oto 567/1, were similar at all sites (Fig. 8). One

or two peaks of C. sphaericus were seen .in the summer and

fall at each site. C. sptaericus exhibited a late June

pulse at Sites II through VI, and a larger late August to

late September peak at all sites. Less than 5 c. sphaericus

per liter were found between mid-February and late May, and

£• sphaericus reached 0/1 at all sites between mid-January

and late April.

Rotifera

Density of Rotifera ranged from Oto 731/1 and showed

two to three summer peaks at all sites (Fig. 8). Peaks of

74 to 731/1 in mid-to-late May and of 117 to 308/1 in late

June to mid-July occurred at all sites. A third peak of

Rotifera occurred in late August or early September at

Sites I, V, and VI. Rotifers also exhibited peaks in

abundance in October, 1973 at Site VI, on December 1, 1973

70

600

500

400

300

200

100

10

700 ... 600 • -- 500 ... ~ 400 ... • ..Q

e :::::t

:z:

300

200

100

10

700

600

500

400

300

200

100

.

/\ . ·---. .,.rl,a.._,._ :.••· ·,.!.._. __ . --~-~

. .. ·-:

. ~ . . . ·-. ,,,,,,. --·~-~- ~ .. --• . -:.•.~::.~:~.-.:~-- -

. .

S O N D J 1973

22

Site I

Site II

Site Ill

M

• .

A M J J A S 1974

Figure Sa. Numbers (Van Dorn total, all depths avera9ed) of Bosmina longirostris (---~), Chydorus sphaericus (····), and Rotifera (~) at Sites I, II, and III of the Big Eau Pleine Reservoir during Septemoer, 1973 to September, 1974. Note the different scales for Oto 10, 10 to 100, and over 100.

700 Site IV 600

500

400

300

200

100

10

700 Site V ,_ 600 cu - 500 -,_ ., 400 Q,

. . ,_

300 cu -4

E 200 ::t :z::

100

10 ;<".~~\-c:,_,= ----·-.. ,•,. /\-/1\~f ··········--::-.- - - -- ............... __ --· ·- ······:•~·-·····•·

700 Site VI 600

500

400

300

200

100

10

1973 1974

Figure Sb. Numbers (V.an Dorn total, all depths avera9ed} of·Bosmina longi rostri s ·(-~~-}, Chydorus sphaericus t · .. ·), and Rotffera ( __ )·at Sites IV and V of the Big Eau Pleine Reservoir, and at Sfte VI below the dam, during September, 1973 to September, 1974. Note the different scales for Oto 10, 10 to 100, and over 100.

Rt Site II, in late J~nuary, 1974 at Sit~s III and IV, and

in mid-February, 1974 at Site V. Rotifera were absent at

Sites I through IV at some point during winter, but were

never found below 2.5/1 at Sites V and VI.

Calanoid copepods

Numbers of calanoid copepods (adults plus copepodids)

ranged from Oto 37/1, and similar seasonal trends were

seen at all sites (Fig. 9). Numbers decreased during the

fall of 1973 to 0/1 between October, 1973 and mid-March,

1974. Abundance of. calanoid copepods began to increase

again between late April and early June, 1974, and yearly

maxima were attained between mid-June and early September

at all sites.

Cyclopoid copepods

Cyclopoid copepods (adults plus copepodids), which

ranged from Oto 424/1, showed one or two summer peaks at

all sites (Fig. 9). A mid-to-late May peak occurred at all

sites, and a second summer peak was seen at Sites I and IV

in early August. Only at Site I were numbers greater in

August than in May. Slight winter maxima occurred between

mid-January and mid-February at Sites I through V. At

Site VI cyclopoid copepods increased gradually from late

November, 1973 until mid-May, 1974. Abundance of cyclopoid

copepods approached 0/1 at Sites I, II, and III between

January and March, whereas numbers were always greater than

1.0/1 at Sites IV, V, and VI.

Cop0pod nauolii

Numbers of copepod n~uplii ranged from Oto 583/1 and

exhibited similar seasonal trends at all sites (Fig. 9).

Copepod nauplii exhibited two su~mer peaks at all sites,

the first during mid-to-late May, and t~e second between

early August and early September. Copepod nauplii exhibited

winter peaks in February at Sites V and VI. At Sites I

through IV copepod nauplii reached 0/1 between February 1

and March 2, 1974, whereas minima of 0.4/1 at Site V and

6.4/1 at Site VI occurred on February 8, 1974 and November 11,

1973, respectively.

Minor taxa

Leptodora kindtii peaked in mid-to-late June at all

sites except Site V, at which a September peak was indi­

cated. Numbers of L. kindtii never exceeded 1.5/1, how­

ever. Macrothrix laticornis, Alona sp., Leydigia

quadrangularis, Camptocercus rectirostris, Pleuroxus

denticulatus, Harpacticoida, and Ostracoda were found in

such low numbers or of such spotty occurrence, or both,

that seasonal trends could not be detected (Appendix D).

Vertical differences

There was no significant difference between depths in

number per liter of most zooplankton organisms, based on

Van Dorn total data. Matched-t tests showed no significant

differences at the 95% significance level between total

... CD --... CD a. ... • -4 e :a

z

600

500

400

300

200

100

10

600

500

400

300

200

100

10

600

S00

400

300

200

100

10

s 0 N 1973

D J

26

Site I

Site II

Site Ill

I J 1974

J A s

Figure 9a. Numbers (Yan Dorn total, all depths averaged) of Calanoid copepods (~.,_- .. ), Cope pod naupl ii (_.-}, and Cycl opoid copepods ( •.•• ] at Sites I, II, and III of the Big Eau Pleine Reservoir during September, 1973 to September, 1974. Note the different scales for Oto 10, 10 to 100, and over 100.

... CD --,_ CD a.. ,_ • ..a e =-

%

600

500

400

300

200

100

600

500

400 300 200 100

10

600 500

400

300

200

100

10

s

27

0 N D J F 1973

Site IY

Site Y

Site YI

M A M 1974

J J A s

figure 96. Numbers (Van Dorn total, all depths averaged} of Calanoid copepods (---~), Copepod n~uplii ( __ ), and Cyclopoid copepods (····} at Sttes IV and V of the Big Eau Pleine Reservoir, and at Site VI oelow the· dam, during September, 1973 to September, 1974. Note the different scales for Oto 10, 10 to 100, and over 100.

28

r:iumbcr s or numbers of 0ny of ' :-ie r.1aj ;.:,.'.'.' :.:., . xa at 1 and 2. Sm

for Sites II through VI. At -ite I n 1 mrA~-rs of Daph_J]_i_~ SP,R•

and BoEmina l._ongirostris were signif:ica.ntly greater at 1m

than at 2.Sm. There were no significant differences

between total numbers or numbers of any of the major taxa

at 1 and Sm at Sites II, III, and VI, whereas at Sites IV

and V numbers of cyclopoid copepods were significantly

greater at 1 than Sm, and at Site IV numbers of

~• longirostris were significantly greater at 1 than Sm, at

the 9S% significance level.

Horizontal differences

A one-way analysis of variance showe~ no significant

differences in numbers per li~er among sites, based on the

#10 oblique Clarke Bumpus samples. For the Van Dorn total

samples, all depths averaged, there were no significant

differences in number per liter among sites except for

calanoid copepods; there were significantly fewer at

Site I than at Sites II through VI, at the 9S% significance

level.

Biomass

Seasonal trends in biomass (ash-free dry weight),

which ranged from 4 mg/m3 (0.13 kg/ha) to 950 mg/m 3 (34.17

kg/ha), were similar to those of total numbers and similar

at all sites (Fig. 10). A one-way analysis of variance

showed no significant difference in biomass among sites, at

the 95% level of significance. Initial summer peaks of

1000 Site I

100

·-. - 775 Site II

17S Site Ill _/•-...... ............ ____ /·-•, . ...-·"--. ► ... ___ • M 100 .\ & ..._

-=- ·-· e C:

71S ... Site IV ." /"'--. -... 11:1 -·- __,.•--· ·----· e 100 . \_. -~

all

77S Site Y .\ ; ........... /·"-.-----·--100 ---· ·--,. .

715 Sile YI • ✓✓•

·-·--· ·-... ,,,....-----.-·

100 .

........... ..--

S I O I N I D I J I F I M I A I M I J I J I A I S I

1973 1974

ffgure 10: Biomass in mg/m3 (log scale), based on #10 oblfque Clarke Bumpus samples, at Sites I through Vin the Big Eau Pleine Reservoir, and at Site VI beJow the dam, during September, 1973 to September, 1974.

3(.J

442 mg/m 3 (19.'.12 kg/ha) to 693 mg/m 3 (30.0 kg/ha) occurred

between late May and

(22.51 kg/ha) to 950

early July, and later peaks of 626 rng/m3

3 rng/rn (34.17 kg/ha) occurred between

August 5 and September S, 1974 at Sites I through v. At

Site VI peaks in biomass of 397 mg/m3 and 543 mg/m3 occurred

on July 2 and September S, respectively. Mean biomass for

September 20 through December 1, 1973 and May 13 through

September S, 1974 ranged from 325.3 mg/m 3 (12.0 kg/ha) to

375 mg/m3 (19.6 kg/ha) at Sites I through V, and was

239 mg/m3 at Site VI.

Comparison of the #10 Van Dorn and the #10 oblique Clarke Bumpus

Seasonal trends in total rr .. unbsrs per liter, when both

samplers were used during ice-free months, were similar at

all sites (Fig.' 6). Except at Site IV, total numbers were

not consistently higher for either the #10 Van Dorn (all

depths averaged) or #10 oblique Clarke Bumpus samples.

At Sites ·V and VI the mid-May #10 Van Dorn peak in numbers

was not duplicated by a #10 Clarke Bumpus peak, because a

mid-May Clarke Bumpus sample was not taken at these Sites

due to equipment malfunction.

In 49 out of 60 two-tailed matched-t tests there were

no significant differences in total numbers or in numbers

of any of the major taxa between #10 Van Dorn (all depths

averaged) and #10 oblique Clarke Bumpus samples. There

were no significant differences, at the 95% or greater

level, between the #10 Van Dorn and the #10 oblique Clarke

31

Bumpus in the :-iurnber I)r->r 1 i i:c·r of D.

~haeri~, or Rotifer-a collected at any of the sites.

Numbers per liter, based on the #10 Van Dorn samples, of

Daohnia ~• at Sites II, III, IV, and VI, of c. reticulata

at Site III, of B. lonairostris at Sites IV and V, of

calanoid copepods at Site V, of cyclopoid copepods at

Site VI, and of total numbers at Site IV were significantly

higher, at the 95% or greater level, than numbers per

liter of the same organisms based on the #10 oblique

Clarke Bumpus samples. Numbers per liter of copepod

nauplii based on #10 oblique Clarke Bu□pus samples were

significantly greater, at the 95% level, than number per

liter of the sa□e based on the #10 Van Dorn samples.

Comparison of #10 Van Dorn and Van Dorn total

Seasonal trends in total numbers per liter based on

#10 Van Dorn and Van Dorn total were similar at all sites

(Fig. 6). Small organisms, such as c. sphaericus, copepod

nauplii, and Rotifera, and those with narrow bodies, such

as cyclopoid copepods, were retained in significantly

greater numbers, based on two-tailed matched-t tests, by

the #200 soil screen (Van Dorn total) than by the #100

soil screen (#10 Van Dorn). Organisms with larger bodies

or large antennae, or both, such as calanoid copepods,

Daphnia spo., D. leuchtenberaianum, a~d c. reticulata,

passed through the mesh openings of the #100 soil screen

less easily. Number per liter, based on Van Dorn total,

of copepod nauplii, •JC1c,r,o:irl copc-pc,ds, f.;utifr-:-ra, ,:1nd t~otal

numbers at all sites, of~. ,:"o_:)f_l_~5 __ricus at Sites II through

VI, of calanoid copepods at Sites II, IV, ~nd v, of

B. longirostris at Sit~s I, II, III, and VI, and of Daohnia

spp. at Sites III, V, and VI were significantly greater, at

the 95% or greater level, than numbers of the same based on

#10 Van Dorn samples. There were no significant differences,

at the 95% level, between the #10 Van Dorn and Van Dorn total,

in the number per liter of Diaphanosoma leuchtenbergianum

or£• reticulata at any of the sites.

The #200 soil screen (Van Dorn total) retained between

13.8 and 1467.0% more of the small organisms (C. sphaericus,

copepod nauplii, and Rotifera), and 8.1 to 28.0% more cyclo­

poid copepods than did the #100 so~l screen (#10 Van Dorn)

at all sites (Table 2).

Relationships between physical and chemical characteristics and zooplankton numbers

Numbers of most zooplankton taxa were not significantly

correlated with water temperature at more than three of the

six sites (Appendix H). Only depth of water at the dam,

total numbers, and number per liter of Daphnia fil?.E.•,

Q• leuchtenbergianum, copepod nauplii, and calanoid copepods

were significantly correlated with water temperature at more

than half of the six sites. Depth of water at the dam, total

numbers, and number per liter of Daphnia .§.££• were signifi­

cantly positively correlated, at the 95% or greater level,

with water temperature at all sites. Also, number per liter

.:S.:S

Table 2: The percent more organisms retained by the #200 soil screen (Van Dorn total) than by the #100 soil screen (#10 Van Dorn), based on yearly averages, all depths averaged.

Site I Site II Site III Site IV Site V Site VI

Daphni~ spp. 0.7 1.7

Q. reticulata 5.4 o.o

:Q. leuchtenbergianum 0.4 0.4

1!• long1rostr1s . 1 o. 5 .3. 6

M. laticornis* .3.3.3 o.o

1• guadrangularis* .350.0 800.0

Q. sphaericu; .30. 5 .34- 7

~. kindtii * O. O o. 0

Calanoid copepods 2.9 2.7

Copepod nauplii

C7clopoid copepods

Rotifera

Ostracoda*

Total numbers

845.1 11.3.3. 5

28.0 '26.1

489.8 Z72.4

600.0 o.o

108.2 121.2

0.1

5.8

0.2

0.7

o.o

o.o

22.s

o.o

1.2

998.8

1.3.1

495.9

o.o

•·=minor taxa, occurring in small numbers. Inf.= infinity.

o.o

o.o

o.o

o.o

Inf.

105.9

0.9

o.o

o.o

5.8

o.o

o.o

13.8

o.o

0.7

0.9

o.o

o.o

o.o

o.o

20.6

o.o

o.o

10.6 s.1

285.0 556.3

100.9 133.2

of copepod nauplii at Sites I, II, III, IV, and VI, and

number per liter of calan0id c0pepods ~t Sites I, II, IV,

v, and VI, were significantly positively correlated, at the

95% or greater level, with water temperature.

As with water temperature, numbers of most zooplankton

taxa were not significantly correlated with depth of water

at the dam at more than half of the six sites (Appendix H).

Variables that were positively correlated, at the 95% or

greater significance level, with depth of water at the dam

were water temperature and number per liter of Daphnia .§.PE.•

at all sites, water transparency and number per liter of

copepod nauplii at Sites II through VI, and dissolved oxygen

at Sites II through v. For variables that were cor~elated with both water

t~mperature and depth of water at the dam, partial correla­

tion analyses were made to determine which factor, water

temperature or depth of water at the dam, was more important.

These analyses indicated that numbers of Daphnia ~- at

all sites, numbers of calanoid copepods at Sites I, II, IV,

and VI, and numbers of copepod nauplii at Sites I, II, IV,

and VI were really correlated with water temperature and

not depth of water at the dam. Numbers of copepod nauplii

at Site III, and dissolved oxygen at Sites II through V, on

the other hand, were more closely correlated with depth of

water at the dam than with water temperature.

Only numbers of a few zooplankton taxa were correlated

with water transparency at a majority of the sites (Appendix H).

Cyclopoid copepods w~re significantly positively correlated,

at the 95% or greater level, with water transparency at

Sites II through VI, whereas numbers of D. leuchtenbergian~

at all sites, and numbers of£• sphaericus at Sites I, II,

III, IV, and VI were significantly negatively correlated,

at the 95% or greater level, with water transparency.

No zooplankton taxa was significantly correlated at a

majority of sites with either dissolved oxygen or depth of

sample.

Correlations among numbers of taxa

Most significant correlations among numbers of

various taxa occurred at three or less of the six sites

(Appendix H). Considering only correlations among taxa

that were significant at four or more of the six sites, .···\i

·· numbers of Daphnia .2.E.£• were significantly positively

correlated, at the 95% or grea·ter level, with numbers of

!2.• leuchtenbergianum and B. longirostris at Sites I, IV, V,

and VI, and with numbers of copepod nauplii at Sites I

through IV. Numbers of Ceriodaphnia reticulata were signi-

ficantly positively correlated, at the 99% level, with

numbers of Chydorus sphaericus at Sites I through v.

Numbers of !2.• leuchtenbergianum were significantly posi-

tively correlated, at the 95% or greater level, with numbers

of£• sphaericus and~- longirostris at Sites II through VI.

Numbers of~- longirostris were also significantly posi­

tively correlated, at the 95% or greater level, with numbers

of£• sphaericus at Sites II through VI. Numbers of copepod

36

nauplii were signific~ntly positively correlated, at the

95% or greater level, with cyclopoid copepods at Sites I

through V.

37

DISCUSSION

Physical and chemical characteristics

The absence of thermal stratification in the Big Eau

Pleine Reservoir can be attributed to the effects of wind

in a shallow basin and probably somewhat to the loss of

water from the hypolimnion during the summer. Benson and

Cowell (1968) found a lack of thermal stratification in

Lewis and Clarke Lake, a shallow, fluctuating, Missouri

River Reservoir. Hanebrink (1965) stated that removal of

water from below the thermocline may cause a reduction or

total loss of the hypolimnion and thermocline, and thus a

loss of stratification.

Due to the eutrophic nature of the Big Eau Pleine

Reservoir (Shaw, 1976, unpublished), a reduction in dis­

solved oxygen in the deeper water would be expected. The

oxygen stratification found during the summer of 1974

would probably have been more pronounced if the reservoir

had been thermally stratified.

The low water transparency in the reservoir may be

partly due to the drawdown. Axelson (1961) stated that

one of the effects of reservoir drawdown is the stirring

up and suspension of sediments, especially by ice during

low water.

.Spccie_.s composition

All species found in the Big E~u Pleine Res~rvoir are

common to other bodies of water of the Great Lakes area

(Brooks, 1957, 1959; Marsh, 1929, 1933; Wilson, 1959;

and Yeatman, 1959); ther~fore, the species composition of

the Big Eau Pleine Reservoir appears to have been little

affected by the drawdown. The relatively homogeneous

horizontal nature of species composition in the Big Eau

Pleine Reservoir may be due to the homothermous condition

of the reservoir, and to a lack of rooted aquatic plants

throughout most of the reservoir.

Several organisms that are generally associated with

aquatic plants were found only at Site I. Approximately

200m upstream from Site I was a shallow bay containing

rooted macrophytes. Camptocercus rectirostris and

Pleuroxus denticulatus, found only at Site I, and Macrothrix

laticornis, found only at Sites I and II, are littoral or

benthic.in nature, or both, and are generally associated

with aquatic plants (Yeatman, 1956; Keen, 1973; Applegate

and Mullan, 1967).

Total numbers

The annual mean number (Van Dorn total, all depths and

Sites I through V averaged) of 298 zooplankton per liter in

the Big Eau Pleine Reservoir ranked 4th in a comparison

with the average density in 22 other bodies of water (Table

3). Mean annual total zooplankton numbers in the other 22

39

bodies of water ranged frcD 4.5/1 in Lake Superior (Selgeby,

1975) to 1436/1 in Gaynor Lake, Colorado (Pennak, 1949).

Mean annual total zooplankton number in eutrophic Lake Erie

was 61.4/1 (Watson and Carpenter, 1974).

Annual fluctuations in zooplankton number

The annual fluctuation in total numbers of zooplankton

in the Big Eau Pleine Reservoir was similar to that in

other bodies of water. As in the Big Eau Pleine Reservoir,

zooplankton numbers reached maxima in the summer in Lakes

Erie and Ontario (Watson and Carpenter, 1974), Bull.Shoals

Reservoir (Applegate and Mullan, 1967), and Lake Superior

(Selgeby, 1975). Soap Lake and Lake Lenore, Washington

(Anderson et. al., 1955), and Fayetteville Green Lake in

New York (Culver and Brunskill, 1969) exhibited two summer

peaks in total numbers, as did the Big Eau Pleine Reservoir.

As in the Big Eau Pleine Reservoir, zooplankton numbers

reached minima during winter in Lake Superior (Selgeby, 1975),

Lakes Erie and Ontario (Watson and Carpenter, 1974), Soap

Lake and Lake Lenore (Anderson et. al., 1955), and

Fayetteville Green Lake (Culver and Brunskill, 1969).

Species percent composition

As in the Big Eau Pleine Reservoir, Rotifera and copepod

nauplii, and, less commonly, Chydorus sphaericus, have been

found to comprise a substantial portion of total zooplankton

numbers in many other bodies of water. Rotifers were the

Table 3: Mean monthly and mean annual number per liter of zooplankton in the Big Eau Pleine Reservoir and other bodies of water.

Net Y!'llrly Body o! Wilter Size Jan. P'eb. Mar. Apr. Mily June July Aug. Sept. Oct. Nov. Dec. Mean Reference

Big Eau ~leine Reservoir 10 30.9 25.0 6.7 2.4 281.7 134.0 127.0 268.0 384.0 270.0 43.4 48.7 145.0 Present study, Site,- I - v. 20. 32 km 20 105.0 40.0 ll.6 10.6 694.0 ~64.0 ,14'.'.0 598.0 607.0 363.0 79.0 112.0 298.0 All depths av·eruced.

Dea,·er R~scrvoir 10 4.0 3.2 22.6 16.0 11.3 0.8 14.!il 27.8 '26.9 27.0 12.2 16.6 Applegate and Mullan, 1967 114.2 km

null Sho~ls Rcnervoir 10 7.7 15.5 20.8 23.5 17.6 6.5 10-l.O km

2.4 2.s 4.9 7.8 15.6 Applegate and Mullan, 1967

LP-wis ang Clnrke Lake 26.t 14.6 10.2 1G.2 ~0.8 33.5 6.6 2.6 2.4 3.0 22.0 71. 5 20,8 Benson and Cowell, 1Q68 l_}0.0 km"

Keystone Hcservoir 106.7 186.7 623.7 135.0 123.3 125.0 12.3 04. 3 41.3 54.3 31. 7. 41.7 130.5 J<och~lek rt. al., 1971

Lake Oilhe 2 20 43.9 137, 9 92. 4 44.6 23.9 23.7 61.1 Selgeby, 1974 1 ~21. 4f, km

Lake Fo2t Smith 25 9.0 10.s 3.0 19.0 14.3 22.2 14.2 53.2 116.5 51.3 10.5 32.0 35.0 Hoffman -,t. al., 1!152 2.13 km

Turkeyfoot Lake 912. 7 292.0 296.7 1207.0 1555.0 279.5 1031.5 411. 3 422.0 449.(1 373.0 700.0 644.1 Y..rnatz • 1941

Horse tooth Resl'!rvoir 6.0 11.0 16.0 41.0 129.0 85.0 139.0 94.0 94.0 12.0 40.0 8.0 54.1 Rec:d and Oli"c, 1956

Pymatun1ng R,:,s.,rvoir 17 292.0 llorccky, 1956

Gaynor ~ake 20 143G.O P~nnak, 1949 0 9 k:n

Baselin! Reservoir 20 582.0 Pannu.k, 1949 3 km

Table (continued) : Mean monthly and mean annual number per liter of zooplankton in the Big Eau Pleine Reservoir and other bodies of water.

Nat Yrarly Body of Water S1:r.e Jan. Feb. Mar. Apr. Play June July Aug. Setpt. ~I:. Nnv. Dec. Meun lleference

Hayden•~ Lake 20 274.0 r~1_,nek., 19-19 0.15 km

Kossler2Lake 20 52.0 rennak, 1949 0.05 km

Lake St. 2Cla1re 20 28G.O Leach, 1973 1 110 lcm

Fayetteville Green Lake 20 23.S 42.9 56.6 73.8 46.1 161.0 52.8 132, 3 68.0 35.2 69.2 Culver 11.nd t\runsk:111, 196~

Lake Rathbun 58.2 30.8 1.0 1.e 10.e Mi».yhew, 1"75 Uncuhli ~:hr·d

..:, Lal:e Lr2ore 16.0 a.o o.o 6.0 120.0 90.0 245.0 97.0 98.5 29.0 43.5 12,5 64.4 /\nderson et. al., 19SS I--s.~6 1:n·

Soi>ip Lii~e 1.0 2.0 o.o 6.0 75.0 12.s 35.3 24.5 27.5 13.0 9.0 1.0 17.2 Ander!ion et. al., 1955 J.36 l:m

Lake Er1c2 25 12. 5 16.2 204.0 142.3 72.1 46.9 18.7 25.0 14.8 61.4 Wataon nnd Ciirpenter, 1974 25 021 k,.

Lar.e 0nt11~io 25 1.3 2.1 2.0 8.2 46.6 7.3 27.6 54.7 35.1 42.4 t'S.6 6.) 16. 7 Watson and Car;,cntec, 1'>7-: 19.0'l9 l:m

Lol::c l'uro, 25 2.) 2.2 4.3 10.0 '13.5 20.8 11.0 8.8 9.2 Watson and Cacpc-nter, 1971 S9.S70 b,,

LAka Supesior 10 2.9 2.4 1.s 1.4 1.4 3.2 15.S 11.) 4.6 2.9 2.8 4.5 Selgeby, 1975 b 7 km

42

most c:o:nmon zooplc1nkL0rs in Vr:.:ystoni::c Fc:::ervoir, Oklahoma

(Kochsiek et. al., 1971), in Lewis and Clarke Lake, South

Dakota (Siebrass, 1961), and in Lake St. Claire, Ontario,

where they comprised 46% of lotal numbers (Leach, 1973).

In Lake Oahe copepod nauplii comprised about 55%, cyclopoid

copepods 22%, calanoid copepods 8%, and cladocerans about

15% of Crustacean numbers (Selgeby, 1974). Rada (1970)

found that Daphnia ~• and copepod nauplii comprised more

than 95% of the zooplankton standing crop in Big Bend

Reservoir, South Dakota. In Great Slave Lake copepod

nauplii comprised nearly 50% of the Entomostraca counts

(Rawson, 1956).

Chydorus sphaericus, found in densities of up to 567/1

in the Big Eau Pleine Reservoir, was present in high numbers

in at least one other study. In Pymatuning Reservoir,

Pennsylvania, C. sphaericus was present in substantial

numbers throughout the year, and numbered as high as

several thousand per liter in July or August (Borecky, 1956).

Keen (1973) stated that Chydorids such as c. sphaericus

are typically littoral and associated with plants, but

this was not the case in the Big Eau Pleine Reservoir.

paphnia .2.E.E.•

The seasonal pattern of summer peaks in numbers of

Daphnia .21?.E.• in the Big Eau Pleine Reservoir was similar to

that found by other authors. In Pymatuning Reservoir,

Borecky (1956) reported maxima of several hundred Daphnia

spp./1 in June and late August or early September. Selgeby

( 1968) reported rr.axirnum numbers of Da.:::;r ni_a pulcx in e>arly

su1Timer and Daoh~ia aaleata ~-g_~tae in late sumr..er in Lake

Francis Case. Daphnia ~- numbers peaked in June of 1966,

June and July of 1967, and during June through August of

1968 in Big Bend Reservoir (Rada, 1970).

Ce~iodaphnia reticulata

As in the Big Eau Pleine Reservoir, Ceriodaphnia

reticulata often was present only in low numbers in other

bodies of water and exhibited highest numbers during the

summer. Applegate and Mullan (1967) found that Ceriodaphnia

.2.E.E.• peaked at 9.2/1 in August, 1965 in Beaver Reservoir,

and at 0.7/1 in June, 1965 and 2.4/1 in June, 1966 in Bull

Shoals Reservoir. In Pymatuning Reservoir, Borecky (1956)

found c. reticulata few in number until July when it

increased to an August maximum of several hundred per liter.

Wells (1960) found Ceriodaphnia .§.£• in low numbers in

summer and fall samples in Lake Michigan.

Diaphanosoma leuchtenbergianum

As in the Big Eau Pleine Reservoir, Diaphanosoma

leuchtenbergianum exhibited sumMer or fall peaks in other

bodies of water. £· leuchtenbergianum numbers peaked at

8.7/1 in mid-August in Beaver Reservoir and at 0.5/1 in

mid-June in Bull Shoals Reservoir (Applegate and Mullan,

1967). In Lake Fort Smith, Arkansas,£. leuchtenbergianum

was present only during October when it exhibited a peak

of 6/1 (Hoffman and Causey, 1952). Pennak (1949) found

44

1:hAt D. J.euchte:nberaia_~ was cc:-:-imon in Allen, B2seline,

Beasley, and Boulder Lakes, Colorado, and that maximum

numbers occurred in August and September.

Bosmina longirostris

McNaught (1975) classified~- longirostri~ as a late

eutrophy organism. Pennak (1949) stated that~• longirostris

is usually considered a spring and early summer form.

Bosmina longirostris showed summer peaks in numbers

in other reservoirs as it did in the Big Eau Pleine Reservoir.

B. longirostris peaked in mid-May at 1000 or more p~r liter

in Pymatuning Reservoir, and exhibited a smaller second

peak in mid-July (Borecky, 1956). Selgeby (1975) found

peak numbers of~• longirostris in late July, but none

during winter samples in Lake Superior. In Lake Ontario,

where it was the dominant cladoceran, ~• longirostris

exhibited peak numbers during late August (McNaught, 1975).

Chydorus sphaericus

Keen (1973) stated that Chydorids are principally lit­

toral. Vallentyne (1974) classified£• sphaericus as an

indicator of extreme eutrophy.

Chydorus sphaericus occurred in peak numbers during

summer in many bodies of water, including the Big Eau Pleine

Reservoi•r. Borecky ( 1956) found £• sphaer icus in large

numbers throughout the year in Pymatuning Reservoir, with

a maximum in July or August of up to several thousand per

liter. In Georgian Bay, Ontario, which is not eutrophic,

45

Carter (1971) found c • .:~:acFicus to be sc,nce except in

late summer and early fall. In Lake St. Claire

c. sphaericu! was most abundant during June (Leach, 1973).

c. sphaericus exhibited peak numbers in March or April and

during the fall in Lawrence Lake, Michigan (Keen, 1973).

Rotifera

Numbers of Rotifera generally exhibit one or two peaks

per year in most bodies of water, as in the Big Eau Pleine

Reservoir, with at least one of the peaks during the summer.

Benson and Cowell (1968) reported maximum numbers of rotifers

in June and minimum numbers in November in Lewis and Clarke

Lake. Rotifer numbers peaked in June ~nd August in Lake

St. Claire (Leach, 1973), in May and August in Horsetooth

Reservoir (Reed and Olive, 1956), and in September in Lake

Fort Smith (Hoffman and Causey, 1952).

Calanoid copepods

As in the Big Eau Pleine Reservoir, peak numbers of

calanoid copepods occurred during the summer in other

bodies of water. Calanoid copepod numbers peaked in April

and October, 1965 in Beaver Reservoir, and in May of 1965

and 1966 in Bull Shoals Reservoir (Applegate and Mullan,

1967)~ In Lake Francis Case Diaptomus numbers reached

maximum numbers in mid-June (Benson and Cowell, 1968). In

Lake Fort Smith Diaptomus pallidus was present throughout

the year and exhibited pulses in September through December

(Hoffman and Causey, 1952). Rada (1968) reported that the

standing crop of ~J:cm1:s wns low i..n c,,:;_rly spring, peaked

in June, and decreased the rest of the ~ampling year

except in August in Big Bend Reservojr. Di.apto~ exhibited

peaks in late July, late August, and possibly late September

in Great Slave Lake (Rawson, 1956).

Cyclopoid copepods

Seasonal trends in cyclopoid copepod numbers in the

Big Eau Pleine Reservoir were similar to trends in other

bodies of water. Cyclops bicuspidatus thomasi was present

throughout the year in 7 Colorado lakes and exhibited

spring peaks in numbers in 4 of them (Pennak, 1949).

Selgeby (1968) found that£•£• thomasi and Mesocyclops

edax reached maxima during early summer in Lake Francis Case.

Cyclopoid copepod numbers peaked in late August in Lake

Superior (Selgeby, 1975). In Georgian Bay, Ontario cyclo­

poid copepods peaked in late July to early August and in

December; Cyclops vernalis and~- edax reached maxima in

late summer or autumn, whereas£•£• thomasi was abundant

all summer and in December (Carter, 1971). In Lake st.

Claire cyclopoid copepod numbers peaked in July (Leach,

1973). Rada (1970) found Cyclops to exhibit peak numbers

in July and October in Big Bend Reservoir.

Copepod nauplii

As in the Big Eau Pleine Reservoir, maxima of copepod

nauplii occurred during summer or fall in other bodies of

water. Cyclopoid nauplii were most abundant from June

through Septemb~r and c.l(]rJin in early Dr~cr,~,bc,r in Gt?or,Jian

Bay (Carter, 1971). Copepod ~auplii were present throughout

the year in Lake Fort Smith, and exhjbitert peaks in S0ptember

and October (Hoffman and Causey, 1952). In Great Slave lake

copepod nauplii made up nearly 50% of the Entomostraca

counts, and had a single main peak in mid-July (Rawson,

1956).

Minor taxa

Macrothrix laticornis, Alona §.E.•, Leydigia quadrangularis,

Camptocercus rectir·ostris, Pleuroxus denticulatus, and

Leptodora kindtii, found in low numbers in the Big Eau

Pleine Reservoir, were also found in low numbers in other

studies. In 340 lakes and ponds in the Canadian Rockies,

Alona El?.E.• were uncommon, Macrocyclops §.E.• tended to be

infrequent, and Pleuroxus .§12£• occurred infrequently and

at low densities (Anderson, 1974). Pleuroxus denticulatus

and Macrocyclops albidus were found in small numbers in

Woods Reservoir and were associated with vegetation (Yeatman,

1956). Selgeby (1974) found Leydigia guadragularis in low

numbers in Lake Oahe. Macrocyclops albidus and §_ucyclops

agilis were present only in small numbers when they occurred

in the Waterton Lakes in Alberta, Canada (Anderson and

Green, 1975). Applegate and Mullan (1967) stated that

Alona, Leydigia, Pleuroxus, and Camptocercus are genera

generally associated with littoral waters, and this may

explain their low numbers in the Big Eau Pleine Reservoir,

48

where only channel stcttions were cho~~n, and where the

littoral zone is reduced by low transparency. Hall (1964)

found peak numbers of Lc~Dl.odora kindl ii of only 0.15/1 in

Base Line Lake.

Vertical differences

Difference in numbers at various depths is quite

common in other bodies of water, especially in those that

show strong thermal stratification during summer. More

than 50% of the plankton in Great Slave Lake was found in

the upper 25m (Rawson, 1956). Benson and Cowell (1968)

found Daphnia _rn. and calanoid copepods in the greatest

density near the surface in Lake Fr2ncis Case. Den'gina

(1967) attributed higher zooplankton concentrations in the

upper 10 to 25m in Lake Ladoga, USSR, to stratification,

with zooplankton development in the hypolimnion limited by

low temperatures.

Benson and Cowell (1968) found no significant differ­

ences in total numbers of zooplankton among depths in

thermally unstratified Lewis and Clarke Lake. In Base Line

Lake under homothermous conditions nearly equal densities

of Daphnia were found from surface to bottom, but after

stratification the majority of Daphnia .§.EE.• were found in

the epilimnion and thermocline (Hall, 1964).

Horizontal differences

Whereas in the Big Eau Pleine Reservoir there were

usually no significant differences in numbers among sites,

in many other bodies of water, especially larger, deeper

bodies of water, horizontal differences in numbers are

common. In Lake Oahe mean crustacean density generally

increased from the lower end of the reservoir, near the dam,

to the upper end of the reservoir (Selgeby, 1974); clado­

cerans were most abundant in the upstream portion, and

copepods in the downstream portion of the reservoir.

McNaught (1975) found that cladocerans were most abundant

close to shore, whereas the copepods preferred deeper

waters in Lake Ontario. The upstream stations in Big Bend

Reservoir had relatively low standing crops when compared

to the three deeper downstream stations (Rada, 1970). In

Lake Francis Case calanoid copepods were relatively more

abundant upstream than downstream (Selgeby, 1968).

Kochsiek ·et. al. (1971) found rotifers to be more numerous

in the upstream portion of Keystone Reservoir than in the

downstream portion.

Biomass

Zooplankton biomass (ash-free dry weight) in the Big

Eau Pleine Reservoir was high when compared to that of other

bodies of water (Table 4). The mean biomass (#10 oblique

Clarke Bumpus, Sites I through V averaged) in the Big Eau

Pleine Reservoir from September 20 through December 1, 1973

3 and from May 13 through Septembers, 1974 was 362 mg/m

,le 4: Biomass (mg/m3 ) in the Big Eau Pleine Reservoir and other bodies of water.

Body of Water

Eau Pleine Reservoir

rer Reservoir

. Shoals Reservoir

•on Ferry Reservoir

Erie

Ontario

Huron

Superior

Lake

t Bear Lake

t Slave Lake

deer Lake

arte

Net Area Size

28.32 k:m2 10

114.2 Ian2 10

184.0 km2 10

25 1 821 km2

2 19,099 km

2 591 570 Ian

2 82,367 km

2 0.10 lan

2 3 1153 km

2 22,500 lan

2 51 569 km

2 1,707 km

20

25

25

25

10

20

20

20

20

20

Period Sampled

May - Dec.

Fab. - Dec.

Jan. - Nov.

Sept. - Oct.

A_pr. - Dec.

Jan. - Dec.

Apr. - Dec.

Jan. - Dec.

July

July or August

July or Aur,ust

July or Aua,ust

July or August

Biomass for Period

3 362 mg/m

3 33.4 mg/m 3 2n.2 mg/m

377.0

171.2

3 mg/m 3 mg/m

3 67.7 me/m 3

75.5 me/m

3 18.6 mn/m

3 67.4 mg/m

3 13.0 mg/m

3 7 - 70 mg/m

3 57.0 mg/m

3 76.0 mg/m

Type of Biomass

Ash-free dry wt.

. Dry wt.

Dry wt.

Dry wt.

Ash-free dry wt.

Ash-free dry wt.

Ash-free dry wt.

Ash-free dry wt.

Ory wt.

Wet wt.

Het wt.

Wet wt.

Wet wt.

Reference

Present study

Appleeate and Hullan, 1967

Applccate ancl Hullan, 1967

Wright, 1958

Watson and Carpenter, 1974

Watson and Carpenter, 1974

Watson and Carpenter, 1974

Selgeby, 1975

Olsen et. al., 19 6 7

Patalas, 1975

Patalas, 1975

Patalas1 1975

Patalas, 1975

(13.8 kg/ria). Lc1kcs Erj~ 2nd ll1Jron had biomaf,S (,,sh-free

dry weight) fficans of 171 mg/m 3 and 75.5 mg/m 3 , respectively,

for a comparable period (Watson and Carpenter, 1974).

Oligotrophic Lake Superior had a mean annual biomass (ash­

free dry weight) of only 18.6 mg/m 3 (Selgeby, 1975).

As in the Big Eau Pleine Reservoir, peak zooplankton

biomass occurred during the summer in other bodies of water.

Maxima in biomass occurred in mid-July in Lake Ontario, in

early June in Lake Erie, and in late July in Lake Huron

(Watson and Carpenter, 1974). Applegate and Mullan (1967)

found maximum zooplankton biomass in June in Beaver Reser­

voir, and in May in Bull Shoals Reservoir.

Comparison of samplers

Results of this study indicate that similar estimates

of zooplankton numbers could be obtained from either the

Van Dorn or Clarke Bumpus as the sole sampling device.

There were no significant differences in numbers per liter

in 49 of the 60 comparisons between the #10 Van Dorn and

the #10 oblique Clarke Bumpus, and number per liter based

on these two samplers showed similar trends when both

samplers were used during the ice-free months. Except for

Daphnia fil2.P.• which were collected in significantly greater

numbers by the #10 Van Dorn than by the #10 oblique Clarke

Bumpus at 4 sites, no zooplankter was collected in signi­

ficantly greater numbers by either the #10 Van Dorn or

#10 oblique Clarke Bumpus at more than two sites.

F<elationships b(:twc.en physical 2nd chcr~,i_cal characteristics and zoo pl an}: ton numbr~r s

As in the Big Eau Pleine Reservoir, numbers of zoo­

plankton have been found to be positively correlated with

water temperature in several other studies (Berg, 1974;

Hazelwood and Parker, 1961; June, 1974; Mayhew, 1975;

Patalas, 1975; Rawson, 1956). In the present study, total

numbers and numbers of Daphnia .§12£•, Diaphanosoma

leuchtenbergianum, copepod nauplii, and calanoid copepods

were significantly positively correlated with water tempera­

ture at a majority of the sites.

The significant positive correlation between depth of

water at the dam and water te·,;:,erature a:: all sites in the

Big Eau Pleine Reservoir prob2tly was not due to a cause

and effect relationship between these two factors, but to

coincidental seasonal variations of water level and tempera­

ture (i.e. high water and temperature in summer and low

water and temperature in winter).

The yearly drawdown in the Big Eau Pleine Reservoir

appeared to have little effect on the zooplankton popula­

tions. The effect that reservoir drawdown has on zoo­

plankton populations depends on 1) the flushing rate or

replacement quotient of the lake or reservoir, and 2) the

time of the year that the reservoir is drawn down. The Big

Eau Pleine Reservoir had a 30-year mean annual flushing

rate of 158 days (Wisconsin Valley Improvement Co.,

personal communication), which is well above the flushing

rate of 15 to 18 days considsind limiting to plankton by

Johnson (1964) and Brook and Woodward (1956). A winter

drawdown, as found in the Big Eau Pleine Reservoir, appears

to have less effect on zooplankton than a drawdown during

the warm summer months (Axelson, 1961).

Several authors have reported a positive relationship

between flushing time and zooplankton abundance. Johnson

(1964) found that the shorter the time required for com­

plete flushing in Babine Lake, western Canada, the lower

the mean standing crop of zooplankton. He found the rela­

tionship to be non-1inear, and the effect on zooplankton

standing crop was much greater when the flushing rate was

less than 15 days than when it was longer. Brook and

Woodward (1956) reported a stable, year-round plankton

population in Loch Kinardochy, Scotland, which had a flush­

ing rate always greater than 70 days, whereas in Lochan an

Diam, which had a flushing time of always less than 31 days,

the plankton population was present for only a short period

during the year. In Lochan an Diam zooplankton appeared

only when the flushing rate was more than 18 days. Siebrass

(1961) attributed a low mean number of net plankton per

liter in Lewis and Clarke Lake to its low retention time

of 8 to 10 days.

A winter drawdown appears to have less effect on zoo­

plankton than a drawdown during the warm summer months.

Axelson (1961) stated that a high rate of discharge during

the growth period, especially in July and August, causes a

decrease in the zooplc,nkton, •,,.;hereos the lowering of a 1 ake

in winter does not affect the zooplankton to any great

extent. In Lake Oahe, when the discharge rate was abruptly

increased in July, 1969, there was a reduction in zooplank­

ton at the downstream stations (June, 1974). Rodhe (1964)

stated that the regulation routine ordinarily used in Lake

Ransaren, Sweden (i.e. retention from spring to late summer,

and discharge in winter), would be more favorable to plankton

than the natural rhythm of water replacement (i.e. highest

discharge in spring and summer).

The low dissolved oxygen concentrations, which ·occurred

in the Big Eau Pleine Reservoir during January and February,

could have had adverse effects on at least the Daphnia .§l?.12.•

and Diaptomus §1?...2.• populations. Although dissolved oxygen

was not significantly correlated with numbers of any organ­

isms at more than 3 sites in the Big Eau Pleine Reservoir,

other authors have found zooplankton-oxygen relationships.

Fast (1971) found that zopplankton can be limited to shallow

depths by hypolimnion stagnation and thermal stratification.

In Kepple Lake, Washington, density of Daphnia and Diaptomus

was positively correlated with dissolved oxygen (Hazelwood

and Parker, 1961).

The positive correlation of dissolved oxygen at Sites

II through V with depth of water at the dam suggests that

reservoir drawdown results in a reduction of dissolved

oxygen, but this relationship has not been reported else­

where. Low dissolved oxygen during the winter in the Big

Eau Pleine Reservoir is probably due to a combination of

the low di~,solvf'."d oxygr-n in ·,i,;'lr_.,i-.:1.ng ,.-.,,::.' .. rrs (Sh,-1w, pPrsor1al

communication) and a r~ductjon in pholosynthesis caused by

reduced light penetration due to snow cover. Other con­

tributing factors are the upt~ke of oxygen by the sediments

from a much reduced volume of water, high BOD (Shaw, 1976),

and respiration by organisms.

The effects of water transparency and turbidity on

zooplankton seem inconsistent in the Big Eau Pleine Reservoir

and in other bodies of water. In the Big Eau Pleine

Reservoir numbers of cyclopoid copepods at Sites II through

VI were positively correlated with water transparency,

whereas numbers of Chydorus sohaericus at Sites I, II, III,

IV and VI, and of Diaphanosoma leuchtenberaianum at all

sites were negatively correlated with water transparency.

Taylor (1968) stated that both nutrient depletion and auto­

shading (due to silting) will cause a decrease in the phyto­

plankton standing crop and possibly a decrease in zoo­

plankton populations in late June and early July. In Lake

Oahe, June (1974) found a significant negative correlation

between zooplankton abundance and turbidity. On the other

hand, in Keystone Reservoir zooplankton species diversity

was positively correlated with turbidity at a majority of

sites (Kochsiek et. al., 1971).

CONCLllSIONS

1) Zooplankton specic-s composilion in the Big Eau Pleine

Reservoir was typical for lakes of the Great Lakes

Region, and, therefore, did not appear to be adversely

affected by the water level fluctuations.

2) No adverse effects of the water level fluctuations on

zooplankton number per liter and biomass were observed

in the Big Eau Pleine Reservoir. Number per liter and

biomass of zooplankton was high in comparison with

those in most other bodies of water.

3) The reservoir, probably d~e tc a lack of horizontal and

vertical thermal stratification, had little horizontal

or vertical differences in zooplankton number per liter,

and no significant horizontal differences in zooplankton

biomass.

4) Zooplankton number per liter and biomass had summer maxi­

ma and winter minima in the Big Eau Pleine Reservoir, as

is common in other bodies of water.

5) The yearly drawdown appeared to have little affect on

the zooplankton populations because: a) the 30-year

mean annual flushing rate of 158 days is considerably

greater than that thought to be limiting to zooplankton

by Johnson (1964) and Brook and Woodward (1956), and

b) a winter drawdown, as in the Big Eau Pleine

Res<::rvoir, occurs when zcr0 pla1--,l:tc,n L'Jf!::j(:rs are low, and

has less affect than if it occurred during summer when

zooplankton numbers ar~ h.igh.

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59

Carter, J. c. H. 1971. Distribution 2nd abundance of planktonic Crustacea in ponds near Georgian Bay (Ontario, Canada) in relation to hJdrography ~nd water chemistry. Arch. Hydrobiol. 68(2): 204 - ?31.

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Hazelwood, D. H. and R. A. Parker. 1961. Population dynamics of some freshwater zooplankton. Ecology 42(2): 266 - 274.

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June, F. c. 1974. Ecological changes during the transi­tional years of final filling and full impoundment (1966 - 70) of Lake Oahe, an upper Missouri River storage reservoir. u. s. Fish and Wldl. Service Tech. Paper No. 71. 57p.

bO

Keen, R. 1973. A probabilistic approach to the dynamics of natural populations of the Chydoridae (Cladocera, Crustacea). Ecology 54(3): 524 - 534.

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Kraatz, w. c. 1941. Quantitative plankton studies of Turkeyfoot Lake, near Akron, Ohio. Ohio J. Sci. 41(1): 1 - 22.

Leach, J. L. 1973. Seasonal distribution, composition and abundance of zoo€~ankton in Ontario waters of Lake st. Clair. Proc. 16 Conf. Great Lakes Res. pp. 54 - 64.

Marsh, c. D. 1929. Distribution and key of the North American copepods of the genus Diaptomus, with the description of a new species. Proc. u. s. Natl. Museum 75(14): 1 - 21.

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Martin, R. o. R. and R. L. Hanson. 1966. Reservoirs in the United States. Geol. Surv. Water Supply Paper 1838, 114 PP•

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McNaught, D. c. 1975. Zooplankton production in Lake Ontario as influenced by environmental perturbations. EPA-660/3-75-021. Ecol. Res. Series. Natl. Env. Res. Cntr. U.S. EPA.

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Dl

Rada, R. G. 1970. Distribution and abundance of zooplankton and phytoplankton in Biq Cend and Oahe Reservoirs of the Missouri River. M.S. Thesis, U. South Dakota. 90 pp.

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APPENDIX A

Temperature in OC at Sites I through Vin the Big Eau Pleine Reservoir, and at Site VJ.. below the Big Eau Pleine dam, during September, 1973 to September, 1974.

n P· n n n ~ r:-- n I"\ p R ~ ~ 'it- 'it. r:-- r:-- °' °' p r:-- r:-- n r:-- "" ~ ~ -!.. "' °' ~ ... ... °' ~ r:-- °' ~ °' r:-- ~ ~ ?.' ~ ... ... ~ ... ~ ... ... °' °' "' ~ 0 ~

... ... .... ;; ... - c.: N N

"' ... c.: .,; ... - -0 ~ ..: .; "' ... - .,; "' ~ ..; N N ... ... .... N ...

,.; ..; ..; ~

..; ..; ..; ..; .; .; .; .; .,; .,; .0 .,; k 0, 0, 0, ~ ~ ~ :, Q) .. Q) .,,

8 8 8 0 0 ol ol • ., ., .. z'! ..: Ill Ill Ill Ill :z: :z: :z: :z: ... ... la, la, la, .. Site I

1.0m 25,0 21.0 1J,5 16,0 8,5 J.O 1,0 1.0 1,0 1,0 0,0 1,0 2,5m

Site II

1.0m 25,5 19.0 1J,O 16.0 2,0 2,0 o.o 1,0 1,0 1,0 1,0 1,0 1,0 2,.5111 2.5.0 19,.5 12 • .5 1.5.0 2,0 o.o .-5,0111 I..

Site III

1,0m 2.5.0 19,.5 1:,.0 1.5,0 J.O 1,0 o.o 1,0 1,0 1.0 1,0 1,0 2,.5111 2.5.0 20.0 lJ,0 1.5.0 1,0 o.o .5,0m 22.0 14,0

Sih IV

1,0111 24.0 21,0 !J,.5 15,0 4,0 1,0 o.o 1, 0 1,0 1.0 1,0 2,5m 2J,5 21,0 1),.5 1 .5,0 1,0 0,0 J.O 5,0m 21.0 21,0 lJ,.5 15,0 1,0 o.o

Site V

1,0111 2:,.0 21,5 1.5.0 15. 0 10 • .5 4,0 2,0 0,0 2,0 1,0 1,0 1.0 1,0 2,5m 2J,O 21.0 15.0 15,0 10,.5 2.0 1,0 2,0 1,0 1,0 2,0 2.0 5,0111 22.0 21.0 15,0 15,0 10,5 2,0 o.o

10, Ota

Site VI

1. Otll 24,0 21,0 16,0 16,0 10,0 0,0 J,O J,5 1,0 2,.5111 2:,.5 20.5 15,5 15,0 9,5 J,O J,O 2,0 5,0m 2J,5 20,0 15,0 14,0 9,.5 J.O J,O J,O

APPEl-JDr.,<: A· continued

Temperatuz:e in °c at Sites I through Vin the Big Eau Pleine Reservoir, and at Site VI below the Big Fau Pleine dam, during September, 1973 to September, 1974.

it it ~ it it it F-- it it it ~ it "' f.. it it it it it ... "' ;!;' "' ;!;' ;!;' ;!;' "' "' ;!;' "' ... "' ;!;' "' °' ~· "' ... "' "' ... ... .,j ... ... ~· ... ... ... ... "" ... ·

"' .,j r.: "' ~ .,j r.: c-i .,j

"' fD ~ 0 "' ... N ~ ... ... N N ... ... ("'\

.c ... ... .; ~ .; ., ., ., ., ., ... ... ,i, .;, ,i,

~ ... ... ... 3 C C § § ~ ~ ~ l>t

l ~ ii! l i:! :, :, :, ~

:, ~

., -< .., ..., ..., ..., .., .., ..,

◄ ◄ Ill

Site I

1.0111 ?,O 11.0 18,0 19, 5 2J,5 25,0 22,5 26,5 21.0 2 • .s,,i ?,0 11.0 1?,5 18.o 20,0 25,0 21.5 23.5 20.5

Site II

1,0m 11,0 1?,0 20.0 2J,.5 25,0 21.5 2.5,.5 20 • .5 2,.5111 11,0 1?.0 20,0 22,0 25,0 22,0 24.0 20,0 5,0111 11,0 14,5 19 ,0 17,5 2J,0 21..5 2J.O 20,0

Site III

1,0111 8,0 11,0 16,0 20,0 2),.5 25.0 21.5 22,.5 18,5 2,5111 11.0 16.0 19,.5 ;;>0,.5 25,0 21..5 22.5 18,0 5,0m 11.0 14,5 19,0 17,.5 2J,.5 21..5 22.0 18,0

Site IT

I ,Om 6,5 11,0 16.5 19,.5 25,0 26,0 22.0 2J,O 21,.5 2.~m 6,5 11.0 15.5 19,5 22,0 25.0 22,0 2),0 21.5 5.om 6.0 11,0 15,0 19,0 18,.5 2'1.0 21 • .5 22,.5 21.0

Site V

1,0111 1,0 11,0 15 • .5 19,.5 22.0 22,0 26.0 2J.O 24,0 18,.5 2,.5111 1,0 11.0 15.5 19.0 20.5 22.0 25,0 22.0 24,0 19,0 5.0m 2,0 11,0 15,0 18,.5 18,0 21.0 24,0 22,0 2J,O 18,.5

10,0111 11.0 14,.5 18,0 1?,0 1?,.5 18,.5 21 • .5 21 • .5 18,0

Site VI

1,0111 J.O 12,0 18,0 19,.5 2L5 25.0 2J,O 24,0 21,.5 2.5 .. J.O 11.0 18.0 19.0 21.0 21~ • .5 22.0 2),5 21,.5 5,0m J,O 11.0 18.0 19,0 21,0 24,0 21.5 22,0 21,0

APPENDIX B

Dissolved oxygen in ppm, and percent saturation (in parentheses) at Sites I through Vin the Big Eau Pleine Reservoir, arrl at Site VI below the Big Eau Pleine dam, during August 31, 1973 through September 5, 1974.

Depth in M~era,

Date

Sit.a I

1.0 2 • .5

Aug, Jl, 197J 7,4

Sept, 7, l9?J

Sept, 20, l97J

Sept., 2), l97J

(.52)

12,0 (90)

10,0 (1)5)

Oct, 5, l97J 11.6 ( 116)

Oct, 21, 197) 10,8

Oct, 27, 197)

Hov, 16, 197J

Ho-,, 22, 197)

Dec. 1, 197)

(92)

2,0 (14)

Feb, 1, 19-;-. 7,7 (54)

Site ll 1,0 2 • .5 .5.0

4,4 2.6 (48) (Jl)

6.9 6,6 (66} (61)

8.J 7,8 (84} (77)

8.9 8,9 (64} (64}

12.5 12,J (85} (84}

0, 1 (0, 7)

7,1 (50)

Site III Site IV Site V

1.0 2,.5 .5.0 1.0 2 • .5 .5.0 1,0 2,.5 5,0 10,0

5.4 ),4 (.59) ()6)

7,2 4,6 ),0 (81) (.52) ()4)

9,4 7,0 4,5 (106) (79) (.50}

9°,6 7,8 6,9 (9.5) (77) (69)

9,5 B.9 9,2 8,7 8,9 (90) (85) (88) (BJ) (86)

8,4 7,8 7,J 8.2 7,7 7,0 8,2 7,8 7,4 (BJ) (77) (71} (81) (76) (?O) (81) (77) (-;-.)

8,7 8.4 (61) (.58)

12,0 11,2 (82) (76)

1.8 ( 1))

),8 (27)

8.2 8.0 7,8 (,..) (72) (70)

(~~J 8,1 7,9 8.6 8.6 8.6 J<') (57) (55) {62) (62) (62)

11,4 11,2 10,4 12.~ 12.2 11,9 (78) (76) (71) (85) (84) (80}

8,6 6.2 (60) (46)

7,8 6.4 (56) (46)

1.5 2,0 ( 11} ( 14)

2.6 (29)

4,5 (4.5}

Site VI 1.0 2,.5 5,0

11.5 10.5 10,0 {1J7) (124) (118)

15.2 12.2 10,0 (168) (1J6) (110)

9,$ 9,J 0.5 (96) (93) (84}

8,J 6.9 J.6 (84) (69) (J5)

8. 7 7,6 7,2 (77) (67) (6J)

9,9 9,7 9,7 (-;-.) (72) (72)

a u

APPENDIX B continued

Dissolved oxygen in ppm, and percent saturation (in parentheses) at Sites I through V in the Big Eau Pleine Reservoir, and at Site VI below the Big Eau Pleine dam, during August 31, 1973 through' September S,'1974.

Depth Site I Site II Site III Site IV Site V Site VI in meters: 1.0 2.5 1.0 2.5 5.0 1.0 2.5 5.0 1.0 2.5 5.0 1.0 2.5 5.0 10.0 1.0 2.5 5.0

Date

Feb. a, 1974 6.5 4.9 2.9 3.7 2.0 0.7 (46) (34) (20) (26) (14) (4.9)

Feb. 15, 1974 5.7 3.4 2.9 0.8 0.9 0.4 2.3 2.2 2.0 (40) (24) (20) (5.6) (6.3) (2.8) (16) (16) (15)

Feb. 22, 1974 5.5 3.3 (38) (23)

Mar. 2, 1974 6.0 3.8 2.5 1.3 0.5 0.3 (42) (27) {17) (9.1) (3.5) (2.1)

Mar. 16, 1974 9.5 8.3 8.2 (71) (61) (61)

Apr. 13, 1974 10.3 10.2 (87) (86)

Apr. 21, 1974 10.8 9.2 9.2 9.0 7.7 7.0 7.7 (94) (77) (77) (73) (54) (50) (55)

May 13, 1974 9.5 9.3 9.2 9.3 9.0 (87) (81) (83) (84) (82)

May 16, 1974 9.5 9. i 9 .1 8.5 8.7 8.5 8.5 8 .1 8.1 7.9 6.0 5.8 (86) (83) (83) (78) (79) (78) (77) (74) (74) (72) (56) (53)

May 28, 1974 7 .0 6. 7 9.0 7.4 6.9 8.5 8,5 6.7 8.7 7.9 7.5 8.4 8.5 8.0 6.4 (74) (70) (93) (77) (68) (86) (86) (66) (89) (79) (75) (84) (85) (80) (63)

June 7, 1974 7.9 7.9 8.0 (84) (84) (85)

June 13, 1974 6.9 6.3 9.1 9. 3 7. l 9.7 9.3 8.2 9.7 9.4 7.8 (76) (67) (100) (102) (77) (107) (102) (88) (106) (102) (85)

June 14, 1974 · 8.2 8.0 7.5 7.0 9.0 8.i 8.7 (90) (87) (80) (74) (98) (94) (94)

APPENDIX B continued

Dissolved oxygen in ppm, and percent saturation (in parentheses) at Sites I through Vin the Big Eau Pleine Reservoir, and at Site VI below the Big Eau Pleine dam, during August 31, 1973 through September, 1974.

Depth Site I Site II Site Ill Site IV Site V Site VI

1n meters: 1.0 2.5 1.0 2.5 5.0 1.0 2.5 5.0 1.0 2.5 5.0 1.0 2.5 5.0 10.0 1.0 2.5 5.0

Date

June 26, 1974 9.9 5.0 14.2 13.3 3.0 15.6 11.0 4.6 18.1 13.7 6.5 (117) (55) (167) ( 152) ( 33) (183) (125) (48) (215) (157) (70)

June 27, 1974 12.8 10. l 7 .o 4.2 (14.1) (112) (74) (44)

July 2, 1974 8.2 8.2 7.5 2.4 7.7 7 .8 7.6 (94) (94) (84) (25) (87) (88) (85)

July 16, 1974 6.7 4.1 8.0 7.8 2.2 9.0 7.9 3. I 10.6 7 .8 4.5 9.3 8.3 5.4 0.2 8.3 7.4 (82) (50) (97) (95) (26) (!OB) {96) (37) ( 132) ( 94) (53) (114) (101) (64) (2.2) (101) (89)

Aug. 5, 1974 7.8 6.7 7.1 6.6 6.6 5.9 5.7 5.5 6.4 6.5 6.0 7.0 5.3 4.7 5. l (90) (76) (81) (76) (75) (67) (65) (63) (74) (75) (68) (82) (61) ( 54) (58)

Aug. 8, 1974 5.0 3 .8 1.3 (59) (44) (15)

Aug. 19, 1974 8.9 4.7 12.1 5.3 2. l 5.5 4.9 2.7 8.4 7.5 3.9 11.0 10.0 6.5 0.3 7.4 7,3 2.6 (110) (55) (148) (63) (24) (64) (57) (31) (98) (88) (45) (131) (119) {77) (3.3) (88) (86) (30)

Aug. 30, 1974 6.5 5.7 6.5 7.0 6.1 5.6 5.0 4.9 (74) (64) (73) (77) (67) (64) (57) (55)

Sept. 1, 1974 9.2 9.0 7.9 7.7 1.7 6. l 5.4 8.8 8.7 8.3 (98) (95) (84) (82) (83) (65) (57) (100) (99) (93)

,..,.

APPENDIX C

Secchi disk readings in meters at Sites I throug.l-i V in the Big Eau Pleine Reservoir, and at Site VI below the Big Eau Pleine dam, during August 31., 1973 through September 5., 1974,

"" "" "" "" .., ,.._ ,.._

"" "" .., "" "" ... .. .,. ... ,.._ ,.._ ..... OI 0, "" .... ,.._

"" .... .... ..... "" ,.._ ..... .,. ... ..... .... ...

OI OI OI - - ..... 0, OI ..... OI OI OI .... OI OI ..... ..... ... OI .... - - - OI - - OI - - - OI - - 0, OI - - OI

0 . - - - - - -. . ..: .., . . .

ID• ..: . ~

. ..: - - N N . - .... .; - . a, .; "' ..: .., "' N N - - N - - N N

,;. ..; .; ..; ..; ..; ..; ..; > > > > .a .0 .0 .0 ..: Q. a. C. C. u C: . C: ::, ., ., ., ., 8 8 .g 0 0 0 0 ., ., ., ., ., ., .,

"' < V'I VI V'I V'I z: z: z: z: 0 .., .., .... .... .... .... E

Site I 0.61. 0.53 0.38 0.53 0.84 0.64 0.69 0.76 0.69 0.76 0.69 0.76

Site II 0.23 0.23 0.15 0.15 0.30 0.30 0.46 0.38 0.30 0.30 0,30 0,30 0.38

Site III 0.23 0.30 0.30 0.23 0.38 0.38 0.30 0.61 0.15 0.15 0,15 0,15

Site IV 0.46 0.30 0.30 0.30 0.38 0.30 0.34 0.68 0,15 0.23 0,23

Site V 0,53 0,46 0.46 0,46 0.53 0,46 0.68 0,61 0.68 0.68 0,30

Site VI 0.46 0.53 0.46 0.61 0.68 0.61 0.46 0,68 0.76

.,. .... .. ... .... .,. ... ... ... ... ... ..... ..... ..... .... ... ... ... ,.._ ..... ,.._ ,.._ ... ..... ... ... ,.._ ..... .... OI OI OI ,.._ ,.._ ,.._ ,.._

"' "' "' "' ..... OI ..... ,.._ OI OI OI - ~ OI "' "' .... .... .... "' - "' OI - .... -- -..,· . . . . .... · .; .; o• . "' - ..; .; . . ..., ... "' ._; ~

. -- N 00 .... - N N - GD - .., N ..; ..: ..: ..: ., ., ., ., ., >, >, .;. ti. ti. .;, >, >, >, C: C C: C: C: '; Q.

l Q. Q. l ~ "' :, ::, :::, :, :::, :::, :::, :::, ~

:::, ., < < ::,; -, -, -, .., .., .., .., < < < .,,

Site I 0.38 0.99 1.22 0.64 1.00 0.55 0.40 0,23 0.12

Sf te II 0.84 l,g() 0.55 0.61 0.46 0.24 0.23 0.18

Site I II 0.82 1.07 1.98 1.28 0,58 0.61 0.43 0.40 0.30

s1te rv 0.76 0.88 2.13 1.22 0.27 0.49 0.49 0.40 0.26

Site V 0,68 1.90 0.98 0,73 0.53 0.58 0.18 0.43

Site VI 0,46 0.79 2.21 1.07 0.79 0.55 0.73 0,73 0.34

APPENDIX D

Table I: Monthly mean number per liter (#10 oblique Clarke Bumpus) of zooplankton at Site I in the Bit:; Fau Pleine Reservoir.

NWlber of Total

~ .llwlu- Lepto- Calan- Cyclo- !lotl- Eph1- O■tra- Date■ of ~ Daphnla daphnia osoma ~ Me.crothr1x Leyd1g1a Chydoru11 ~ ill!_ Naupl11 ~ !.!!'!.. p1ala ~ ~ ~

Sept,, 197.) o.oo 0,10 0,96 o.6:, 0,00 0.:,2 0,?l o.oo 0.00 0,18 0.Jl 7,16 0.00 0,00 2 10.:,9

Oct.., 197.) o.oo 0,00 o.oo 0,06 o.oo 0.00 8,}7 o.oo o.oo o.oo o.06 0,?0 o.oo o.ao l l,J9

Nov,, 197.) o.oo o.oo 0.00 0,12 0,00 0.02 0,48 0,00 0,00 0,06 0,04 0,19 0,00 0,00 l 0,91

I,ec., 197J Not Sa111pled

Jan,, 19?(1. Not S&l'lpled

f.!'h,. 19;4 Not Sa111pled

i-'.ar,, 19?(1. Not S1u11pled

Apr,, 19?(1. 0,00 o.oo o.oo 0,00 Trace o.oo 0,02 0,00 Trace 0,00 0,0) 0,12 0,00 0,00 l 0.16

Z.:h.:J, 19,-. 11.c;5 1.14 0,06 eo,20 0,00 0,00 0,62 0,00 0,00 6,60 21.9:, 11,10 0,00 0,00 2 1J9,l!0

June, 19?(1. 20.00 J,12 0,66 107,21 0,00 O,JO 0,72 1.01 0,16 5,10 8.20 7,04 . 0,00 0,26 2 1.5), 78

July, 19?(1. 78. 7.l 0,9J 51.95 J,49 0,00 o.oo 4,19 0,70 4,4J 28.65 5J,5B 6,29 o.oo o.oo 1 2)2,94

AU(,, 19?(1. 79,65 22,70 4),56 66,9) o.oo 0,00 109,96 0,00 16,4J 46,56 62,29 98,28 o.oo 0,00 ) ~6.)6

Sept,, 19?(1. ?lot Supled

Hun 24,,i. ),50 12.15 )2,J) 0.00 o.oe 14,66 0.21 2.6) 10,92 16.)0 16,)6 o.oo o.o:, 135.n

APPENDIX D continued

Table II: Monthly mean number per liter (#10 oblique Clarke Bumpus) of zooplankton at Site II in the 3i,:s Eau Pleine Reservoir.

Humber or Total

Cerio- Dlephan- Lepto- Calan- Cyclo- Rot1- Ephi- 0etra- Datee of ~ Daphnia da(?hnla osoma ~ Macrothr1x Le.J:d15la Chydorua ~ ~ llaupl11 polda ~ piale £2!!!_ Ave'd ~

Sept,, 19?J 61.8) 12.JJ 45,?0 55,60 0,00 0,22 220.22 0.24 10.97 21.64 29,.5 0,70 o.oo 0,00 2 45f,95

Oct., 197.) 20,'9 7.68 6.76 59,61 o.oo o.oo 142.26 o.oo l.5,67 9;e:, 41,48 J.:,8 o.oo o.oo l )07.26

llov,, 197'.l 6,12 0,41 0,26 J6,J6 0,00 0,00 1.5.02 0,00 21,88 5,5) 29,88 22,22 0,00 0,00 2 lJ?.68

Dec,, 197.) l,21 o.oo 0,00 6,82 0.19 0,00 2,62 0,00 4.67 8,87 lJ,26 S.5,67 o.oo 0,00 l 9),41

Jan,, 197'1 !'lot SMpled ,.__

F.tb,, 1974 Not Salllpled C

~!11.r., 19~ Not Sa.'nrled

Apr,, 19~ Not Sllr.pled

t'.ay, 19?11 ?.9,25 0,26 0,41 6,02 0,00 0,00 0,94 0,00 o.68 )6.84 60,92 201.22 0,00 0.20 2 JJ6, ';i>

June, 19-;i> J9,84 2,119 0,4) 1),72 0,00 0,00 8,)4 0.Jl J,24 6,04 16.12 )2,08 0,00 0,00 2 122.61

July, 19?11 11.9 0,10 16, 56 .5,J8 o.oo 0,00 2,48 O,Jl 10,76 24,11 J0,42 1,45 o.oo o.oo l lOJ,48

Aug,, 19?11 26,Jll 0,87 47,26 Y•,27 o.oo 0,00 ?0,22 0,14 17,22 )). ?II )7,78 1.)8 0,00 o.oo 2 269,26

Sept,, 19?11 Not Sampled

l!ean 24.64 J,02 14.67 27,22 0.02 O,OJ .57,76 0.12 10.64 18.)2 J2.42 J9,76 o.oo 0.02 228,62

APPENDIX D continued

Table ITT• ~.J..• Y!onthly mean number per liter (#10 oblique Clarke Bumpus) of zooplankton at Site III in the Big Eau Pleine Reservoir.

lh191'ber of Tot.al

Cerio- tlaphllll- Lepto- Calan- Cyclo- ftoti- Eph1- o.tra- Dat•• of ~ Darhn1a ~ O,:jOntl .!!2!!!.!!! Hacrothrlx Lezd1j!l1a Chtdorue ~ .2!!!!,_ Naunl11 po1da !.!!!'.... .2l!l! ~ ~ 1-:eanp

Sept., 197.l 46. 51. 4.49 )8.82 74.96 o.oo o.oo 21?.6? 0.15 10,76 14,?J l?,22 ),81 0,00 0,00 ) 4)1,lS

Cct., 197.l )1,66 5,05 12.80 88,57 0,00 0,00 1)4.0) 0,00 21,22 1.5,8) 26,94 0,67 0,00 o.oo 1 ))6,76

::ov., 197.l 7,89 0,44 0,48 12,44 0,00 0,0.5 )0.5() 0,00 14.26 1,.55 12,.52 19.19 0,10 0,00 2 99,42

Dec., 197.l 2,.55 0,00 0,00 ),72 0,00 0,00 1,44 0,00 7,28 0, 71+ 4, 7.l 10,29 0,00 0,00 l )0,7.l

Jan.• !9'i4 !lot Sa111pled ...J

Feb., 1971+ Not Sampled ~

~·ar., 19'i4 Not S&111pled

Apr,, 19'i4 Not Salliplod

l".ay, 19'i4 45,)2 0,2) 0,00 2,94 0,00 0,00 0,58 0,00 0,96 )1,26 94,54 82,8) 0,00 0,00 2 258,66

.:rune, 1974 44,60 0,46 0,21 12,80 0,00 0,00 9,60 0,50 1),11 6, .52 9,78 11.14 0.06 0,00 2 10?,?8

July, 19~• 21.81 0,08 4,48 2.52 o.oo 0,00 l,?l 0,90 11,48 14,65 2),44 0,24 o,oo o.oo 1 81.)9

Aug., 1974 26.eo o,co 46,62 49.78 o.oo 0,00 l?.89 0,24 16,68 42.44 29.94 0,)4 0,00 0,00 2 2)0,7.l

Sept,, 1971+ 16,9) 0,00 47,85 81,05 0,00 0,00 10),18 o,oo 10,71+ )7,76 6,18 21,81 o.oo 0,00 .. 1 :,25,50

Heu 27,12 1,19 16,81 )6,5) 0,00 0,00 S?,40 0,15 11,8:, 18,)9 25,25 16,?0 0,02 0,00 211,)9

APPENDIX D continued.

'l'able r1: :;lonthly mean nwnber per liter (#10 oblique Clarke Bumpus) of zooplankton at Site IV in the Big Eau Pleine Re;;ervoir.

Nua'ber or Total

Cerio- ~- Lepto- Calan- Cyclo- Rott- Eph1- O•tra- Datea or ~ Daphn1a d~t•ilrnta OtiO'"~l ~ Macrothrix IMX:d115la Ch;xdorue ~ .!!.!.!!_a_ NauplU poida !!!!.. piala ~ ~ ~

Se'l)t,, 197:, J2,71 2.46 J,5.48 .5J,2? 0,00 0,00 lJB,01 0,1? 10,89 12,4? 11,?0 ),96 0,00 0,00 ) :,01,02

Cc-t. 1 197:, 21,20 2.12 11,0J 18.24 0,00 0,00 1:,0.20 0,00 ?,6) 11,24 9,:fo 1,06 0.21 0,00 1 212.0.5

::ov. I l97J 8,96 O,JJ 0,16 18,88 0,00 0,06 14,14 0,00 10,84 O,J6 .5,90 8,.59 o.oo 0,00 2 68,22

Dec,, 197:, 4,01 0,00 0,00 .5,?6 0,00 0,00 1.82 0,00 ?,)) 0,62 ),94 12,99 0,00 o.oo 1 :,6,48

Jan.' 1974 Not S,unpled ...J

F.et., !974 Not Sa,11:,led "' ~-:.a.r •• 1974 Not Sampled

Arr,, 1974 Sot Supled

~'.ay, !974 67,94 0,2.S o.oo 2,48 o.oo 0,00 0,00 0,00 1.24 )0,2.S 106,61 )9,1? 0,00 0,2.S 1 247,94

June, 1974 J9,02 0,18 0,18 2,40 0,06 0,00 7,20 0,5J 16,94 4,20 9,28 12,50 0,04 0,00 2 92,.S)

:~11. 19';'> 20, 71 0,00 l,JIJ O,J6 0,00 0,00 0,29 0,114 21..51 17,44 9,4.S 1.09 o.oo 0,00 1 72,68

Aul,, 19-:X. 2J,6.5 0,05 24.J2 1.5,22 0,00 0,00 20,J.5 0,21 111,04 J6,8J 26,20 1,6? 0,00 0,00 J 162,:fo

se,.t .• 1974 Not Slllllpled

:~ean 2?,28 o.6? 9,07 14,,58 0,01 0.01 )9,00 0,17 11.:,0 14,18 22,8) 10,lJ 0,0) 0,0) 1119,29

APPENDIX D continued

~able V: r~onthly mean number per liter (#10 oblique Clarke Bumpus) of zooplankton at Site Vin the Big Eau Pleine Reservoir.

lf1111ber or Total

Cerio- ~- Lepto- Cal.an- Cyclo- RoU- Ephi- Oatra- DatH ot ~ Daphn1a ~ OSO!'la ~ Macrothr1x Lo;tdle.;1a Ch:tdoru■ ~ ~ Naupl11 po1da ~ piala ~ ~ •;-,

Sept., 197) 25.40 0.50 y,,?O 12,0J 0,00 0,00 1.57.49 O,JJ ?,7) 8,69 7.9.5 4,20 0,00 0,00 ' 2'9,02

Oct., l97J 9.42 1.02 B,98 7,88 0,00 0,00 172,)2 o.oe 4,76 5,87 lJ,68 0,47 0,14 0,00 2 224,62

~iov,, 197J 7,12 0,24 0,41-f 11,0J 0,00 0,08 19,)4 0,00 6,78 2,77 8,66 4,Jlt 0,18 0,00 2 60.98

tee., l'?7J J,99 0,00 0,00 10.1n 0,00 0,00 2.19 0,00 6,6.5 0,4J .5,7.5 9.6J 0,04 o.oo 1 )9.14

Jan., !9',X;. Not SUIJlled ---l

Fe~., !9?1+ !lot Sa111pled w

t:ar., 19?1+ Not Supled

Apr., 191♦ 0.04 0.00 0,00 0,00 0,00 · 0,00 0,00 0,00 0,00 0,14 0,87 0,91 0,00 0,00 l 1,96

~'.ay, 19-;'tl, 47,lJ 0,18 0,00 0,00 0,00 0,00 0,18 0,00 1,79 6,09 118,4,5 .5,JB o.oo 0,00 1 179,20

.. 'u.nc 1 1974 22,0J 0,00 0,00 0,82 0,00 0,00 0,.57 0,08 lJ,79 lJ,87 28,6,5 l,6J 0,00 o.oo 1 81.61

Ju!y, 19'11+ 2El,J9 0,00 0,09 0,22 0,00 0,00 4,10 0,66 24,)2 6,72 6,47 24,20 0.00 o.oo 2 9.5,17

Aug,, 1974 Jl,64 0,00 21.,,0 7,82 0,00 0,00 2.86 0,24 2.5,21 2.5,88 2.5,82 0,47 0,00 0,00 2 141.)lt

Sept., 1974 41.71 0,00 19,JO )9,09 o.oo 0,00 44,09 0,71 26,4.5 21,9) 4,77 40,04 o.24 0,00 l z,e.:n

~~ean 21,69 0,19 8,49 e.9:, 0,00 0,01 40,Jl 0,21 ll,7.5 9,24 22,11 9,lJ 0,06 0.00 1)2,12

APPENDIX D cont:mued

Table VI: Monthly mean number per liter (#10 oblique Clarke Bumpus) of zooplankton at Site VI below the Big Eau Pleine dam.

N11111ter or Total

Cerio- D11tphan- Lapto- Calan- Cyclo- Rot1- Ephl- Oetra- Dat.ee ot ~ ~ eur~~.la OSOPl:i\ ~ llacrothr1x Loxdlf1& Chxdorua !!2!:!!.._ ~ Naupl11 i!!.lli.. m!.. piala £.2!!!._ ~ l!eane

Sept., l97J 6,61 l.08 21,48 19,88 0,00 0,10 86.JO 0,00 '6,04 6,12 12.08 21.)8 o.oo 0,00 2 18).,58

Oct., l97J 2.46 0,62 J,)8 76,20 o.oo 0,00 5J,90 0,00 J,10 4,44 12,92 20,88 o.oo 0,00 2 177,90

~ov. r 197J 2.)8 0,05 0,00 J6,J8 0,00 o.oo 2.62 0,00 J,)8 0,8.5 :,.;ii. 18.44 o.42 o.oo 2 68,26

Dec., 1973 !lot Surled

J&tl, • 1974 Not Sa.mpled ... ,j:

fe't., 19-ic. Not Sampled

~:a.r.' 1974 Not Sampled

Apr., 1974 llot SaMpled

~'.ay, :!.9'."+ !lot Sa.mpled

Jun~, l','74 21,82 O,Jl 0,00 lJ,JS o.oo 0,00 0,00 0,00 0,61 4,89 ,58,00 2,96 0,00 0,00 1 101,94

Ju!y, 19~. 21.44 0,00 0,11 0,08 o.oo 0,00 4,J.5 0,16 16,48 9,70 5,2) 22,04 o.oo 0,00 .2 79,Y/

Aug., 1974 12.64 o.67 .. 8,82 49,66 o.oo o.oo 1.70 0,00 7,90 20,64 1.5,24 10.12 o.oo o.oo 2 127,99

Sept., 1974 )4,18 0,00 8,64 70,.52 0,00 0,00 100,0J 0,00 21,.59 29,87 7,!,6 87,44 0,00 0,00 l JY,.82

~.ean 14,79 0,)9 6,06 )8,01 0,00 0,01 J.5, !,6 0,02 8,44 11,02 16,40 26,27 0,06 0,00 1.57,0)

APPENDIX E

Table I: Monthly mean number per liter (#10 Van Dorn) of' zooplankton at Site I in the Big Eau Pleine Reservoir.

N1111'ber tepth or Total

1n Cerio- D1aphan- Lepto- Cala.n- Cyclo- RoU- Sph1- Oetn- Datee or !:onth ?ctera I'aphr.1a ~ osoma !2!!!.!!! tiacrothr1x Leyd1tia Chydorus ~ ~ Naupl11 poida !!a p1al1 .w!!._ ~ !!!!!.!

Sept., 197'.l 1,0 0,25 0.25 1,.5 1 • .5 0,00 0,25 2,2.5 0,00 0,00 0,12 1,00 7,'!J) 0,00 0,00 2 14,62

l'ean 0,25 0.2.5 1.5 1,5 0,00 0,25 2,25 0,00 0,00 0,12 l,00 7,'!/) 0,00 0,00 14,62

Cct,, 197'.l 1.0 0,75 o.oo 0,62 6,88 0,00 O.J8 5,25 0,00 0,)8 0,5 J,12 2,)8 0,00 0,00 2 20,26 l•:ean 0,75 0,00 0,62 6,88 0,00 0,'.)8 5,25 0,00 0,)8 0,5 J,12 2,)8 0,00 0,00 20,26

Sov,, 1973 1.0 0,00 o.oo 0,00 1.00 0,25 0.50 J . .50 0,00 0,00 o.oo 0,25 0,00 0,25 0,00 1 5,75 t;ean 0,00 o.oo o.oo 1.00 0,25 0,.50 J,.50 o.oo o.oo o.oo 0,25 o.oo 0,25 0,00 5,75

-..J !.ec., 1973 :;ot Sa.r.iplec! lT1

J'an. I 19'}1; 1.0 o.oo 0,00 o.oo 0,,50 0,00 0,00 0,25 0,00 0,00 0,00 0,75 0,,50 0,00 0,00 l 2,0 l'ean o.oo o.oo o.oo 0 • .50 0,00 0,00 0,25 o.oo 0,00 o.oo 0,75 0,,50 o.oo 0,00 2,0

Fet,, 19~ 1.0 o.oo o.oo 0,00 0.19 0,00 0,00 0,25 o.oo 0,06 o.oo 1,06 0,12 0,00 0,00 4 1.68 Henn 0.00 o.oo 0,00 0,19 0,00 o.oo 0,25 0,00 0,06 0,00 1,06 0,12· o.oo 0,00 1.68

:·:er., 19'}1; 1.0 0,00 o.oo o.oo o.oo 0,00 o.oo 0.50 0,00 0,00 0,00 0,75 0,00 0,00 o.oo l 1.25 ~ea.n o.oo 0,00 0,(10 0.00 o.oo 0,00 0. 50 o.oo 0,00 o.oo 0,7.5 o.oo 0,00 o.oo 1,25

A;r, 1 19-;,t.. 1.0 o.oo o.oo o.oo o.oo 0,00 0,0!) 0,00 o.oo 0,00 0 • .50 0,75 0,00 0,00 o.oo 1 1,25 2 • .5 0,00 o.oo o.oo 0,00 0,00 0,25 0,00 0,00 o.oo 0.06 0.25 . 0,00 o.oo 0,00 l 0,50

l'ea.'\ o.oo 0,00 o.oo 0,00 o.oo 0,17. 0,00 0,00 0,00 0,25 0,,50 0,00 0,00 o.oo 0,!I?

''.ay, 19'}1; 1.0 100.12 1.62 o.oo 129. 75 0,00 0,00 o.oo 0,00 0,00 2.12 20,J!! 9,88 0,00 0,00 2 26::,,e1 2.5 :>6.r.'1 2.25 0.12 1,0,flll 0,00 0,12 1.25 o.oo 0,00 1.62 20,62 7,88 0,00 0,00 2 101,62

~:ean 63.50 l.94 0,06 135,)2 o.oo 0,06 0,62 o.oo 0,00 1,87 20,'!/) 8,88 0,00 0,00 1e2.15

June, 19'}1; 1.0 44,6?. 0,62 o.oo 150.00 0,00 0.12 0.62 1,12 0,12 1.)8 11.88 9.;,5 o.oo 0,25 2 219,Q8 2.5 2l.J8 J,12 0.12 57,75 0.25 0,25 1.12 0,00 0 • .50 1,62 lJ,88 6.88 o.oo 0,00 2 106,8?

:-:ean JJ,00 1.87 0.06 lOJ,88 0.12 0.18 0,87 0.56 0,Jl l, .50 12.88 8,06 0,00 0,12 16J,41

APPENDIX E continued

':'able I (continued) : f•1onthly mean number per liter (#10 Van Dom) of zooplankton at Site I in the Big Eau Pleine Reservoir.

ll1111lier Depth or Total

in Cerio- !li~phM- Lcpto- Calan- Cyclo- Rot1- Eph1- Oetra- Date■ of ~ ~ ~ ~ o:.1orn:i .!!2.!.!!!!! Macrothrix Le;id151a Ch;xdoru■ ~ ~ ffauplH ~ !!a p1ab ~ ~ !:!!.!!!

July, 1974 1,0 121,00 1.75 n.25 5,00 0,00 0,00 4, .50 o.oo 7,.50 28,00 72,25 27,25 o.oo o.oo l :,+o • .50 2.5 ?'3,25 0,75 JJ,50 1,75 0,00 0,00 1,75 0,25 5,?5 19,50 J6.00 21.00 o.oo o.oo 1 198,50

~'.ean 99,6;:> 1.25 5J,J8 J,J8 0,00 0,00 J,12 0,12 6,62 2J,75 91,12 24,12 o.oo o.oo 269,4S

Aue., 1974 1,0 71.6? 24,08 )8,17 121,08 0,00 0,00 1J8,08 0,00 lJ.JJ JJ,92 74,08 1J6,08 0,00 0,00 ) 650,49 2.5 J6,8J 9,50 10,75 15,92 0,00 0,00 J05,50 0,00 9,JJ J0,8J 62. 50 J9,50 0,00 o.oo J ,520,66

~:ean 51,25 16,?9 24,46 68.50 0,00 0,00 221,?9 0,00 11,JJ J2.J8 68,29 87,?9 0,00 0,00 585, 58

Sert,, 1974 !lot Sa.'llpled '3 en

~:ea.n 1.0 J0,76 2,57 10.J2 )7.81 0,02 0,11 14.11 0,10 1,94 6,05 16,9) 17,54 0.02 0,02 11 109,29 Mean 22,65 2.01 7.26 24,65 O,OJ 0,14 21,67 0,06 1,70 5,49 14,84 12.67 0,02 0,01 11 llJ,42

APPEi"1DIX E continued

~able II: :l!onthly mean number per liter (#10 Van Dorn) of zooplankton at Site II of the Big Eau Pleine Reservoir.

lh1•t.er !>tooth or Total

1n Cerio- Dil\Fhan- ~pto- Calan- Cyclo- Roti- Ephl- 0atra- DatH of ~ ~ .. tert1 ~ d~rhn1a ~-~ Macrothr1x Le;r:d!t:1a Ch.i:dorua ~ ~ llauplU polda !!a ptala £2.!!L ~ ~

Se:;,t., 1973 1.0 55,25 19.12 ,56.oo 69,J8 0,00 0,00 281,12 O,bO lB,25 14.12 :,4,75 0,88 (1.12 0,00 2 ,51<!!,99 2.5 52,00 22,JS 49,12 )5,62 o.oo 0,00 281.2.5 0,12 1.5,12 15,12 211,2.5 1. 7.5 0,12 0,00 2 496,!l.5

Mean 5J,62 20,75 .5,.56 52.50 0,00 o.oo 281. 18 0,06 16.68 14,62 29 • .50 l.Jl 0.12 0,00 522,90

Cct,, 197) 1.0 411,75 10.25 8,75 125,00 0,00 0,00 162,?5 0,00 Jl.75 12, ,50 48,25 J, .50 0,00 0,00 1 447,00 2.5 2).25 9,?5 6.00 117,00 o.oo 0,00 l?J,25 o.oo 15,00 10,75 21.?5 0,75 0,00 0,00 1 JCl?,50

Mean J4,00 10.00 7,J8 86.00 0,00 0.'JO 167,?5 o.oo 2J.J8 11,62 :,5,00 2.12 o.oo o.oo :,n.25

!;;iy,, 197J 1.0 J,25 o.oo 0,00 55,75 0,00 o.oo 1,.25 0,00 12.00 .1. 75 1.5,.50 14,00 0,00 o.oo 1 106, .50 -..J 2. '.i 2.00 0,00 0,00 111.25 o.oo O,IJO 4.~5 0,00 A, 50 1.25 10 • .50 12.25 o.oo 0,00 1 !iJ,00 -..J

Mean 2.62 0,00 o.oo J5,00 o.oo o.oo 4,25 o.oo 10.25 1,.50 1),00 lJ,12 o,oo 0,00 79,.,.

Dec., 1973 1,0 J.00 o.oo o.oo 15.25 o.oo o.oo 1,00 0,00 6.00 5,00 17,75 27,50 0,00 0,00 l 75,70 ?,5 2.25 0,00 o.oo 11.50 .o.oo o.oo 2.50 0,00 4,75 1.25 18,75 27-75 0,25 0,00 1 69,00

t'.ean 2.62 o.oo 0,00 l),J8 o.oo o.oo 1.75 o.oo .5,J8 J.12 18,25 2?,62 0.12 0,00 72,24

.!a.n., 197 .. 1.0 o.oo 0,00 o.oo 0,00 o.oo 0,00 0,00 o.oo 0,00 o.oo 1.00 1.00 0,00 0,00 1 2.00

t•ean 0,00 o.oo o.oo 0,00 0,00 0,00 o.oo o.oo 0,00 o.oo 1.00 1.00 0,00 0,00 2,00

l"o:,b, • 1971• 1.0 0,06 0,00 o.oo 0.12 o.oo O·,OO 0,06 o.oo o.oo o.oo 1 • .56 O,Jl 0,12 0,00 4 2.2)

Hean n.06 o.oo 0,00 0,12 o.oo o.oo 0,06 o.oo 0,00 o.oo 1,.56 O,Jl 0,12 o.oo 2.2)

!-:ar., 1974 1.0 0,00 0,00 0,00 0,25 0,00 o.oo 0,25 0,00 0,00 o.oo 0.75 0.25 0,,50 o.oo 1 2,00

?~ean 0,00 o.oo 0,00 0,2.5 0,00 0,00 0.25 0,00 0,00 0,00 0,75 0.2.5 0,,50 0,00 2.00

Arr., 197'- !10t Sampled

:·.ay, 197'- 1,0 ,50,J8 1.ee o.oo 16.?5 0,00 0,)8 0,75 o.oo 1,88 5,50 1JJ.J8 2)).88 o.oo 0,00 2 444,78 2,5 29,62 0,75 0,12 ?,)8 o.oo 0.12 0,62 o.oo 1,00 15.50 125.88 211, ,50 0,00 0,00 2 )92.49 5,0 25, 50 0,75 0.12 7,00 0,00 o.oo 0.50 o.oo 0,12 16.J8 52,62 172.25 o.oo 0,00 2 :'?5,24

f·'.ean J5,17 l.lJ 0,08 10,JB 0,00 0,17 0.62 0,00 1,00 12.46 10:,.96 205,88 0,00 0,00 J?0.8.5

APPENDIX E continued

Table II (continued) : Monthly mean number per liter (#10 Van Dom) of zooplankton at Site II of the Big Eau Pleine Reservoir.

N1&11ber Depth of Total in Cerio- Diaphan- Lepto- Calan- Cyclo- Rot1- Eph1- Oatra- DatH of

~ ~ ~ d,,i;hr.ia osoma .l!2.!!!!!! Kacrothrlx Lald1~1a Chxdorue ~ .2l!!!L_ KAurlH po1da !.!£!.. pida ~ ~ ~

June, 19?4 1,0 92.~e J,Jll 0,7.5 24,25 0,00 0,00 16,62 0,25 4,7.5 6,?..5 27,2.5 68,.50 0,00 o.oo 2 2'14,J8 2,.5 J9,75 1.50 0,12 17,7.5 0,00 o. J 2 19,75 0,2.5 2,75 7,12 21,12 47,12 0,00 o.oo 2 156,)5 .5,0 6,2.5 9,50 0,00 6,7.5 0,00 0,00 1.88 0,00 2.12 8,)8 16.00 J,J8 0,00 0,00 2 ,54,26

Mean 4.5, 79 4,79 0,29 16.2.5 0,00 0, 04 12, 75 0,17 J,21 7,2.5 21,46 )9,76 0,00 0,00 1.51,67

July, 19?4 1,0 l.5,2.5 0,2.5 19,7.5 ?,?.5 0,00 0,00 5,25 0,00 10, 50 20, 7.5 )9,2.5 10,50 0,00 0,00 1 129,2.5 2,.5 11.00 o.oo 12.25 9,7.5 0,00 0,00 5, 50 0,2.5 10,7.5 1.5,00 14,00 2,75 0,00 0,00 l 81.2.5 -..J 5,0 fl,2.5 4,.50 l.00 0,00 0,00 0,00 0,00 0,00 2,25 J2,00 8,50 o. 7.5 0,00 0,00 l .57,2.5 ciJ

Mea.n 11.50 l. .58 11,00 5,8J 0,00 0,00 J, 58 0,08 7,8J 22. 58 20, 58 4,67 0,00 0,00 89,2)

Au!".,, 19?4 1,0 2.5,17 O. 58 J4, ,58 66,6? 0,00 0,00 72, 50 0,17 1.5,2.5 J,5,08 12,50 12,?.5 0,00 0,00 J 275,2.5 2.5 22.oe 0,?5 1;1,25 J 1 ,00 .0,00 0,00 ,56,42 0,06 1),17 24,17 17,00 4,92 0,00 0,00 ) 210,82 .5,0 JJ,17 6,42 26,00 7,08 0,00 o.oo 51,17 0,00 17,00 )9,92 21,6? 1),17 0,08 0,00 ) 215,68

~ean 26,81 2. 58 JJ,94 )4,92 0,00 0,00 60 OJ 0,08 1.5,11, J),06 17,06 10,28 0,0) 0,00 2)),9)

~·.~a.n 1,0 26,)2 J,22 10,139 J4,6.5 0,00 0,0) 49,46 0,04 9,lJ 9,18 )0,18 JJ,92 0,07 0,00 11 20?.09 Mean 19,29 J,71 9,.57 2),15 0,00 0,02 tyl .)8 0,04 ?,SJ 9,66 2J,8) 27,134 0,08 0,00 11 lT.),10

APPENDIX E continued

Table III: ~1onthly mean number per liter (#10 Van Dorn) of zooplankton at Site III of the Big Eau Pleine Reservoir.

lluber Depth of Total in Cerio- ~- Lepto- Calan- Cyclo- Rotl- Ephl- O■tra- Date■ of

::o!lt'l ~ Darhnta d<'-p1rn1a osoma ~ Macrothrix L■ld1e,;1a Ch):dOI'\111 £2!:L. ~ Naupl11 poida !m.. pia.la .52!!L.. ~ ~

S•pt., 1973 1,0 _54.88 5,15 4J,75 55,.50 o.oo 0,00 270.62 0,00 12.25 lJ,88 15,J8 4 • .50 o.oo 0,00 2 476,.51 2.5 .52.12 7,62 5),00 25,75 0,00 o.oo Jfu:,00 0,12 15,00 17,62 26.25 ?,25 0,00 0,00 2 '66,?3

t:ea.n 5),50 6.68 118,JB 110.62 0,00 0,00 )16,Jl 0,06 lJ,62 15. 75 20,82 5,88 0,00 0,00 .521,62

C•ct,, 19?) 1,0 60,75 6,75 8.00 126.00 o.oo 0,00 140,2.5 o.oo 46,75 18,.50 4),2.5 2,2.5 0,2.5 0,00 1 i..52. 75 2,5 Jl..50 5.25 12.00 68,00 o.oo o.oo 166,25 0,00 1).25 17,00 16,75 0.75 0,25 0,00 l :,:,1.00

f!ean 46.12 6,00 10.00 97,00 o.oo o.oo 15),25 0,00 JO.CO 17,75 :,o.oo 1..50 0,25 o.oo )91,87

~ov., 19?) 1.0 5,50 0,00 0,00 8.50 0,00 o.oo 2,25 o.oo 1:,,25 0,25 ),75 2, 50 0,00 o.oo 1 :,6.00 -..J 2.5 .5-25 0,00 0,00 9,25 o.oo o.oo 4,75 o.oo 9, .50 0,2.'i J,2.'i 2,2.'i 0,00 0,00 l J4,50 I.O

~;ean 5,)8 a.co o.oo 8,88 0,00 0,00 ),50 o.oo 11,)8 0,25 :, • .50 2,'.!6 o.oo o.oo :,5.21

Dec,, 197J 1.0 4,75 0,00 0,00 J,?5 a.co 0,00 1.00 o.oo 9,So o.sa s. So 14,00 0,00 0,00 l )9,00 2.5 4,25 o.oo 0,00 .'i, So 0,00 0,00 2,50 0,00 10,75 1,50 9,00 ?,00 o.oo 0,00 1 40,50

~:ean 4,So o.oo · 0,00 4,62 0,00 0,00 1.75 0,00 10.12 1,00 7,2.5 10 • .50 o.oo 0,00 )9.?4

Ja!"l." 19?4 1.0 0,25 o.oo o.oo 2,.50 a.co 0,00 18,7.5 0,00 10.25 0,75 29,00 2.25 0,2.5 o.oo 1 64,00

Hean 0,25 o.oo o.oo 2.50 0,00 0,00 18,75 0,00 10.25 0,75 29,00 2,25 0.25 0,00 64,00

~e~. • 1971+ 1,0 0,00 o.oo 0.25 0,8) o.oo 0,00 1,67 0,00 0,2.5 o.oo :,.BJ o.oa 0,00 0,00 :, 6,91 ~!ean o.oo o.oo 0,25 0,8) 0,00 0,00 1,6? 0,00 0,25 Q,00 :,.a:, 0,08 0,00 0,00 6,91

t~ •• 19?4 1,0 0,00 o.oo 0,00 o.oo o.oo 0,00 0,00 0,00 o.oo o.oo 0,2.5 0,00 0,00 0,00 1 0.2,

!inn o.oo 0,00 o.oo o.oo 0,00 0,00 0,00 0,00 0,00 o.oo 0,2.5 o.oo 0,00 o.oo 0.25

Apr., 1971+ 1,0 0,2.5 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,2.5 0,7.5 0,25 0,00 0,00 1 1,.50 ~~ea.n 0,25 0,00 o.oo 0,00 0,00 o.oo 0,00 0,00 0,00 0,2.5 0,7.5 0,25 0,00 0,00 1, .50

APPEJ IDIX E continued

Table III (continued.) : Monthly mean number per liter (#10 Van Dom) of zooplankton at Site III of the Big Eau Pleine Reservoir.

lfu11ber Depth of Total

!I'\ Cerio- Dtaphan- Lepto- Calan- Cyclo- Rott- Eph1- Oatra- Date■ ot ~ ~ Ilaphnl.3. ~ oso:,a ~ Hacrothr1x Ley:d1fi1a Chy:dorua ~ ~ NauplU ~ !!.a. plala ~ ~ ~

Lay, l??U 1.0 6'3,50 0,75 0,12 7,62 0,00 0,00 0,.50 0,00 J,00 11,2.5 122,00 11,00 0,25 0,00 2 2S?.99 2,5 61,00 0.12 0,12 2,75 0,00 0,00 0,J'3 0,00 2,00 9, .50 97,J9 51,62 0,00 0,00 2 225,7.5 5,0 :,2.ee 0,.50 0,00 1.62 0,00 0,00 0,25 0,00 l,12 7.12 67,J8 9),12 0,12 0,00 2 169,11

J~can 5•,lJ 0,46 0,08 4,00 0,00 0,00 0,J8 0,00 2,JJ 9,29 95,.59 61.2.5 0,12 0,00 227,6)

Juno,, 19;,i. 1.0 7-•. 15 1. .50 0,12 25,J8 0,00 0,00 14.62 0,25 27,12 15,ee 25,88 51,JB 0,12 0,00 2 2)7,00 2,5 46,12 0,25 0,12 9,l? 0,00 0,l'U 7,J8 2,00 14,25 7,62 12,J8 15.62 0,00 0,00 2 U4,P6 5" .. 20. '.'5 0,62 o.oo 1.00 0,00 0,00 1,00 O,J8 6,00 1.50 6.62 1.75 0,00 0,00 2 J9,62

!-lean 11?,21 o. ?9 0,0/3 12,00 0,00 0,00 7,67 0,88 15,?9 .8.JJ 14,96 22,92 0,04 0,00 lJ0,67 (X)

0 .. tt..:ly, 19-;'4 1,0 20, .50 0,00 1.00 6,50 0,00 0,00 1,75 0,00 14,25 20,50 J5,25 4,50 0,00 0,00 l 104,2.5

2.5 l?,00 o. 50 8.25 1.75 0,00 0,00 1.00 0,25 8,00 8,25 lJ,50 0,75 0,00 0,00 1 .59,2.5 5,C lJ'J,25 J.75 1. 50 o • .50 o.oo 0,00 0,00 0,00 5,75 8,00 17,75 0,?5 0,00 0,00 l 168.25

!!can 55,92 1., .. 2 J, ,58 2,92 ·o.oo 0,00 0,92 0,00 9,JJ 12.25 22.17 2,00 0,00 0,00 ll0,S9

I:.:.;;.., ~q';"J. 1,0 2e.25 0,25 '.!2,50 ?8,62 0,00 0,00 19,62 0,12 12,J8 2),50 2J, ?5 4,J8 0,00 0,00 2 22),J? 2,5 32.00 o.oo 29,50 66,00 o,co 0,00 21.75 0 • .50 11,12 21.00 29,50 J,12 0,00 0,00 2 2ll•,49 5.fi e6,t18 0,12 15.1:2 5,88 0,00 0,00 2,75 0,12 111,oe 12.25 20,62 2,00 0,00 0,00 2 161,12

}'ean 49,04 0,12 25,87 50,17 0,00 0,00 111, 71 0,25 12,?9 18,92 24,62 J,17 0,00 0,00 199,66

Sep~., 19~ 1.0 J2,50 0,00 5),?5 159, 50 0,00 0,00 126,00 0,25 19,75 29,00 11,25 25,.50 0,00 0,00 l 4.57,.50 2,5 I;•), 75 0,00 70, .50 l','li, 75 0,00 0,00 166,00 0,25 14,.50 ;8,00 111,00 28,00 0,00 0,00 l ,.6, 7.5 5.0 1~. ?~- 0,?5 41,25 20,50 0,00 0,00 101.25 0,00 6,25 4,75 J,50 7,25 0,00 0,00 l 203.75

}:ean J0,6? 0,08 55,17 118,25 0,00 0,00 1)1,08 0,17 lJ,50 2),92 9,,58 20.2.5 0,00 0,00 402,67

1:ean 1,0 26,99 1,15 10,?J 36,52 0,00 0,00 45,92 0,0.5 12,98 10,)J 24,60 14,28 0,07 0,00 lJ lRJ.62 l~ean 26,£9 1,20 11,0J ?6,29 0,00 0,00 49,?J O,ll 9,95 e,:,,1 20,18 10,19 0,0.5 0,00 l) 16). ?6

APPEIIDIX E continued

':'3.lile N: Monthly mean number per liter (#10 Van Dorn) of zooplankton at Site N of the Big Eau Pleine Reservoir.

tlumber Depth of Total

in Cerio- Q.t:trhan- L,:,pto- Cal:ln- Cyelo- Roti- Ephi- Oatra- Datea of ro~th ~ D~pr.n1a darhnb osorn;i. ~ llaerothrix Le,ldlc;ta Ch•rdorus ~ oida tlauplU ~ ill:!... ptala ~ ~ ~

Sept,, 197) 1,0 47,62 J,25 ;>i;,25 141,88 0,00 0,00 120.12 o.oo 15.00 lJ,25 11.62 9,12 0,00 0,00 2 :,86.11 2,5 91,;,5 0,Jfl 41.62 129,88 0,00 0,00 167,12 0,00 1J.J8 lJ,88 10.25 J,50 o. 38 0,00 2 4)'3,(:11 .5,0 1,1,3~ 2,75 47, 50 1).25 0,00 0,00 176,12 0,12 5,J8 9,JO 7,50 0,12 0,00 0,00 2 JOJ, .50

!lean 49,08 2,lJ )7,79 95,00 0,00 0,00 154,45 o.OI• 11,25 12,17 9,79 4,25 0,1) 0,00 J76,08

Oct,, 197) 1.0 19,75 J,25 5,75 4J,?5 0,00 0,00 75,25 0,00 12,75 16.50 12 • .50 1.2.5 0,50 o.oo 1 191.25 ;, • 5 :l.00 J,75 17,75 61.25 0,00 0,00 l)'• • .50 0,00 9, 50 10,25 7,;,5 0,00 0,00 0,00 1 275,25 5,0 15. 50 2,00 16,00 15,50 0,00 0,00 226,00 0,00 8,00 16,75 17,25 0,00 0,75 0,00 1 J17,75

0) t:ean 22,08 J,00 1),17 40,17 0,00 0,00 11► 5,25 0,00 10,08 14,50 12,JJ 0,42 0,42 0,00 261,42 ~

J;_ov,, 197) l.'.l 15.00 o.oo o.oo J0,75 o.oo o.oo 1.50 0,00 7,25 0,00 J,75 2,.50 0,25 0,00 1 61,00 2,5 6.50 o.oo 0,00 28,00 0,00 0,00 11,0Q 0,00 5, .50 0,75 J,7.5 1.75 0,00 0,00 1 50,25 5,0 J,75 0,00 0,00 5,75 . 0,00 0,00 11,00 0,00 2.50 0,75 4,00 1.50 0,00 0,00 1 22.25

l'.~M 8.42 o.oo 0,00 21..50 o.oo 0,00 J,17 0,00 5.08 0.50 J,8) 1.92 0,08 0,00 44,50

liec., l97J 1,0 2,75 o.oo 0,00 7,00 o.oo 0,00 J,25 0,00 10.50 1.50 6.00 7,25 0,00 0,00 l )8,25 2,5 6.25 0,00 o.oo 12,00 o.oo o,;,5 6.00 0,00 1),25 J,?.5 6, so 2}, 50 0,00 0,00 1 71.00 5.0 5,75 o.oo 0,00 6,50 0,00 0,00 5.00 o.oo 10.00 0,75 6,50 9,50 0.25 0,00 l 44,25

l'ea.n 4,92 0,00 0,00 A, 50 0,00 0,08 4,75 0,00 11.25 1.8) 6,JJ lJ,42 0,08 0,00 51,16

Jan,, 19-;,q 1,0 0,25 0,00 0,00 2,00 o.oo 0,00 ),50 0,00 ),00 · o. 75 7,75 lJ,50 0,00 0,00 l J0,75 2,5 o._'ill o.oo 0,00 2.25 o.oo 0,00 0,25 o.oo 2.25 l.?5 lJ,?5 4,?.5 0,00 0,00 l 25,50

Mean 0,)8 0,00 0,00 2.12 o.oo o.oo 1,88 0,00 2.62 1.25 10,75 9,12 o.oo 0,00 28.12

hb,, 19-,-. 1,0 0.12 0,00 0,00 0,12 0,00 0,25 0,88 0,00 2.00 0,50 59,25 0,)8 0,12 0,00 2 6).62 Hean 0,12 0,00 0,00 0,12 o.oo 0,25 0,88 o.oo 2.00 0,50 59.25 0,)8 0.12 0,00 6J.62

::,r,, 19-,-. 1,0 0,00 0,00 o.oo 0,00 0,00 0,12 0,25 0,00 0,25 0,12 28,?5 o.oo 0,00 0,00 2 29,49 2.5 o.oo o.oo 0,00 0,00 o,oo o.oo 0,00 o.oo 0,00 0,00 a.so 0,00 0,00 0,00 l 0.50

1:ean 0,00 0,00 o.oo 0,00 0,00 0,06 0,12 o.oo 0.12 0,06 14,62 o.oo 0,00 0,00 14,98

APPElIDIX E continued

Table N (continued): Monthly mean number per liter (#10 Van Dom) of zooplankton at Site IV of the Big Eau Pleine Reservoir.

llu•'bolr Depth of ToUll

!:1 Cerio- Dlarhan- Lepto- Calan- Cyclo- Roti- Ephl- Oatra- n .. tea of ~ ~ Daphnla d•]'hnla O!JU/f,rl. ~ Macr,,thrtx Le,tdlt:ia Ch,rdonis dora ~ llaupl11 poirta !!!!.. pt:1ls ~ ~ ~

Apr., 19?'1 l.O 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 8,75 0,00 0,50 o.oo 0,00 1 9,2S 2,5 0,25 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,50 1.00 0,00 0,00 0,00 1 l,?S 5,0 0,00 0,00 o.oo o.oo 0,00 o.oo 0,00 0,00 0,00 0.25 1.50 0,75 0,00 0,00 1 2, 50

!'.can 0.08 o.oo 0,00 0,00 0,00 0,0(1 0.00 0,00 0,00 J,17 0,8J 0,112 0,00 0,00 4,,50

?:ay, 19'/4 1,0 69,JA 0,J8 0,00 l.50 0,00 o.oo 0,12 0,00 1.,50 16,12 1J8,J8 9J,62 0,00 0,00 2 )21,00 2.5 Jg,M 0,00 0,00 1.00 0,00 o,uo O,J13 0,00 1.62 211,75 95, 50 65,62 0,00 0,00 2 22?, 15 5,0 yr ,ee 0,62 0,12 0,88 0,00 0,01) o.eo 0,00 O,J8 10,62 6J,75 )9,75 0,00 0,00 2 151,00

Mean 47,71 O,JJ 0, Q/1 l.lJ 0,00 0,()0 0,17 0,00 1.17 17,16 99,21 66,JJ 0,00 0,00 2JJ,?5 Cl) N

cu::e, 19'/4 l.O 84.2.5 0 • .50 0.12 7,12 0,00 0,00 25,12 o.88 21.75 8,25 21,75 79,50 0,00 0,00 2 249,24 2,.5 24, 7.5 c.12 0,00 0,88 0,00 a.co 2,00 0,12 28,75 7,12 16,62 6,00 0,00 0,00 2 66,36 .5,0 12,75 0,12 0,00 O,J8 0,00 o.oo 0,75 0,12 20.25 5,75 17,50 11,12 o.oo 0,00 2 61,?4

~'.ean 4-:,. se 0,2.5 0,()/, 2,79 -0,00 0,00 9,29 O,J7 2J.,58 7,()11 18,62 29,07 o.oo 0,00 1J2,4J

July, 1974 1.0 18,75 o.oo 1. 75 2,50 0,00 o.oo 1.25 0,00 40,50 32,50 24, 75 1,75 0,00 o.oo l 12J,75 2.5 1? "'lt: ....... ,..,, 0,00 J.75 1.50 0,00 0,00 0,25 0,00 110,00 15.50 11,75 1.50 0,00 0,00 l 107,00 5,0 29,.50 o.oo 0,00 0,50 0,00 0,00 0,00 0,00 16,75 J,25 5,75 0.2.5 0,00 0,00 l ,56,00

l!ean 27,00 0,0:J 1.8J 1,50 0,00 0,00 0,50 0,00 32,42 17,08 14,08 1,17 0,00 0,00 95,58

1-.u;:., 1971• 1.0 J?,08 0,08 35,25 55, .58 0,00 0,00 15,75 0,00 19,42 J4,17 57,50 4,33 0,00 0,00 ) 2~.16 2.5 y,,92 0,00 29.92 JJ,87 0,00 0,0() 19,50 0,17 11,50 1.8,08 47,00 2,50 0,00 0,00 ) 197,46 5,0 J2,00 O,JJ 24.17 6,oe 0,00 0,00 16.25 0,17 11,08 19,17 14,92 4,67 0,00 0,00 3 128.64

Xea.n J4,67 0,111 2'),76 )1.84 0,00 0,00 17,17 0,11 14,00 2).81 J9,81 ),8) 0,00 0,00 19.5.16

Sept,, !9'/4 Not Sampled

:.e.\!\ 1.0 24,,58 0,62 .5,59 24,)5 0,00 O,OJ 20.,58 0,07 11,16 11.0:, :,1.00 17,81 0,07 o.oo 12 146,89

?iea.n 19,59 0,119 6,89 17,06 0,00 0,0J 28,14 0,04 9,46 8,26 24,12 10,93 0,07 o.oo 12 125,08

APPENDIX E continued

Table V: Monthly mean number per liter (#10 Van Dom) of zooplanlrton at Site Vin the Big Eau Ple:!.ne ;{eservoir.

lh.111ber Det>th ot Total

!.~ Cerio- D1aphan- Lepto- Calan- Cyclo- Rot1- Ephl- Oatra- Dataa of ront'"t Ve~crs Daphn1a daphnia onoma. Bos111ina Macrothrlx Lexdtc;la Chxdorua ~ ~ Naupl11 po1da !,!!!,_ piala ~ ~ !.:!2!!.!

Sept,, 1913 1.0 Jl,5'l 0,12 Jl,12 .5'1,62 0,00 0,00 ma.es o.~5 17,.50 9, .50 10,00 5,62 0,00 0,00 2 )'+9,09 2,5 25, 75 O,Jll 46,25 27,12 0,00 0,00 l(h, 12 o.oo 8,00 J,2.5 8,12 2,75 0,00 0,00 2 2!l.5.~ 5,0 J5,12 0,62 5J,50 2.25 0,00 0,00 )07,811 O,J.'l 2,813 J,88 4, .50 0,00 0,00 0,00 2 407,01

10.0 49,00 2,00 55,75 7, ?_5 0,00 0,00 J 5:),? 5 o.oo 1,25 J,7.5 20.25 2,00 lJ,25 0,00 1 51J,7.5 Mean )5,.59 0,78 46,66 22.81 0,00 0,00 25J, 78 0,16 7,1n 5,10 10,72 2,.59 J,Jl 0,00 Jl'-tl,91

Cct,, 1913 1.0 25.es 1,62 11.62 20.00 o.oo 0,12 l','ti,12 o.oo 11.88 6,75 16.00 0,00 0,12 0,00 2 26/l,ll 2,5 ~5. J :! 7,?5 2,JP ?0,75 0,00 0,00 111;>,00 0,00 12.00 !l,12 17,25 0,00 0,00 0,00 2 2?5,137 5,0 25,flS 0,75 1?,JI' 22,118 0,00 0, l,,-) l?ilJ1f\ 0,00 8,62 5,50 lJ,J!l 0,12 0,00 0,00 2 26".)9 CD 7.5 :,1.,00 c. 50 22.50 2J.OO o.oo 0,00 275.25 0,;:>5 9,00 11.00 14. 75 0,00 0,00 0,00 l :,eo.25 w

~·.ean 25,47 2. 5J 12,22 21,66 0,00 O,OJ 202,:i, 0.06 10,JB 7,84 15,J4 O,OJ O,OJ 0,00 29(1,12

::ov,, 197:l 1.0 10,00 0,00 0,00 17,75 0,00 0,00 5,50 0,00 10.25 0,00 4,.50 1, .50 0,00 o.oo l 49.So 2,5 11 ,75 0.:15 0,00 17,00 !),00 0,00 5,25 0,00 9,25 0,25 7,25 0,00 0,25 0,00 l 48,25 .5,0 ~ .2 5 0,00 (l,00 19,2.5 0,00 0,00 7 • .50 0,00 10,7.5 1,2.5 6,?.5 J,.50 0,25 0,00 1 .57, .50

l'!e:\.'1 9,00 0,08 0,00 18,00 0,00 0,00 6,NJ o.oo 10,08 o.~o 6,17 1,67 0,17 0,00 .51, 7.5

!:cc .. • l97J l.O J,7.5 0,00 0,00 7,25 0,00 0,00 1.25 0,00 .5,00 0,?.5 2,50 1.25 0,00 0,00 l 21.25 ,., < s.oo 0,00 0,00 9, 50 0,00 (1,00 2,25 0,00 7,75 0,00 4,25 J, .50 0,00 0,00 1 J2.25 •-•.,J

5.0 l.00 0,00 0,00 111 .50 o.oo 0,00 ),25 0,00 10,75 1. 50 ?,00 5,75 0,00 0,00 1 48,7.5 ?.5 4. :,o 0,00 0,00 5,00 0,00 0,00 4,75 0,00 2,2.5 0,50 .5,00 1.75 0,00 0,00 1 2J.7.5

P.ea.."\ 4.81 0,00 0,00 9,06 0,00 0,00 2,88 o.oo 6,44 -0.56 4,69 J,06 0,00 0,00 Jl,.50

Jan,, 1974 1.0 1, .50 0,00 0,00 0,7.5 0,00 0,00 0,50 o.oo 6,.50 J,.50 49,.50 6,7.5 0,00 0,00 l '9,00 2,5 2.50 o.oo 0,00 2,25 0,00 0,00 0,00 0,00 6,50 2,75 29,25 4,25 o.oo 0,00 l 4?.,50

Y.ean 2.00 0,00 0,00 l. .50 0,00 0,00 0,25 0,00 6,50 J,12 J9,JB .5, .50 0,00 o.oo 58,25

!"e'::,, 1974 1.0. 1 • .50 0,00 0,00 0,67 0,00 0,42 0,17 o.oo 7,08 2,42 48,75 .5,42 0,25 0,00 J 66.611 2.5 o. _)'.) 0,00 0,00 0,50 0,00 0,08 0,08 0,00 2,58 2,08 26,92 1,.58 0,17 o.oo J J4,57

~ean 1.04 0,00 0,00 0,58 0,00 0,25 0,12 0,00 4,8J 2,25 )7,84 J,.50 0,21 0,00 50,62

APPENDIX E continued

Tab~e V (continued): Monthly mean number per liter (#10 Van Dorn) of zooplankton at Site V of the Big Fau Pleine Reservoir.

Mwtber Depth or Total

in Cerio- Diaphan- Lepto- Calan- C:yclo- Roti- Bphl- Oetra- tatH of ~'.or.th !~e~ DP.phnb da.phnta. OfOJn;\ ~ Macrothrlx Le,}'.1111,ta Ch,ldorua !!_'?.£:}_ ~ Naupl11 polda f!!!... p111la ~ ~ !'.!!!!.!

r:ar., 19~ 1,0 o.oo o.oo 0,00 0,00 0,00 o.oo 0,12 0,00 0,00 0,25 26.12 0,88 0,00 0,00 2 2?,)? 2,5 0.00 0,00 0.00 0.12 0,00 0,00 0,00 0,00 0,00 0.12 ),B8 0,12 o.oo 0,00 2 lt,24 5,0 o.co 0,00 0,00 0,00 o.oo (),0(\ 0,00 0,00 0,00 0,00 l),?5 0,25 0,00 o.oo 1 14,00

~'.ean o.oo 0,00 o.oo o. 04 0,00 0,00 0,04 0,00 o.oo 0.12 111. 58 0,42 0,00 0,00 15.20

Apr,, 19~ 1.0 0,00 o.oo o.oo 0,00 0,00 0,00 0,25 0,00 0,25 0,00 0,75 o. 50 0,00 o.oo 1 1.15 2,5 0,00 0,00 0,00 o.oo 0,00 r,. r10 0,00 0,00 0,00 0,25 J,25 0,75 o.oo 0,00 1 4,25 5,0 0.00 0,00 0,00 0,00 0,00 o.oo O,U(J 0,00 0,00 0.00 2,50 LOO o.oo 0,00 1 J,50 7,5 o.oo 0,00 0,00 0,00 o.oo 0,00 0,00 0,00 0,00 0. 50 1.00 0,75 0,00 0,00 l 2.25

CX) t-~ean o.oo 0.00 o.oo o.oo o.oo 0,00 0,06 0,00 0,06 0,19 1,88 0,75 0,00 o.oo 2.94 ,&:..

:'.A:y, 19~ 1.0 56,,;2 O,J8 0,00 O,J8 o.oo 0,00 0.00 0,00 1.25 7,25 29?.12 50,88 o.oo 0,00 2 51),1!8 2,5 1,2 ,50 0,12 0.00 0,25 0,00 0,00 0,00 0.00 1.)8 16.00 J24.75 115,E\8 0,12 o.oo 2 !01,00 5,0 ]'J, :'5 0,!2 0,;8 0,62 .o.oo o.oo 0,00 0,00 O,J8 6.J8 210.Je J9,50 o.oo 0,00 2 JJ7,0l

10.0 6,Jf: 0,00 0,12 0,12 0,00 O,uO o.~5 0,00 O,Jl'l 16.88 240.ee ,58,25 0,62 o.oo 2 J2J.~8 ?'.ean ~1.19 0,16 0.12 O,J4 0,00 0,00 0,06 0,00 0,85 11.6J 28J,28 66,lJ 0,19 0,00 :,<)4,05

.:i.:re, :?..9~• 1.0 ~9.)9 0,00 0,00 0,75 0,00 0,00 6.25 0,25 J0,00 .10,12 18,50 J0.62 0,12 0,00 2 125,99 2.5 27,;,5 0,12 0,00 l.00 0,00 0,00 1,.25 0.12 '.ll.88 12.25 11.62 8,12 o.oo 0,00 2 96,61 5.0 l ~, ;(I 0,00 o.oo 0,38 0,00 0,00 0,62 0,12 ;~. 50 11.00 15,25 o.ee 0,00 0,00 2 77. l)

10,0 ~-6.9~ 0,00 0,00 0,62 0,00 0,00 O,JB 0,00 1),50 5.50 25.ee 1.50 1.62 o.oo 2 75.~9 ~:ean ,.4,72 0.03 0,00 0,69 o.oo 0,00 2,/\8 0,12 27,22 ,9,72 17,81 10.28 0,44 0,00 9),91

.:.ily, 19~ 1.0 11,25 0,00 0,25 0,75 0,00 0,00 2.50 0,00 26,50 25.50 2J,75 :,2.25 o.oo 0,00 l 122,?5 2.5 9,25 0,00 0.50 0,25 0,00 0,00 6.25 0,00 49,50 20.50 10,50 2,00 o.oo 0,00 l 9~.75 5,0 10.15 o.oo 0,00 0. 50 o.oo 0,00 1, 50 0,00 :,<),25 2.25 6.25 0.25 o.oo o.oo l 60,?5

10,0 0,75 o.oo 0,25 0,00 0,00 0,00 0,75 0,25 1.00 0,00 0.25 1,75 0,75 0,00 1 5,75 !-:CM e.co o.oo 0,?.5 0.112 0,00 0,00 .J,00 0,06 29,06 12.06 10.19 9,06 0,19 0,00 ?2,29

APPENDIX E continued

Table V (continued) : Monthly mean number per liter (#10 Van Dom) of zooplankton at 8i te V of tl!e 131g Eau Pleine Reservoir.

N1111'ber I:epth of Total

1n Cerio- Dtaphim- Lepto- CalM- Cyclo- RoU- Bph1- Oatra- Date■ of ro~th !·'.c+..ers Darhn1a O;\phnla onona ~ Macrothr1x Le;r:d1t;1a Ch;r:donis ~ 2ll!L Naupl11 ~ !!!!_ p1als ~ ~ ~

Aug., 19?4 !.O 22,75 o.oo e,25 25.25 0,00 0,00 7.75 0,25 51.50 14.88 JJ.88 1.00 0,00 0,00 2 165,51 2,5 40,75 o.oo 19.00 15.12 o.oo o.on 4,)8 0,12 20,62 17,50 2),25 0,75 0,00 0,00 2 141,49 5,0 22 ,38 0,00 2J.25 6.00 0,00 0,00 11,00 0,00 10.62 16.38 20.62 0,75 0,12 0,00 2 104. 12

lC.O 2.5.es o.oo 12,62 1,89 0,00 o.uo 2,J9 o.oo 8,J8 15.J8 17.25 l.JA 0,12 0,00 2 85.27

MelJt 27,94 0,00 15.78 12,06 0,00 o.oo 4.6J 0,09 22,78 16,04 2J,75 0,97 0,06 0,00 121,,10 CX)

Sept,, 19?4 1,0 J9.25 0,00 27,25 lJJ,00 o.oo 0,00 120, 50 0,50 J4,00 24,25 17,50 297,25 0,00 0,00 l £9J,50 u, 2,5 !;.:,, 75 0,00 17,00 9J,00 0,00 0,00 7'-1,50 0,00 J2,75 14,25 5,00 107,75 0,00 0,00 l 389,00 5,0 69,00 0,00 29,25 29.25 0,00 0,00 49,50 1.75 14,25 1.00 2,25 14,50 0,00 0,00 l 210,75

lC,0 47,25 0,00 2J,50 ),75 0,00 0,00 8,00 0,00 45,25 17,00 5,25 14,00 o.oo 0,25 l 164.25

Mean 50.06 0,00 24.25 64,?5 d,oo 0,00 6).12 0,56 Jl,56 14,12 ?,50 108,JB 0,00 0,06 J64,J6

fean. ::.o 17,95 0,16 6.04 20.09 0,00 0,04 )9,06 0,10 15.52 8,05 42,22 JJ,J8 0,04 0,00 lJ 182,65 1!ean 16,91 0,28 7,t,.; 11.68 0,00 0,02 41.51 0,08 12,09 6,40 J6,J9 16,JJ 0.35 0,00 1:, 149,68

APPENDIX E continued

Table VI: !\~onthly mean number per liter (#10 Van Dorn) of zooplankton at Site VI below the Big Eau Pleine dam.

N1111ber Depth or Total

in Ccr\o- Dtaphan- Lepto- Cal1111- Cyclo- Rotl- Eph1- Oatra- Dates ot ~ ~ ~ da.,hn1a 0!31'Jr.\il ~ Macrothr1x Lff):d1&1& Ch;i::done ~ ~ NauplU potda ~ piale ~ ~ t!!el

Se;t., 197:, 1.0 5.00 1.00 18,00 .52.e8 0,00 o.oo 69,50 o:oo 6.7.5 11.,50 1),00 47,)8 0,00 0,00 2 22.5.01 2.5 11,?5 l.JR 26,.50 16.2.5 0,00 0,00 120,)8 0,00 7,00 7,25 14,62 7,)8 0,00 o.oo 2 211,98 5.0 :;,5.00 2,1'8 21.25 !f,50 0,00 0,00 A9,62 o.oo 17,00 J,12 Jl,75 1.?.5 0,00 0,00 2 196,8?

Eean lJ.75 1.7.5 21,92 24,54 0,00 o.oo 9J,17 o.oo 10.25 7,29 19.79 18.84 0,00 0,00 211.)0

Oct,, 197.l 1,0 J.62 0.62 1.00 79,88 0,00 0,00 29,62 o.oo 2.12 6,50 12.12 11.00 0,62 0,00 2 147,10 2,5 :?,CO 1.25 J,_50 67,00 0,00 O,rlO 61,25 0,00 1.88 4,12 10,75 5,2.5 0,12 o.co 2 157.12 5.0 5,$[l l. ,50 1,,00 45,00 0,00 0,00 )9,50 o.uv 5,75 2,25 15,12 1.12 0,12 0,00 2 120,j_lj•

ex, t:ean J.BJ 1.12 2,8J 6J,96 0,00 0,00 4J,'•6 0.00 J,25 4,?9 12,66 5,79 0,29 0,00 141,48 O'\

:.ov., 197) 1.0 J,J9 0,12 0,00 J0,88 0,00 0,00 5,62 0,00 J.62 0,75 4,?5 .5,88 0,J8 0,00 2 .55,)8 2.5 6.Je 0,00 0,00 J2,BS 0,00 o.oo ?,J8 0,00 4,12 1,00 6,88 2,2.5 0,.50 a.co 2 61,:19 5,0 J,?5 0,00 0,00 JJ, 50 0,00 0,00 J,75 0,00 J,62 0,62 .5-25 2.25 0,00 0,00 2 .52, 74

!'.ean 4,50 o.OI• 0,00 J2.42 · o.co 0,00 5,56 0,00 J,79 0, 79 ..5,6J J,46 0,29 0,00 .56. ,i

!:ec., 197.l !lot Suipled

:.!!"!.,. 1°74 1.0 1.2..5 0,00 0,00 o • .50 0,00 0,00 0, .50 0.00 lJ,00 o. 7..5 2.5, ..50 4,2.5 0,00 0,00 l 4..5,7.5 ~-5 l.00 0,00 0,00 0,75 0,00 o.oo 0,..50 0,00 11,00 1. 50 18 • .50 4,75 0,00 0,00 l :,e.oo 5,0 0 • .50 0.00 0,00 0,25 0,00 0,?5 o. 50 0,00 10.50 1.00 27,00 2, .50 0,00 0,00 1 42, .50

J!ean 0.92 0,00 0,00 0,50 o.oo O,Ofl 0, .50 0,00 11.50 1,08 2J,67 J,8J 0,00 0,00 42,08

Feb., 1974 1.0 o.oo 0,00 0,00 0,75 0,00 0,00 0, .50 0,00 5,25 J.15 25,00 7,50 0,00 0,00 1 42,75 2,5 0,,50 0,00 0,00 0,?5 0,00 0,25 0,25 0,00 lf,00 9,75 2J • .50 2,25 0,00 0,00 l 41.2.5 .5,0 2,75 o.oo 0,00 1. .50 0,00 0,00 0,25 o.oo 7,00 2J • .50 40,25 J,00 0,00 0,00 l ?8,2S

!·~ea.n 1,08 0,00 0,00 :!.,00 0,00 0,08 O,JJ 0,00 5,42 12,JJ 29,,58 4,25 0,00 0,00 !i4. 09

"ar,, 1974 1.0 0,00 0,00 o.oo 0,00 o.oo 0,00 0,00 0,00 0,00 2.25 11,75 0,,50 O,OQ 0,00 l 14,,50 2,5 0,00 o,co 0,00 0,00 0,00 0,00 0,00 0,00 0,00 6,25 22.25 0,25 0,00 0,00 l 21'1,7.5 5,0 0,25 0,00 0,00 0,00 0,00 o.oo 0,00 0,00 2.00 12.50 126,75 2.00 0,00 0,00 l 14J,50

J:eiU'l 0,08 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,67 7,00 ..5J,56 0,92 0,00 0,00 62,2.5

APPE-lDIX E continued

':'..13.ble VI (continued) : r-1onthly mean number per liter (#10 Van Dorn) of zooplankton at Site VI below the Big Eau Pleine dam.

lha•ber Depth of Total

in Cerio- Dtnphan- Lepto- Calan- Cyclo- Rot1- Eph1- Oatra- llatq of ~·o~+:.h ~ Daphnta d;;phnia osoma. ~ Macrothrix Le:z:dti;ta Ch:z:dorua ~ ~ NauplU poldn ~ p1nls ~ ~ 1:ecna

Apr,, 19~ !lot S&111pled

:.· .. "!.y. 1()?4 1,0 1.25 0,50 0,00 7, 50 o.oo 0,25 1. 75 0,00 0,00 14,75 58,00 4),25 0,00 o.oo 1 127,25 ~-5 1,00 0,00 0,00 2J,50 0,00 o. 50 0,2.5 0,00 0,25 16,75 87,50 28,00 0,00 0,25 1 1,58,00 5,0 2,75 0,00 0,00 6J,75 0,00 0,00 1,00 0,00 0,00 lJ,75 117,25 1.5.2.5 0,00 0,00 1 21:,. 75

Hean l,G7 0,17 0,00 Jl, .58 0,00 0,25 1.00 0,00 0,08 15.08 87,58 28,BJ 0,00 0,08 166,)2

:~e, 19'?4 1,0 lJ,12 0,12 0,00 8.)8 0,00 0,00 0,62 o.oo 14,12 7,J8 9,62 2.62 0,25 0,00 2 56,2) 2.5 29,75 0,25 0,00 10.25 o.oo 0,00 0,62 0,12 8,88 lJ.25 J5,JB 1.75 0,00 0,00 2 100.25 (X)

5,0 36.JE 0,12 0,00 ll',25 0,00 0,00 0,62 0,00 6,00 10.25 67,62 J,00 0,00 0,00 2 142,2'• --..1

lleR.n 26,42 0,17 0,00 12.29 0,00 0,00 0,62 0,04 9,67 10.29 J?,:!fi 2,46 0,08 0,00 99,58

Jul:,, 19;>!1- 1,0 28,88 0,00 0,00 0,75 0,00 0,00 4,00 0,12 J9,12 6,88 8,00 2J,J8 0,25 0,00 2 91,:,6 2,5 24.~e 0,00 0.25 0.50 •0,00 0,00 4,00 o. 50 17,25 J.88 4,62 25,00 0,00 0,00 2 ao.ea 5,0 ;5,75 0,00 0,00 0,25 0,00 0,00 5,12 0,25 22.62 4,50 9, 50 19,)8 0,25 0.25 2 9?,87

J.:ean 29,f¼ 0,00 0,08 0.50 o.oo 0,00 l1,J7 0,29 19,66 5,09 7,J7 22.59 0,17 0,08 90,04

.\u;,:,, 1974 1.0 J.5,00 O,JJ 21,17 112.JJ 0,00 0,08 64,75 0,08 20,42 16.00 21,00 17.50 0,00 0,00 J ;08,66 2,5 '!}.92 0.25 17 • .:,ll 112.42 0,00 0,08 6),00 0,00 1.5.17 lJ,00 19,8) 11,.50 0,0'3 0,00 J 27?,BJ 5,0 15,0'l O,JJ 5,92 26,00 0,00 0,00 J6 • .50 0,00 10,8) J2.00 111,08 )9,00 0,00 0,17 J 1?9, 91

rcan 25,00 O,JO 11 •• 89 BJ,.58 0,00 0,05 :!fa, 75 O,OJ 15,t17 20,JJ 18,JO 22,67 O,OJ 0,06 255,46

::ert,. 191f !lot SaJ11pled

::ean 1,0 9,15 0,27 4,02 29,J8 0,00 0,0) l?,69 0,02 8,li4 7,05 18.87 16,JJ 0,15 0,00 10 111,liO

Mean 10,71 O,J6 '.l,97 25,011 0,00 0,05 20,J8 0,04 7,98 B,J6 29,57 ll,J6 0,09 0,02 10 ll?,9J

APPENDIX F

~able I: !-1onthly mean number per liter (Van Dorn total) of zooplankton at Site I of the Big Eau Pleine Reservoir.

NIU!ber Dept?i of Total in Cerio- Dl.aph!l.ll- ~- Calan- Cyclo- Roti- Eph1- O•tra- Dato• of

l:ont'i ~ Daphnia c:~1·!1nia 9.E~ ~ Macrothrix Lexd1e;1a Chxdorua ~ ill!_ llaupl11 poida f.m.. pl.ala £2!!!..,_ ~ .!:l!.!!!.~ Sept., 19?) 1.0 0.25 0.25 1.50 1.88 0,00 4,25 J.00 0,00 o.oo 2.25 l.62 162,:,8 0,00 0,00 2 l??,J8

Hean 0.25 0,25 l. 50 1.88 0,00 , •• 25 J.00 0,00 o.oo 2,25 l.62 162,JB 0,00 0,00 l??.)8

Cc~.• 19?J l,O 0,75 o.oo 0,62 7,J8 0,00 l,75 6,62 o.oo O,J8 J,50 4,00 28,12 o.oo 0,00 2 5),12

l•:ean 0,75 0,00 0,62 7,J8 0,00 1.75 6,62 o.oo 0,)8 J,50 4,00 28.12 0,00 0,00 .5J,l2

::0v., 19?) 1,0 0,00 0,00 0,00 1.00 0,25 0,50 J,50 0,00 0,00 0,25 0,25 0,00 0.25 0,00 l 6.00

rean o.oo o.oo 0,00 1.00 0,25 0,50 J. so 0,00 o.oo 0.25 0,25 0,00 0.25 0,00 6,00 (X) (X)

!" ... t::c. • l'l'>'l . ,.,, ttot Sampled

.:r-~ .• ~974 1.0 0,00 o.oo 0,00 0,75 o.oo o.oo 0,25 0,00 0,00 0.50 0,?S 1.50 o.oo 0,00 1 J,?5 ~!can o.oo 0,00 o.oo 0.75 0,00 0,00 0,25 o.oo 0,00 0.50 0.?S 1.50 o.oo o.oo J,?5

r, "·, 19?4 1.0 o.oo 0,00 o.oo 0,25 0,00 0,00 0,25 o.oo 0.12 0,00 1.12 0,81 0,00 0,00 4 2,55 ~ean 0.00 0,00 o.oo 0,25 0,00 0,00 0,25 0,00 0,12 0,00 1.12 0.81 0,00 0,00 2,55

. nr •• 19'?4 1.0 0,00 0,00 0,00 0,00 0,00 0,00 0,50 o.oo 0,00 o.oo 0,75 0.25 0,00 0,00 1 l, 50 1".ean 0,00 0,00 o.oo 0,00 o.oo o.oo 0.50 o.oo o.oo 0,00 0,?5 0,25 0,00 0,00 1,50

Afr,, 1974 1.0 0,00 o.oo o.oo 0,00 o.oo 0,00 0,00 0,00 0,25 O,?S 0,75 0.25 o.oo 0,00 1 2,00 2.5 o.oo 0,00 o.oo o.oo o.oo 0.25 0.50 0,00 0,00 o. 75 0.50 0,50 o.oo o.oo l 2.50

~!ean o.oo o.oo 0,00 0,00 0,00 0,12 0,2.5 0,00 0,12 0,75 0,62 O,JB 0,00 0,00 2.25

:-~a.y. 19?4 l.O 101.06 1.62 o.oo lJ0.69 o.oo o.oo 0,00 0,00 o,oo 4?,00 J.5,50 67,19 0,00 o.oo 2 JeJ,06 2.5 n.oo 2.25 0.12 41,62 0,00 0.12 1.50 o.oo o.oo ~.oo 2J,12 J.5,88 o.oo C,00 2 195,61

Mea.n 64,0J 1.94 o.06 86.16 0,00 0,06 0,?5 0,00 o.oo 55,50 29,Jl 51.5) 0,00 0,00 289,84

APPENDIX F continued

Table I (continued) : lb-lthly mean number per liter (Van Dom total) of zooplankton at Site I of the Big Eau Pleine Reservoir. -

lluner Depth ., t.ul

1n !im!- !!!E!!!!!- • C&lan-.,.,.._

IIM1- lpld- o.tn.- ht.ee •t ~ Xetffl !!lz!!!!! dP..p."ln1f" QIIO!:l.l. .lut1!la ~11 ~1• Oh!!!duu -- !Bill! ma. ma. IH!I -- .J1l!f !itSI

O::.ir.e, l97'1t 1.0 41•.62 0,62 0,00 1?0,88 0,00 0.12 l,9!J 1,12 Q,12 llt,06 12.00 ?6,.50 0,00 1,19 2 )2),17 2,5 21,)8 J.12 0,12 62,00 0,)8 0,)8 1,12 o.oo 0,.50 12.25 1.5.25 l?,12 0,00 0,25 2 1)),87

l"!ean )J,00 1.88 0,06 116,114 0,19 0,25 1,.5) o.,56 0,)1 1),16 1).62 46,81 0,00 0,72 228,,,.

.'uly, 19;,c. 1.0 12:!,8S l,?5 ?),25 .5,00 o.oo 0,00 8,2.5 0,00 ?,!JJ 185,.50 85,)1 216.6) 0,00 0,00 l 697,12 2,5 70,25 0,15 JJ.,50 1,?.5 o.oo 0,00 l,?5 0,2.5 5,75 190.12 41,62 201,00 0,00 0,00 l ,,,.. 7.5

r.een 100,56 1.25 .5J,J8 ).J8 0,00 0,00 5,00 0,12 6,62 Hl?,81 6),.50 20t',82 0,00 0,00 6)0.114 a: I..C

Aug,, 19;,c. 1,0 ?l,67 26,,58 )8,17 1114,8) o.oo 0,00 J.88,()lj o.oo 1),9' )18,29 100,:,:, 114), 59 0,00 o.oo :, 1,r.5..50 2,.5 J?.46 9,.50 11,)8 20,JO 0,00 o,oo )'Jl,12 0,00 9,J) 295,8J 86,86 199 • .50 o.oo o.oo ) 1061.)0

1'.ean ,., 56 18.04 24,7? 82.5? 0,00 0,00 289,60 0,00 11,6.5 )07,06 9:,,60 )21.,. 0.00 o.oo 120).)9

3e;:t,, 19~ !lot Supled

~'.t?a.!'1 1,0 :,1,02 2,80 10,J2 42,06 0.02 o,60 19,)l 0.10 2,0) .52.01 22,04 90,66 0.02 0,11 11 27).10 Hean 2),01 2.12 ?,Jl 27,26 0,04 0,6) 28.)0 o,06 1,7.5 .51,89 19,01 ;,c.,;,c. 0,02 0,07 11 2)6.21

APPENDIX F continued

Taule II: Monthly mean number per liter (Van Dorn total) of zooplankton at Site II of the Big Eau Pleine aeservoir.

haller Depth of Total in Cerio- Dia.phan- Lepto- Calan- Cyelo- Roti- lphl- Oatra- Dot" of

~ ~ Daphnla daphnla OSOllla l!!!S!!! Muzothg:!x J.e~le!a Ct!ldOru! .!12.a- .w!!_ !!!!1!lll J!!!a fera E!ill ~ Aw'fl !:.wla Se,t,, 197) 1,0 .59.ee 19.12 ,56,12 ?6.:,11 o.oo 0,00 42.5,62 o.oo 19,12 1?7,88 ».12 104,7.5 0,12 o.oo 2 992,11

2,.5 ~.oo 22.:,e 4?,12 :,e,62 0,00 0,00 41).62 0.12 1.5.2, 19',1.5 ltl,)8 ?9,)8 0,12 0,00 2 904,,.. !':ean 5.5,94 20,75 .52,62 .5?,50 0,00 0,00 1119,62 o,06 l?,19 18.5,81 4?,2.5 91,,56 0,12 0,00 948,42

Cct,, 197) 1,0 114,?5 10.2.5 8,7.5 125.2.5 o.oo 0,00 18.5,25 0,00 )l,?.5 5),00 .56,?.5 75,00 o.oo 0,00 l .7)1,2.5 2 • .5 2),25 9,?.5 6,00 4?,?.5 0,00 J,00 19),?.5 0,00 1.5,00 61,50 )l,?5 47,?5 0,00 0,00 l 4)9,50

t'.&&n )4,00 10.00 ?,J8 86,50 0,00 1, .50 189,50 0,00 2),J8 .5?,2.5 ~.2.5 61,:,e 0,00 0,00 51.5,14

::ov., 197) 1.0 ),2.5 0,00 0,00 .55,?.5 0,00 0,00 4,?5 0,00 12,00 )8,75 17,50 129,50 0,00 0,00 l 261,50 '° 2,.5 J,00 0,00 0,00 19,50 0,00 o,oo 5,25 0,00 10,?5 )0,00 l.5,00 )8,?5 0,0(1 0,00 1 122,50 0

r.&M ),12 0,00 0,00 J?,62 0,00 0,00 5,00 0,00 11.:,e Y•,38 16,2.5 84,12 o.oo 0,00 191,!7

t-.c,, 1973 1.0 J,00 0,00 0,00 1.5.50 0,00 0,00 1,2.5 0,00 6,00 46,50 19.00 1)6,2.5 0,00 0,00 1 2??,,0 2.5 2,25 0,00 0,00 11,?.5 b,oo o.oo 2,50 0,00 4,?.5 116,?5 19,?5 114,,50 0,25 0,00 1 192,00

!lean 2.62 0,00 0,00 1),62 0,00 o.oo 1,88 0,00 5,)8 46,62 19,)8 125,JB 0,12 0,00 215,00

-"·"·• 191+ 1.0 0,00 0,00 0,00 0,2.5 0,00 o,oo 0,2.5 0,00 0,00 0,2.5 1,00 2.25 0,00 0,00 1 4,00

!•:ean 0,00 0,00 o.oo 0,2.5 0,00 0,00 0,2.5 0,00 0,00 0,25 1.00 2,2.5 o,oo 0,00 4,00

Fet,, 191+ 1,0 O,C6 0,00 0,00 0,19 0,00 0,00 0,19 0,00 o.oo 0,06 1,69 0,81 0,12 0,00 ,. :,.12 ►:e1111 0,06 0,00 0,00 0,19 0,00 0,00 0,19 o.oo 0,00 0,06 1,69 0,81 0,12 o.oo J,12

~:a.r., 191+ 1,0 0,00 0,00 o.oo 0,2.5 o.oo 0,00 0.50 0,00 o.oo o.oo 0.7.5 1.2.5 o • .,. 0..00 1 l.JS r-:ean o.oo o.oo 0,00 0,2.5 0,00 0,00 0,50 0,00 o.oo 0.00 0,7.5 1.2.5 0.50 0,00 :,,2.5

A:,r,, 19'}4 Not Sa111pled

APPENDDC F continued

Table II (continued): J'tk>nthly mean number per liter (Van Dorn total) of zooplankton at Site II of the Dig Eau Pleine Reservoir.

IIUllber tetith of Total in Cerio- ~- Le2to- Calan- Cyclo- Roll- EJ,h1- Oatra- Dates or

~ ~ Dathnla daphn1a O!IOffla !2!!!!!! My:rothrb Lezd1g1a Ch~oJ'lle !!!?.IL .2!5.-- !Wl!1 l!9liL !w.. Jl!lil .!!B._ ·-·· f.iw!I

:'ay, 1974 1,0 51.)2 1,88 0,00 17,69 0,00 O,J8 0,75 0,00 l,J8 288.6) 168,06 512,Jl 0,00 0,00 2 10'12,40 2,5 29,62 0,?5 0,12 ?,J8 0,00 0,12 0,62 0,00 1.00 2)0,19 142,?5 41),06 0,00 0,00 2 825,61 5.0 25,50 0,?5 0,12 7,00 0,00 0,00 o • .50 0,00 0,12 J09, .50 61,06 .:,64,44 0,00 0,00 2 768.99

!'!ean J5,4B 1,12 0,08 10,69 0,00 0,16 0,62 0,00 0,8J 276,11 12:,,96 429,94 0,00 0,00 8711,99

Ju_!\e, 1974 1,0 9J,OO J,.50 0,?5 24,62 o.oo 0,12 20,44 0,25 4,75 60,12 )f+.06 1n.94 0,00 0,00 2 41),5.5 \0 2,5 J9,J9 1.50 0,12 17,?5 0,00 0,75 24,12 0,25 2,7.5 69,00 28,00 229,J?. 0,00 0,00 2 412,94 ~ ;.o t.JB 9,50 a.co 6,75 0,00 0,00 2,81 0,00 2.12 121,)8 16,00 45,J2 0,00 0,00 2 210,26 ~!ean 46,25 4,8) 0.29 16.)8 0,00 0.29 15,79 0,16 J,21 8),.50 26,02 146,66 0,00 o.oo )45,.58

July, 1974 1,0 15.25 0.25 19,75 7,75 o.oo 0,00 5,25 o.oo 10 • .50 2)11, 50 52,)7 186,75 0,00 0,00 1 5J2.J7 2,5 11,00 0,00 1),.50 9,75 o.oo o.oo 9,25 0.25 10.75 192,50 16,.50 1611,00 0,00 0,00 1 417 • .50 5,0 P.,25 4,50 1,00 0,00 o.oo 0,00 o.oo 0,00 2.25 512.00 16.00 2,6J 0,00 0,00 l S46,fJ

• l·'.ea.n ll, .50 1.58 11.42 5,8J 0,00 0,00 4,8) o.oe 7,6) )09,67 28,29 117,79 0,00 0,00 499,!!2

>.u;:;., !974 1,0 25,16 0.56 )Ii. 56 66,67 0,00 0,00 97,42 0,16 15.2.5 162,56 16,04 66,JJ 0,00 0,00 :, 5l'lt,77 2.5 22.oP, 0,75 41,25 Jl.00 0,00 0,00 7),J? 0,08 lJ,79 J05,?l 22,00 61,JJ 0,00 0,00 J 571,)6 5.0 JJ.17 6.42 26,00 7,71 0,00 0,00 65,21 0,00 1e.aa 48J,04 27,29 8J,79 0,08 0,00 J ?51.59

Hean 26,81 2.,58 JJ,94 J5,1J 0,00 0,00 78,6? 0,08 15.97 )17,ll 21,78 77,15 O,OJ 0,00 609,25

Sei;t., 1911 !fot Saapled

~·ea.."l 1,0 26,88 J,23 10.90 )5,48 0,00 0,04 67,42 0,04 9,16 96,57 :,8,21 127,92 0,07 0,00 11 i.1.5,92 ~:ean 19.62 J,?1 9,61 211,00 0,00 0,18 6.5.17 O,OJ 7, ?'+ 119,16 :,0,06 10),68 0,08 0,00 11 Jt'J,04

APPBJDIX F continued

~able III: '.•1onthly mean number per liter (Van ::Jorn total) of zooplankton at Site III of the Big Eau Pleine Reservoir.

Nu•l-.r Depth of Total

1n Cerio- Dia'lhan- Lepto- Calan- Cyclo- Roti- Eph1- Oatra- Date■ of ~ !!.!.!!! D&phnia c!np~n1a oso,a ~ Hacrothr1x Lezd1t!:1a Ch~dorua ~ ~ llaupl11 R2.!!!!... ~ plaln coda ~ ~

~e:,t,, 197.l 1.0 ,511,!!8 .5,7.5 4),7.5 .56,44 0,00 0,00 J.50,00 0,00 12.2.5 112,94 20,62 7.l,00 0,00 0,00 2 729.6) 2,5 52,25 7,62 5:,00 26.2.5 0,00 0,00 1142,62 0,12 15,00 12), 50 29,J8 75,25 0,00 0,00 2 e24,99

~'.ean 5J,56 6,69 J.8,)8 41.J4 0,00 0,00 J96,Jl 0,06 lJ,62 118.22 25.00 ?4,12 0,00 0,00 m,JO

C-:~., 197.l 1,0 60,75 6,7.5 8,00 126,50 0,00 0,00 lAJ,25 0,00 46,7.5 60,00 .50, 7.5 ?A, .50 0,2.5 0,00 1 621,2.5 2.5 J::..50 5.25 12.00 6/l, 50 0,00 0,00 lBJ, 50 0,00 lJ,25 5J,25 21,7.5 82,25 0,25 0,00 1 471, 75

liea.n 46,12 6,00 10,00 97,50 0,00 0,00 18J,J8 0,00 J0,00 .56,62 J6,25 eo.:,e 0.25 0,00 ,51,6,?.4 \,D

1,0 0,00 0,00 9,25 0,00 0,00 9,.50 0,00 lJ,25 •5,75 5,50 4,75 0,00 o.oo 1 .5J,OO "' :~ov. • 197.l 5, .50 2,5 5,25 o.oo 0,00 9,50 0,00 0,00 6, 50 0,00 9 • .50 5,75 4,2.5 J,7.5 0,00 o.oo 1 44.2.5

Eean .5,Je 0,00 0,00 9,JB 0,00 o.oo A,00 0,00 11.)8 5. 7.5 4,88 4,25 0,00 0,00 49.0:?

:ec._ 197) 1.0 .5.00 0,00 o.oo J,7.5 0,00 0,00 1.00 0,00 9, .50 lJ,.50 6.00 J6.2.5 0,00 0,00 1 7.5.00 2,5 4,25 0,00 o.oo 5,.50 0,00 0,00 2.7.5 0,00 11,00 22.2.5 10.00 Jl..50 0,00 0,00 1 f7,2.5

;~t?an 4,62 0,00 0,00 l1,62 0,00 0,00 1,88 0,00 10.2.5 17,118 8,00 JJ,88 0,00 0,00 e1.1:,

·'"·"•. 107 .. 1.0 0.50 0,00 0,00 2 • .50 0,00 0,00 18,75 0,00 10.2.5 9,00 29,2.5 98,7.5 0,2.5 0,00 l 169,2.5 1-'.ean c,,.50 0,00 0,00 ;>,.50 0,00 0,00 18,7.5 0,00 10,2.5 9,00 29,25 98,7.5 0,25 0,00 169,25

F£·'t. • 1974 1,0 0,00 0,00 0.25 0.8J 0,00 0,00 1,67 0,00 O,JJ 0,17 4,17 1.00 0,00 0,00 J 8,42 ?~ean 0,00 0,00 0.25 0,8J 0,00 0,00 1,67 0,00 0,JJ 0,17 4,17 1,00 0,00 0,00 e,,,2

~:a.r .. 1974 1.0 0,00 0,00 o.oo 0,00 0,00 o.oo 0,00 0,00 0,00 0,00 0.25 o.oo o.oo 0,00 1 0,2.5 liean o.oo 0,00 o.oo o.oo 0,00 o.oo o.oo 0,00 0,00 o.oo 0,25 0,00 0,00 0,00 0,2.5

Afr,, 1974 1.0 0.2.5 0,00 0,00 0,00 0,00 0,00 0,7.5 0,00 0,00 J,.50 0,7.5 1.50 o.oo 0,00 1 6,75 l':ean 0,2.5 0,00 0,00 0,00 0,00 o.oo 0,7.5 0,00 0,00 J,.50 0.15 1 • .50 0,00 0,00 6,75

APPENDIX F continued

':'able III (continued) : Monthly mean number per liter (Van Dorn total) of zooplankton at Site III of the Big Eau Pleine Reservoir.

Nuaber Depth of Total

!.n Cerl.o- D1arhan- Lepta- Calan- Cyolo- Rot1- Ei,hi- Oatra- Date■ ot ~ !-'.~t.~?"'!J ~ d~.1,hnia oscna Boaioina Hacrothrix Le,Xdi,ia Ch.xdorua ~ .2l!!L. tlaupl 11 P.2!£!... !!a. p1ala ~ Ava'd J:eana

fay, 19~ 1,0 68.50 J,50 0.12 7,62 0,00 0,00 1,lill o.oo J,00 225.00 1:,e.87 101,18 0.25 o.oo 2 ,.9.i.6 2.5 61.00 0.12 0.12 2,?5 0,00 0,00 O,JB 0,00 2,86 1112.62 10.5,82 141.62 0,00 0,00 2 7,'?,Jl 5.0 J?,PA 0,50 o.oo 1.62 0,00 o.oo 0,25 o.oo 1.12 47J,06 ?9,56 129.69 0,12 0,00 2 ?lfl,80

1':ean :,..12 l.J8 0,08 4,00 o.oo 0,00 o.69 0,00 2,4) J?0.22 108,0B 124,l? 0,12 0,00 66.5,21

Jur.e, 1974 1,0 75,00 1.50 0,12 25,JB 0,00 o. 12 18.68 0,25 27,2.5 76,)2 J0.82 2JJ,00 0,12 0,00 2 41!A,56 2.5 46.}'l 0,25 0.12 10.06 0,00 0,00 8,J2 2.00 14.25 50,50 lJ,50 86,J2 0,00 0,00 2 2Jl,?O 5,0 20,PS 0,62 o.oo 1.2.5 0,00 0,00 1,25 O,Jfl 6,00 6) • .50 8,J8 19,.50 0,00 0,00 2 121.76

"' ~'.ean 4?,11;> 0.?9 0,08 12.2J 0,00 0,()11 9.42 o.eo 15,8) 5),44 1?,.56 112,94 o.04 0,00 29Cl,6? v

~~:!.y, 19?4 1.0 20 • .50 o.oo 1.00 6.50 o.oo 0,00 J,6J o.oo 16.lJ 159.25 )9,00 259 • .50 0,00 0,00 1 .50 5, 50 2.5 17,00 0,50 n.2.5 l.?5 0,00 o.oo 1.00 0,2.5 8,00 192.00 lJ,50 124;!0 o;oo o.oo 1 JU.25 5.0 lJO. 2 5 J,?5 1..50 0.50 0,00 0,00 o.oo o.oo 5,75 156.12 l?,?5 19.50 o.oo 0,00 1 JJ5. lJ

l:ean 55.92 1,42 J.,58 2,92 o.oo o.oo 1.,. 0,08 9,96 169.12 2),42 1)4. 50 o.oo o.oo 402,46

i-'.lf:_. I l??t+ 1.0 2r..25 0.25 J2,50 78.62 o.oo o.oo 25.25 0.12 12,JO 2JJ.50 24.69 47,50 0,00 0,00 2 4AJ,06 '.', 5 ;~.(\(:, o.oo J0.44 66.00 0,00 o.oo 29.25 0.50 11.12 220.J'l J?,00 J9.t-8 0,00 0,00 2 4(6, 1? 5,0 i<6.~'l 0.12 15,62 ?,?5 0,00 0,00 2,?5 0.12 14,88 2411. ?5 ?.5,J2 21,69 o.oo 0,(10 2 419,es

rean 4';'.C4 0,12 :>6.19 50,79 0,00 o.oo 19.08 0.25 12,?9 2J2,ea 29,00 J6,29 0,00 o.oo 456,4J

:.e:,t., 1974 1.0 J2, .50 0,00 .5J,75 159,50 0,00 0,00 165,JB 0,25 19,?5 150,88 11.25 .59,25 0,00 0,00 1 652,50 ?.5 4C'.?5 o.oo 70,50 1?4.?5 o.oo 0,00 20),.50 0,25 16,40 1.54.25 14,00 149,ee o.oo 0,00 1 e::>4,25 5,t' 1: .• 7;" 0,:?.5 41.25 20.50 0,00 0,00 112.50 0,00 1.25 128.50 .5,JO .54, lJ 0.00 o.oo l J8?,50

Y.~ean J0,6? 0,0'3 55,17 119.25 0,00 o.oo 160,46 0,16 14,lJ 1114, .9• 10,21 87,7.5 o.oo o,oo 621,i.2

~-e~n 1,0 ?.7,0.5 l,J6 10,?J )6,68 0,00 0.01 .59,9.5 0,05 lJ,14 80.?5 27,84 76,48 0,07 0,00 lJ ))4,11

~:ea.n 26,?4 1.27 11.06 26,49 0,00 0,00 61.07 0,11 10.07 91,64 22,8) 60,7) 0.0.5 o.oo l) 312.06

APPENDIX F continued

Table DI: Monthly mean number per liter (Van Dorn total) of zooplankton at Site Nin the Big Eau Pleine ~eservoir.

llunbar Depth ot Total

1n Cerio- Dl11phan- Lepto- CalQn- Cyclo- Rot1- lph1- O■tn- Dde■ of ~ ~ D.-rhnia. darhn1a 0$01"1:'..'. ~ Macrothr1x Lot!!1e;ta Ch,ldonia ~ ~ Naupl11 po1cta ~ plnla ~ ~ !•:ear.a

Sept,, 197.l 1.0 4?,62 J,2.5 24,2.5 142.,50 0,00 0,00 182,12 I

62,62 lJ,62 0,00 1.5,00 ?6,.5() 0,00 0,00 2 S'?.47 2 • .5 ,5.'3.25 O,J8 41,62 lJ0,7.5 0,00 0,00 220.2.5 o.oo lJ, )13 85,62 lJ,00 64,.50 O,JS o.oo 2 62e.r, .5.0 lil,J/3 ?,75 4?,.50 1J.J8 o.oo 0,00 22),2.5 0.12 5,J8 114,62 9,62 41.62 0,00 0,00 2 499,62

l·!ean 49.08 2.12 J?,79 95.~ 0,00 o.oo 206.~ 0,04 11,2.5 94,29 12,06 60.es 0.12 0,00 .571, 7.l

Cct., 197J 1,0 19,7.5 J,2.5 .5,75 44,2.5 0,00 0,00 87,25 0,00 1::,.00 49,00 1.5,.50 17,7.5 0,,50 0,00 1 2.57,7.5 2,5 Jl.:.>5 J,75 17,75 61,25 0,00 0,00 11•9. 75 0,00 9, .50 111.7.5 lJ,75 Jl•,50 0,00 0,00 l r)-50 5,0 15.50 ?,00 16.00 15,50 0,00 0,00 25), 50 o.oo 8,00 52, 50 2),7.5 25.00 0,75 0,00 l 22, .50

\0 ~!ean 22,l? J,00 lJ,l? 40,JJ 0,00 0,00 16),.50 0,00 10,1? 4?.?.5 1?,6? 25,?5 0,42 0,00 )4),9) J:a

:;ov. • 197) 1.0 15.00 0,00 0,00 11.00 0,00 0,00 1,75 0,00 7,.50 9,00 4,.50 21,7.5 0,2.5 o.oo l 90,7.5 2,5 6,50 0,00 0,00 28,00 0,00 0,00 11,00 0,00 .5 • .50 11.50 4,.50 26,00 0,00 o.oo 1 e6.oo 5,0 J,?5 0,00 0,00 5,75 0,00 o.oo l1,.50 0,00 2 • .50 14,25 4,00 11.50 0,00 o.oo l 46,2.5

~:ean ~.112 0,00 0,00 21.58 0,00 0,00 J,42 0,00 .5,1? ll,.5fl '•.JJ 19,7.5 0,08 o.oo -,,,..::n !,-,c,, 197J 1,0 2,?5 0,00 o.oo ?,25 0,00 0,00 J • .50 0,00 10, .50 4,2.5 6,.50 10.2.5 0,2.5 0,00 1 4~.2.5

2.5 ?. ? 5 0,00 (),00 26,?5 0,00 0,2.5 8,00 0,00 111,00 21,?5 ?,75 76,?5 0,00 0,00 1 U?,75 5,0 5. 75 0,00 o.oo 6.50 0,00 0,00 5,00 0,00 10,00 lJ.?.5 8,25 29,25 0.25 0,00 l 7'3, ?5

l'.ean 5.2.5 0,00 0,00 lJ. 50 0,00 0,08 5,.50 0,00 11.,50 lJ,25 ?SJ J8,75 0,1? o.oo 95 • .50

~an., 19';'4 1.0 0,25 0,00 0,00 2,00 0,00 0,00 J,7.5 0,00 J,00 ?,2.5 ?,7.5 J24,50 0,00 0,00 1 )48,5') 2.5 0.50 o.oo 0,00 2.25 0,00 0,00 0,2.5 o.oo 2.25 28,00 lJ,7.5 l\2,,50 0,00 0,00 1 129 • .50

~ean 0. Je o.oo o.oo 2.12 0,00 0,00 2,00 0,00 2.62 17,62 10,?.5 20),.50 0,00 o.oo 2)9,00

Fe1',, 19~ 1,0 0,12 0,00 0,00 0,12 0,00 0,2.5 0,88 0,00 2,00 l,!18 59,62 19,J8 0,12 0,00 ) PA,)8

~'.l?M 0,12 (1,00 0,00 0,12 o.oo 0,2.5 0,88 0,00 2,00 1,88 .59,62 19,J8 0,12 o.oo ~.J8

Ya.r., 19~ 1.0 0,00 o.oo 0,00 o.oo o.oo 0,12 0.2.5 0,00 0.2.5 0,1?. 2fl. 7.5 0,12 0,00 l.~ 2 )1,2) 2 • .5 0,00 (1,00 0,00 o.oo 0,00 0,00 0,00 0,00 0,00 o • .50 1,00 0,2.5 o.oo 0,00 l l,7.5

~'.ean 0,00 o.oo 0,00 o.oo 0,00 0,06 0.12 o.oo 0,12 O,Jl 14,88 0,18 0,00 0,81 16.48

.APPENDIX F continued

':'able N (continued) : Monthly mean number per liter (Van Dom total) of zooplankton at Site Nin the Big Eau Pleine Reservoir.

Nu-.ter Depth or Total

in Cerio- D1aphan- I.epto- Calan- Cyclo- !loti- Bphl- Oetn- Dnt.n or ~ ~ Daphn1a dr,phniA ooor.ta ~ 11ncrothr1x 1.eXd1e,1a Chzdol!!! !!2.!L. !'.!!!!_ N1111plH J.!2!!!!.. !!.a. E!!!! .£!W.L ~ •~:w,

Arr,, 1974 l,0 0,00 0,00 0,00 o.oo o.oo 0,00 0,00 0,00 0,00 8,75 1.00 l,00 0,00 0,00 1 10,7.S 2,5 0,?5 (1,(10 11,25 o.oo 0,00 0,00 0,00 0,00 0,00 8,?.5 1,00 1.00 0,2.5 0,00 1 11.~ 5,c 0,00 o.oo 0,00 0,00 0,00 0,00 o.oo 0,00 0,00 5,25 1,50 1.00 0,00 0,00 1 7,?.5

~:ean 0,01' o.oo o,oc 0,00 0,00 0,00 0,00 0,00 0,00 7,58 1,17 1.00 0,08 0,00 10,00

;.Jy, 1974 1.0 69,Y.I 0,)8 (1,00 1 • .50 0,00 0,00 0.12 0,00 1, .50 J0.5,111 164.62 12),62 0,00 0,00 2 6~.9) 2.5 J~ . .n[l o.oo 0,00 1.00 0,00 o.r,o O,J8 0,00 1.62 JJ8,P.2 lOJ,94 1011,74 0,00 0,00 2 59),)8 5,0 34.~8 0,62 0,12 0,88 0,00 0,00 0,00 0,00 O,J8 l120,J2 85,Jl AJ,Al 0,00 0,00 2 6"U,)2

f.:ean 47,?1 O,JJ 0,()1; 1,12 0,00 0,00 0,17 0,00 1,1? )54,911 117.96 10.5,39 0,00 0,00 62P.,e7 IJ) u,

Jure, 1974 1,0 Ph,25 o • .50 0,12 7,12 0,00 0,00 )0,76 0,88 ?.l,7.5 64 • .50 24,5(, 21),56 0,00 0,00 2 44!',(I() ?.,5 25.11 0,1? 0,00 O,A8 0,00 0,00 2,.50 0,12 ?9,69 5),69 10,:,2 JP., .50 0,00 0,00 2 16-1!.9'• 5,0 1J.J2 0,12 0,00 0 • .50 0,00 o.oo o,M 0,12 20,)8 92,i.1. 19,l14 J2,A8 0,00 0,00 2 17'9,RB

!•:can 1,IJ,llJ 0,2.5 0,OI• ?,BJ ·o.oo 0,00 ll,J8 0,J8 2),94 70,21 20.77 94,98 o.oo 0,00 26.5,61

Ju\1, 19~ 1.0 l~.75 0,00 1,7.5 ;>, 50 0,00 0,00 l,?.5 0,00 42,88 186,2.5 26,6) 202,)7 0,00 0,00 1 4!11,f:l? ::, ,5 J?,75 0,00 '.?-,75 1.50 o.oo 0,00 0.25 0,00 110,00 146, 75 11.7.5 J] '.50 o.oo 0,00 1 268,2.5 5,0 29,50 0,00 0,00 0.50 0,00 o.oo 0,00 0,00 16,7.5 1.57.00 7,6J 11,.50 0,00 0,00 1 222,P.8

f.:ean 27,00 0,00 1,8:, 1..50 0,00 0,00 o • .50 0,00 )J,21 16).J) 1.5,)4 81,79 0,00 o.oo )24,,50

Au~., 19?'• 1,0 }'!,)) o.oe )5,25 55.se 0,00 .5,00 18,Be 0,00 19,42 2)9,79 61.25 42,46 0,00 o.oo J ,516,04 ;>,5 :'h.9? 0,00 ;>9,9;> J5.08 o.oo 0,00 26.)7 0,16 11,51 19?,62 48,25 42,.50 o,oo o.oo :, 4:.>6,)2 5,0 )2,00 O,JJ 24,17 (,,O!J o.oo 0,00 18,2,5 0,16 11,2.5 21'1,lJ 16,54 44,5'• 0,00 0,00 J JG7,45

f!e.ll'! Js.oe 0,14 29,?6 )2,25 o.oo l,67 21.17 0,11 14,06 217,18 112,01 4),17 0,00 0,00 4)6, ?2

Se;'t •• 1974 !lot Sampled

~'.e:1.n 1,0 211,6e 0,62 5,59 24,48 0,00 0,45 27,,. 0,07 11,40 79,94 )4,.52 87,77 0.09 0,14 12 297,29 f1eM 19.613 0,49 6,89 17,.57 0,00 0,17 )4,76 0,04 9,60 8),)) 2?,0l .57,88 0,08 0,07 12 257,57

APPE:IDIX F continued

'l'able V: Monthly mean number per liter (Van Dorn total) of zooplanlrton at Site V 1n the Big Eau Pleine Reservoir.

lfUllbar De;;ith or Total

1!! Ce:::-10- Dbrh'ln- Lepto- Cala.n- Cyclo- Rot1- iph1- Oat.ra.- Dates of ~:o~th ~ ~ c.nnhn1a O!j,OHa ~ M11crothrix Lezd!e;ia Chl'.dorua ~ .!!,!E.!_ tlaupl11 ~ !m.. ll!!! ~ ~ ~:eana

Se!)t,, 197) 1,0 Jl,50 0,12 Jl.25 54,62 o.oo o.oo 2J7, 50 0.25 17.75 65,50 12.25 80.62 o.oo 0,00 2 5)1.)6 2.5 25,0!l 0,)8 46,25 2?,25 0,00 0,00 212.25 0,00 8.00 4),00 9,75 ~.25 0,00 o.oo 2 4:,7.01 5.0 J6.12 0,62 53,50 2.50 0,00 0,00 )JP.,62 O,J8 2.86 ?!I. 62 5,62 ,56.ee 0,00 0,00 2 575.~

10.0 J.9,00 2,00 55,75 7,25 0,00 o.oo 1,27 • .50 o.oo 1,25 ?7,?5 21.25 48,75 lJ,25 0,00 1 ?0),25 ~:ea.n )5,62 0,?8 46.69 22,90 · 0,00 0,00 JOJ,97 0,16 7,47 66,09 12.22 62,62 J,Jl 0,00 ,561.8)

Cct., 19?) 1,0 25,P8 1,62 1).6?. 20.00 0,00 0.12 185,JB 0,00 11,88 26.75 19,12 19,00 0.25 0,00 2 )21,62 2.5 ;:;,<,,12 7,25 7.,J8 20,88 0,00 o.ou 105,62 0,00 12,00 JO.SO 20,6?. 19,.50 0,00 0,00 2 ))4,97 5.0 2fi,OO 0,75 l?,J!l 211.ea 0,00 0,1)0 190,flll 0,00 9,25 25,25 17,00 . 17,00 0,00 0,00 2 J2),J9 ?,5 ',?I.,()() 0,50 2?, 75 23.00 0,00 o.oc, ~'90.? 5 0,25 9,00 J0,?.5 19,()0 ~'). 75 o.oo 0,00 l 448,75 \.0

O'I l'.ean 25, 50 2,.SJ 12.2e 22.19 o.oo O,OJ 215, 5) 0,06 10,.SJ 28,19 18,94 21,Jl 0,06 o.oo )57.15

::ov., 197J 1.0 10, 50 0,00 o.oo 20.25 o.oo o.oo 5,75 0,00 10.25 2,75 5,75 4,?5 o.oo 0,00 1 59,SO 2 • .5 10,00 0,?.5 0,00 )2,00 ~.oo o.oo 6,25 0,00 9,7.5 2.00 12.25 lJ,00 o. 50 0,00 1 ('6,00 5.0 li,25 0,00 o.oo 19,25 0,00 o.oo 8.00 o.oo 10.75 9,25 7,00 14,75 0,?.5 0,00 1 n.so

?'.en..~ ')._511 0,08 o.oo ;>J.8J 0,00 0,00 6,67 0,00 10.2.5 4,67 e.J:, 10,67 0,2.5 0,00 ~.66

tee,, 197) l.O J,75 0,00 o.oo 7,50 0,00 0,00 l,?5 0,00 .5,00 11,75 2,75 9,00 0,00 0,00 l 4).00 2.5 5.00 o.oc 0,00 9.50 0,00 0,00 2,2.5 0,00 7,75 16.SO 4,75 2J,25 0,00 0,00 l 69.co 5,0 6,25 0,00 0,00 14 • .50 0,00 o.oo J,25 0,00 10,75 9,50 7,25 14, .50 o.oo 0,00 1 66,00 7.5 J~. 50 0,00 0,00 5,00 0,00 0,00 5.25 o.oo 2,25 16.25 5,25 9.25 0,00 o.oo 1 "8,25

t:ttnn 11,87 0,00 0,00 9,12 0,00 0,00 J,00 0,00 6,114 lJ,.50 4,75 14,00 0,00 o.oo ,Se.68

Jan,, 19-.,,. 1,0 1.50 o.oo 0,00 0,75 0,00 0.110 O,SO 0,00 6,SO )6.25 51,25 )J,75 0,00 0,00 1 1)0.~ 2,.5 :? • 50 0,00 0,00 2.25 0,00 0,00 o.oo o.oo 6 • .50 2B,OO J2,75 19,25 (1,00 o.oo l 9l,75

t'.eM 2,00 0,00 0,00 1 • .50 0,00 0,00 0.25 o.oo 6 • .50 )2,12 42,00 26,.50 0,00 0,00 llo.t'7

Fe~., 19~ 1.0 1.50 0,00 0,00 0,67 0,00 0,4? 0,17 0,00 7,17 J?,00 51,42 JS.92 0,2.5 0,00 ) l)lt.52 2,5 0, 5-q 0,00 0,00 o. _so o.oo 0.08 0,17 0,00 2,67 22.2.5 28,SO 18,42 0,17 0,00 J ?J.Jlt

?~ea.n 1.04 0,00 o.oo o. 58 0,00 0.25 0,17 o.oo 4,92 29,6) 39.96 ?.7, 17 0,21 0,00 10J,9J

APPENDIX F continued.

':'able V (continued) : i•1onthly mean number per liter (Van Dorn total) of zooplankton at Site V in the big Eau Pleine Reservoir.

ll1111ber Depth of Total

~n Cerio- !H~;,han- l.epto- Calan- Cyclo- Rot1- Eph1- Oatra- Datea of !:o~t~ ~ ~ dar'in111. O~O'i:-t. ~ Macrothr1x Le,ld181.a Ch,ldorus ~ ill!._ llaupl11 polda !!!!L p1ala ~ ~ ~

''..:..r,, l9?4 1,0 o.oo 0,00 0,00 0,00 0,00 0,00 0,12 o.bo 0.-00 J.)8 26.12 11,2.5 0,00 0,00 2 40,87 2.5 0,00 0,00 0,00 0.12 0,00 o.oo 0,00 o.oo 0,00 2,25 J.88 2,88 o.oo o.oo 2 9,1'.l 5,0 0,00 0,00 0.00 0.00 0,00 0,00 0,25 o.oo o.oo 0,50 lJ,75 0,75 0,00 0,00 1 15.25

Mean 0,00 0,00 0,00 o.04 0,00 0,00 0.12 0,00 0,00 2,04 14,59 11,96 0,00 o.oo ?1.~

.\;!" •• 1974 1.0 0,00 0,00 o.oo 0,00 0,00 0,00 0,25 0,00 0,?.5 16.,50 0,7.5 J,00 o.oo o.oo l ;>0,75 2,5 0,00 0,00 0,00 0,2.5 0,00 0,00 o,;,5 0,00 0,00 16.25 J,25 J,25 o.oo 0,00 l 2).25 5,0 (1,('I) 0,00 0,00 o.oo o.oo (\,00 0,00 0,00 o.oo 25,50 2,75 4,25 0,00 0,00 1 J2.5() '.',5 o,co 0,00 0,00 0,00 0,00 o.oo 0,00 0,00 0,00 1.0.50 1.00 .5,25 0,00 0,00 1 16.75

\0 ~:ean 0,('0 0,(.1(.1 0,00 0,06 o.oo o.oo 0,12 0,00 0,06 17, 19 1.911 J,9'• o.oo 0,00 2~.Jl ....J

:•·~y. 10?4 l.0 56,62 o,:,A 0,00 O,J8 0,00 0,00 o.oo 0,00 1.25 J29,75 J29.9'-• 96,t'l o.oo 0,00 2 815,1) ?,5 4J,C'O 0,12 0,00 0,25 0,00 0,00 o.oo 0,00 l,Jll J,58,81 :,,i.44 16J.68 0,12 0,00 2 92,5,(lO 5,0 10.;,5 0.12 o,Je 0,62 o.oo o.oo 0,00 o.oo O,J8 297,00 ~06.~ eo,75 0,00 o.oo 2 7(15,114

10.0 (,.;8 0,00 0.12 0.12 0,00 0,00 0.25 0,00 o.:,a 1220.62 27J,69 89,18 0,62 0,00 2 1590. 7'1 roan J1,Jl 0.16 0,12 0,:,4 o.oo 0,00 0,06 0,00 0,8.5 551,.9• Jl7,25 107,60 0,18 o.oo 10('9,lil

->-~~. 19-;t. 1,0 29,t? 0,00 0,00 0,75 0,00 0,00 8,25 0,25 Jl,82 69,62 19,69 811,00 0,12 o.oo 2 244, 12 :2.5 .,.., "'l,0 .... .,,._ 0,12 0,00 1.12 0,00 o.oo 5, J2 0,12 J2,J8 72,!6 12,82 56,81 c.oo o.oo 2 20~.~J 5,0 15 .. 50 0,00 0,00 o • .so 0,00 0,00 0.62 0,12 JJ,62 55.12 15,J8 4.J~ 0,00 0,00 2 125,21,

lD,O 2G, 0 ~ 0,00 0,00 0.62 0,00 o.oo O,J8 0,00 lJ, 50 145,50 26,91• 7,1,i. 1,62 0,00 2 222.e9 f:ea.n 21.. eJ1 0,0J 0,00 0, 7.5 0,00 o.oo J,64 0,12 27.8J 85,70 18,70 :,e.oJ 0,114 0,00 200.09

July, 1974 1.0 ll,2.5 o.oo 0.25 0.15 o.oo o.oo 2 • .50 0,00 26,,50 160,50 2J,7.5 682.87 0,00 0,00 l e9~.:,1 2.5 ~.25 o.oo 0,50 0,25 o.oo 0,00 8,12 0,00 49,50 1:,4.88 10.,50 242,00 o.oo 0,00 1 4.55.00 5,0 10, '.'5 0,00 0,00 o • .50 0,00 o.oo 1, ,50 0,00 J9,2.5 7.5,J7 6,2.5 ,56. 50 o.oo 0,00 1 190,lJ

10,0 0,75 o.oo 0,25 0,00 0,00 o.oo 0.?.5 0,2.5 1.00 2,75 0,25 4,25 0,75 0,75 l 11,75

J'.ea..'\ f.00 0,00 0,25 O.J~ 0,00 o.oo 2,97 o,06 29,06 9J,)8 10.19 246.40 0.19 0.19 :m.01

APPE:~uIX F continued

TaLle V (continued): Monthly mean number per liter (Van Dorn total) of zooplankton at Site V in the 131g Eau Pleine Reservoir.

Nu:iber Dc:,t~ of Total

!.~ Corio- ~- 1'l11to- Colan- Cyclo- Rot1- Sph1- Oatra- D&t.ee or '.'.ot.t~ ~ !l:i-,hn1a d~'1Lnta O~Cr:"11. ~ M.-.crothrlx Le:Lrttrtl\ Ch;rc!on1a ~ ~ Naupl11 polda ££!!... p1ale ~ ~ ill£,.!

J..·..:.;::., 1974 1.0 211.62 o.oo 11,?5 26.19 0,00 0,(10 7,75 0,25 5),Jfl 150,82 41,Jll JA, 50 0,00 0,00 2 J~.14 ?, 5 1,2.6:> o,or l':'.00 15.12 o.oo o.oo l1,)8 0,12 22, 50 141,2.5 2.5,12 2.5,12 0,00 0,00 2 29.5,2) 5. (• .,..., -,Q 0,00 ?;.75 6,00 o.oo 0.00 l1,(JJ1 o.oo 10,62 169.19 21,56 15,75 0,1? o.oo 2 2?J,Pl ._._ . ..,,

10.0 21).P? 0,00 l:',fi? 2.12 0,00 o.oo 2, 50 o.oo 8.50 14J,69 lA,19 12,81 0,12- 0,00 2 ?':'?,)?

~:~i'.."1 2<:.ll o.oo 15. 78 12.J6 o.oo 0,00 11,89 0,09 2J.7.5 l.51,21f 26,.56 2).04 0,06 o.oo 286.~8

:::""rt •• !.911 1.0 ;19.:.>5 o.oo 27,:.>5 lJJ,00 - 0,00 o.oo lJ9.?5 o. 50 )4,00 119,8? 17,50 55'1,lJ 0,00 0,00 1 1061•,2.5 I!

?.5 l,J~ •., 5 o.oo l?.00 9J,OO 0,00 o.oo £'2.00 o.oo J?,75 68,62 .5,00 1911,00 0,00 0,00 1 5)7,12 0:

5.0 t9.00 0,00 29,;,5 J6,75 o.oo o.oo 60, 75 l.?5 111.25 81.60 ?,25 48.?5 0,00 0,00 l )4J,A.5 10.0 47,25 o.oo 2),50 J,7.5 o.oo 0,00 11,7.5 o.oo 4,5,25 647,00 7,lJ 128,)8 0,00 0,25 l 9111,2.5

?~ea.n ,50. 06 o.oo 74,25 66,6?. 0,00 0,00 7),114 0.56 Jl. .56 279,27 7,97 2)1.19 0,00 0,06 '.7].4,98

Le.:~ 1.0 lA.15 0,16 6,0.5 20,)7 0,00 O,OII 115,28 0,10 15,8) 79,26 46,28 127,16 0,0.5 0,00 lJ J.53, 7.3 !'.ean 1?,07 o.2e 7,64 12,)6 0,00 0,02 l1?,29 0,08 12,18 100.)5 40,26 62,88 0,)6 0,0? lJ J00,?9

APPENDLX F continued

Table VI: ~1onthly mean number per liter (Van Dorn total) of zooplank'ton at Site VI below the Big Eau Pleine dam.

N1111ber Dept~ of Tota!

in Cerio- ~- lepto- C&lan- Cyclo- Rotl- Ephl- Oatra- Datea or ~ ~ Darhnla d11phnia ~~ ~ ~!".!! LeytH_fil Chl'.doru11 .!!2!L ~ Naupl11 po1da :fera piala ~ ~ h!!!!!

Sert., l97J !.O 5,25 1.00 18.00 .59.62 o.oo o,oo 101,00 0,00 6,7.5 6.5,62 18,)8 ).51,88 0,00 0,00 2 627,.51> 2.5 11 • .50 l.J8 26.12 1e.12 0,00 o.oo 136.25 0,00 7,75 .51, 62 16.25 ?0,62 0,00 0,00 2 ))9,61 5.0 25.75 2.f\ll ?.l.?.5 1,,50 0,00 0,00 102.00 o.oo 14,50 46,00 )4,12 11),00 0,00 0,00 2 )6), 50

~:ean 11,.00 1.75 21. 79 n.1a o.oo 0,00 llJ.011 0,00 9,67 54,41 22,92 ·17A, 50 0,00 o.oo 44).~)

C-ct., '.'.~7) 1.0 J.7.5 0.62 1.12 82,62 0,00 o.oo JJ.75 0.12 2,12 27,)8 15.00 97,25 0,62 0,12 2 264,47 ?..5 2.6~ 1.::,5 J.50 69,12 o.oo 0,00 69.25 0,00 2,00 17,62 l:?,12 41,62 0,12 0,00 2 219,n 5,0 5.!:'8 1. .50 4.00 45.75 o.oo 0,00 1,0.62 o.oo 5,75 11,00 15,50 108.12 0,12 0,00 2 2J'l.24

Ncan 4.011 1.12 2.87 65.e:, o.oo o.oo 47.87 o.04 ).29 18.67 111.21 82,JJ 0,29 0, 04 240,6'• \0

~·ov., 197) 1.0 J.J8 0.12 o.oo Jl,75 0,00 0,00 7. JO o.oo J,62 lJ,00 5,)8 20,75 0,)8 0,00 2 es. 76 \0 2,5 6.50 0,00 o.oo J),75 0,00 0,00 8.00 0,00 4,)8 lJ,62 1.:,e 10.62 0,50 0,00 2 &1,75 5.0 ).75 o.oo o.oo y1.12 0,00 o.oo l1,50 o.oo J.62 7.)8 5.JlJ 7.12 0,00 o.oo 2 ~5.97

r:ean 1:..91 0.04 o.oo JJ.21 o.oo o.oo 6.46 0,00 J,87 11.JJ 6.05 12.8) 0.29 o.oo 78,62

~:: .. ~O"M! ::ot Sar,y,lc·d •• I..,

..:'-'":-• I !97!;. l.'l 1.25 o.oo o.oo 0.50 o.oo o.oo 0.50 0,00 1),00 20,50 29,50 10,00 o.oo 0,00 1 15,25 2.5 l.00 0,00 o.oo 0.75 o.oo 0,00 0.50 o.oo 11,00 2:,.50 22.25 7.25 0,00 0,00 l 66,25 5,0 0.75 ').00 c.oo 1.00 0,00 0,25 1.00 o.oo 10,50 25.00 J0.00 5,50 (1,00 0,00 1 :;.,oo

!(ec.n :!.,00 o.oo 0,00 0,75 o.oo o.oo 0,67 0,00 11,50 2;i.oo 27.25 7. 5l! 0,00 0,00 71.':'J

~e~., !.9~• l.0 o.oo o.oo o.oo 0.75 0,00 o.oo 0,50 0,00 5,25 JJ.00 26,5() 111.00 0,00 0,00 1 !:'J,.50 2.5 0 • .50 0,00 0,00 0.75 0,00 0,?.5 0,25 0,00 4,00 211,75 24,25 11,75 0,00 o.oo 1 E6,!0 5.0 ?.75 o.oo o.oo 1.50 0,00 o.oo . 0,2.5 0,00 7,00 1111,75 4),25 9,25 o.oo o,oo 1 l?e,75

f'.ei\11 1. Q)J o.oo o.oo 1.00 o.oo 0,08 O,JJ 0,00 5,42 57,50 Jl,JJ lJ,00 0,00 0,00 109, ,,.

.·..ar •• 1'?74 1.0 0,00 o.oo 0,00 0,00 0,00 o.oo 0,00 0,00 0,00 ),25 11,75 21,75 0,00 0,00 1 J~.75 2.5 0,00 o.oo o.oo o.oo 0,00 o.oo 0,25 0,00 0,00 10.25 n.25 111,50 0,0-0 0,00 l 47,25 5.0 ').25 o.oo 0,00 o.oo o.oo 0.00 0,00 0,00 2,00 lB._50 127,25 11,?.5 0,00 0,00 l 159,25

~'~Ca.~ o.o~ 0,00 o.oo o.oo o.oo 0,00 1),08 0,00 0,67 10.67 5).75 15,BJ 0,0(1 o.oo e1.o!:I

. APPENJIX F continued

~able VI (continued) : Monthly mean number per liter (Van Dorn total) of zooplankton at Site VI below the .Big Eau Pleine dam.

Number !lepth ot • Total

1n Cerio- ~- Lepto- Calan- Cyclo- RoU- Ephl- Oatra- Date■ of ~ ~ ~ dal'1in1a o~o:ia ~ 1·1acrothr1x Ley«Ugta Chydorua ,Jor,1 ~ tlauplU po1da

--r- !!!:L p1nla ~ Ave'd t!!!!! A:·r., 19?4 i:ot Sanplad

'.'.3.:1, 19~~ 1.0 2.50 0,50 0,00 7,75 0,00 0,25 2,25 o.oo 0.25 1J9,25 62.25 117, ,50 o.oo o.oo l :m. 5') ;:.5 ::.oo 0,0(1 (1,00 2J.75 0,00 /l,_51) 0,;>5 0,00 0,25 298. 50 101.25 102,25 o.oo 0,2.5 l .521' .oo 5.0 2.75 0,00 0,00 6J,75 0,00 0,00 1,25 0,00 0,00 )88.25 126,00 98,50 0,00 0,00 l 6flo. 50

Pea.n 1.75 0,17 0,00 Jl,75 0,00 0.25 1,25 0,00 0,1? 275.JJ 96,50 106,08 o.oo 0,08 51). )J ~

.!ur.e, 19~ 1.0 lJ,12 0,12 0,00 8,J8 0,00 0,00 0,75 0,00 14,12 86,62 11,88 11.e.e 0.25 0,00 2 147, 12 0 :?,5 20,75 0.?5 0,00 10,J'l 0,00 o.no 0,62 ll,12 9.00 l<T),94 J6,J2 16,68 0,00 (1,00 2 ?0?,06 0 5,0 JC,,3r 0.12 0,00 19,19 0,00 0,00 0,62 0,00 6,00 115,38 69, 50 20,06 0,00 0,00 2 267,25

liea.n 26.1;2 0.17 o.oo 12.65 0,00 o.oo 0,66 o.OI, 9,?l 101.98 J9.?J 16.21 o.oe o.oo 20?,l.5

.!•J!:t. 1974 1,0 21' ,l',8 0,00 0,00 0.75 0,00 o.oo 5,56 0,12 19,1:.> 66.50 9,19 ?..52,)8 0.25 0,00 2 :,82. ?.5 2.5 25.M o.oo 0,25 0,50, 0,00 o.oo 4,00 0.50 17,2.5 75,12 6,50 18!!.12 0,00 o.oo 2 :,1e.,o~ 5,c :5,75 0,00 0,00 0,25 0,00 0,00 7,00 0,25 22,62 65,liJ; 11,)8 l?O,J2 0,25 0,12 2 JlJ,J'l

1·~ean ;C.15 0,00 0,08 0,50 0,00 0,00 5, .52 0,29 19,66 69,02 9,02 20),61 0,1? 0,04 JJ~.c6

At:~.• :!.9?1~ !,O J~.oo 0,JJ 21.17 116,09 0,00 0,08 ??,25 0,08 ?0,1•2 298,50 211,1:, 101,59 0,00 0,00 J 69'1,64 ,, < .. ., "'l. C."l ... . ,, - 0.25 17. 58 ll;>,11;:, 0,00 0,0'1 82,J? 0,00 15,1? 25c, 54 19,8) 11?,96 0,08 0,00 J th?,12 5,c :~.C:? 0,33 5,9;:, ?7,25 o.oo 0,00 ~0.25 0,00 11.46 1125,lJ 14,?1 109,21 0,00 0,1? 'I 6~9 • .50 .,

1:ea.n 2~.00 O,JO 14,89 85,25 0,00 0,05 69,96 O,OJ 1.5,68 )26, ?2 19,56 109,.59 O,OJ 0,06 66'.',l.2

~e:---• .• • 1971• i:ot Sllll!Jl'!.ed

•.e."'~ l,O 9,21 0,27 4,0J JO,E\2 0,00 O,OJ 22,89 O,OJ 8,46 ?5,J6 21,40 100,JO 0,1.5 0,01 10 272,95 ?!ean 10.e1 0,J6 J.96 25.ei~ 0,00 0,05 24,59 0,04 7,96 9'1,66 Jl,98 ~-56 0,09 0,02 10 21.5.12

101

APPENDIX G

The percent composition of the 9 major taxa of zooplankton in the Big Eau Pleine Reservoir during September, 1973 to September, 1974, based on Van Dorn total, all depths averaged.

Site I Site II Site III Site IV Site V Site VI

Roti fera 31.6 27.1 19.4 22.4 21.0 27.1

Copepod nauplii 22.0 31.1 29.3 32.2 33.4 34.6

Chydorus sphaericus 12.0 17.0 19.7 13.4 16.2 9.0

Cyclopoid copepods 8.0 7.8 7.3 10.6 13.4 11. 7

Bosmina longirostris 11.5 6.3 8.5 6.8 4.0 9.4

Daphnia w_. 9.7 5.1 8.6 7.6 5.6 3.9

Calanoid copepods 0.7 2.0 3.2 3.7 3.8 2.9

o. leuchtenbergianum 3.1 2.5 3.5 2.7 2.4 1.4

c. reticulata 0.9 1.0 0.4 0.02 0 .1 0.1

Total 99.5 99.9 99.9 99.4 99.9 99.9

102

Table I: Significance of correlations between physical and chemi-cal cha rac teri st i cs and zooplankton numbers at Site I in the Big Eau Pleine Reservoir (+ = significant positive correlation at the 95% 1 eve 1, and ++ at the 99% 1 eve 1; - = s i gni fi cant negative correlation at the 95% 1 eve l , and -- at the 99% 1 eve 1; and*** = corre 1 a ti on of a variable with itself).

e E

::, -c: "' "'. "'

~ "' .., .,, .., ,:::

~ -0 0 ... .. 0 Cl. ... .,., r.. Cl. ... 0. "' >, "'

.., ~

~ ..,

C. Cl. ,::: >< 0.

..., _o ::, Cl. 0 :;:; -"' .... .... .., 0 "' C: C: 0 ::, u .... "' Cl. r.. Cl. .., ,_ C:

ii u "' Cl.

Cl. ·~ ... ::, -0 "' ::, ..., 0 "' C: .., a, .. a, .., .., .... a,

j u ,::: u ._

-0 "' -0 .., f > u ~ -0 .., 0 r..

j ;o

:c .. 0 ..., ::, "' 0 g_ Cl. .. u r.. C.

.., .., QJ ,,, ::, C: 0 .... .. .. u Cl. "' r.. "' ~ ... ....

~ Ii i "' ~ ..., .....

"' i5 ul al .,;I ,i1 _j1 ul _;1 "' 8 0 Ill 3 VI VI .... u u ex: 0

Water depth at dam ***

Secch1 disk ***

Sample depth + ***

Temperature ++ ***

Dissolved oxygen ***

Daphnh spp. + ++ ***

£. ret1culata + ***

~- leuchtenber9ianu~ ++ ++ ++ ***

B. lon9irostris + ++ + ***

!!_. lat1cornis -!::.· 9uadran9ular1s ***

C. sehaericus ++ ***

!::_. k1 ndt1i ++ ***

Calanoid copepods + ++ ++ ++ .... Copepod naupl ii ++ + + ++ ++ ++ *** Cyclopo1d copepods ++ ++ t+ ++ ++ ***

Rot1fera ++ + ++ ++ + ++ ++ ++ + ***

Daehnia ephipfals ***

Ostracoda ++ ++ ***

103 /

APPE~DIX H continued

Table II: Significance of corre 1 a ti ons between physical and chemi-cal characteristics and zooplankton numbers at Site II of the Bi g Eau Pleine Reservoir (+ = significant positive correlation at the 95% le ve 1, and ++ at the 99% leve 1 ; - = s i gni fi cant negative corre la ti on at the 95% leve 1, and -- at the 99% leve 1; and *** = correlation of a variable with i tse 1 f).

E E

:, C ...

"' ...

i "' l "' "O C ·~

~ "O ... "' 0 "' 0, ... Cl. "' "' s=

>, .. "' "'

~ "' ci. Cl. Cl.

)( ci. ,,_, .t:l a. 0 '.c: s= ~ ..,

f 0 "' C C 0 :, u ... .,, a. Cl. '; "' I.. ·~1 u "' a. a. :;; "' :, "O "' ,,_, 0 C "O "' ..

"' "O "'"' "'

ffl u s= u .., "O .... "' "O

"O "' > u -g "O g_ ... j

0 ... .... 41 I.. 0 .., :, .... 0 0 "' u s= CII "' "' "' C a. 0 ..... "' "' u t i "' ... _,.

"' "' u .... ... ... u "' - a. ,,_, .., ~ "' .. ;; ul 01 ..;1 :.:I _;, ul _;I ~ 0 >, 0 "' .,, V, ..... u u °' 0

Water depth at dam "** Secchf disk ++ •••

Sample depth - •*~

Temperature - ♦ ••* Dissolved oxygen + ••*

Daphnfa spp. + ++ ***

C. retfculata ♦ ***

D. leuchtenber~ia~u~ ++ ++,. ••*

!· longirostris + + + •••

~- laticornis ••• !:: ~adrangularfs ***

£. !.e!!_aericus ++ ++ ++ ··~ b_. kfndtff + ++ + ***

Calanoid copepods ++ + - ++ ++ - ••• Copepod nauplii ++ - + ••• Cyclopold copepods ++ - ++ ♦ •••

Rotffera ♦+ ++ ++ •••

Daphnia ephfpials ••• Ostracoda •••

104

APPENDIX H continued

Table I I I: Significance of correlations between physical and chemi-' cal characteristics and zooplankton numbers at Site Ill of the Big

Eau Pleine Reservoir (+ = si gni fi cant positive correlation at the 95% level, and ++ at the 99% level; - = significant negative co rre lat i on at the 95% level, and -- at the 99% level ; and*** = corre la ti on of a variable with itself).

e e :,

C: "' .. .. "' "' "0 "' _"0 C: ~ ·;: "0 &. .., QI .,,1 0 '; "" ...

~ "' 0. cu .. ,.,

"' .. "' ';

i QI 0. 0. ·;;_

.s::: >(

~ .., .&> -~ 0. 0 .s::: ... .., cu 0 "' C: C: 0 :, u :c ..,

"' 0. ... 0. QI ... C: -~1 u "' 0. 0. cu :, ,::, "' :, .., 0 "' C: "0 QI .. QI .., ,::, .., .,

j u .s::: -~ u !.. .., ,::, "' "0 "O "' > u -.:, ,::, "C 0 ...

j 0 ... :c ., ...

" .., :, C: .... "' C: 0 0 0. QI u

0. QI ., QI 0 "' ::, C: 0. 0 ..... .. cu u 0. "' ... ... .. cu ... .., u E 15 "' CL u .., .., .. ., "' ;; ul 01 c,;, ,.=, _;, ul _;, .. 0 ,., 0 "' :a V, V, .... u u u "" 0

----

Water depth at dam **~

Secchi disk ++ •••

Sample depth + *** Temperature ++ + <1t.l!,1'

Dissolved oxygen ++ ••• Daphnia spp. ++ ++ • •• C. reticulata + •••

D. leuchtenbergianu~ + • •• 8. lon9irostris ++ •••

"'· laticornis ••• -----L. quadrangulads + *** C. sphaerfcus ++ ++ ++ ••* .!,_. kindtii ••• Calanoid copepods + + ++ ••• Cope pod naup 1 i i ++ ++ + + ++ ••• Cyclopoid copepods ++ ++ ++ •••

Rotifera + ++ •••

Dap!1._<!_i<!_ ephipials ... Dstrdcoda •••

105

APPENDIX H continued

Table IV: Significance of currelations between physical and chemi-cal characteristics and zooplankton numbers at Site IV of the Big Eau Pleine Reservoir (+ = significant positive correlation at the 95% 1 eve 1, and ++ at the 99% leve 1 ; - = significant negative correlation at the 95% 1 eve l, and -- at the 99% level; and *** = corre la ti on of a variable with itself).

e l

:, C "' .. "' "' '8 "' "O C ·;: "O .,

I g_ C1. ... ... c,, .. .. ., ..

.c >, .. .,

"' -;

i ! C. C1. ::,. ,.

,;__ .... .0 0 .c _,., .... ., 0 "' C C 0 :, u .s:: ... "' C1. .. C1. '; ., e .. C

·-1 u .. 0.

Q. ~ a., :, "O "' .... 0 ... C "O cu ... ., -0 "O .... .. j

u .c; u .. ... "O .. "O "O .. > :; u "O "O 0 "O 0 ..

j 0 - cu ... 0 :, C ... "' C 0 Q. a, u .. .c C. a, a, a, 0 "' :, C 0. 0 ..... "' ., u 0. "' .. .>< .. a, u .. .... u 15 I "' C. ... ... .. a, .. ..;, cl ..;, i:1 j1 ul j1 ~ 0 >, 0 "' 31: .,, VI .... Cl u u "" 0

Water depth at dam **" Secchi disk ++ ... ,!f

S1111ple depth ***

Temperature ++ .... Dissolved oxygen ++ •**

Oaphni a spp. ++ ++ ++ ••• C. reticulata . ... !!.· leuchtenbergianum ++ -- - ••• !· longfrostris ♦ ++ •••

"· latfcornis .... !:: 9uadran9u 1 a ri s ••• f.. sphaericus ♦♦ ++ ♦+ .... j,_. kindtii - ♦+ ♦+ ••• Calanoid copepods + ♦♦ ••• Copepod nauplii ♦+ ♦+ ♦+ ♦♦ ••• Cyclopoid copepods - ♦+ ++ ··~

Aotffera ♦+ ++ ♦+ .... Daphn~ ephipials ♦♦ ♦ ••• Ostracoda •••

\---

106

APPENDIX H continued

Table V: Significance of corre 1 a tions between physi ca 1 and chemi-cal cha racteri s ti cs and zooplankton numbers at Site V of the Big Eau Pleine Reservoir (+ = significant positive corre 1 a ti on at the 95% leve 1, and ++ at the 99% leve 1; - = significant negative correlation at the 95% leve 1, and -- at the 99% 1 eve 1 ; and*** = correlation of a variable with itself).

e :::,

E C "' .. .. "' "' l "' "0 C -

i "0 .. L 0 .. ... en L .. 0. .. ·:;._ .. .c

,., .. .. "' ";

! .. Q.. 0. .. 0. ... .0 0. 0 .c .., ... .. 0 ., C C: 0 :::, u .c ... "' 0. L 0. .. I.. C:

·-, u ., 0.

0. .. :::, "0 "' :::, ... 0 ., C: "0 .. .. .. -0 -0 ... .. il

u .c u ... ..., -0 ., -0 -0 "' > u ,:, ,:, ,:, 0 .. j

0 :c .. .. 0

..., :::, ... ., C: g 0 0. .. u I,. .. "' .. "' :::, a. 0 ~ .. .. u 0. 0. "' L .., .. .. u L ... u e Ii "' 0. ... ... .. .. .. ul 01 ..;, :ii _;, ul _;, ~ 0 ,., 0 "' =- "' "' ..... Cl u u a: 0

Water depth at dam ***

Secchf disk ++ ... Sample depth ++ .... Temperature ++ + •*· Dissolved oxygen ++ WH

Daphni a spp. ++ + ++ ♦ ~-·

C. reticulata • •• D. leuchtenbergfanum ♦+ - • •• !- longirostris + ++ ++ ....

M. laticornf s •••

!:.· quadra n9u la ri s • •• c. sphaericus + ++ +-f; + ••• !,_. kfndtff + ++ ++ ++ • •• Calanoid copepods + ++ + ••• Copepod nauplii ++ ++ ++ ••• Cyclopoid copepods ++ ++ ++ •••

Rotffera + ++ + ••• Daphnia ephipials ++ ++ + •••

Ostracoda + •••

107

APPENDIX H continued

Table VI: Si gni fi cance of correlations between physical and chemi-cal characteristics and zooplankton numbers at Site VI below the Big Eau Pleine dam (+ = significant positive correlation at the 95% level, and ++ at the 99% level; - = significant negative correla-tion at the 95% level, and -- at the 99% level; and*** = correla-tion of a variable with i tse 1 f).

-----e :,

i C "' "' "' "' ..., "' ..., C ~

~ ·.: 1 0 .,

0.. "' ... "' "' ., .. >, ~, .,

"' -;

~ cu C. 0.. 0.. .r:: >( c;;_ .0 0.. 0 .r:: -"' ... cu 0 C C: 0 :, u .r:: ... "' 0.. ... 0.. cu ... C -~, u "' 0.. 0..

~ Q,I :, ...,

"' ... 0 "' C ..., Q,I "' cu ..., ... Q,I

j .r:: u ... ... -0 "'

j ..., ...,

"' > u "t ..., ·;; ..., 0 ... 0 :c ., ...

0 ~I :, .... "' C: 0 0.. cu u .. C. cu cu "' :, C Q. 0 .... .. cu u C. "' .>< .. cu u ... ... u e t "' 0.. .... .... .. .,

"' 0 ...;, 01 a,;, :ii _;, ....;, _;, ~ 0 ~ 0 "' =- V, "' I- u a: 0

Water depth at dam *** Secchi disk ++ *** Sample depth ••• Temperature ++ "** Dissolved oxygen .... Daphnia spp. ++ ++ ..... c. reticulata ••• 0. leuchtenberglanum ++ ♦ ·•Jt

~- longirost~ + ++ ***

M. laticornis ••• .!:.· quadrangular1s • •• C. sphaericus + + # ++ •••

.!:.· k1ndtii • •• Calanoid copepods + ++ + ++ •••

Cope pod naup 1 ii ++ ++ ••• Cyclopoid copepods + + ••• Rotifera ++ + ++ + + + ++ ••• Oaphnia ephipials ... Ostracoda ++ •••